Habitat loss and fragmentation, exacerbated by the expansion of human activities, are currently the greatest threats to biodiversity. Forest-dependent species such as neotropical primates are among the most vulnerable to these changes. The blond titi monkey (Callicebus barbarabrownae) is a medium-sized primate endemic to the Caatinga and currently classified as Critically Endangered. As C. barbarabrownae is a forest-dependent frugivorous primate, it is strongly threatened by habitat loss. This master thesis is divided into two chapters. In the first chapter, we investigated the spatial patterns and temporal changes in land use and land cover (LULC) classes in the geographic range of C. barbarabrownae and in landscapes with records (presence and absence) of this species. Callicebus barbarabrownae occurrence data were obtained from literature searches. The LULC data, used in both chapters, belong to Collection 7 of MapBiomas. Our results highlight that more than half of C. barbarabrownae's distribution area is currently covered by Farming and Non-Vegetated Areas, with Pasture as the predominant class. In landscapes where the species occurs, Savanna Formation, Pasture, Mosaic of Uses, and Forest Formation were the predominant classes. Pasture has a higher coverage proportion in landscapes of occurrence than in landscapes of absence and is the LULC class with the highest rate of increase over the years. The second chapter investigated the effect of landscape attributes on the density of C. barbarabrownae groups. Density data were collected in the field, from five expeditions carried out in different regions of the species' geographic range in the states of Bahia and Sergipe. We found group densities higher than those previously reported for the species. The models that best explained the variation in C. barbarabrownae group density included forest cover, chronic anthropogenic disturbance index (CDI), and clumpiness index as predictor variables in 300 ha landscapes. Group density is negatively related to forest cover, while CDI and clumpiness negatively affect the group density, although not significantly. Our results suggest that extensive livestock farming is currently the greatest threat to C. barbarabrownae, a species that is occurring in contexts of limited habitat availability. At the same time, group density is higher in landscapes with lower forest cover and remnants of more dispersed habitats, suggesting that groups are confined to the limited available habitat. This scenario raises concerns about the long-term viability of populations of this species, whose apparent persistence in such landscapes may be due to an extinction debt. Restoration efforts, especially in the northeastern and central regions of C. barbarabrownae's geographical range, and the establishment of Protected Areas, can serve as crucial allies in the preservation of this species.

Knowledge of ecological parameters and population trends are key for species  of conservation concern. For marine turtles, annual nest counts are commonly used  for estimating population size. However, complementary information on  reproductive parameters is needed for reliable population estimates. In Brazil,  green turtles (Chelonia mydas) nest mainly on oceanic islands. This study uses long term beach monitoring data (35 years) to describe the reproductive biology and  population trends for green turtles at the Fernando de Noronha Archipelago,  Brazil. There was an increasing trend in the annual number of nests over the  studied period. The average annual number of nests in the first five years of  monitoring (1988-1992) was 38.6 nests, while in the last five years (2018-2022)  it was 285.6 nests. Internesting intervals ranged from 9 to 17 days (mean +- SD  = 11.7 ± 1.3 days; median = 12, n = 1236). Remigration intervals of 3 years  were the most frequent (range 2 to 16 years). The longest reproductive life span  observed was 25 years. Average hatching success was 75.6% (SD = 24.8, range  = 0-100, n = 2612 nests). The growth in the annual number of green turtle nests  observed in Fernando de Noronha suggests conservation efforts initiated in the  1980s likely contributed to the recovery of this population. However, the small  population size and restricted nesting geographic distribution, coupled with the  existence of threats such as fishing and climate change, makes this population still  of conservation concern. Knowledge of ecological parameters and population  trends are key for species of conservation concern. For marine turtles, annual nest  counts are commonly used for estimating population size. However,  complementary information on reproductive parameters (e.g. clutch parameters,  internesting intervals, clucth frequency, remigration interval) is also needed for  reliable population estimates. In Brazil, green turtles (Chelonia mydas) nest mainly  on oceanic islands. This study uses long-term beach monitoring data (35 years) to  describe the reproductive biology and population trends for green turtles at the  Fernando de Noronha Archipelago, Brazil. An increasing trend in the annual  number of nests was found over the studied period. The average annual number  of nests in the first five years of monitoring (1988-1992) was 38.6 nests, while in  the last five years (2018-2022) it was 285.6 nests. Internesting intervals ranged  from 9 to 17 days (mean +- SD = 11.7 ± 1.3 days; median = 12, n = 1236).  Remigration intervals of 3 years were the most frequent (range 2 to 16 years).  The longest reproductive life span observed was 25 years. Average hatching  success was 75.6% (SD = 24.8, range = 0-100, n = 2612 nests). The growth in  the annual number of green turtle nests observed in Fernando de Noronha  suggests conservation efforts initiated in the 1980s likely contributed to the  recovery of this population. However, the small population size and restricted  nesting distribution, coupled with the existence of threats from fishing and climate  change, makes this population still of conservation concern.

Global change and associated increasing anthropogenic pressures on Earth are impacting biodiversity locally, regionally and globally, with negative consequences on the stability of ecosystems. However, the majority of studies on biodiversity-stability relationships have been conducted locally. Only recently it has been proposed that such relationships could become decoupled across spatial scales. Spatial decoupling happens when many local communities are unstable, but they vary asynchronously in space, leading to regional stabilization. Spatial decoupling can thus result in misleading interpretation of local scale stability patterns when the goal is to design regional management strategies. Focusing on multiple metacommunities of French rivers experiencing contrasting levels of flow intermittence, we investigate (i) whether and how land-use influences macroinvertebrate diversity and stability across multiple spatial scales and (ii) whether connectivity loss due to increasing intermittence enhances the relative stabilizing force of spatial asynchrony over local stability, resulting in higher spatial decoupling of diversity-stability relationships. We found that urbanization and agriculture negatively influenced local species diversity and the spatial asynchrony of populations and communities, indirectly reducing the stability of metacommunities through different pathways. However, the significance and strength of those pathways changed depending on the intermittence level and organism group analyzed. Specifically, the diversity of aerial organisms responded strongly to urbanization, whereas the diversity of aquatic species did not. In addition, the relative contribution of spatial asynchrony to regional stability was higher for metacommunities of intermittent than perennial rivers, implying the need to conserve multiple sites to attain regional stability in those systems. Considering that climate change is increasing flow intermittence across river networks, our results suggest that managers need to focus on the spatial dynamics of metacommunities more than on local-scale processes to monitor, restore and conserve freshwater biodiversity.

Global changes act as selective forces responsible for inducing the genotypic adaptation (evolution)  in species over a short period, with little or no information about subsequent ecological effects. As a stress factor in freshwater ecosystems, salinization not only poses a threat to biodiversity and the primary functions and services of ecosystems but also imposes selective pressure on species. However, the way species adapt locally to salinization through microevolutionary processes is poorly understood. Therefore, we investigated the genotypic adaptation capacity of the cyanobacterium Microcystis aeruginosa, a major contributor to global blooms, to increased salinity and the resulting changes in growth and morphology. For this purpose, we conducted a Common Garden experiment with four toxin-producing strains of Microcystis. Before the Common Garden experiment, all strains were divided into three populations (replicas) and exposed to two treatments: the addition of  NaCl (1.5 g/L) and the control (0 g/L of NaCl) for over 100 generations (6-8 months). After this period, each population was exposed to treatments of 0, 1.5, 3, and 5 g/L of NaCl with 3 replicas each in a Common Garden project for an additional 7 generations in order to remove the effects of phenotypic and epigenetic adaptation. After this stage, growth and morphological characteristics were measured. To test how salinity concentrations and fitness factors affect Microcystis growth and morphology, we used Generalized Linear Models. Populations exposed to a concentration of 1.5 g/L during the selection stage (adapted) showed higher growth rates compared to those exposed to the control (non-adapted) and grew in all salinization treatments, indicating an increased salt tolerance driven by selection in genetic variation. Selection also resulted in smaller cell sizes for all strains. Two strains originally grown as individual cells produced colonies in higher salinities. The formation of colonies and colony size increased in non-adapted populations, indicating that adapted populations probably do not need to invest in colony formation in order to survive. The results demonstrate that adaptation to relatively low concentrations (1.5 g/L) of salt also allows tolerance to higher salinities (>3 g/L). We have shown, for the first time, the rapid evolutionary adaptation of a common aquatic primary producer to freshwater salinization over ecological time, with effects on key traits such as  cell size. Such adaptation is likely to occur in other cyanobacteria and phytoplankton species in nature where salinization occurs, with consequences for ecosystem functions and services that are still unknown. Our results justify a broader view of the eco-evolutionary implications of salinization-driven selection in aquatic ecosystems.

Given the current state of degradation of the Caatinga Biome, ecological restoration strategies are of the utmost importance, not only to halt this degradation process, but also to restore the affected communities, making them stable and productive over time. Caatinga restoration programs that seek out new ecological restoration technologies have shown themselves to be promising alternatives for combating the desertification process. For more than a decade, UFRN's Restoration Ecology Laboratory has been developing innovative technologies for planting tree species belonging to the biome, with the aim of combating desertification. This technique enabled the construction of the BrazilDry experiment, the first large-scale experiment to restore the Caatinga, which is currently receiving support from the CNPq as a Long-Term Ecological Project (PELD). This experiment is linked to the international TreeDivNet network, which includes 29 experiments in 20 countries that test the influence of tree species diversity on the functioning of planted forests. In addition to testing the effect of species diversity, this experiment also tests how the facilitating potential of these species influences the performance of restored plant communities. In this way, the work aims to generate technologies applicable to restoration programmes for degraded areas of the Caatinga that promote the resilience and resistance to desertification of the restored ecosystem in the long term. Implemented in 2016, the BrazilDry experiment creates Caatinga restoration models that can make preserving plant biodiversity compatible with better ecosystem functioning. This study is divided into two chapters, both carried out in the BrazilDry Experiment, and aims to understand how diversity and facilitation mechanisms influence the flowering and fruiting patterns of restored communities. In the first chapter, our main objective is to test whether the diversity of tree plants in the restored communities and their facilitation potential influence the number of reproductive individuals in the first 7 years of restoration, and thus answer: I - How many individuals and of which plant species in the restored communities have managed to reproduce in the last 7 years of restoration? II - Whether there is an effect of diversity and/or facilitation on the presence or absence of flowering and fruiting patterns. As a result, we observed that the diversity of trees planted did not influence the flowering capacity of the species. However, there was a positive effect of Facilitation on the flowering capacity of species in the first 7 years of restoration. Diversity and facilitation did not influence fruiting patterns. This may have been due to the low rainfall which causes many flowers to abort, as well as fruit abscission, which can also be produced in smaller quantities when under great water stress. The second chapter assesses how the diversity of species that make up the restored communities affects the phenophases of the species Piptadenia retusa, popularly known as Jurema-branca, in terms of the quantity and the synchronization of fruit, flower and leaf production by this species. With the specific objectives of: I - To test whether the diversity of trees in the restored community influences the number and timing of flower and fruit production by the species P. retusa, and which months produce these food resources for the fauna; II - To test whether the diversity of species in the restored tree communities influences the maximum production capacity of flowers, fruit and leaves produced by Piptadenia retusa over the course of a year. As a result, we observed flowering peaks in the wettest months between March and June, while fruiting also occurred in the first half of the dry season between June and November. The production of floral resources (buds and flowers) and seed production (ripe and immature fruit) differed not only in relation to the months, but also increased significantly with the increase in the diversity of trees making up the restored community. In terms of maximum production capacity expressed by the Fournier index, only the explanatory variable, time, had a significant influence. All the variables showed maximum production in the wettest months, with the exception of mature fruit production, which occurred more intensely in the driest months. Leaf production was, on average, 75 percent of its production capacity in the wettest months, but still maintained 25 per cent of its production capacity during the driest months. This work indicates that restoration models with the presence of nurse or facilitator species should be implemented, given the potential of these species to increase the reproductive capacity of neighboring trees, as well as demonstrating that the diversity of trees planted in restoration programmes can increase the reproductive capacity of some species, thus promoting the replacement of individuals in the community and the availability of food for the pollinator fauna.

Many shorebird species are associated with coastal ecosystems during their annual migratory movements between breeding and overwintering areas. The semi-arid coastal region of northeastern Brazil presents a vast landscape of suitable habitats for these birds. Investigating the use of these habitats by shorebirds as a function of landscape structure and anthropic disturbances is a useful approach to better understand their occupancy patterns in the semi-arid region. In 2022 and 2023 we conducted n=3 independent data sampling campaigns, representing n=111 individual 1km long transects, totaling 804 km, covering the entire coastline of Ceará and part of Rio Grande do Norte. Presence/absence data for the species (Calidris canutus, Calidris pusilla, Limnodromus griseus and Numenius hudsonicus) were collected by means of visual observation using binoculars and spotting scopes. Specific habitat characteristics and other variables, such as proximity to particular habitats, human occupations, and degree of disturbances related to tourism activities were recorded during each transect. In addition, information on landscape variables such as land cover in different classes was collected using satellite images. We analyzed the influence of environmental variables on the occupation of the species through static occupation models, using the MARK program. The three most influential variables in the distribution of the species were the distance from estuaries, urban area coverage and aquaculture. The response of species occurrence along the gradient of variables showed that C. canutus had the lowest occupancy among the species (ψ = 0.31), followed by L. griseus (ψ = 0.44), N. hudsonicus (ψ = 0.71), and C. pusilla (ψ = 0.72). These results indicate the vulnerability of shorebirds to anthropogenic impacts, especially related to habitat loss during the wintering period on the semi-arid Brazilian coast. Our results will help to inform conservation strategies and better define the ecological requirements of this threatened species during the greater part of its non-breeding periods.

Understanding the activity and distribution patterns of animals about environmental factors is crucial for species conservation. In the Atlantic Forest domain, 72% of owl species show population declines, making it essential to conserve both species and habitats. The use of passive acoustic monitoring offers opportunities to collect data on the activity and habitat use of little-studied species, contributing to long-term monitoring and effective conservation. This work seeks to fill gaps in the understanding of vocal activity patterns, detection, and habitat use of owls that occur in the far north of the Atlantic Forest, more specifically, in the north of the Pernambuco Endemism Center, Brazil. Our objectives were: (1) to investigate the vocal activity and detection patterns of two nocturnal owls that occur in the Neotropical region, the Tropical Screech-Owl (Megascops choliba) and the Spectacled Owl (Pulsatrix perspicillata), to contribute to monitoring protocols for the conservation of both species; and (2) to identify the environmental factors that affect the occupancy of P. perspicillata, estimate its population density, and map the hotspots of occupancy and density of the species to aid locate priority conservation areas. In the first part of the study, we found that the vocal activity of P. perspicillata was highest at 9 pm, while that of M. choliba was highest at 7 pm, 1 am, and 4 am. The detection of P. perspicillata was best explained by the effective moon illumination index (p = 0.05) and tree density (p = 0.027) and of M. choliba by air temperature (p = 0.006) and tree density (p = 0.001). In the second part, we identified that P. perspicillata responds to environmental variations both at the patch scale and at the 1000 ha landscape scale, and its occupancy is positively affected by the presence of primary forests and areas with greater topographic roughness. The regions of high occupancy and density are concentrated in protected areas, indigenous lands, and other patches with high potential for conservation. The results of this study may aid to identify favorable scenarios for the efficient monitoring of forest night owls and to establish protocols for the conservation of species that are sensitive to the effects of forest loss and that lack information related to habitat use.

The effects of human alteration of the terrestrial ecosystem impact aquatic ecosystems that receive nutrients from the watershed through surface soil processes. The application of geoprocessing can be a valuable tool for the sustainable management of these ecosystems, assisting in decision-making regarding measures to protect riparian zones and the aquatic ecosystem. The objective of our work was to evaluate the influence of land use in the riparian zone on the water quality of reservoirs in the tropical semi-arid region. The reservoirs were divided into groups – large and medium – according to the maximum water volume (greater or less than 75 hm³). Our hypothesis was that large reservoirs have larger anthropized areas due to the extent of riparian zones, but the consequences on water quality are delayed due to the dilution effect of their larger stored water volume. Whereas medium reservoirs have a more immediate response in eutrophication intensification, since their storage volume is smaller and they become more vulnerable to the climatic effects of the tropical semi-arid region. The study was conducted in 17 reservoirs in the tropical semi-arid region, located in the watersheds of Apodi-Mossoró (RN), Piancó-Piranhas-Açú (RN/PB), and Paraíba River (PB), in northeastern Brazil. Analyses of land use in the riparian zone were performed within a buffer of 100 meters from the edge of each reservoir, through geoprocessing analysis. The categories of land use used were: riparian woodland; dense caatinga; sparse caatinga; bare soil; and urban. The riparian zones of the reservoirs showed a high rate of anthropization due to the occupation of agricultural/pasture areas, bare soil, and urban. The effects of anthropization on water quality received contributions from limnological variables of suspended solids, carbon fractions, chlorophyll-a, and total phosphorus. The suppression of native vegetation may minimize the buffering effect that soils and vegetation exert on the riparian zone. The dense vegetation of the caatinga presented remnants and may not be sufficient to protect against the influx of diffuse pollution to the reservoirs. These reservoirs showed sparse caatinga vegetation in the drainage area, which promotes a greater influx of nutrients when flooded.

Cyanobacteria are among the oldest life forms on Earth. They occur in marine and freshwater environments, grouping around in colonies or filaments, and many species can form potentially toxic blooms. In the Brazilian semiarid region, the occurrence of cyanobacteria is widely recorded in reservoirs for multiple uses, including human supply, which causes great concern not only about the impacts on biodiversity but also on human health. Empirical evidence indicates a sharp increase in these blooms with climate-related changes. In the light of this, the present study investigated the current and future distribution of cyanobacteria (colonial and filamentous) that produce toxins in the Brazilian semiarid region, using the niche modelling approach to estimate the areas for the establishment of these populations, associating the already known occurrence points with the bioclimatic variations inherent to the ecology of the species and the climate scenarios (moderate and pessimistic) projected by the Intergovernmental Panel on Climate Change (IPCC) with focus on the 2081-2100 interval projections. Isothermality, annual temperature variation, precipitation volume of the wettest, coldest and driest quarters, plus the elevation were the variables most important for the potential distribution of the species. The projections showed that the Brazilian semiarid region has high climatic suitability for the occurrence of all species analysed, but the models indicated an expansion of habitat suitability in the future, in both the moderate and pessimistic scenarios, only for Microcystis aeruginosa (colonial) and Planktothrix agardhii (filamentous). Hopefully the information obtained will contribute to the understanding of the effects of climate change in natural warmer environments and possibly guide mitigation efforts, assisting managers in decision-making and in the development of public policies.

Biodiversity patterns are affected by factors such as climate, human disturbances and  biotic interactions, which operate at different spatial scales. Understanding diversity  patterns and their determinants is essential for effective conservation efforts. However,  many regions and taxonomic groups are often overlooked due to a lack of adequate data.  In particular, invertebrates and arid/semiarid regions receive less attention. For example,  ants play a fundamental role in ecosystem functioning, but there are knowledge gaps  regarding their global biodiversity patterns, their response to anthropogenic disturbances  and their relationship with plant composition and diversity. Similarly, the Caatinga, a  species-rich dry forest, lacks clear knowledge about its animal diversity patterns.  Therefore, in this thesis we set out to investigate the determinants of ant diversity at three  different scales: (i) global, testing the effect of climate and topography, (ii) regional,  testing the effect of anthropogenic disturbances and (iii) local, testing the effect of tree  species richness and their facilitation capacities. In addition, (iv) we examined the  determinants of animal diversity in the Caatinga and the correlation of diversity  distribution between different animal taxa. In the first chapter we tested the relative  strength of abiotic gradients in determining spatial patterns of ant diversity around the  world and between biogeographic realms. We used multiple regressions to relate global  ant diversity data to climatic and topographic data. Our findings suggest that ant diversity  is higher in tropical regions, especially in areas with higher annual rainfall and higher  average temperature. However, the abiotic determinants between biogeographic realms  varied greatly, which challenges the generality of the global pattern. This highlights the importance of considering regional historical and ecological contexts when investigating  biodiversity patterns. In the second chapter we tested the influence of chronic  anthropogenic disturbances (e.g. logging and grazing) and habitat loss on ant species  richness (total, specialist and generalist species). We then used multiple regressions to  examine the impact of disturbance vectors on ant diversity patterns. We found that habitat  loss reduces species richness at all levels, including specialist and generalist species,  while chronic disturbance has a particularly strong impact on species overall and on  specialist species. Our findings highlight that it is necessary to include the drivers of  chronic disturbance in order to measure our real impact on biodiversity. The third chapter  examines the impact of tree richness, tree facilitation and the presence of plants with  extrafloral nectaries on ant diversity patterns, including species richness, phylogenetic  diversity and abundance. We collected ants in all 155 plots of the BrazilDry project, a  biodiversity experiment established in the Açu National Forest. The plots contain one,  two, four, eight and 16 plant species with varying compositions and a gradient of  facilitation. Our results suggest that plant diversity is the main mechanism responsible for  the richness and phylogenetic diversity of ants in the BrazilDry experiment. Possibly the  result comes from a bottom-up effect in the trophic chain, in which plants provide  essential resources for the ants, increasing their diversity. In chapter four, we examine  the correlation between the distribution of animal diversity in the Caatinga among five  taxonomic groups: birds, reptiles, amphibians, mammals and ants. We also tested the  influence of abiotic factors on the distribution of diversity within these groups. To do this,  we retrieved species distribution maps and climate variables from online databases.  Pearson's correlations were used to test the overlap of diversity between the groups, and  multiple linear models were used to test the relative importance of abiotic factors in  organizing the diversity of these groups. Our findings indicate that animal biodiversity in  the Caatinga largely overlaps, but the response to abiotic conditions varies according to  the taxonomic group analyzed. With this thesis, we have filled important gaps in ant  diversity, distribution, abiotic determinants and responses to tree richness. In addition, we  describe the abiotic determinants and the degree of overlap of animal diversity in the  Caatinga.

Ecological interactions involve all living beings and ecosystems we know. In reef  systems, corals and algae are important organisms that interact with each other in  positive, negative and neutral interactions, and they can be influenced by top-down  (mediated by consumers) and bottom-up (mediated by producers) effects. Reefs and  their complex interactions are threatened by local and global impacts, which can  change their patterns and outcomes of interactions. In this thesis, we explored coral algal-herbivores interactions under different perspectives. In Chapter I, we did a  systematic review involving the last 20 years of studies (2002-2020) and we asked: i)  where these interactions have been explored globally; ii) what are the main organisms  involved; iii) the most frequent outcomes; iv) the effects of herbivores over the  interactions; and v) the effects of climate change. We found that i) Pacific and  Caribbean regions concetrate 86% of interactions; ii) the main organisms involved are  massive and branching corals, and macroalgae and turf, with some variation among  regions; iii) adults corals are mostly harmed by algae suffering sublethal damages,  while juvenile corals can be both harmed or benefitted mainly by recruitment; iv) most  of the studies evaluate the effects of herbivory in indirect ways (e.g. abundance  correlations), with few experimental efforts; and v) the effects of climate change were  explored in only 10% of studies, negatively affecting coral recruitment and causing  sublethal effects, and reducing algal abundance. In Chapter II, we explored coral-algal herbivore interactions in tropical reef in Brazil, evaluating i) their historical  abundances; ii) the current frequency of coral-algal interactions; iii) the outcome of these interactions; iv) how the warming ocean can influence coral-algal interactions,  and v) if different herbivore could mediate coral-algal interactions in the current and  future scenarios of warming. We found that i) benthic cover is stable in the last  decade, reflecting older registers, with algal dominance (60%) and low coral cover  (5.6%), in a scenario that does not seem related to local biomass of herbivores fishes;  ii) coral-algal interactions are frequent and 96% of them involve the coral Siderastrea  stellata interacting with turf; iii) the majority of interaction lead corals to decrease in  phootsynthetic efficiency but this vulnerability varies among coral species; iv) coral algal interaction are equally harmful for corals in current and future scenarios of ocean  warming, carrying among species; v) the dominant macroalgae is little consumed by  different herbivores, regardless of temperature, which indicates low effects of  herbivores over coral-algal interactions. In Chapter III, we explored the effects of iron  enrichment over algal palatability, evaluating different iron concentrations (control,  100 µg/L, 300 µg/L, 900 µg/L) in three exposure times (days 0, 13/14 and 26/27), and  we found that different iron concentrations did not affect algal palatability, bus we  observe higher consume in the middle exposure time, likely due to balance between  chemical defenses and algal integrity. Thus, we explored coral-algal interactions,  evidencing some global patterns and describing regional patterns that challenge  current paradigms in ecology that herbivory is the main factor mediating coral-algal  interactions.

Most of the organic matter (OM) synthesized in ecosystems turns into litter. A set of physiological, ecological, evolutionary, and environmental mechanisms act on both the synthesis and degradation of OM making it very diverse, concerning its chemical and physical traits, which play relevant functional roles in determining the dynamics of litter degradation in ecosystems. The functional litter diversity/heterogeneity has consequences through litter-mixing effects (LMEs) on the decomposition and nutrient cycling in terrestrial and aquatic ecosystems. However, several gaps regarding both the causes and consequences of litter diversity for ecosystem functioning remain poorly understood. Thus, we aimed to assess the causes (Chapters 1 and 2) and consequences (Chapters 3-5) of litter diversity/heterogeneity in decomposition and to understand their effects on the occurrence, direction, and magnitude of LMEs. In Chapter I, we evaluated the LMEs at the intra-specific level in aquatic and terrestrial ecosystems, using flower and leaf litter of Tabebuia aurea (Silva Manso) Benth. & Hook. f. ex. S. Moore as a model. Our results indicate that the differences in functional litter traits between flowers and leaves resulted in litter-mixing effects, mostly synergistic effects, associated with complementarity mechanisms. Since flower and leaf litter seems to be a labile and refractory litter, respectively. Our results indicate that the litter diversity at the intra-specific level between different organs could be important in mediating LMEs, and these effects were stronger in terrestrial ecosystems. Our results suggest a feasible secondary role for flowers in after senescence in the OM cycling. In Chapter II, we tested the generality of flower litter as a labile organic matter and leaf litter as a refractory organic matter in terrestrial ecosystem. Specifically, we evaluated patterns and predictors of flower and leaf litter decomposition at the intra- and inter-specific levels for 29 species. Our results indicate that flower litter had a higher concentration of N, P, and K, while leaf litter had higher density, Ca, Mg, and Na. And that the functional traits, leaching rate, P, Ca, Mg, and Na, predicted the litter decomposition of both litter types. Overall, the differences observed in decomposition rates and functional traits between litter types indicate differences between flowers and leaves in the potential diversity effect on decomposition. In Chapter III, through a meta-analysis, we evaluated how the individual response of species in mixtures can alter the occurrence, direction (i.e. positive or negative), and magnitude of LMEs. Differences in functional traits between species and litter identity were the main factors mediating LMEs in both terrestrial and aquatic ecosystems. In Chapter IV, also through a meta-analysis, we evaluated the complementarity effects between labile (i.e. higher C: nutrient ratio) and refractory litter (i.e. lower C:nutrient ratio), testing the idea that labile species accelerate the decomposition of refractory species, while refractory species decrease the decomposition of labile species. Our results indicate that labile species showed additive responses when interacting with refractory species; while refractory species had antagonistic responses when interacting with labile species. When evaluating LMEs considering ecosystem type, presence or absence of decomposers, and stage decay, we observed a preponderance of antagonistic effects for labile species. When directly evaluating the effects of labile and refractory species, we found patterns that challenge the current direction in the effects of complementarity between litter with different decomposability. In Chapter V, we evaluated how the litter interaction for different temporal dynamics, resulting from different phenological patterns, can affect the LMEs. Specifically, we evaluated how an intermittent or seasonal input of litter affects the occurrence, direction, and magnitude of LMEs in aquatic and terrestrial ecosystems. We did not find clear patterns in the effect of litterfall inputs on decomposition, but we observed a preponderance of LMEs in the aquatic ecosystem, probably related to the different dynamics and nutrient concentrations in its ecosystem due to the experimental conditions. The results obtained in this thesis contribute to advancing knowledge of LMEs, specifically to evaluate how the causes and consequences of litter heterogeneity may be important in mediating the occurrence, direction, and magnitude of LMEs.

Sexual selection benefits traits that increase reproductive success and often determines differential resource allocation between male and female sex components. In plants, competition between males leads to increased investment in male function, and may even result in disinvestment in female function. The Asteraceae family has specialized inflorescences, the floral chapters. In these structures, small flowers are condensed together sharing the same receptacle. The number of flowers present in the floral chapter can vary widely among species. Additionally, some groups have evolved chapters with morphological and functional dimorphism among flowers, which may result in distinct sexual roles. In this thesis, our goal was to understand the history and evolutionary significance of variation in the number of flowers per chapter, as well as to estimate its importance in determining inflorescence architecture and masculinization. The thesis is divided into three chapters. In the first, we reconstruct the ancestral states of flower number and chapter architecture along a calibrated phylogeny. We find strong evidence that the common ancestor for the entire family possessed homogamous inflorescence with few flowers (~ 12). Heterogamy evolved several times independently, although a larger number of reversions to the homogamous condition were observed in the phylogeny. The number of flowers per chapter is an extremely plastic and poorly conserved trait. Chapters with more flowers are more likely to be heterogamous. In the second chapter, we found that chapters with higher flower numbers invest more in male function by increasing pollen production per chapter. We found no evidence of disinvestment in egg production in more flowered chapters. Therefore, we can conclude that in the family Asteraceae, chapters with more flowers are not merely more numerous copies than those with fewer flowers. Finally, in the third chapter we will test the influence of herbivory pressure on flower chapter masculinization. We found that species under higher herbivory pressure tend to have more flowered capitula, with more ray flowers, which suggest energy allocation for outrossing.

The preservation of biodiversity and the provision of ecosystem services increasingly depend on environmental conservation on private lands. There are many studies demonstrating the capacity of private protected areas to conserve biodiversity. Private conservation has been growing globally, but its management characteristics levels of use and protection differ between countries. Despite these differences, these areas have in common the role of important actors involved in financing and promoting actions for environmental protection. Our aim is to understand possible political and social context factors, in the national and regional scenario, that contributed to the dynamics of creation of Brazilian Private Natural Heritage Reserves (RPPNs). We applied an online questionnaire to owners and managers, collected and analysed data focusing on motivations, difficulties, support received and actors involved in the process of creating RPPNs. Our results showed that around 70% of the owners' motivations were mainly conservationist, although not exclusively so. This was a pattern, independent of region or biome, scope of creation (federal, state or municipal) or type of owner (individual or company). With regard to difficulties, 58% experienced difficulties, regardless of time, the majority of which were bureaucratic (75%), differing between region and biome. Only 57% of landowners received support, 67% from Non-Governmental Organizations and 31% from state governments. For landowners, technical support was more significant than financial support. The creation of RPPNs can be attributed not only to laws or specific policies to encourage it, but also to the altruism of the landowners. The social interactions existing in a region or within a group of people seem to have determined the dynamics. Legislation enacted at different levels of government in combination with socio-economic trends create the conditions for establishing RPPNs. Projects and public notices encouraging the creation of new RPPNs, with the predominant participation of NGOs, were crucial to the emergence of new RPPNs.

The Brazilian seasonally dry tropical forest (Caatinga) is a semi-arid environment marked by a long dry period and a short rainy period that results in a great fluctuation in the conditions and resources for fauna. Medium to large mammals are usually the group most threatened by human activities, and thus are considered indicators of biotic integrity of the environment. Thus, understanding their ecology is essential for the effectiveness of management and conservation strategies, especially within protected areas, which, despite being the main strategy used for the persistence of biodiversity, are still scarce in the Caatinga. The objective of this work was to investigate the ecology of the mammal community in Furna Feia National Park, and how seasonality influences the ecology parameters of the community and the species. More precisely, we characterized the richness, frequency of records, composition, simple occupancy and activity pattern of the species and their relationship with seasonality. We collected the data throughout the rainy and dry seasons of 2018, using camera traps at 44 and 40 sampling points, with an effort of 2267 and 1639 camera-days, respectively. Rarefaction curves, circular statistics, and occupancy models were some of the analyses used to characterize the community and its seasonal patterns. We obtained 485 records of 11 species of mammals distributed in six orders and nine families, including two species threatened with extinction in Brazil and/or by the IUCN (Leopardus emiliae and Herpailurus yagouaroundi) and the first photographic record of free-living Dicotyles tajacu for Rio Grande do Norte. Species with the highest frequency of records include Subulo gouazoubira, Euphractus sexcinctus and Sapajus libidinosus. Meanwhile, Leopardus pardalis, H. yagouaroundi and D. tajacu were the least recorded. Regarding the activity pattern, S. gouazoubira changed from the rainy to the dry season, from diurnal to nocturnal. While the other species analyzed seem to distribute their activities to avoid the hottest times of the day, especially during the drought. The species richness did not change, but relative abundance was higher in the wet than in the dry season for most species, except for D. albiventris, which showed the opposite trend. Some species exhibited no variation in occupancy and detectability, while others such as S. gouazoubira were more detected and expanded their occupancy in the wet season. This work represents the first systematic survey with camera trap for an important UC in the Caatinga, and the results on seasonal and circadian activity rhythm will improve the understanding of animal ecology and the mechanism of permanence in seasonally dry environments.

Co-management is a system of resource governance characterized by the participation of local stakeholders in decision-making processes. Several factors affect resource users participation in management, such as material assets, education, active involvement in management, and participation in community associations. A case study was conducted based on the reconstruction of past fishing catches from fishermen's memories, in order to discuss the potentials and limitations of using scientific knowledge and local ecological knowledge. This chapter aims to understand if the type of knowledge (traditional or scientific) influences the fishermen's participation in the co-management process. It is expected that fishermen prefer the use of their own knowledge, associated or not with scientific knowledge, rather than the exclusive use of scientific knowledge. The fishery reconstruction was developed using data from four fisheries, three located in the northeast (Rio Grande do Norte) and focused on the capture of Lutjanus analis (cioba), Coryphaena hippurus (dourado), and Opisthonema oglinum (sardinha), and one located in the southeast (Rio de Janeiro), focused on the capture of Mugil liza (tainha). A total of 131 interviews were conducted in the Ponta do Tubarão State Sustainable Development Reserve (RDSEPT/RN) and 74 in Araruama (RJ) using a semi-structured  questionnaire. The questionnaire was used to estimate the catch of the species for the last five decades and to assess the level of fishermen's participation in fisheries management. The decline in the average catch of dolphinfish and sardine between 1980 and 2020 was observed, as well as in the total catch of mullet between 1970 and 2020. In addition, most of the fishermen interviewed expressed that they prefer management decision making to be based on a combination of scientific knowledge and local ecological knowledge. The analysis of the results of this case study makes it possible to identify the main benefits and limitations of using scientific knowledge and local ecological knowledge in the management process. 

Climate change-induced redistribution of fish stocks is anticipated to have global implications for marine fisheries. For instance, it is expected that fish catch potential will increase in higher latitudes, while declining in tropical regions. However, how different countries and fishing gears will respond, and whether they will be able to redistribute their catches spatially in response to these changes remains unknown. We built fisheries distribution models and projected their occurrence globally, across 82 countries and 13 fishing gears in 2100, under two climate scenarios: the low and high levels of greenhouse gas emissions. Globally, fisheries occurrence is expected to significantly increase at the poles, whereas vulnerable fishing-dependent tropical regions like the Indo-Pacific and Western Africa are projected to experience significant declines. We also show that countries already engaged in polar fishing are likely to be the primary beneficiaries of the newly available and favorable fishing grounds, with eventual benefits of climate change being limited to a select few nations, resulting in both winners and losers. East Asian and Pacific nations with fleets predominantly composed of drifting longlines experienced negative impacts, whereas European countries equipped with trawlers and other polar gears reaped benefits. Our findings emphasize the importance of prioritizing the low-emission scenario to reduce the increasing disparities in the future of marine fisheries, given that changes in occurrence were more than twice as high under the high-emission scenario.

The increase in plastic production and consumption in recent decades has been accompanied by a proportional increase in its disposal and accumulation in the environment, particularly in its potentially most polluting form, the microplastic (particles <5mm). The presence of this emerging pollutant in the environment invariably results in its interaction with organisms, potentially generating multiple effects on wildlife and human health. The scientific community has invested significant efforts to better understand such effects. However, some aspects are still unclear, while others are underexplored, especially at broader ecological scales involving ecosystem approaches and multiple levels of biological organization simultaneously. Studies in this context offer necessary advances to roaden the understanding of the threat of plastic pollution. Therefore, this thesis is organized into three chapters that investigate the plastic contamination in aquatic organisms, using fish as model organisms, and evaluate the potential effects of this contamination on physiological, functional and ecological aspects. Additionally, we will address the issue of food security, related to human consumption of potentially microplastic-contaminated marine species. In the first chapter, we tested whether exposure to microplastic can affect the health and performance of freshwater fishes, assessing biological factors from molecular to organismal level. In the second chapter, we conducted an in-situ experiment to test whether the presence of plastic in the environment influences the herbivory pressure of reef fishes, and consequently, their ecosystem function. And in the third chapter, we seek to estimate the degree of contamination in commercially relevant species in NE Brazil in order to point out the ecological and socioeconomic impacts of plastic pollution. With this thesis, we hope to contribute to the construction of a broader and more solid foundation regarding the impacts of plastic and microplastic on aquatic organisms and ecosystems.

Reefs and other marine ecosystems face significant threats from human impacts, including pollution, poorly regulated tourism and global climate change. Marine Protected Areas (MPAs) stand out among the most important strategies for marine conservation. In Brazil, the Fernando de Noronha archipelago (FN) is protected by two MPAs: a no-take area and a multiple-use area. However, the archipelago has been experiencing increasing impacts due to the expansion of tourism and human occupation, and climate change. In this context, the main objective of this thesis was to assess the 

role of MPAs in mitigating multiple local and global impacts on marine environments in FN. In Chapter 1, we investigated the presence of marine litter on the beaches of FN and its distribution related to oceanographic factors and tourism. We found a higher abundance of plastics in uninhabited areas on the windward side, despite being within the no-take area, a more restricted MPA, while on the leeward coast, near urban areas and within a less restricted MPA, there were more disposable plastics and cigarette butts. In Chapter 2, we investigated the temporal dynamics of benthic organisms in a tide pool and observed that temperature anomalies were the main factor affecting coral health and their endosymbiont communities. Although seasonal burial caused high temporal variability in benthic cover, it did not affect coral health. The number of tourists diving in the area also did not influence coral health, indicating that proper management can reduce tourism impacts. In Chapter 3, we mapped and quantified marine pollution in FN (nutrients, metals, microplastics, sterols, and polycyclic aromatic hydrocarbons - PAHs), characterizing their sources and evaluating their impacts on reef communities. We detected pollutants both in the multiple-use and in the no-take area. While nutrient concentrations in the water were in accordance with legislation in most samples, effluents from wastewater treatment plants did not meet legal standards. The isotopic signature of macroalgae indicated the presence of sewage-derived nitrogen throughout the multiple-use area, and nutrient-enriched areas showed distinct benthic communities with higher algal biomass. Sediment analysis revealed generally low levels of PAHs and fecal sterols, except in samples from Porto. We observed relatively high metal concentrations in sediments at some sampling stations, which may be related to both anthropogenic sources and the volcanic origin of the archipelago. Microplastics were found in all sediment and water samples, from the multiple-use and the no-take area. We emphasize the urgent need to improve wastewater management to protect the marine ecosystem in FN, promoting its resilience facing climate change. We also highlight the vulnerability of the no-take area, with pollutants originating from the multiple-use area on the leeward coast and pollutants transported by currents from distant sources on the windward coast. The information generated by this work will serve as an important reference for monitoring initiatives and improving management strategies for conserving FN and other MPAs.

Feather molt in birds is a naturally occurring process due to the wearing down of old feathers. For it to occur, a large amount of energy is required, so it does not usually coincide with other events in the bird's life cycle such as breeding and migration. It is common for the moulting period to occur at a time of year when there is a greater supply of food. Factors such as primary productivity of the region and rainfall can directly affect resource availability. The Passerine order is the largest order of the bird group, and several ornithological studies are carried out with representatives of this group due to its great diversity. Our study was carried out with passerines from a restinga area, typical vegetation of the Atlantic Rainforest, which houses peculiar vegetation formations and little is known about its avifauna. Based on this, we sought to understand whether there is overlap between the moulting period and breeding, and whether there are differences in the moulting patterns due to differences in the diets of these passerines. We used a database of bird captures at CLBI, Parnamirim, RN formed between 2010 and 2014. We counted presence or absence of wing, tail, body and simultaneous wing, tail and body moulting. We also counted presence or absence of brood patch. We separated the species into four diet groups: fruit, invertebrate, invertebrate/fruit, and omnivorous. We ran GLM models to analyze which variable best explained the variation in moult frequency, and simple linear regressions to analyze the relationship between moulting and the variables studied. Our results showed that the best variable that explained the variation in moult frequency was NDVI, as a temporal variable, and the moult frequency was different between flight feathers (rems and retrizes) and body feathers, with these types of moults configuring the most explanatory biological variable. We also saw that the different diets did not influence the frequency of moulting, and that the weak overlap found between the moulting period and reproduction occurs only as a temporal coincidence, since the peak of reproduction occurs in February and the peak of the moulting period occurs in May.

Urbanization is a major driver of natural habitat reduction and fragmentation, and it has been shown that these impacts can influence species richness. However, how different components of diversity are influenced by urban intensity, patch size, and isolation between patches has not yet been mechanistically investigated. In this context, urbanization gradients are ideal for assessing how species respond to these impacts, and also allow us to better understand how local and regional changes in habitat quality influence diversity components such as: species abundance distribution (SAD), total community abundance (N), and intraspecific spatial aggregation (Agg). Here, we evaluate how two different categories of urbanization intensity (urban squares and protected areas), patch size, and its connectivity influence bird diversity patterns at various scales. To assess scale-dependent processes, 24 plots were allocated, each subdivided into 4 subplots, totaling 96 points, which were visited five times during the dry season. In these same plots/subplots local and regional environmental features were assessed. A significant reduction in species richness and abundance was observed with increasing urbanization, and this reduction was evident across all scales analyzed. However, the effect of urbanization was even stronger at plot than subplot scales, indicating a scale-dependent effect of urbanization. Furthermore, both local and regional variables, including vegetation cover and structural connectivity, were important determinants of bird diversity patterns. Thus, it is necessary to conduct practices that can reduce the intensive impact of urbanization. An example to be highlighted are actions that include more forested squares, as well as planting trees around these squares and forming ecological corridors, aiming to connect parks and green areas with urban squares.

Marine Protected Areas (MPAs) are important mechanisms for the conservation of reef environments, reducing local impacts such as pollution and overfishing, and helping corals survive to global bleaching events. However, many of these areas do not consider climate change in their planning, which may reduce the future protection of corals given the likely change in these species’ distribution. We evaluated the representativeness of zooxantelate shallow-water scleractinian corals in the categories and jurisdictions of the current MPAs network in Brazil. We used gap analysis to investigate changes in future MPA representativeness along the Brazilian province, under the most extreme scenario predicted by the Intergovernmental Panel on Climate Change (IPCC, RCP 8.5). We observed that 21 coral species are included in sustainable use and 19 in strict protection MPAs, and there are no predicted differences in coral assemblage composition between categories or jurisdictions. MPAs are located where there is highest occurrence probability for corals in current and future projections, being mostly represented by the sustainable use categories. As environmental conditions change, subtropical regions will experience increases in coral occurrence probability and these may turn into key areas for coral conservation in the future. Therefore, adopting actions which incorporate climate change in the planning of MPAs may contribute to the survival of these organisms.

Lack of knowledge about taxonomy and population structure of conflict-targeted fish species hinders the correct management of its stocks. The origin of such conflicts in Marine Protected Areas (MPA) are worth investigating in order to propose effective resolutions. With this in mind, this work makes a systematic review of the variables involved in the origin of fishing conflicts in MPAs around the world and investigates the population structure of a species target of conflict in a Brazilian MPA, the scaled-sardine Harengula sp.. In the first chapter, searches were carried out with specific keywords in the Scopus platform, totaling 269 documents analyzed. In the first screening performed by reading the abstracts, 114 articles were selected for full reading, from which 58 were included in the analysis. The main criteria for the selection of articles was the presence of some type of fishing conflict within an MPA. It was found that the main cause of conflict is illegal fishing, followed by a feeling of exclusion from the MPA management and creation process and conflict between fishermen and conservationists. Artisanal fishing, as well as artisanal vessels and artisanal gear, were the most mentioned in the conflicts, indicating that traditional fishermen are the most involved in fishing conflicts. The most conflicting type of management was the governance in sustainable use MPAs. In the second chapter, we used sequences of the mitochondrial DNA control region of 117 individuals from the states of Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Bahia, Espirito Santo, Rio de Janeiro, São Paulo, Santa Catarina, and the islands of Fernando de Noronha (FNO) and Abrolhos (ABR). The lineage delimitation, gene flow and molecular variance analyzes indicated three populations of scaled-sardine along the Brazilian coast: FNO, north, and south clusters. The population in FNO, where the fisheries conflict is stronger, is stock that is diverse and distinct from the one on the northeast coast (including ABR), and the one in the southeast and south of Brazil. These results indicate that temperature and depth act as barriers to gene flow. This work provides a broad view of the origins of fisheries conflicts in marine protected areas around the world and contributes to the understanding of genetic aspects of a target species of a fisheries conflict in a protected area in Brazil.

Currently, there’s still a knowledge gap on how climate change will affect marine ecosystems and organisms. This knowledge gap is also valid to economically important sectors, such as aquiculture, which cultivates marine organisms. One of the most cultivated organisms in aquiculture is the seaweeds, which the production has been increasing annually, being one of the most promising sectors of aquaculture. The Ecological Niche Modeling (ENM) has currently been applied as a tool to predict the future distribution of species with economic potential regarding environmental and chemical impacts driven by climate change. In this context, this study aimed to evaluate how the projected scenario of future climate change (RCP 8.5) will impact the cultivation of the seaweed Gracilaria birdiae in the Brazilian coast based on the ENM. The modeling was carried out by integrating the MaxEnt algorithm to the RStudio software. The species occurrence data were obtained from the literature. Bioclimatic data were acquired through the Bio-ORACLE database. To validate whether there were significant differences among site suitability at each period, a Friedman test was also performed. The results revealed that the species site suitability will expand in the future and the species distribution was not limited by the temperature. Studies have reported that the genus Gracilaria exhibits a broad range of temperature tolerance, which may explain why the increased superficial seawater temperature will not affect G. birdiae in the RCP 8.5 scenario. In conclusion, the seaweed Gracilaria birdiae shows a great potential for seaweed cultivation in the coast of Brazil, which could lead the country tobecome a major producer of this species.

Understanding the spatial organization of species in megadiverse regions, such as the Neotropics, has been a challenge that has fascinated researchers since the first naturalists of the 19th century. We know that the distribution of species is not a random process, and to interpret how they are organized, occurrence maps are essential to understand the distribution patterns of biological diversity. Due to the geographic distributions of many species being little known and full of gaps, a problem known as the Wallacean deficit, which constitutes a huge bottleneck for effective conservation planning. With the objective of contributing to the advancement of knowledge and minimizing the Wallacean deficit on amphibians - a diverse group of vertebrates, threatened and little studied in semi-arid regions - we conducted here a systematic review of primary research and presented the first compilation of distribution and distribution data. Detailed maps for all amphibian species (anurans and caecilians) recorded within the limits of the Caatinga, Northeastern Brazil. All species had their extent of occurrence known in the Caatinga mapped, accompanied by a description of their distribution and conservation status. We provide data on patterns of species richness distribution, sampling gaps, levels of endemism and we provide information on the distribution of each species in the Neotropical region. We created an amphibian database from the direct analysis of 29.831 occurrence records, with respective vouchers, within the limits established for Caatinga. We recorded 121 amphibian species in the Caatinga, belonging to 18 families. In addition to species that occur in other natural regions, 19 amphibian species are endemic (16,53% of the total species). The richest family was Hylidae with 46 species (38,02% of the total species), followed by  eptodactylidae with 31 (25,62% of the total species). Our results support new ecological studies and herpetofauna inventories, and also contribute to decision making regarding priority areas for amphibian conservation in the Caatinga of Northeast Brazil. 

In the decade of ecosystem restoration, it becomes necessary to reverse the advance of degradation of natural environments, aiming at sustainable development and ensuring human well-being. To achieve this goal, we must think about the restoration of dryland environments that represent 47% of the land surface, such as the Caatinga, a Brazilian semi-arid ecosystem that covers an area of approximately 912,000km². To scale up restoration projects in this biome, we must understand which species and community compositions can ensure greater success in restoration projects. The aim of this work was to identify species and compositions that show good potential for restoration in the Caatinga. We analysed a five-year period of the first cohort of the BrazilDry experiment located in Açú National Forest (Rio Grande do Norte, Brazil). Using analyses of variance with Tukey's a posteriori test, we tested which species and communities, exhibit: (1) stability in first cohort mortality (species only) and percent survival, (2) mean height, (3) mean annual growth, (4) photosynthesizing biomass production, and (5) diameter above ground (DAS). For the species, all the investigated variables were significant with values of P=>0.001. We found that only one species showed average survival below the stipulated (16%) after five years of planting and more than half show some stability in the cohort. Most species presented height and DAS within the assumed ranges for the work (1 to 2m and 10 to 20mm, respectively), besides presenting, in general, an annual growth between 0m to 0.5m. M. tenuiflora was the highlight in the production of photosynthesizing biomass and DAS, with values exceeding 200g and 30mm, respectively. Regarding plant compositions, only survival and photosynthesizing biomass differed with P=>0.001. Only one composition is not above the 16% survival range. The monoculture of M. tenuiflora differs from all other  compositions in the production of photosynthesizing biomass. The stability in the survival curve of the species presents some stability between 2-4 years due to the technique of root extension. The height and growth show satisfactory results, even with the limitation of their development caused by the dry period, competition with exotic herbaceous species and the capacity for regrowth. The photosynthesizing biomass and DAS are driven by
species diversity, however, in its establishment and growth phase competitive interactions may prevail. This work brings a selection of native species and communities that perform well over 5 years restoration in Caatinga, presenting characteristics that define their potential in the recovery of degraded areas. 

The Atlantic Forest is a global biodiversity hotspot, and it is essential to comprehend the ecological and evolutionary processes responsible for shaping highly diverse environments. This comprehension allows a theoretical advance on the factors raising diversity, but also a practical advancement increasing the effectiveness of the spatial prioritization of areas to be protected, contributing to the conservation of hotspots. In the Atlantic Forest, Myrtaceae stands out as the most diverse woody plant family (691 species) and is an excellent model for studies because its richness patterns are representative of other taxa. Thus, this work had two objectives: (1) to map the evolutionary diversity metrics of Myrtaceae in this domain in order to understand the evolution of the Atlantic Forest flora, and (2) to assess whether the current network of conservation units in the Atlantic Forest is representative of the evolutionary diversity of the domain. We used information from articles that conducted studies in floristics represented on two databases, Caaporã and NTT, which were reviewed before analyses to correct potential species occurrence and/or nomenclatural errors. The records used summed 492 Myrtaceae species occurring in 1282 sites. The sampling of geographic space showed good coverage and robust representation of the environmental space of the domain. We found that evolutionary hotspots are concentrated in the southern portion of the Atlantic Forest, in southern and southeastern Brazil. On the Brazilian coastal regions, from the south to the northeast, are the areas with higher concentration of derivate lineages and species that are more closely related to each other, while in the interior of the southern region, the deepest lineages are concentrated. The existence of temporally stable climatic refugia to the south of the domain, as well as the history of colonization and expansion of this family in the South American continent, which begins in the south and expands to the northward, may explain the concentration of older lineages in the south of the domain. In Santa Teresa/ES and in the coastal forests of southern Bahia (Ilhéus/BA) we recorded the greatest diversity of phylogenetic endemism, sites that harbor unique lineages, restricted to these regions. The patterns of phylogenetic diversity of Myrtaceae described here corroborated patterns already described for other terrestrial taxa, such as birds and arthropods, which reinforces the use of Myrtaceae as a model group for macroecological and macroevolutionary analyses in the Atlantic Forest. The current network of protected areas in the Atlantic Forest covers part of the evolutionary history exhibited in Myrtaceae for the metrics of phylogenetic endemism and mean root distance. However, this network did no protect all variation on phylogenetic variability and diversity. This result urges future studies focusing on the indication of new areas to preserve all evolutionary components. Conserving evolutionary potential is a way to increase the chances of taxa responses to the scenarios of environmental changes predicted for the future. The results produced here should be included in spatial prioritization analyses. 

The Caatinga is characterised by a semi-arid climate, high temperatures, high evaporation rates and geological conditions that favour greater soil fertility and rapid plant growth in the rainy season, but also a greater accumulation of salts in the soil, which can impair plant development. To increase the efficiency of restoration in degraded areas, studies of plant responses to both soil fertility and salinity are necessary. This study was conducted in a restored area of Caatinga and aims to: 1) Characterize the levels of salinity and fertility of the soil in this restored area; 2) Test how salinity and fertility contribute to the success of restored communities, in terms of  survival; 3) Test how different compositions of restored communities could influence soil parameters after 5 years of restoration. The study was conducted at FLONA de Açu-RN, in an experiment established 2016 in a degraded Caatinga area. The site was divided into 155 plots, where native seedlings were planted with five different levels of richness (1, 2, 4, 8 and 16). The work was carried out in all monocultures and in the plots where all tree species were planted together (16 species). In these plots soil samples were collected and analysed for fertility and salinity parameters that were calculated according to the Embrapa methods manual. To test whether soil salinity and fertility characteristics (explanatory variables X) influence the survival of tree communities (response variable Y), we used Mixed Models in R software, observing how the continuous parameters of salinity, fertility and the two levels of vegetation diversity (1 and 16 species) affect the survival of planted tree species. To test whether the species composition of monoculture and polyculture (explanatory variable X) has any effect on soil parameters (response variables Y) a MANOVA was performed using the soil parameters that were not previously correlated. The results showed that the soils are not saline and that several plots show good fertility. For salinity-related parameters, increasing Electrical Conductivity reduced species  survival in mono and polycultures, whereas high potassium (K) availability generated higher survival rates in the plots. For fertility parameters, high availability of potassium (K) was also observed in higher survival plots, while high availability of Organic Matter generated lower survivals. No significant difference was found in soil arameters for both salinity and fertility in relation to monocultures and polycultures in these first 5 years of restoration demonstrating that tree species, in this space of time, are not yet able to alter the quality of the soil. The work also demonstrates that a greater amount of potassium in the soil can lead to an increase in seedling survival in Caatinga restoration programmes.

Our objective was to estimate the occupancy of endemic and threatened passerines in the Atlantic Forest north of the São Francisco River, Brazil, and to analyze the factors that enhance their distribution. The occupancy of bird taxa was modeled and used to predict the direction of response of eight covariates based on prior knowledge of bird ecology. A priori, the covariates measured are expected to represent the key habitat characteristics for the species (i.e. temperature, precipitation, forest area, elevation) or anthropogenic effects (here, distance from roads and the urban perimeter, for example) to be harmful the birds in focus, based on the hypothesis that anthropogenic factors would have a negative effect on occupancy in CEE, while habitat covariates would have positive effects on the occupation of rare birds. We used data available in the literature, online databases, ornithological collections and from researchers in the region to estimate the parameters using single-season occupancy models. The occupancy of the grid was best described by two variables: altitude and forest area. The detectability was affected by the trend of linear effort over time, which indicates that the increase in the sample effort was important for most of the studied taxa. Our study provides robust information on the influence of covariates studied on endemic and threatened passerines and is the first study to provide data on large-scale anthropogenic effects in occupancy for most endangered and endemic species in this endemism center. The data indicated that the occupancy and detectability of the species was influenced by single variables of greater weight, but that possibly act in conjunction with multiple factors. The generated maps provide information that can be useful in management and action plans for the conservation of the areas where this species occurs, which favors the allocation of resources. Understanding the covariates studied can also potentially reduce the risk of worsening bird losses through policy measures for habitat management in the region.

Increased greenhouse gas concentrations in the Earth’s atmosphere have resulted in an atmospheric and oceanic warming. Global warming has caused climate change and sea level rise worldwide. Estuarine salinization is expected due to the sea level rise, longer droughts, and estuary warming. In addition to these global changes, a decrease in oceanic pH has been recorded because of increased dissolved carbon dioxide (CO 2 ) in seawater, an environmental disturbance termed ocean acidification. Fluorinated gases emitted into the atmosphere, in addition to being greenhouse gases, lead to a stratospheric ozone depletion, resulting in a higher harmful solar radiation on the Earth. Primary producers in coastal ecosystems such as mangrove swamps can be negatively affected by these global changes. Thus, in this thesis, we investigated the physiology of the mangrove macroalgae Bostrychia montagnei and Bostrychia calliptera from tropical and subtropical populations after being subjected to global change experimental conditions. The genetic divergence between tropical and subtropical macroalgal populations was also investigated using mitochondrial (COI-5P) and plastidial (rbcL- 3P) DNA markers. The results from our investigation are shown in five scientifi articles, whose main results are briefly described hereafter. In the first article (doi.org/10.1016/j.jembe.2022.151740), we reported that tropical macroalgal populations are genetically divergent from subtropical macroalgal populations, based on the COI-5P marker. We also demonstrated that macroalgae from both climatic niches are tolerant of decreased pH (7.6 and 7.2) by CO 2 enrichment of the seawater (ocean acidification), increasing their growth under decreased pH treatments due to increased CO 2 availability for photosynthesis. Tropical B. montagnei increased its polysaccharide and allophycocyanin content at pH 7.2, and subtropical B. montagnei increased its low molecular weight carbohydrate content at pH 7.2 as well. In the second article (doi.org/10.1016/j.marenvres.2022.105662), we reported that tropical and subtropical B. montagnei and B. calliptera decreased their growth and photosynthetic performance under simultaneous increase in temperature and salinity. We evidenced that macroalgae synthesized proteins, carbohydrates and antioxidants to tolerate detrimental temperatures and salinities, as well as they adjusted their pigment contents (phycobiliproteins, carotenoids, and chlorophyll a) for efficient light-harvesting under thermal and saline stress. In the third article, we observed that tropical B. calliptera and B. montagnei decreased their photosynthetic performance under rising salinity  (salinization in tropical estuaries influenced by semi-arid climate). Bostrychia montagnei showed osmotic acclimation by synthesizing and accumulating organic osmolytes dulcitol and sorbitol under rising  alinity, whereas B. calliptera mainly synthesized and accumulated dulcitol. Sorbitol was only synthesized by B. calliptera at salinities of 37.1, 47.1, and 57.3 S A , as a trace compound. Between species, B. montagnei showed a greater photophysiological tolerance to the salt stress by synthesizing and accumulating both dulcitol and sorbitol, since sorbitol is a physicochemically better osmolyte than dulcitol. In the fourth article, we registered that under increase in photon flux density (increased solar radiation on the Earth due to stratospheric ozone depletion), tropical B. calliptera and B. montagnei exhibited a lower photosynthetic performance. We also recorded a photodamage on the pigment content of B. montagnei under light stress, whereas in B. calliptera a photodamage was only observed on its chlorophyll a content. In both species a photodamage was also registered on their mycosporine–like amino acid (photoprotective compounds) contents under increasing light stress. More pronounced photodamage was observed on B. montagnei. This lower tolerance of B. montagnei to the light stress may explain its preferential occurrence at more shaded microhabitats, as documented in the scientific literature. In the fifth article, we evidenced that tropical and subtropical B. montagnei and B. calliptera increased their dulcitol and sorbitol concentrations under decreased pH by CO 2 enrichment of the seawater. Thus, these polyols also have an energetic function. The carbon content in the macroalgae also increased under ocean acidification. Tropical and subtropical B. montagnei and B. calliptera increased their dulcitol and sorbitol contents under rising temperature and salinity. This demonstrates that these polyols also have a thermal protection function in Bostrychia species. In conclusion, our data support that tropical and subtropical  opulations of B. montagnei and B. calliptera are genetically divergent and benefit from increased CO 2 in seawater, since they increased their productivity and were tolerant of decreased pH. Thereby, these macroalgae can be relevant for CO 2 sequestration in mangrove ecosystems. However, the ocean warming and increased salinity in estuaries will be detrimental to the physiological performance of macroalgae from both climatic niches, even as they adjust their metabolism to synthesize compounds related to thermal and saline tolerance. Our data suggest that tropical macroalgal populations are more vulnerable to warming than subtropical populations, since tropical populations already live closer to their upper thermal tolerance limits. Our data also demonstrate that both species are euryhaline and can be characterized as typical “shade plants”. Thus, increased solar radiation on estuarine ecosystems due to global change will be harmful to both Bostrychia species. In our investigation, we documented for the first time the effects of ocean acidification on Bostrychia species, the first COI-5P sequences generated for both species, physiological strategies of Bostrychia spp. for thermal acclimation, a lethal temperature condition for Bostrychia species (34 ºC for the tropical specimens), a new organic osmolyte distribution pattern in Bostrychia species (only dulcitol in B. calliptera), and the deleterious effects of increased light stress on Bostrychia spp.

Bioregionalization is the effort to identify and map geographical boundaries for distinct biota at different spatial scales. Clear delineation of biogeographic units based on community data can provide a framework for testing hypotheses and for directing biodiversity conservation efforts. The aim of this Thesis is to identify and map tree biogeographic units in Latin America at different spatial scales, investigate the floristic relationships between the identified units and the main factors responsible for the formation of floristic units in geographic space. The Thesis is structured in three articles. We used a community-level modelling approach, and hierarchical and non-hierarchical classification techniques to map the biogeographic units at different spatial scales. In Article I, we compiled woody species occurrence data from 301 assemblages distributed over the geographical extent of the Amazon rainforest. Occurrence data were used to model the b-diversity along the entire extent of the Amazon and thus to map floristic units (subregions). We used multinomial logistic regression model and statistical deviance partitioning to investigate the influence of environmental, historical and human factors on the distribution of Amazonian subregions. We identified 13 woody subregions in the entire Amazon Forest. The hierarchical subregion classification showed a broad Andean-Cratonic east–west division. Variation in subregions was explained jointly by human factors and spatial structure followed by environmental factors and spatial structure combined. In article II, we propose two bioregionalization schemes for tree species of the Cerrado-Pantanal complex, based on occurrence and abundance data. We also evaluated the contribution of three sets of determinants of the occurrence- and abundance-based subregions. For modelling, we compiled data on tree species composition from 894 local assemblages based on species occurrences, and from 658 local assemblages based on species abundances. We identified 18 occurrence- and four abundance-based subregions in the Cerrado-Pantanal complex. Variation in subregions were explained mainly by environmental factors and spatial structure in both occurrence and abundance datasets. The occurrence and abundance-based subregions are complementary approaches to disentangle the macroecological patterns and to conservation planning in the Cerrado-Pantanal complex. In Article III, we present regionalizations of the tree flora of Latin America using two dimensions of b-diversity, taxonomic and phylogenetic. We assessed taxonomic and phylogenetic floristic relationships between groups at different spatial scales. We used species occurrence data from 7306 tree assemblages to model taxonomic and phylogenetic b-diversity across Latin America. We identified 128 taxonomic tree subregions and 101 phylogenetic subregions. The tree subregions were grouped into 54 mesoregions, 16 macroregions and 9 supraregions. Phylogenetic subregions were grouped into 46 mesoregions and 15 macroregions. Our proposed bioregionalization in Latin America revealed a detailing of tree biodiversity patterns not usually presented in continental-scale studies, revealing ecotone areas between known biome boundaries, as well as the evolutionary and geographic history between regions.

Although costly, group living is widely distributed in nature. Among birds, crows and ravens (Corvidae) stand out for their cognitive ability and for forming social groups that provide better performance in caring for offspring. Cyanocorax cyanopogon (White-naped Jay) are endemic to Brazil and occur mainly in Caatinga and Cerrado, two
biomes with strong seasonal component, alternating between periods of low and high productivity. In order to understand the strategies used by these birds to live in these biomes: 1) we will verify if they adjust their reproduction to the availability of resources in the environment; 2) we will analyze if the environmental characteristics and the availability of resources interfere with their occurrence in an area of Caatinga; and 3) we will describe the social structure of the groups of individuals that use the area of the FLONA-Açu. In our records of nests we found that the development of the nestlings lasts about 7 months, from the construction of the nest until they acquire adult plumage. Putting our reproductive records together with those available on Wikiaves and comparing them with the WorldClim precipitation data, we found that most of the records anticipate the month with the highest rainfall volume. We also found that this trend is stronger in the Cerrado than in the Caatinga. We compared 128 models generated from our global model with 8 environmental variables. Of the total, 5 models were the most representative. The most relevant parameters for occupancy were: season, distance from headquarters and NDVI (Normalized Difference Vegetation Index). In this model the occupancy estimate for the rainy period was almost half of what was observed in the dry period. Occupancy also varied positively as a function of NDVI and negatively as a function of distance from headquarters, both with greater effect in the rainy season. We captured and ringed 89 individuals at the headquarters of the Açu National Forest. However, between January and the end of July 2021, we revived only 42 of them. In these resightings were nestlings and some adults. The consistent resighting of a few individuals together is a strong indication that they maintain a family group formation within the study area. Our results from monitoring individuals in the headquarters area of the Açu National Forest showed that individuals form relatively consistent groups over time. We also verified that individuals ringed as nestlings, in 3 different years, remained together during this period. With the co-occurrence records we built a general network, from which we derived sub-networks, with records in the dry season and another with the rainy season records. The general and dry season networks showed similar density values (0.41 and 0.42, respectively) and modularity (0.43 and 0.40, respectively), but very different from that obtained for the rainy season (0.14 for density and 0.67 for modularity). These results indicate greater connectivity between individuals in the dry season than in the rainy season. This is associated with higher resource availability in the rainy season, which is also amplified by the reproductive period of the species.

Understand which factors caused species diversification is fundamental to know the history of life on Earth. The neotropics is one the richest regions and much remains to be known about the processes underlying diversification in this region. Central and South America formation was marked by dramatic geological and climatic changes. In this study, we tested the effects of geological and climatic changes on amphibian from Ranidae Family diversification in neotropics. In chapter 1, we tested if allopatric speciation due to geological changes, or ecological speciation due to new environments, played a main role in Lithobates palmipes group diversification. Using ancestral range estimative and phyloclimatic analysis, we found that L. palmipes group diversification is related to dispersal to new areas followed by climatic niche divergence, suggesting the prevalence of ecological speciation. In chapter 2, we tested the effects of the connections between the Atlantic and Amazon Forest on the diversification and ecology of the L. palmipes species through phylogeographic, phyloclimatic analyzes and niche modeling. L. palmipes comprises a species genetically structured by biome. Phylogenetic relationships, and niche modeling indicate the usage of northeast connection during the Pleistocene, which caused rapid niche divergence between groups in each biome. Despite the structure by biome, one of the mitochondrial lineages is composed by individuals from eastern Amazonia and the Atlantic Forest, while the other is composed by western Amazonia individuals. Based on our result, the diversification of the L. palmipes species group is the result of the interaction between geological and climatic changes in the Neotropics.

The manatee, Trichechus manatus, is classified as an Endangered species in Brazil, with an estimated population of 1100 individuals and threatened by habitat loss and fragmentation. This study aimed to investigate the suitability of the habitat available for the species along the Brazilian coast, as well as the degree of cumulative impact. For this, an ensemble forecast was created from 120 habitat suitability models built using the BIOCLIM, Domain, Mahalanobis, GLM, Maxent and SVM algorithms, based on important environmental variables for manatee distribution. The suitability results obtained were used to build T. manatus potential distribution map and compared to the degree of cumulative impact observed in the coast of Brazil. Areas of low suitability for the species were found in the mouth of the Amazon River, and in parts of the coast of Maranhão, and Rio Grande do Norte. The areas of high suitability are more consolidated between the east coast of Ceará and the coast of Alagoas states, with patches of high suitability also on the coast of Piauí and Maranhão states. The southern limit of potential distribution observed was the Todos-os-Santos Bay, in the state of Bahia. Cumulative impact analyzes indicate that most of the high suitability areas are under low impact. It was also observed that the areas of high suitability and high cumulative impact are concentrated in the Northeastern Brazilian coast, especially close to the state capitals. Continuous patches of high cumulative impact were also observed from the Parnaíba River Delta to the Piauí-Ceará border, and along the entire coast of the state of Pernambuco. The results found in this study can help in the development of conservation strategies for the species along the entire coast of Brazil, supporting decision-making and the allocation of resources more efficiently.  

Cetaceans are highly dependent on sound for vital activities and have been negatively affected by anthropogenic noise, which can cause from behavioral changes to physical damage. Mass strandings have been linked to active sonars, which seem to mainly affect deep diving species. Another noise source of concern are seismic surveys (SS), an activity that uses airguns to generate high-intensity impulsive sound waves. However, the causal effect of seismic surveys on the mortality and stranding of cetaceans is still controversial. We examined the relationship between cetacean strandings and 3D seismic surveys in the equatorial northeastern Brazil, accounting for the confounding effects of some oceanographic variables. We gathered the strandings registered between 2000 and 2019 in the states of Ceará and Rio Grande do Norte and separated the species into 5 ecological groups according to its occurrence, size, and usual diving pattern. Then, we characterized the spatiotemporal occurrence of the strandings and selected two areas where the search effort was more consistent. For these areas, we analyzed whether SS and wind and wave conditions affected the occurrence and number of strandings of each ecological group. We also simulated the drift of mimic cetaceans considering a constant mortality rate inside seismic operations´ limits and compared the spatial distribution of these simulated landings to the observed strandings for the same period. In the 20 years considered, 351 strandings were recorded, including 22 species and 5 families. Stranding records were higher in summer, when tourist seasonality increases the surveillance of beaches, and increased along the years, which may reflect an increase in monitoring effort in response to environmental constraints from 2010 onwards. Seismic surveys also increased in coverage area and duration compared to operations of the first decade of compiled data. From the 65 strandings that occurred up to one week after an SS operation, 5 had pathological alterations compatible with gas embolism syndrome, which might be associated with exposure to seismic exploration activity. SS occurrence increased the strandings of oceanic species with shallow dive, despite oceanographical factors. The number of strandings of deep diving species as well as all species combined was also affected by SS occurrence, when considering specific wave states. Furthermore, 36% of the observed strandings positions overlapped with landings from simulated mortality inside seismic operational areas. Drift simulations showed that animals that could have died in SS of Ceará may beach in other states of Brazil and would go undetected by the current beach monitoring efforts. Areas with highest landing probabilities for animals that died within seismic operation areas may reach north well beyond the extension of beach monitoring programs required by the environmental regulation institution. We recommend that previous drift simulations are carried out as a requirement of the licensing process to determine which portion(s) of the coast should be monitored in beach monitoring projects. Results revealed that a portion of the animals reported were affected by seismic surveys while another large portion of affected animals would not be detected because of drift effects. Thus, the impact seen here is likely an underestimate of the actual impact of seismic surveys on the mortality and strandings of cetaceans in the region.

Lenticels are pore-like structures, commonly originated in the substomatic cavity through a more intense meristematic activity of the phelogen. Unlike cork cells, which are tightly arranged and have suberified walls, lenticels are made up of cells with a rounded shape and delicate walls, a characteristic that allows for the presence of large intercellular spaces, which are directly related to the known functions of these structures. Lenticels are present in a variety of organs and species of terrestrial plants, presenting distinct adaptations that help individuals to establish themselves in the face of changes in the environmental conditions experienced. Although lenticels were described two centuries ago, there are many gaps in knowledge involving these structures. This dissertation  to clarify the importance of lenticels and understand how these structures occur in plant species from semiarid environments. The first chapter aims to carry out a literature review on lenticels in order to understand how different approaches and studies have been developed over time, also seeking to map specific fields of knowledge that still need to be filled. Specifically, we sought to: 1) Describe how lenticels occur in different phylogenetic groups of plants; 2) Describe in which plant structures the lenticels can be found; and 3) Describe the main functions that are given to lenticels. For this, we reviewed the specific literature through searches in scientific repositories, readings and cross-references. We found that lenticels are not exclusive to stems and roots, occurring in several organs, being present in species of “pteridophytes” (monilophytes), gymnosperms and angiosperms. In addition to gas exchange, lenticels perform other functions, such as water absorption, also serving as transpiration points. These structures can respond to environmental stressors, showing adaptations to the environment. Although knowledge about lenticels has grown over the years, there are still gaps to be filled, especially in arid and semi-arid climates, since most studies published to date deal with plant species from wet and humid environments. In the second chapter, we aim to describe the morphology of the lenticels and stem of 14 woody species from the Caatinga, in order to search for possible morphological patterns and separate them into functional types. Individual samples were collected for each species and histological slides were prepared for anatomical description. Additionally, lenticels were analyzed using electron scanning microscopy and fresh material under stereomicroscope for descriptions of external morphology. We found a difference between the morphological characteristics of the lenticels, as well as the general morphology of the stem. We also observed two patterns of structural changes and construction of occlusion layers in the lenticels, which indicates at least two possible strategies adopted by species adapted to semi-arid conditions, suggesting that the lenticels of plant species can evolve distinct characteristics in response to drought. The presence of occlusion layers can favor species in seasonally dry tropical forests, reducing transpiration rates and also allowing gas exchange in the absence of leaves in deciduous and semi-deciduous species in the dry seasons.

Understanding factors related to birds’ life-history traits variation is essential to answer ecological and evolutionary questions. Studies about variations in life histories examine mainly the effects of limited food, predation, and climatic conditions. As a result of trade-offs, variations in life histories follow a ‘slow-fast tendency’ which ranges from high fertility and low survival to low fertility and high survival. Thus, tropical species tend to invest more in self-maintenance than in current reproduction, while species from temperate zones do the opposite. Tropical environments are considered to be less seasonal and have high food resource stability. However, this information is based essentially on humid tropical environments. Pondering these knowledge gaps about Neotropical environments, we aimed to verify the applicability of these pre-established standards regarding the Neotropical birds’ life history. We gathered a field database from 15 sample areas plus 11 more areas from literature data. In this thesis, we used survival estimates from 327 populations, of which 147 were unpublished estimates and 180 estimates from the literature. Field collections took place at different times between 1999 and 2019. The sampling time in each area ranged from 2 to 20 years. The sampling areas covered latitude variation from 20º N to 34º S. We used survival estimates of environments with different intensities of climatic seasonality to test the hypothesis of a relationship between climatic seasonality and survival. The survival values found were similar throughout South America, indicating that other factors may act more intensely on the survival variations of these birds. Our results suggest that the seasonality conditions in South America are not intense enough to reflect on the species survival. Behavioral and physiological changes may mitigate the extrinsic mortality of adults. Furthermore, the young high mortality rates suggest that birds from seasonal tropical environments also favor residual reproductive investment through strategies that guarantee greater survival expectancy for individuals.

Shorebirds are considered one of the most impressive groups of birds due to their long migratory movements between breeding and wintering sites located in wetlands, and sometimes located in different hemispheres. This complex movement associated with the great diversity of habitats used by species during migration also implies threats at different scales, and a challenge for conservationist policies that prioritize the protection of wetlands. Despite international efforts and the creation of a national instrument for the conservation of the group, few protection areas have been implemented. To assess information on patterns of richness, distribution, movements and how species will respond to climate change in the future, we have developed the present thesis in two chapters. In chapter 1, we assessed patterns of distribution, movement, and richness of 28 migratory and resident shorebirds species along Brazilian wetlands, using the kernel density method and generalized additive models. Our results revealed two distribution patterns assessed by the projections of the kernel estimates: some species occurred more widely distributed, mainly along coastal and inland areas, and another species with more restricted records, mainly along the coastline. These data also show movement patterns that varied for species, with some migrating only along the Atlantic flyways, others using both flyways (Atlantic and Central flyways), and some species using both. For the models, the best candidate model explained 97% of the data and it was influenced by the agricultural, forest remnants, urbanism, beaches and dunes and non-forested natural areas, the first two negatively affecting the shorebirds richness and the last three positively. In chapter 2, we used spatial predictors of climate, energy, and habitat heterogeneity to test which hypothesis best explains the patterns of shorebird richness in Brazil. We identified a negative relationship between species richness and the variation between maximum and minimum temperatures, indicating that more climatically stable environments are associated with higher levels of richness in the shorebirds group. In Chapter 3, we combined occurrence records with climate, topography and land cover data, to model the habitats availability of resident and migratory shorebirds in Brazil, and to identify how their habitats will be affected in future forecasts of different scenarios of carbon concentration (RCP 4.5 and RCP 8.5). Our results showed that both RCP’s scenarios indicated a balance of losses greater than that of gains, with most predicted species losing more than 50% of their projected habitats for 2050 and 2070. Still, using binary maps produced through estimates for each species, our projections revealed important areas located along the southeast, north and south coast of the country, regions in the Pantanal and along the Amazon River, which are also expected to suffer severe habitats losses in the future. In chapter 3, we will combine occurrence, climate, and marine variables to discuss the predictors preferred by species when choosing their sites along the coast, and how richness varies across these environmental gradients. Our study integrates additional information on distribution, movements, and shorebirds richness, in addition to future perspectives on the consequence of global warming in the habitats used by shorebirds in Brazil. These results raise the urgent need to implement measures to control impacts on semi-anthropized habitats, protection and better management of wetlands and implementation of sustainable policies.

Seaweeds play several roles for associated fauna (shelter from predation and/or stressful abiotic conditions, substrate, food and sediment retention). In this context, this work was divided into three chapters to investigate how the structural complexity of different seaweeds may affect ecological aspects of the associated fauna (richness, density, diversity and composition) and which role seaweed complexity and chemical composition play on habitat and food choice by their fauna as well as predation. In the first chapter, the influence of seaweed structural complexity was analyzed based on ecological aspects of the fauna associated with six species of seaweeds. The ecological aspects were evaluated considering the fractal area (spaces between branches), the fractal perimeter (contour level) and the volume of seaweeds. Halimeda opuntia had the highest values of richness and diversity. Dictyopteris delicatula harbored the highest density. Regarding faunal composition, H. opuntia and Gelidium coarctatum had the most distinct communities. In the second chapter, experiments were carried out to assess the choices (food, habitat and chemical cues) by amphipods concerning different species of seaweeds. Gracilaria cervicornis was the most consumed seaweed among the species offered. Moreover, in the experiments of chemical cues (mimics with and without algal extracts), the amphipods were attracted only by those with extracts of G. cervicornis. These results indicate that amphipods are likely attracted by chemical cues from G. cervicornis as they serve primarily as a food source. In the third chapter, experiments were carried out to determine whether the seaweed choice by amphipods is influenced by predators based on chemical cues. The amphipods preferred D. delicatula cues over G. cervicornis and G. coactatum cues, but switched their choice to G. cervicornis when predator cues were added to D. delicatula cues and remained in G. cervicornis even when predator cues were added compared to G. coarctatum cues. These results demonstrate that, although they prefer some seaweeds, amphipods are able to adapt their behavior based on predator chemical cues.

Local Ecological Knowledge (LEK) is increasingly important within science to discuss the conservation of biological resources and ecosystem processes. Here in this thesis, we describe how LEK contributions and potential for building hypotheses in ethnobotanical use, phylogenetic structuring within the optimization of use and for the rescue of biocultural memory; and the insight to assess ecosystem services. The initial objective of the thesis is the Local Ecological Knowledge of the relationship between farmers and wood and medicine plants, filling a gap in ethnobotanical work in the Agreste Potiguar region. Within this first main objective, we have specific questions: 1) What are the social characteristics associated with the most specialized informants in the use of wood from the analysis of phylogeny? 2) How is the pattern of species dispersion along the phylogeny created from the knowledge of farmers for various diseases distributed over 11 parts of the human body system and 10 morphological structures of the plants mentioned? The second main objective is to know two parts, in the way of life of the communities they perceive the Local Ecological Knowledge. For the specific purpose of this second part, we will classify as consensus analyses for four classifications associated with ecosystem services. The results show that there are patterns of dispersion within the ecophylogeny of the species built from the citation of family farmers in the rural region of the state for wood and medicinal uses. Within medicinal uses, plant morphological structures tend to form a more phylogenetic pattern than human body systems. Regarding the perception of ecosystem services, both agricultural and environmental actors have different perceptions about the immaterial mechanisms associated with conservation and Local Ecological Knowledge. We ask the actors, researchers associated with conservation and the rural world to respect and guarantee all the rights included so that the Indigenous Community of Catu, perhaps the only one within this rural territory, can reproduce its activities and ways of life, because it is around this territory that farmers cite more species associated with biocultural memory.

Due to their proximity to more populated areas, coastal reefs may be potentially more prone to the effects of anthropogenic impacts compared to oceanic reefs. In these environments, corals can respond more quickly to these impacts, with changes in their health status, depending on the species and environmental variables such as depth, temperature and exposure to light. Comparing the health of corals in coastal and oceanic environments, within the same latitudinal range, can provide information on how anthropogenic impacts and the natural dynamics of the environment affect these ecosystems. We monitor colonies of the Siderastrea stellata (~ 5m deep) and Montastraea cavernosa (~ 30m deep) corals on coastal (Rio Grande do Norte; ~ 5 ° S) and oceanic (Fernando de Noronha; ~ 3 ° S) reefs in northeastern Brazil. In these places, the species monitored are among the main coral reef builders. We monitor quarterly for one year (2018-2019), using three-dimensional models generated by photogametry. From the generated models, we evaluated coral health indicators (bleaching, mortality, diseases and algal overgrowth). Both monitored species showed good health in coastal and oceanic reefs throughout the year, with no record of intense bleaching during the monitored period. In one of the oceanic reef environments, we observed periods and greater bleaching related to the natural dynamics of this environment leading to the burial of the colonies. Colonies of S. stellata remained in general healthier in coastal areas than in the oceanics, which may be related to less exposure to light in coastal areas compared to ocean reefs due to greater water turbidity. The health status of M. cavernosa was stable and, despite having differences between coastal and oceanic areas, the corals in all monitored sites had, on average, 80% of their surface in a healthy state. The surface water temperature was also similar and relatively constant in coastal and oceanic reefs. Coral health was more affected by variations in the local ecosystem (e.g. natural burial) than by proximity to human impact, indicating that local temporal dynamics need to be considering when assessing the response of corals to human impacts.

Evolution of plant mating system, such as selfing and outcrossing ways, is an intriguing question in plant biology, since that can suffer influence of several ecological factors. The Red Queen hypothesis suggests that biotic interactions parasite-host-like is the major factor driving the evolution and persistence of sexual reproduction in nature. Therefore, in light of this hypothesis, is expected that species under high pressures of natural enemies, present high investment in sex, that in plants it can be measurement by the outcrossing rate, a metric based in molecular markers. There are support for Red Queen for several groups of animals, however in plant kingdom this hypothesis remains underexploited, especially using comparative approaches. Here, our main objective was test if the evolutionary pressure of insect herbivores is effective in predict outcrossing rates in seed plants. For that, we fitted phylogenetic regressions using two independent datasets for these two variables, also including some vegetative covariables: life span, growth form, specific leaf area and maximum height. The regressions were performed under two alternative evolutionary models: Brownian Motion and Ornstein-Uhlenbeck. We also tested the Red Queen prediction for natives and exotics species, to analyze the role of the coevolutionary time between plant and herbivores in mating system driving. We found, in both models, that plant species under higher pressure of insect herbivores richness had higher outcrossing rates. The same pattern remains in native species but not in exotics. In the same line, we found that tall and longer-lived plants tend to be higher outcrossing rates than small and short-lived. These results are in accordance with the expected by the Red Queen hypothesis, supporting the still scarce empirical framework of macroevolutionary studies about the role of natural enemies on evolution of mating system in seed plants.

Tropical ecosystems harbor higher biodiversity, more intense and diverse ecological interactions than extratropical ecosystems. These latitudinal patterns result from long-term evolutionary processes, but the fast expansion of tropical species polewards due to climate change is altering biodiversity and interaction patterns. Tropicalization events have been identified for many marine organisms, including reef fishes, but the effects of climate change on large-scale patterns of species interactions are still poorly understood. Reef fishes area a good model to investigate these changes because they are critical consumers in reef ecosystems throughout latitudes, whose large-scale patterns of diversity and interactions are well understood. Because temperature affect the physiology of organisms, particularly ecthoterms, we hypothesized that (i) future warming of extratropical zones may intensify trophic interactions and enable tropical species to establish new interactions in these areas; and that (ii) increasing temperatures predicted for the near future would intensify trophic interactions in the tropics, up to the physiological limits when interactions would be no longer viable. This is the first study to evaluate how trophic interactions of different trophic groups (herbivores, invertivores and omnivores) will respond to increasing temperature scenarios. We used data on reef fish occurrence, biomass and patterns of fish trophic interaction on the benthos across 61° of latitude in the Western Atlantic, and applied Bayesian models to predict the intensity of interactions in 2050 and 2100 based on the Intergovernmental Panel on Climate Change (IPCC) scenarios. Trophic interactions will decline between 50-100% in the tropics, likely indicating that increased temperatures will exceed the physiological thermal tolerance of fishes. In the Northern hemisphere, from 20°N to 40°N, interactions will increase about 100%, likely due to tropicalization of herbivorous fishes and marine currents northward. This phenomenon was not observed in the Southern hemisphere. Interactions by invertivores will decline between 5-100% along Western Atlantic, indicating they may have a narrower thermal tolerance. Interactions by omnivores will decline about 100% at northern and about 30% at southern extratropics, but are likely to increase about 5-20% in the tropics, which could result from their feeding plasticity adaptations to different temperatures. Alternatively, fish can adapt and acclimate to changes in environmental conditions, but if there will be enough time for that to happen is still unclear. Predicting how climate change will affect trophic interactions may help understanding the future of ecosystems and the services they provide.

In the Brazilian semiarid, the Caatinga is susceptible by several chronic disorders that threaten the living conditions of the human population. Ecological restoration is important to achieve biodiversity recovery and ensure the provision of ecosystem services (ES) relevant to the well-being of local communities. However, there is a lack of studies that focus on the mismatches between the ES supply and demand. In this sense, we seek to identify priority areas that address the ES supply and demand. To aim this goal, we use two ES provision (wood and food and / or medicinal use) and an ES regulation (pollination). We developed two scenarios for each service: (i) ES offer which we used the maps of the potential geographic distribution of native tree species and (ii) ES demand, which we included, areas ES supply and demand. We conducted the prioritization in Software Zonation, a responsible spatial tool for prioritizing areas that have the highest potential to increase biodiversity and provide ES. We found a percentage increase in representation in demand scenarios in all SEs, following in increasing order, the provision of food and / or medicinal species (1.5%), provision of wood (1.8%) and the most significant pollination (69.1%). These results indicated that for some ES the supply corresponds to the demand while for others there is a mismatch between them. This ES – provision of food/medicine and wood supply - showed larger overlap between supply and demand, signaling that active restoration actions in these areas can directly contribute to improving the welfare of people dependent on the extraction of forest resources.

Cacti species play a major role in frugivory networks in arid and semiarid ecosystems. In such environments, where water and food resources are in short supply most part of the year, cacti stand out for their fruit rich in water and sugar, and its mucilaginous pulp. Several studies reinforced the role of birds, bats, and lizards as effective cacti seed dispersers, although little is known about how these interactions are distributed in a network. Network structure provides information about the system stability in the face of disturbances and how tight or weak are interactions between species. Our objective was to describe network structure of mutualistic network of cacti-seed dispersal by vertebrates in SDTF (Caatinga), Rio Grande do Norte State, Brazil. We also identified the main cacti fruits consumers and their ecological role as seed dispersers. For that, we monitored frugivory in six cacti species using camera-traps during a year. We found 23 vertebrate species feeding on fruits of four cacti species, in a way that these interactions were not nested or modular, which is a common pattern found in mutualistic networks in tropical and temperate regions. Our data show that cacti have a generalist strategy of attracting a wide variety of animals that provide different dispersal services, such as birds, reptiles, and mammals. During our study, we found new interactions between lizards Salvator merianae to P. gounellei fruits and Tropidurus hispidus feeding on T. inamoena flowers. These records were described in a second chapter. For natural regeneration, it is crucial to maintain ecological services provided by functionally diverse of animal seed dispersers and this should be taken in account in conservation actions that aim to restore Caatinga areas dominated by cacti species.

Vegetal detritus decomposition is a key process in nutrient cycling and can be affected by both biotic and abiotic factors. Although many studies have evaluated the effects of litter diversity on its decomposition rate, most works use experimental and short-term approaches. Our aim were, using an observational approach based on estimates of the mass balance between the input and the debris stock during 3 years. For that, we assess, in 41 plots in a restinga forest fragment, the litterfall, soil litter, taxonomic, functional and phylogenetic litter diversity, C:P and C:K ratios and water-holding capacity of litter, in addition to the soil moisture and N, P and K concentrations. After building 54 models of path analysis, our significant models showed that soil moisture was the only variable to affect the decomposition rate of litter in our communities. The results suggest that the decomposition of the litter is not driven by any of the possible effects of diversity: neither by mechanisms of selection nor of complementarity. In fact, at our study site, the results indicate that the decomposition of plant debris is affected by physical attributes of the environment, i.e. soil moisture, probably because it affects the activity of the decomposing microorganisms.

Reefs are sensitive ecosystems affected by global changes (e.g., warming and acidification of the oceans) and local impacts (e.g., fishing and eutrophication). Recent records show that these ecosystems are changing rapidly, although the magnitude and timing of these changes are still unclear. We assessed changes in the seascape of Brazilian reefs, interviewing key stakeholders that make different uses of these ecosystems, such as fishermen, divers, and researchers. For most stakeholders, the health of Brazilian reef environments has been declining since the 1970s, evidenced by the decline of herbivorous fish within the Labridae: Scarinae (parrotfish) group and reef builders (massive corals). On the other hand, these authors also detected an increase in algae and smaller fish of the family Pomacentridae (damselfishes), in addition to pointing out the recovery of sea turtle populations. Assessing the memory of reef users allows determining the timing of these changes, to identify regional idiosyncrasies and groups of organisms that are most vulnerable to changes. This information is important to inform protection and conservation efforts, especially in developing countries, where marine research is relatively new or insufficient.

Providing fish and seafood from fishery catches is one of the most important ecosystem services that humans derive from the ocean, and as such, commercial fisheries regulation should be a priority. In order for the assessment of multi-specific fisheries to be broader and more sensitive to change, it is advisable to investigate various types of indicators, portraying the broadest possible scenario. Using reconstruct landing data and data provided by fishermen, this project proposes, through the Marine Trophic Index, Species Distribution Models and socioeconomic indicators to evaluate changes in fishing in the Brazilian equatorial region and how these changes impact fishermen, using communities from Rio Grande do Norte and Ceará as case studies. The results are expected to help better understand the changes and dynamics of fisheries and fish stocks in this region, helping to subsidize fisheries management decisions

Nutrient cycling is a fundamental ecosystem service as it provides an adequate balance of elements that are necessary for life. In freshwaters, the balance of nitrogen (N) and phosphorus (P) are of special interest as they often limit or control primary production and biomass formation. While the availability of these nutrients is fundamental for the maintenance of biodiversity and productivity of freshwaters, their excess can lead to eutrophic conditions that are associated with impaired water quality and biodiversity loss. The nutrient balance in freshwaters can potentially be affected by a variety of biotic and abiotic, external and internal pathways. In this thesis, two frameworks were explored. First, a spatial framework focused on external processes, where we investigated the direct and indirect effects that land use (i.e. type, extent), precipitation and landscape properties (i.e. lake origin, lake and catchment absolute and relative size and geomorphology) have on biotic and abiotic properties of freshwater systems. More specifically, in chapter one we evaluated, across 98 tropical lakes and reservoirs, the individual and interactive effects of land use, precipitation and landscape properties on patterns of water quality parameters (N, P and chlorophyll-a). In chapter two, we characterized the 98 lakes as natural or artificial and compared them regarding the landscape properties of their surroundings, their morphometry, and their physico/chemical characteristics to verify whether those factors can be associated with average patterns of phytoplankton community structure at both local and regional scales. The second approach, presented in Chapter 3, was a long-term temporal framework focused on internal processes related to nutrient cycling where we assessed whether an omnivorous fish with high biomass and growth rate is a source or sink of N and P to the pelagic zone of a temperate eutrophic lake, at various time scales ranging from days to 20 years. 

Seasonal Dry Tropical Forests (SDTF), such as the Caatinga, are considered adverse environments due to their high temperature, scarce and variable rainfall and seasonal restrictions on the availability of water and food resources. These characteristics can affect the assemblies of mammals and plants and, therefore, their life histories. Several mechanisms of persistence in neotropical SDTFs have been described for bats (migration, dietary plasticity, morphological differences, foraging strategies) and for plants (deciduity, spines, seasonal phenology), all influenced by precipitation and temperature. In this doctorate we delve into the lives of four species of nectar-feeding bats: Glossophaga soricina (Phyllostomidae: Glossophaginae), Lonchophylla inexpectata, Lonchophylla mordax and Xeronycteris vieirai (Phyllostomidae: Lonchophyllinae). We describe their interaction networks with plants (Chapter 1), explore their mechanisms of persistence and coexistence over time (Chapter 2) and, finally, tested the influence of precipitation and the availability of Cactaceae resources on the reproduction patterns of the nectar-feeding bats (Chapter 3). The field work was carried out in seven locations in the state of Rio Grande do Norte, between May 2015 and February 2019. Using mist nets to capture the bats, we noted the capture hour, species, reproductive status, sex and eco-morphological measures. To characterize the species' diet, we collected bat hair pollen samples (glycerin gelatin cubes) and fecal samples. To determine the availability of resources, we collected phenological flowering data of nine plant species.

The studied nectarivorous bats interacted with 31 plant species forming a network with a highly generalized pattern of interactions, consistent over the seasons and years. The observed generalization may be a necessary condition for the persistence of nectarivorous bats and their specialized plants in variable and challenging environments such as the Caatinga. In chapter two, we were able to prove that the four species of nectarivores coexist and persist over time (years and seasons) mediated by a mixture of mechanisms (temporal partitioning, eco-morphological differences and resource partitioning). Finally in chapter three, we found that precipitation positively affected the probability of ocurrence of pregnancy in L. mordax and X. vieirai. None of the tested variables (precipitation nor Cactaceae resources availability) influence the pregnancy of G. soricina. On the other hand, the availability of floral resources of Cactaceae from the previous month, positively affected the probability of occurrence of lactation for all nectarivorous bats. With this research, we were able to emphasize the importance of interactions between cacti and bats. The Cactaceae family is a key resource for the persistence, coexistence and reproduction of nectarivorous bats in the Caatinga, therefore conservation initiatives should consider areas with high abundance and diversity of Cactaceae as a priority.

Dry tropical forests are threatened and little-known ecosystems where the association between the semiarid climate and the generally high environmental degradation imposes challenges for the persistence of wild fauna. In this context, medium to large-sized mammals (MLSM) are especially affected by anthropogenic disturbances, among which, carnivores are intensely persecuted, impairing their role in structuring biological communities through predation and intraguild competition. In this thesis, we investigated the occurrence and coexistence patterns of MLSM in different landscapes of the Caatinga, the Brazilian dry tropical forest, using camera trapping data. Specifically, we 1) carried out the first systematic survey of MLSM in the Rio Grande do Norte state (RN), sampling 10 priority areas for conservation; 2) we described the daily and seasonal activity patterns and estimated the temporal overlap among mesocarnivores using circular statistics and non-parametric analyzes of activity overlap; 3) we investigated the patterns of spatial co-occurrence between a dominant mesopredator (Leopardus pardalis) and sympatric mesocarnivores, considering seasonality and using conditional co-occurrence models; and finally, 4) we tested the relative effects of environmental and anthropogenic predictors on MLSM’s occupancy in a landscape disturbed by high cattle density and during a period of extreme drought, using Bayesian occupancy models in a multi-species approach. As main results, we found 1) a wealth of 14 MLSM’s species in the Caatinga of RN, which represents 50% of the MLSM registered at north of the São Francisco River, including threatened species as a top predator (Puma concolor). 2) Mesocarnivores were mainly nocturnal throughout the dry and rainy seasons, overlapping most of their daily activity, but segregating the peaks of greater activity, which may represent a coexistence mechanism. Meanwhile, Herpailurus yagouaroundi was diurnal, avoiding encounters with competitors and synchronizing its activity with potential prey. 3) Spatially, the other mesocarnivores used the habitat regardless L. pardalis’ presence, with the exception again of H. yagouaroundi, which seems to prefer the same locations as this dominant mesopredator, probably because they have better conditions and resources, while temporal segregation decreases risk of aggressive encounters. 4) MLSM occurred mainly in patches of forest vegetation, which represent a key habitat for the persistence of this group in a degraded landscape under prolonged drought, and where many species showed an extremely low abundance. Therefore, these environments must be protected to guarantee MLSM’s persistence in Caatinga. Our results reinforce the relevance of priority areas and habitats for mammals’ conservation in the Brazilian dry tropical forest, in addition to elucidating the intraguild coexistence strategies that maintain the mesocarnivores diversity in this semiarid environment.

Overhunting is one of the greatest threats to wildlife worldwide and has caused a sharp decline in the abundance of large-bodied vertebrate populations in tropical forests. The implications are far-reaching since the most intensely hunted species are often involved in key ecological processes related to forest dynamics, including seed dispersal and predation. Defaunation disrupts these plant-animal interactions, which are essential for forest regeneration, and can compromise the maintenance of plant diversity and ecosystem services. This thesis explores the cascading effects of defaunation on vertebrate and plant communities using a hunting pressure gradient in the Médio Juruá region of western Brazilian Amazonia. In the first chapter, we analysed the direct and indirect effects of hunting on mammal and bird communities. For this, we estimated vertebrate biomass using camera trapping in both the understory and forest canopy at 30 sites distributed along the hunting gradient. Overhunted forests showed changes in the size structure of the animal community with a decline in the biomass of hunting-sensitive species and an increase in the abundance of nocturnal rodents, possibly related to a density compensation mechanism. The second chapter explores the cascading effects of defaunation on future forest composition and functionality. We compared functional traits of trees and saplings, inventoried in 30 plots of 0.25 ha (=7.5 ha) established along the hunting gradient, to test for an expected decrease in traits associated to seed dispersal by large vertebrates. Our results indicated a modest decrease in the abundance of large vertebrate dispersed saplings compared to conspecific trees, and an increase in the prevalence of saplings from abiotically dispersed species. However, this effect did not reflect the community-wide pattern for the continuous traits of wood density, leaf mass/area (LMA) and seed mas. In the third chapter, we used dendrometric data from our forest inventory and comprehensive wood density sampling to estimate current and future carbon stocks, and thereby assess the potential impact on carbon stocks in intensively hunted forests. Of the 30 plots sampled, 22 could lose forest carbon in the future and the mean projected loss was 2.2 MgC ha-¹. For two protected areas (PAs) in the study landscape, the projected loss was approximately 1,560 MgC. Considering the currently predicted monetary values in the international carbon market, the projected decrease in the PAs future carbon stock was valued at US$15,600 to US$120,000.

Lakes and reservoirs are essential components for human development and carry out important ecosystem processes. Understanding the mechanisms that determine these processes is necessary in a scenario of climate change and consequent increase in the interdependence between society and natural resources. In lentic ecosystems, the production and transfer of matter and energy are largely carried out by the phyto-zooplankton communities. Diversity effects on ecosystem functioning of (BFE), driven by niche partitioning and selection effects in the community can affect these processes positively or negatively. However, it is necessary to elucidate which components of diversity are most important and what is the shape of the relationship between each function and its predictors, in addition to studies that observe these effects in natural environments. Testing the effects of biodiversity in conjunction with abiotic variables over a wide spatial range provides the necessary support to advance knowledge about BFE to predictive and applied models. The aim of this work was to analyze the relationship between different aspects of phytoplankton and zooplankton diversity on the functioning of aquatic ecosystems in 98 lagoons and reservoirs in the state of Rio Grande do Norte, Brazil. To measure functional diversity, metrics were calculated based on the distance of the functional traits of the communities, generating a functional trait space from which the richness, equitability and functional divergence were analyzed. In the first chapter, the effects of the taxonomic and functional diversity of phyto and zooplankton and the intraspecific functional diversity of phytoplankton over biomass and resource use efficiency of nitrogen and phosphorus were assessed. In the second chapter, the relationship between biomass and resource use efficiency of zooplankton and its relationship with the taxonomic and functional diversity of zooplankton and phytoplankton were analyzed. The effects of diversity were analyzed in regressions in Random Forest models, with selection of variables for the measure of importance, analyzing the partial dependence and the magnitude of the effect (ME) between the diversity and the focal ecosystem function. Significant diversity effects of high magnitude of zooplankton functional divergence for zooplankton biomass (ME = 1.09) and negative effects of taxonomic (ME = -0.4) and functional phytoplankton (ME = -0.77) on the rate of resource use of zooplankton. Phytoplankton functional divergence had a strong positive effect (ME = 0.82) on phytoplankton biomass, as well as phytoplankton functional richness (ME = 0.43) and negative effects of phytoplankton functional equitability (ME = -0.56 ). The nitrogen use efficiency of the phytoplankton community was positively affected by its functional divergence (ME = 0.65). The efficiency of phosphorus use has not been shown to be affected by diversity or environmental variables. The inclusion of intraspecific functional richness did not present good predictive abilities for phytoplankton. Dominance effects on ecosystem functions were observed, indicating selection effects of super-dominant cyanobacteria species and strong effects of functional divergence pointing to niche differentiation in highly productive communities at both trophic levels. Non-linear, positive and negative, effects, were observed between diversity and the functioning of ecosystems on a large spatial scale. Observing these effects in real ecosystems in conjunction with environmental variables confirms predictions made in experimental studies and expands the application of BFE in freshwater environments.

Natural communities are structured by physical and biological factors that drives local dynamics of species coexistence. On reef habitats, conditions such as current dynamics, waves, temperature, depth and nutrient availability plays an important role on structuring communities. Nutrient availability is a frequent limitation on marine environments. The island mass effect, for instance, when the allochthonous nutrient supply supports a diverse ecosystem, and the transformation of dissolved organic carbon into particulate matter by sponges (sponge-loop) have an important role on maintaining ecosystems on oligotrophic conditions. Most Brazilian reefs are rocky or sandstone formations with a great influence of continental run-off, being mostly dominated by macroalgae and presenting low coral cover. Biogenic reefs in Brazil occur in the Abrolhos bank and southern Bahia state, presenting high coral cover. Recently, biogenic reefs with high coral cover were geologically described on northern Brazilian coast. We described benthic and fish communities in these reefs using photoquadrats of benthic substrates and visual census of fish community. Three reef areas were chosen around an incised valley on marine floor, a potential pathway for nutrient input to the reefs, exploring variations among reefs at east, west and at the center of the valley. We found higher coral cover and lower macroalgae cover on reefs located within the incised valley. Fish biomass was similar among areas, but biomass distribution differed among functional groups. Invertivores and piscivores biomass was greater on reefs within the valley, potentially resulting from higher food availability resulting from increasing nutrient input. Our results reveal that nutrient inputs from incised valleys may structure reef communities similarly to what happen with the island mass effect. This work contributes to description of biological communities composing these recently described biogenic reefs, elucidates the potential effects of the incised valley on these reefs, and fills a gap on the knowledge on these kind of reef formation in Brazil, generating information that can be further used for guiding management and conservation of those unique ecosystems.

Intertidal mangrove forests play important roles for especies persistence, providing food and shelter from predators for marine and estuarine small fishes. Despite the great progress in knowledge of estuarine and mangrove systems in the last decades, little is know about fish community dynamics in the temporary enviroments of mangroves. The present study aims for understand how fish species are distributed inside the mangrove forest in temporary ponds along the estuary (spatial dynamics), between seasonal surveys (temporal dynamics) and according to microhabitat characteristics. Field work was conducted from november 2017 to september 2018 on the Ceará-Mirim river mangrove (Northeastern Brazil). We stabilished 17 10m x 10m quadrats distributed along the estuary, which were used as sample units. Our fish collection followed a standardized protocol. Limnologic and microhabitat variables (density of roots, ponds, crab burrows, propagules, canopy cover and pond number and depth) were mesured. 1189 individuals belonging to 10 species were collected. with Kryptolebias hermaphroditus being the dominant species (52% of total fish abundance), followed by Poecilia vivipara (24%), Ctenogobius smaragdus (11%), Ctenogobius shufeldti (2%), Ctenogobius boleosoma (2%), Evorthodus lyricus (3%), Dormitator maculatus (<1%), Eleotris pisonis (1%), Guavina guavina (4%) and Erotelis smaragdus (<1%). Abundance, richness and diversity increased in the rainy months. P. vivipara and Gobiidae species followed this pattern, with major abundances in this period. K hermaphroditus and Eleotridae species were more constant. We found a inverse relationship between diversity and abundance along the estuary, with major diversity and minor abundance occurring closer to de ocean, in constrast with upper areas with minor diversity and major abundance. P vivipara occured more in the upper areas of the estuary, while C. boleosoma and E. pisonis tended to occur more in areas close to ocean. Other species were more constant. The different microhabitat characteristics within the mangrove forest were also important in species distribution. We found evidences that the fish assemblages in the mangrove forest are modulated by rainfall cycle, the closeness to the ocean and to microhabitat characteristics and discuss these findings in light of the current knowledge on mangrove fish.

The Dark-billed Cuckoo (Coccyzus melacoryphus) is a species of 136 species of the Cuculidae family, which occurs throughout Brazil. In part of its distribution performs periodic movements, as in the Caatinga. In Rio Grande do Norte, its period of permanence is related to rainy season, occurring between the months of February and June when they arrive to reproduce. Studies on the reproductive dynamics of birds in seasonal environments have been focused in temperate regions, generating a knowledge gap for neotropical regions. This research tries to understand more about the reproductive dynamics of birds from seasonal environments, describing aspects of The Dark-billed Cuckoo’s breeding biology: reproductive period, nest and egg description, posture size, incubation and nesting period. We monitored nests at intervals of 2-3 days in the Estação Ecológica do Seridó – ESEC-Seridó, during the rainy season of 2017 and 2018. We recorded 63 nests of The Dark-billed Cuckoo, 31 between March 1 and May 8, 2017 and 32 nests between February 8 and June 10, 2018. The nests were built on shrubs and trees at a mean height of 1.61 ± 0, 88 m, and the pereiro tree (Aspidosperma pyrifolium) was the main plant used as support. The nests showed a “simple/platafform” format, with sticks showing a tendency to present the outer ones larger in length and diameter than the inner ones. The eggs were short subelliptical with light green coloration (color 81 Pearl Gray by Smithe 1975). The eggs mean weight was 9.7 ± 0.9 g, the length was 28.4 ± 1.5 mm and width was 22.1 ± 1.5 mm. The mean number of nestlings per nest was 2.60 ± 0.96 (n = 32). In its breeding biology, we believe that The Dark-billed Cuckoo acts like the other members of the genus, presenting a long reproductive period when compared to birds of temperate regions, with a probable short period of incubation and of the nestlings’ permanence.

Studies over the last two decades have pointed to an important role of the litter diversity, especially the functional one, as a determinant of decomposition rates. So far, it has been known that the mechanisms by which the diversity of litter affects decomposition results from biotic mechanisms mediated by the interactions between the decomposing fauna and the detritus. However, abiotic factors such as photodegradation also have a direct effect on decomposition rates in many ecosystems, especially in regions or habitats with a high incidence of UV radiation. In this way, it is conjectured that non-additive effects of the debris diversity in the decomposition should be weak or nonexistent under environmental conditions that do not favor the decomposition through biotic mechanisms. In this work, we tested this conjecture through two field experiments carried out under distinct environmental contexts, in a restinga in the State of Rio Grande do Norte. In the first experiment (Exp. 1), we verified whether and as non-additive effects of the richness and functional diversity of litter vary in magnitude and direction between a habitat more conducive to decay-mediated decomposition (ie soil under vegetation) and another where Photo-degradation-mediated decomposition assumes greater relevance (ie soil exposed to direct solar radiation). In the second experiment (Exp. 2), we observed only in the habitat with high solar exposure if and as the overlap (ie overlapping or not between) and the position with which the litter is vertically in the litter (ie in contact with the soil , or on the litter surface) measured the effects of the diversity of debris on decomposition. In the Exp. 1 litter of four species, presenting discrepant values of specific leaf area (AFE) were placed to decompose in monocultures and all possible bicultures over 6 months in litterbags. In Exp. 2 the decomposition was also evaluated in litterbags over 6 months, but only for monocultures and mixtures formed by two species that presented more discrepant values of AFE, Erythrina velutina (Ev) and Sterculia chicha (Sc). The results of Exp. 1 showed that the rate of decomposition at sites exposed to the direct action of photodegradation was on average 34% higher than that observed in shaded sites under vegetation. There was no significant effect of species richness on decomposition in any of the environmental contexts, indicating that on average the decomposition of the detritus mixtures can be predicted through the decomposition of their monocultures. However, this effect was not homogeneous among the bicultures. The functional dissimilarity between the bicultures had a significant effect on the decomposition, but only in the environment exposed to the sun. In general, combinations of foliar litter with greater discrepancy in the AFE values presented slower decomposition in bicultures than in monocultures. This result was mediated by a trade-off between effect and response of the debris of different species to shade. Species with higher AFE were more sensitive to shading, while species with lower AFE had a greater shading effect. In addition, in Exp. 2 we observed that the overlap and vertical positioning of the detritus also modify the effects of diversity on decomposition. Effects of the debris diversity on decomposition occurred only in the treatments with overlapping litter. However, the effects were significant only for the S. chicha (Sc) species, whose decomposition in the near-soil (less exposed to the sun) and surface (more exposed to the sun) differed from their monoculture decomposition (ie major and minor respectively ). Contrary to our expectations, abiotic mechanisms from photodegradation determine non-additive effects of the functional diversity of debris that consistently retard decomposition in environments exposed to the sun, but such effects have been shown to be dependent on the vertical position of the debris in the litter. Together, the results show that the functional diversity of the detritus, as well as factors that determine the vertical position of the debris in the litter (ie phenological pattern) can act as important mechanisms of carbon retention in the soil in regions, ecosystems or habitats, with high exposure solar

Knowing the situation of fish stocks is essential for the management and maintenance of fisheries. However, in Brazil little is known about most stocks, even those of interest to small-scale fisheries. In the absence of this information, historical surveys using interviews with fishers and other groups of people that directly observe fishing resources (e.g., researchers and divers) serve as a tool to evaluate the actual trends of these stocks. Nevertheless, there may be a common distortion associated with this methodology, known as the shifting baseline syndrome. In this syndrome, the informant tends to believe that the moment he or she began to observe the resource, the resource was at its peak of abundance, which disregards past exploitations and can lead to a false perception of the current state of the stocks. One way to alleviate this distortion is to include informants of different ages and experiences, seeking to retrieve the oldest information possible. The general objective of the present research was to do a historical survey of the sighting of some species of sharks by artisanal fishers on the northeastern Brazilian coast, evaluating possible changes in shark occurrences and their sizes along the last six decades, using for that information provided by artisanal fishers. The data were collected along part of the northeastern coast (states of Rio Grande do Norte, Paraíba, Pernambuco and Bahia). Out of the eight species analyzed, in three (Carcharhinus leucas, Ginglymostoma cirratum and Sphyrna lewini) the fishers perceived a decreased in their maximum size over the years. Coastal species were the most likely to suffer from these size variations. The different groups of fishers, classified into age groups, had different perceptions of the average sizes of the species Carcharhinus leucas and Isurus oxyrinchus. With the ever-increasing risk of extinction of large predators, we hope to contribute to the understanding of the patterns of abundance and size changes of fish and their stocks over the recent past through the knowledge accumulated by fishers.

Extractive Reserves are conservation units whose objective is to guarantee the sustainable use of natural resources by traditional extractive populations. The Acaú-Goiana Extractive Reserve is located in the estuary of the Goiana river, on the border of the states of Paraíba and Pernambuco, and involves areas of Atlantic forest, restinga, mangroves and apicums, being an important supplier of fishery resources such as Goiamum (Cardisoma guanhumi LATREILLE, 1828). The goiamum inhabits mainly the transition areas between the mangroves and areas of forest or restinga, known as apicuns. Due to the intense fishing exploitation and the marked degradation of its occurrence, C. guanhumi has been included in the list of endangered species, which imposes a series of restrictions of use and management measures aimed at the recovery of the populations and their habitat. Thus, the present work aims to analyze the population and fishing dynamics of the species, comparing areas of family farming (very common in the reserve) and preserved areas, aiming to subsidize effective management measures for the species in a territory with multiple anthropic activities. To date, 1619 burrows were sampled in the area and 500 animals were analyzed in the laboratory. The results indicated that there were significant differences between the two sampled areas in relation to the abundance of occupied burrows (ꭓ² = 12,929, df = 3, p <0.01), as well as in the carapace width - CW (ꭓ² = 1,186, df = 1, p <0.001) and weight (ꭓ² = 34,950, df = 1, p <0.001) of the subjects. However, there were no differences in burrow densities, abundance of empty burrows, moulting, and captured animals. There was also no difference in gonadal maturity size, LCxPeso ratio and condition factor between areas of agriculture and preserved areas. C. guanhumi is a generalist species, able to survive in environments altered by humans. However, management measures are necessary in relation to the zoning of agricultural activities, as well as the techniques and types of cultivation, which minimize the suppression of habitats and allow a greater growth and conservation of the species.

Intertidal rocky environments are important feeding, growth and reproduction areas to a variety of benthic organisms, including molluscs and echinoderms. They can be found worldwide and their benthos’ composition and temporal and spatial patterns are influenced by environmental and biological factors. Nevertheless, most studies on these environments have focused on rocky shores of temperate and subtropical regions. On the other hand, there is a lack of studies in other rocky formations and tropical regions, specially testing proper methodologies to their unique characteristics. This study had three main objectives: 1) to identify the main types of method used for quantifying benthonic organisms, through scientometric analysis; and, in tropical sedimentary reefs: 2) to test random and stratified quadrats and transects with quadrats to test the survey method that best represent richness of molluscs and echinoderms in these environments; 3) and, after defining the most suitable survey method, to test which environmental factors influence occurrence, abundance and richness of these organisms, and testing whether these is seasonal variation of occurrence of species. The organisms’ mobility is one of the determinant factors when choosing benthonic survey method. Quadrats and transects with quadrats were the main methods used to delimit areas of countage of mobile individuals and estimation of sessile cover. Random transects with quadrats showed better richness results with less collection effort, including sampling under boulders when they were present. Substrate cover, reef typology, habitat complexity and exposure time were the main environmental factors determining the structure of communities over the reefs. Substrate cover, habitat complexity and exposure time were the main structurers of communities under boulders. The abundance of organisms of the studied communities varied between dry and rainy stations, although this only occurred within a few taxa. 

Precipitation events and water level fluctuations are environmental factors that affects aquatic ecosystem functioning influencing phytoplankton dynamic and their resources. Nutrient availability and trophic state of arid and semi-arid regions are controlled by quantity and rain periodicity. Future climate scenario predicts an increase in intensity and frequency of droughts in semi-arid regions. Drought leads to water level reduction and consequently increase nutrients concentrations, turbidity, salinity and conductivity, favoring cyanobacteria blooms. However, recent studies shows that mixotrophic algae can be better competitors under more extreme conditions, such as prolonged periods of droughts. Mixotrophic organisms play important role as producers and consumers reflecting in the structure of food webs. In this work, we evaluate the effect of precipitation gradient in semi-arid region on the structure of phytoplankton community based on a trait-based approach. We confirm the hypothesis that in dry period the main phytoplankton traits are related to a high cyanobacteria biomass (nitrogen fixation, filaments, coloniality), however, in extremely drought periods with critical water level, cyanobacteria collapse and shifts the dominance to mixotrophic algae. To confirm that the reduction on light availability caused by sediment resuspension was the main factor on phytoplankton pattern, we performed laboratory experiments with competition between cyanobacteria and a mixotrophic species, manipulating light and sediment addition in systems with high levels of nutrients. Besides this, we also performed grazing experiments to estimate bacterivory by flagellate algae in distinct light and nutrients conditions and propose new methodologies to facilitate ingestion rates quantification. Our study shows the importance of mixotrophic algae in eutrophic environments, such as semi-arid systems affected by hydric deficit, and compare methodologies in order to facilitate bacterivory rates quantification, allowing a better knowledge about this kind of mixed nutrition. Therefore, research about mixotrophy implies in paradigmatic changes in how we understand aquatic food webs nowadays, in particular this is even more critic when it links to shifts in environmental conditions in a changing climatic world.

Fishes are important to uptake processes as well as energy and nutrients transfer in aquatic food webs. Fish excretion supplies nutrients for autotroph organisms, representing the main source of nitrogen and phosphorous for primary producers in several freshwater ecosystems. Body size, diet, as well as environment light-nutrient conditions, affect excretion rates and ratios of nutrient recycled by fish. The Amazon basin encompasses the most diverse fish fauna in the world, however nutrient recycling by fish in that ecosystem had never being surveyed so far. The main purpose of this thesis was to assess nitrogen and phosphorus release by fish, measuring their excretions in field conditions. One hundred fifty-three incubation experiments were performed using 59 native species. This thesis is structured in five sections: the first one presents a general introduction; the second section describes the study area, and methods used to get field data and the laboratory analysis; The third section deals about the results, which are presented in form of two independent chapters, each one with a brief contextualization about the problem addressed, results and discussion. The fourth and fifth sections, respectively, present a general conclusion and all the references cited. The main two results showed that: 1) excretion rates were negatively related to body mass and body stoichiometry, while excreted N:P ratio was positively related to body mass. We could reveal the indirect effect of body mass on excretion because body mass also affects body stoichiometry; 2) we used literature data to create a proxy to growth rate, assuming the fish growth is faster as smaller they are far from their maximum size, than we compared body stoichiometry and excretion ratios of juvenile in contrast to adult fishes. Results revealed that growth affects body stoichiometry and excretion ratios in the beginning of the juvenile phase. Overall, our conclusions point out that body size, body stoichiometry and growth affect N and P release by fishes.   

The establishment of patterns that explain latitudinal variations in avian life history is based on data from tropical rainforests, and there are gaps regarding the evolution of their traits in seasonal tropical environments. The strong seasonality of these environments is related to the rainfall regime, with wet and dry seasons well-marked. In addition, they have atypical climatic variation, exhibiting cycles with prolonged dry periods. As consequence, they limit the availability of food, shelter and nesting sites, altering the dynamics of bird populations. The effects of these periods reflect what is to come in a scenario of global climate change, where is foreseen the increase of shorter rainy seasons. Thus, it is important to understand the strategies of bird populations to keep up with seasonality, and how they respond to severely dry periods, especially granivorous, which are among the most abundant species in such environments. The Caatinga is an example of a tropical seasonally dry ecosystem. This domain presents a variable and stressful rainfall regime, where in many regions annual rainfall does not exceed 500 mm. Therefore, the aim of this thesis was to estimate population and reproductive parameters of granivorous birds in a Caatinga area, during and after a severely dry period. We developed the study at the Estação Ecológica do Seridó, city of Serra Negra do Norte, RN, Brazil. The thesis is structured in three chapters. In Chapter 1, we estimated detection and survival rates of the passerine Ammodramus humeralis. We tested the hypotheses that apparent survival would be lower than that described for tropical rainforests, influenced by seasonality and negatively affected by the prolonged dry period. To analyze the data, we used Huggins' robust design model in the MARK program. Contrasting our hypotheses, the best fit model considered apparent survival as constant, and the annual estimates among those observed in rain forests. We believe that the population studied here was able to maintain a constant survival, even in the face of a period where resources were severely scarce, because they did not reproduce. Since reproduction involves an energy cost, not reproducing compensates the waste that reduces survival rates. In chapter 2, we describe reproductive characteristics (egg size and weight, incubation and nestling period, nest density and behavioral traits) of Columbina minuta and Columbina picui. We also estimated nest daily survival rates (TSD) investigating whether the height, plant support, camouflage, stage (egg or nestling) and nest age influence this parameter. From it, we obtained rates of reproductive success and predation. We evaluated the hypothesis that TSD would be affected by environmental characteristics, higher during the nestling stage, and that predation would be lower than other orders species. We used the Mayfield method and developed nest survival models in the MARK program for data analysis. We verified that both species nest in several plant species at heights between 0 and 400 cm, and that only camouflage was an important factor in TSD. The estimates were higher during the nestling phase, corroborating our hypothesis. Predation was the main cause of losses, however with rates similar to those observed for species of other orders and other environments. Our results contribute to a better understanding of the evolution of life history of birds inhabiting tropical regions, since the existing pattern is based on data from rain forests. In chapter 3, we estimated detection rates and abundance of C. minuta and C. picui in two different physiognomies. We evaluated the hypothesis that the density is higher in the open physiognomy, that the species are more abundant during the wet season, and that they are able to perform regional movements. For analyzes, we developed Huggins’ closed population models in MARK program. The results corroborate our three hypotheses. The population size suggested greater abundance in savanna shrub and during the wet season. Recoveries of C. minuta in other Caatinga localities, combined with low capture and recapture rates, and low fidelity to the sample areas, indicate that nomadism can be the main strategy adopted by this species to maintain its populations in face of the climatic unpredictability of the Caatinga. The present thesis presents unprecedented results regarding the natural history of birds inhabiting tropical seasonally dry environments. In addition, it contributes to the understanding of the strategies adopted by granivorous species to maintain their populations in periods of severe resource scarcity, which will be much more frequent in a climate change scenario.

Fisheries science is characterized by several knowledge gaps that prevent the development of more sound research for fish stock conservation. Understanding how these stocks are spatially distributed and which genetic and environmental characteristics explain this distribution is crucial for fishery planning. In this thesis we describe conservation status, population genetics structure and connectivity, and effective population size of commercially important marine fish in Brazil. The first chapter presents an analysis of catch data for 132 species for 61 years. The results indicate a complex interaction between climatic and biological factors, besides exploitation type, affecting the species collapsing risk. The second chapter, using COI and CytB mitochondrial markers analysis, we identified the population genetics structure and historical demography for 17 commercially exploited marine fish species. Most species presented a lack of environmental barriers to gene flow along the Brazilian coast. However, population structure of Pomatomus saltatrix and Cynoscion jamaicensis results indicate genetic discontinuity due to temperature changes and isolation by distance, respectively. The goal of the third chapter was to identify effective population size variability for two reef species – Lutjanus jocu and Sparisoma axillare – and test the influence of past climatic variability on population size changes. Sparisoma axillare population expanded until five thousand years ago and is mostly stable until today, with a population expansion justified by increase in suitable habitat. For Lutjanus jocu, results suggest that, after a period of population expansion, is has been stable for the last one million years. Habitat suitability for L. jocu is apparently stricter nowadays than in the past, but this change does not seem related to population size. Distribution range of L. jocu is larger than S. axillare (endemic to Brazil), so it might be less susceptible to regional climatic changes. In the fourth chapter, we identified which seascape characteristics explain genetic connectivity patters of S. axillare, by analyzing samples collected in six sites on the Brazilian coast and in the islands of Fernando de Noronha, Abrolhos and Trindade. The results indicate that only Trindade Island population is genetically distinct. We found that seascape factors, as bathymetry and oceanic currents, can be more important to explain genetic variation than geographical distance. The results of this thesis indicate an important effect of environmental variables, such as temperature, oceanic currents and depth, on the vulnerability, connectivity and population size of marine fish in Brazil. However, we found a low environmental effect on species population structure. Our results can be applied for marine planning in the region.

Top-down regulations in trophic chain depend on herbivore grazing traits and producers edibility. By actively selecting nutritious eukaryotic phytoplankton and rejecting toxic cyanobacteria, grazing copepods may contribute to cyanobacteria blooms dynamics. In tropical environments, for instance, copepods commonly co-occur with cyanobacteria blooms, raising the question whether they can facilitate cyanobacteria dominance. We experimentally tested the effects of two groups of copepods with different feeding modes – calanoid Notodiaptomus iheringi (active filter feeding) and cyclopoid Thermocyclops decipiens (raptorial feeder) – on the competition of an eukaryotic phytoplankton Cryptomonas and the filamentous cyanobacteria Cylindrospermopsis raciborskii. We assessed grazing in 1L batch cultures for seven days, starting with 10-fold initial dominance of Cryptomonas. Copepods demonstrated initial rejection of Cylindrospermopsis filaments, but while cyclopoids slightly increased grazing on cyanobacteria in extended experimental periods, calanoids reversed to clear more particles of cyanobacteria. Despite differences on grazing, both zooplankton shredded cyanobacteria filaments, reducing filament size in ~70%. We also performed experiments testing competition between phytoplankton that showed no interference on each other growth rates, assuring that results from grazing experiment are addressed to zooplankton feeding. Here, we demonstrated that copepod selectively avoidance of filamentous cyanobacteria Cylindrospermopsis is not constant. Copepods were able to decrease overall biomass and shorten filaments of prey. Copepods grazing may not be the most appropriate mechanism to explain filamentous cyanobacteria blooms. While environmental correlations due to long term monitoring are important and may reveal interesting trends, a mechanistic approach to understand trophic dynamics of separate different groups (i.e. copepods and filamentous cyanobacteria) is necessary. This is especially relevant in light of the more intense warmer and eutrophic world that will promote cyanobacteria bloom, and increase complexity of such interactions.

Changes in climatic conditions influenced by human activities have an impact on biodiversity. Modifications in species distributions can alter diversity patterns over time and space. The Atlantic Forest is a region of high primate vulnerability due to climate change. We will investigate how these changes, in optimistic and pessimistic scenarios, will influence the patterns of primate diversity in the Atlantic Forest. Specifically: i) where are the largest changes in species richness expected? ii) the spatial pattern of beta diversity will undergo homogenization or heterogenization? and iii) where are the major changes in species composition projected? We generated geographic distributions for species from current climate suitability models. The richest regions in species will be more concentrated on the coast of the biome and the richness will decrease in areas of ecotone. Changes in richness will occur predominantly due to species loss. Spatially, communities will be more heterogeneous in the future, with increased beta diversity. The heterogenization should be driven by the reduction of the area of species geographic distributions. In the future, ecotone regions, especially the central Atlantic Forest and the westernmost region, both in contact with Cerrado, will become more heterogeneous and will undergo great changes in species composition. The changes in the precipitation regime predicted for these areas influence the  primates diversity directly, due to the physiological tolerances of the organisms, and indirectly, through changes in the forest structure and resources availability. The results should be observed with caution, since there are sources of uncertainties in the projections. Nevertheless, we consider that the changes detected are underestimated because the projections were restricted to the known area of the species and the dispersion in the future is extremely compromised by the high loss and fragmentation of habitat in the Atlantic Forest.

The bird distribution in the environment is modulated by habitat complexity and seasonal changes in resource availability, characteristics whose understanding is essential for accurate inferences about how species use the habitat. In addition, interspecific interactions also affect the distribution and the way in which the species use the habitat and may be an important factor to understand the coexistence, especially between congeneric species. Here, we used occupancy models for one and two species to investigate how vegetation structure and interspecific interactions affect patterns of habitat use and co-occurrence in three sympatric species of the genus Herpsilochmus (H. atricapillus, H. pectoralis and H. rufimarginatus). The study was carried out in a forest remnant at the northern portion of the Atlantic Forest distribution (RPPN Mata Estrela), northeastern Brazil. For this, we performed point-count surveys in 80 sample units, in the dry and rainy season, and collected variables related to the vegetation structure. From this we created sets of occupancy and co-occurrence models and selected the best ranked for each species and combination of species. As results of occupancy models we verified that the species H. atricapillus and H. pectoralis had high occupancy rates (Ѱ > 0.89 ± 0.07), whereas H. rufimarginatus had moderate, which was higher in forest areas (Ѱ = 0.47 ± 0.34 - 0.68 ± 0.15). The density of trees was the most important variable in the occupancy of the species, but with positive effect on H. pectoralis and negative effect on H. rufimarginatus. Although the best model for H. atricapillus also includes tree density, the effect of the variable seems uncertain. The detection probabilities ranged from low (p = 0.19 ± 0.03) to moderate (p = 0.59 ± 0.05) between species. The co-occurrence models brought evidence that H. pectoralis is related with a decrease in H. rufimarginatus occupancy, which was stronger in restinga areas, while the detection probabilities were independent for both. In the other side, the presence of H. atricapillus positively affected the occupancy of H. rufimarginatus, mostly, in restinga areas. Finally, the occupancy of H. pectoralis was independent of H. atricapillus, but the detection was negatively affected by the presence of H. atricapillus. Our results indicate that the tree density is the most important factor in the habitat use by the species studied here. In addition, the occupancy pattern of H. pectoralis and H. rufimarginatus could be influenced by competitive interactions, which associated with different micro-habitat preferences may be modulating the coexistence among these species. In contrast, H. rufimarginatus may be benefiting from the presence of H. atricapillus by following mixed flocks, either by increasing foraging efficiency or by protecting themselves against predators, but more studies are needed to understand this pattern of aggregation among species.

Most of the ocean biomass is microbial, and picoplankton microorganisms, which consists of small cells (<3 µm), are central players of global nutrient cycle and C production. Heterotrophic bacteria, cyanobacteria (Synechococcus) and autotrophic picoeukaryotes comprise picoplankton and commonly dominate microbial abundance and biomass production in oligotrophic waters of low latitude oceans. Thus, evaluate temporal dynamics of these organisms is crucial for understand microbial stocks and fluxes in equatorial regions. Here, we performed monthly samplings between 2013-2016 at Equatorial Atlantic Microbial Observatory (EAMO) situated on the coast of RN state – Brazil, to evaluate variations in abundance, biomass and activity (bacterial production and respiration) of picoplankton assemblage; and to identify the environmental factors that may regulate it in a scenario of greater environmental stability, where rainfall marks seasonality. Our results revealed that seasonality expressed a weak influence on picoplankton assemblage considering abundance, biomass and metabolic activity, with exception of Synechococcus, which peaked during dry seasons. Heterotrophic bacteria dominated picoplankton during entire study period; and showed higher abundances in July months, as well as picoeukaryotes. Interannual influence related to El Niño (ENSO) event in 2015 was also evidenced for total picoplankton assemblage. Autotrophic picoplankton (Synechococcus + picoeukaryotes) contributed in average for 30% of total picoplankton biomass (in contrast with heterotrophic fraction), and for 58% of total chlorophyll a. Among environmental factors, salinity proved to be the variable that best explained the abundance of picoplankton, with greater abundances during periods of low salinity water. However, weak environmental relationships found may suggest a greater importance of biological interactions (as competition and/or grazing) leading to picoplankton fluctuations throughout the year.

Seabob shrimp Xiphopenaeus kroyeri has great economic interest in several regions of the Brazilian coast. Despite its importance, its life history is still poorly understood, making it difficult to assess the impact of fishing and climate change on the natural stocks of this species. In this way, the biology and the population growth and the reproductive biology of the species in Baía Formosa, RN were investigated. Besides the relation of its abundance with environmental factors. The shrimp were captured monthly from March / 2013 to February / 2015, in 6 sampling points. The individuals were measured, evaluated for sex and the stage of gonadal development. The environmental factors were obtained using a multiparameter probe, in addition to collecting pluviometric data and sedimentological material. The intra-population groups presented negative correlation with the hydrological variables of temperature and background salinity, water transparency and depth, while the young ones presented a lower degree of relation with the environmental factors. There was significant influence of background temperature, presence of algae and water transparency, with the total abundance of shrimp. Females presented larger sizes than males. Reproduction of the continuous type was observed, with higher reproductive peaks at the beginning of each year. The average length of the first gonadal maturation was 13.6 mm and 14.2 mm for males and females, respectively. There was an inversely proportional relation between the total rainfall and the percentage of reproductive females. Growth parameters showed larger females and showed lower growth coefficient (k), resulting in a longer longevity than males.

The global warming expected consequences for the Brazilian semi-arid region are increased evapotranspiration and reduced precipitation, increasing the hydric deficit and prolonging drought periods. This study hypothesizes that the increase in water deficit, increases the trophic state of semi-arid reservoirs and accordingly reducing the alpha and beta diversity of benthic macroinvertebrates and increasing the susceptibility of lentic aquatic ecosystems to the elevation of trophic state. Eutrophication coupled with a negative water balance driven by climate change tends to promote cyanobacteria blooms, increase salt concentrations and the reduction of oxygen in the water column, which may reduce the complexity of lakes and benthic communities, as this phenomenon acts as an environmental filter selecting species more apt to colonize these environments.To test our hypothesis, we compared the benthic macroinvertebrate communities between two sets of reservoirs located in two neighbouring sub-basins of the Brazilian semi-arid region with contrasting precipitation regimes. The two sets of reservoirs were compared between two periods (dry and extremely dry) to evaluate the effect of drought intensity on benthic macroinvertebrates alpha and beta diversities. The results show that drought intensification increases reservoirs trophic state, especially in the sub-basin with lower annual mean precipitation. However, Contrary to what was expected for the driest basin where the reservoirs presented worse water quality there was increase in benthic macroinvertebrates beta diversity, due greater environmental heterogeneity. Deterministic mechanisms may have been responsible structuring the communities in our study. These results imply understanding the structure of communities in  climate change events of semi-arid regions.

Recreational diving is a touristic activity fastest growing in the world, generating employment, income and contributing to the visibility of the importance of the conservation of the reef environments. Despite the socioeconomic advantages, when performed without control, recreational diving can cause negative impacts to the reef ecosystem. Several studies on coral reefs in the world have characterized these impacts by proposing management strategies and biological indicators for monitoring. The peculiarities of Brazilian reefs, with low coral cover and high seaweed and sponge cover, make it necessary to identify and define proper management strategies for this type of use. The present study aims to evaluate the impact of recreational diving causes in a Brazilian Marine Protected Area (MPA). The first chapter presents the survey of the main tourist destinations of recreational diving in Brazil, evidencing their similarities and the current state of research in which they are, regarding the impacts of recreational diving. The results indicate the growth of recreational diving in Brazil and its potential as a promoter of the conservation of reef environments. In the second chapter, it was characterized the behavior of recreational divers in an MPA in the brazilian northeast, quantifying the frequency of touches on the reef substrate related to the profile of the diver and characteristics of the type of diving performed. The average frequency of touches (FT) observed was significantly lower in the studied reef when compared to other studies on coral reefs in the Caribbean, Mediterranean and Australia. The variables that influenced the FT were: type of diving (scuba > snorkel), sex (men > women) and in the age group (above 50 years, higher than in the other age groups). The discussion in this chapter approaches how the physical characteristics of the place of study may have influenced the reduction of FT, as well as the posture of tourism professionals. The third chapter is under construction and deals with the impacts of recreational diving on the ichthyofauna and the benthic reef community, proposing appropriate indicators to the characteristics of Brazilian reefs. In this chapter, it is possible to observe changes in the richness, composition, biomass and trophic classes of fish, and analyze changes in substrate cover, biologic vulnerability, invertebrates’ megafauna and coral health in high and low use areas over two years. The fourth and final chapter approaches with the use of alternative methodologies in an Environmental Education (EE) project aimed at its effectiveness, focusing on the impacts that tourism promotes. The results indicate that the combination of scientific knowledge, local knowledge, use of media and visits to non-formal environment are fundamental to the effectiveness of an EE project. This thesis presents pioneers data on the impacts that recreational diving generates in Brazilian reef environments, effectively contributing to the management and development of sustainable tourism in marine protected areas.

Plankivorous and bentivorous fish are key drivers of phytoplankton biomass and water turbidity. Therefore, restoration techniques for eutrophic lakes based on the selective removal of these fish (or biomanipulation) have been developed and used with relative success in temperate lakes. The viability of these techniques in tropical lakes, however, is uncertain due to differences in fish communities in tropical and temperate lakes. For instance, in warmer lakes fish assemblages shows higher degree of omnivory. To evaluate the effects of omnivorous fish on phytoplanktonic biomass and turbidity in tropical lakes and their implications for biomanipulation, mesocosms experiments were conducted with two omnivorous species. Nile tilapia (Oreochromis niloticus Linnaeus 1758) is an exotic planktonic species that is able to filter-feeds on suspended particles, including phytoplankton and zooplankton. The curimatã (Prochilodus brevis Steindachner 1875) is a native bentivorous species that feeds on algae, detritus and microinvertebrates. The results of the experiments are presented in three chapters. The first chapter deals with the mechanisms by which each species affects planktonic production and water turbidity. The second chapter deals with the consequences of the interaction between the two species for turbidity and phytoplankton biomass. The density dependent effects of curimatã on aquatic communities and water quality are analyzed in the third chapter. The results suggest that, through different mechanisms, the two species contribute to phytoplankton increase and water turbidity and that theres no synergistic interaction between the effects of the two species. It is possible to conclude, based on the results, that the removal of tilapia and curimatã can be a viable alternative of biomanipulation in tropical environments.

Plant form and function depend on internal stimuli (genetics and phenotypic plasticity) as well as external stimuli (environment) that act in the leaf, stem, and root. Water shortages and poor-nutritional sandy soils in the coastal region are cited as the main external stimuli to plants in the Restinga ecosystem. It has been proposed that coordination among plant organs tends to increase with environmental harshness due to a decrease in the viable niche space and an increase in the costs to adopt ecological strategies out of this viable niche space. The first thesis chapter aimed to test this hypothesis in the Restinga. Pairwise correlations of 21 functional traits of 21 species revealed that the stem had greater internal coordination than the leaf organ. In addition, a multivariate analysis showed high independence between stem and leaves, suggesting that stressful environments do not necessarily have plants with high coordination between organs. These results were published in Ecology and Evolution. Functional coordination is directly linked to the success of plant occurrence and may interfere in the community organization. It is still not clear whether weak neutral effects can influence the distribution of functional traits, even though the community shows random patterns of compositional and phylogenetic structure. We address this question in the second thesis chapter. Functional variation in the community resulted from phenotypic responses of all species and individuals rather than particular sets of species or individuals, indicating environmental responses, but not strong patterns in the spatial distribution of traits. In this regard, we accept that the Restinga in the Northeastern South America is influenced by weak neutral effects. We concluded that occurrence and phylogenetic analyses may be insufficient for a complete understanding of the community and should be complemented with functional analyses. The manuscript was submitted to the Journal of Vegetation Science. A weak environmental response may result from low niche partitioning among species, which has been described as the main mechanism underlying the relationships between biodiversity and ecosystem processes. The third chapter assessed the extent to which biodiversity and the environment influence annual litter production, as well as the combined role of rare to abundant species. A path analysis showed that the canopy cover had the greatest influence on production, followed by species richness. Environmental factors had only indirect effects. In addition, the combined contribution of several rare species was lower than the contribution of a few common species. These results suggest that diversity is important not only in short-term and small-scale experiments in the temperate region but also in the plot-scale of tropical forests, mainly through the role played by common species. As a general conclusion, Restinga ecosystem has patterns that deviate from the ones expected in the literature, which highlights the relevance of its biodiversity

A Amazônia é composta em grande parte por florestas que nunca (ou muito raramente) são submetidas ao alagamento sazonal causado pelo pulso de inundação. Entretanto, uma grande parcela do Bioma é formada por áreas que são geralmente submetidas ao alagamento todos os anos no período da cheia dos rios. As florestas alagadas são reconhecidas como uma importante fonte de recursos alimentares para animais das florestas de terra firme adjacentes e estudos recentes demonstram que utilizadas por diversas espécies de mamíferos que buscam diferentes recursos quando as águas estão baixas. Neste sentido, o objetivo principal deste estudo é a identificação de como o pulso de inundação altera a forma de uso dos habitats de várzea e terra firme pela comunidade de felinos e demais mamíferos terrestres de médio e grande porte na Amazônia, além de discutir a importância das áreas de várzea para estas espécies. Complementarmente, discutimos o efeito das populações humanas na ocorrência de felinos em uma área de terra firme da Amazônia. Para isso, utilizamos em todos os capítulos a técnica de armadilhamento fotográfico, em diferentes áreas da bacia do Rio Purus, localizado no Estado do Amazonas, Brasil. No primeiro capítulo deste estudo, realizado em três Terras Indígenas Paumari, localizadas no trecho médio da Bacia do Rio Purus, testamos hipóteses relacionadas ao pulso versushabitat para três níveis: a comunidade de mamíferos de médio e grande porte em geral, três grupos funcionais (Carnívoros, Herbívoros e Edentados) e as espécies separadamente. Desta forma, foi possível compreender as especificidades das respostas dos grupos funcionais e espécies ao pulso de inundação. Aplicamos uma análise de ordenação NMDS sobre uma matriz de dissimilaridade de Bray-Curtis para toda a comunidade e para os diferentes grupos. Para apoiar a interpretação das ordenações, calculamos a dissimilaridade entre os Habitats a partir da técnica de SIMPER (Similarity Percentages) utilizando a distância de Bray-Curtis, que foi a mesma utilizada na ordenação NMDS. Agrupamos cinco modelos como fatores de pressão ambiental que representam fatores moduladores de resposta da comunidade, dos grupos e das espécies (Cota, Habitat, Cota:Habitat, Cota:Habitat:Fase e Nulo). A comparação e seleção dos modelos foi realizada por meio do Critério de Informação de Akaike. Neste estudo, registramos 6574 ocorrências de mamíferos, sendo 5177 (média = 0.573 registros/noite câmera) na Terra Firme e 1577 (média = 0.313 registros/noite câmera) na Várzea. No geral, a maioria das espécies apresentou mais ocorrência em Terra Firme do que em Várzea. O habitat foi o termo com maior importância para todos os grupos, no entanto, houve grande variação entre espécies que apresentaram respostas completamente diferentes em relação ao habitat. Esse padrão geral indica que, mesmo parcialmente, a exploração dos recursos temporariamente disponíveis na floresta alagada na fase terrestre afeta a distribuição e a abundância dos mamíferos nestas regiões. Para várias espécies, identificou-se uma diminuição do número de registros na Terra firme quando a Várzea está disponível. Conforme esperado, estes resultados indicam que a mastofauna utiliza a várzea quando disponível e que a composição de espécies pode variar ao longo do nível do rio. No segundo capítulo, procuramos entender como ocorre o uso do habitat por de felinos Amazônicos nos mesmos tipos de habitat do Bioma (Várzea e Terra Firme), quando a) ambos estão disponíveis ao forrageio, e b) como isto pode estar associado às flutuações na ocupação da terra firme durante as diferentes fases do ciclo hidrológico. Este estudo foi realizado na Reservas de Desenvolvimento Sustentável Piagaçu-Purus (RDSPP) e Reserva Biológica de Abufari (Rebio Abufari), pertencentes ao mosaico de Áreas Protegidas do 

baixo Rio Purus. Utilizamos 120 armadilhas fotográficas distribuídas em seis blocos de 20 câmeras cada, em áreas de terras firmes contíguas a áreas de várzea, totalizando 648 km2 de amostragem geral. As câmeras permaneceram ativas durante 483 dias contínos em áreas de terra firme e por um período de 162 dias nos ambientes sujeitos a alagação sazonal (várzeas), durante a época seca, quando o habitat fica disponível para forrageio dos felinos. Estimamos a ocupação de grandes felinos na paisagem de duas formas, sendo a) entre os diferentes habitats (várzea e terra firme) e b) entre diferentes fases do ciclo nos habitats de terra firme, visando detectar mudanças ao longo do ciclo, nas mesmas localidades, que pudessem indicar uma movimentação destas espécies para outras áreas. Para ambas as questões, utilizamos modelos hierárquicos baseados em máxima verossimilhança que lidam explicitamente com o problema das detecções imperfeitas.  Nosso esforço total de amostragem foi de 30174 dias-câmera, caracterizando o maior esforço de amostragem contínuo com armadilhas fotográficas para a Amazônia brasileira. Obtivemos 624 registros independentes das cinco espécies de felinos que ocorrem na Amazônia. Nossos dados demonstraram que as espécies utilizam estes habitats de forma distinta. Para onça-pintada e gato-maracajá, a ocupação no período de seca foi maior na várzea do que na terra firme. O oposto foi registrado para onça-parda e jaguatirica, que apresentaram maior ocupação na terra firme. Em relação as fases do ciclo, na terra firme, para onça-pintada, jaguatirica e gato-maracajá, a probabilidade de ocupação na terra firme foi diretamente proporcional ao nível do rio, onde quanto maior a cota (mais elevado o nível), maior a probabilidade de ocupação, que vai decrescendo conforme a baixada da água. Somente as onças-pardas não obedeceram este padrão, apresentando uma probabilidade de ocupação maior durante o período intermediário. Isso demonstra a grande importância das áreas de várzeas para a manutenção destas espécies ao longo do ciclo de vida. No terceiro capítulo, avaliamos o efeito da pressão antrópica e de variáveis de paisagem na ocupação de felinos em uma reserva de uso sustentável na Amazônia central. Nosso esforço total de amostragem (número de dias em que as câmeras permaneceram em funcionamento) foi de 2653 dias-câmera (x =53 + 24.41). Obtivemos 79 registros independentes de quatro das cinco espécies de felinos Amazônicos. Dentre as variáveis testadas para explicar as probabilidades de detecção e ocupação de felinos, a importância de cada uma foi completamente distinta para cada espécie, evidenciando que mesmo espécies de porte e hábitos semelhantes, não encontramos um fator principal dentre os testados que determinasse como as espécies utilizam o ambiente. Nossos resultados demonstram, ao contrário do esperado, que comunidades humanas não afetaram negativamente a probabilidade de ocupação da onça-pintada e da onça-parda. Apenas para jaguatirica, houve uma relação positiva entre a distância dos assentamentos humanos e a sua probabilidade de ocupação. Embora registros de abate de felinos sejam comuns na literatura, nossos resultados demonstram que essa interação conflituosa não afeta a ocorrência dos mesmos em áreas próximas às comunidades humanas residentes em áreas protegidas de uso sustentável na Amazônia.

One of the main goals of biogeography is to unveil the processes and mechanisms involved on the generation and maintenance of biodiversity over time and space. Accessing species’ genetic information, coupled with conceptual, methodological, and computational advances have revolutionized the comprehension of evolutionary process. These advances have enabled reconstructing the evolutionary history of species and testing diversification hypotheses (e.g. refugee, physical barriers, diversification time) in a refinement level that once was unfeasible. The diagonal of open formations stretches from northeast to southwest South America, encompassing three biomes: Caatinga, Cerrado, and Chaco. Historically considered species-poor biomes with no evolutionary identity, these regions have witnessed a change in paradigm due to increase of research and, currently, are recognized as holding high levels of richness, endemism, and unique evolutionary histories. However, tempo and mode of fauna diversification throughout this region are still poorly known and the debate remains largely open. This dissertation is composed of two chapters. (i) In the first one, we used a phylogeography approach to test the effects of historical events on the diversification throughout the diagonal of open formations using the lizard Polychrus acutirostris as study model. In order to reach this goal, we infer population structure, phylogenetic relationships between lineages, intraspecific genetic diversity, migration patterns, demography and the spatio-temporal diffusion history. Finally, we tested 12 diversification scenarios using approximate Bayesian computation (ABC). We recovered three non-overlapping lineages that are spatially structured in the Caatinga, northeastern Cerrado, and southwestern Cerrado. Diversification among lineages took place during the Neogene and was associated to a complex scenario involving simultaneous divergence, early stages of diffusion, symmetrical pattern of migration among neighbor lineages, distinct effects of physical and environmental barriers. (ii) The second chapter aimed to identify areas in the Caatinga biome where the genetic diversity is spatially restricted (Evolutionary Hotspots) and propose areas that should be protected in order to maintain the evolutionary history of those areas. For this purpose, we used available mitochondrial data for six animal species widely distributed in the Caatinga, including: three lizard species, one amphibian and one spider. We used an interpolation method to generate a genetic diversity surface for each species. Finally, we overlapped the genetic diversity surfaces of all species to determine areas that concentrate high genetic diversity. In general, southern, central and northwestern portions of Caatinga harbor the highest values of genetic diversity, despite being poorly represented within protected areas. Our results highlight the complex evolutionary history within the diagonal of open formations. Besides, we identified genetically diverse areas within the Caatinga that are of utmost importance for biodiversity conservation.

Com o crescimento populacional e a expansão das cidades, o processo de urbanização e sua influência sobre a biota local entraram no hall de estudos ecológicos. Áreas verdes em meio a prédios e ruas tendem a se comportar como ilhas, servindo de refúgios para diversas espécies. O presente estudo teve o objetivo de entender quais fatores (e.g. cobertura vegetal) determinam a estrutura das comunidades de borboletas frugívoras em praças públicas e qual a influência de grandes áreas preservadas (Parque das Dunas e Parque da Cidade) na dinâmica das borboletas nas praças. Além disso, averiguamos se as comunidades de borboletas em diferentes hábitats possuem diferentes características ecológicas. Foram selecionadas 18 praças em três categorias de distância para o Parque das Dunas: Camada 1 (0 a 1000 m), Camada 2 (1001 a 2000 m ) e Camada 3 (2001 a 3000 m). Em cada camada de distância selecionamos 2 praças pequenas (1000 - 3000 m²), 2 médias (3001 - 5001 m²) e 2 grandes (> 5001 m²). Três pontos dentro do Parque das Dunas foram escolhidos como área controle. Após 11 meses de coleta, foram registrados 635 indivíduos de 13 espécies de borboletas frugívoras. Nas 18 praças encontramos 475 indivíduos de 9 espécies, e nos três pontos no Parque das Dunas registramos 160 indivíduos de 12 espécies. O baixo número de espécies encontradas na cidade é reflexo de uma homogeneidade local consequente de uma matriz quase impermeável. Foi possível verificar que nos períodos de chuva, a abundância aumenta significativamente nas praças, revelando que, quando a precipitação aumenta, a matriz se torna mais permeável, permitindo o deslocamento dos indivíduos e até mesmo o aparecimento de espécies encontradas predominantemente em florestas. As curvas de rarefação mostraram que o Parque das Dunas abriga mais espécies do que as praças, e que a riqueza de espécies não foi significativamente diferente entre as categorias de distância para o Parque e nem entre o tamanho das praças. A composição de espécies também foi significativamente diferente entre parque e praças e os valores dos componentes da beta diversidade revelou que a comunidade de borboletas é dominada por aninhamento. Com a seleção de modelos, foi possível selecionar os melhores modelos que explicam a riqueza e abundancia das espécies nas praças. Para riqueza, o melhor modelo foi o nulo, seguido por número de árvores frutíferas. Já para abundância, dois modelos foram selecionados: o primeiro, com as variáveis árvores frutíferas, cobertura vegetal e distância para o Parque das Dunas. E o segundo, árvores frutíferas, cobertura vegetal, distância para o Parque das Dunas e cobertura vegetal do buffer de 100 metros. Esses resultados indicam que tanto o efeito local quanto da paisagem são importantes para entender a distribuição de borboletas em uma paisagem urbana e para que estratégias de conservação sejam tomadas corretamente. 

The decapod crustaceans represent one of the groups more plentiful and diverse in  marine environments in consolidated and unconsolidated areas. Constituent coastal regions are the major portion of human population density and, through direct and indirect actions, may negatively impact diversity and population structure and assembly. So, the study aimed to analyze the richness and seasonal and spatial crustacean fauna decapod accompanying the shrimp trawling Xiphopenaeus kroyeri, in city of Baía Formosa, Rio Grande do Norte, constituting an official first species list, with bycatch data of trawling, for the state and a distribution study. The field work were in the litoral regions of not consolidated in the municipality of Baía Formosa, monthly (March / 2013 to February / 2015), through a small fishing boat with a single type door net trawl, 6 tows georeferenced standardized time (20min), collected as being environmental variables susceptible to seasonal variation like water transparency (g / L), pressure (kPa), salinity (ppm), dissolved oxygen (mg / L), pH, temperature (° C ), rainfall (mm) and wind speed (m / s). Were captured total hum of 23,218 animals, which belong to Achelata, Brachyura, Caridea, Dendrobranchiata and Anomura, totaling 57 species, among them: Acetes americanus, Alpheus intrinsecus, Nematopalaemon schmitti Xiphopenaeus kroyeri, Litopenaeus schmitti, Callinectes ornatus and Petrochirus Diogenes, as the specie more abundant. Besides the new occurrence for state (Lysmata. cf. bahia), there are species with a lot of economic appeal, as Xiphopenaeus kroyerii, which got a greater abundance, showing the importance of preservation this area. For the other species, the result already expected for the region, since the animals described are found in regions with similar geographical features.

The species of Brazilian primates Callicebus barbarabrownae, Callicebus coimbrai e Sapajus xanthosternos are at risk of extinction. One of the causes of this scenario is the fragmentation of the areas of occurrence of these species in the Caatinga and Mata Atlântica. This study has as objective characterize the fragments with occurrence to each one of these three species, as well compare them with a) remaining presence in the landscape where each species is inserted; b) compare the three species about the characteristics of the fragments where they inhabit, considering the inherent differences between each species and each biome. To generate the forest fragments of the distribution area of each species and identify fragments with confirmed presence it was utilized records of occurrence of the species and images of satellite of the Normalized Difference Vegetation Index (NDVI) shared by Hansen at al (2013). To characterize the fragments were utilized several metrics of the landscape. These three species of primates usually occurred in small, regular and with complex borders fragments. However, when it was compared with their respective distribution areas, the three studied species usually occurred in fragments with bigger area and more complex borders, demonstrating that these primates do not occur by coincidence. To C. coimbrai the size of the nearest neighboring fragment showed as more important than isolation. Their fragments with occurrence have bigger rate of proximity than the fragments of the area of the distribution, what infer in a bigger presence of fragments in the matrix. Among the analyzed characteristics of the fragments, the form (perimeter/area and complexity of the border) was the most determined in the occurrence of these three species of primates in fragmented environments. After the form, the most important explanatory variables were area and isolation (to C. coimbrai). When the there species were compared, it was observed that C. barbarabrownae had inhabited smaller and more regular areas, with less complex borders and more isolated than other two species, possibly because of its inhabitation in Caatinga, when the other two species predominately or just occurred in Mata Atlântica. Callicebus coimbrai and S. xanthosternos showed fragments with similar occurrence about their characteristics of form and isolation, possibly because they have inhabited the same over-fragmented habitat despite that they have differences not only in the use, as in the requirement of resources. Thus, it was concluded that these three primates require emergency measures of conservation that consider the characteristics that determine the occurrence of these species and promote the protection, restoration, and connectivity of the areas with the occurrence of these species of primates.

Currently, habitat fragmentation has been one of the major factors in changing the physiognomy of landscapes and habitats. Understanding how this influences the dispersal and movement of animal species may be crucial for future, conservation and management projects, to take into account this type of behavior of the species. In this study, using as an experimental model a food guild of frugivorous butterflies, we tried to understand how species specialists in forest and generalist species move in a landscape where there is a fragment of Atlantic Forest and neighboring habitats with distinct characteristics of the original forest, a plantation of Acacias and a coqueiral, in different seasons of the year (dry and rainy). Using a capture-mark-recapture method and a multi-state mode approach, we observe that specialists individuals move less between habitats during the dry season and move more during the rainy season and that the reverse occurs with generalist individuals. It is concluded that the movement behavior of frugivorous butterflies depends both on the group (specialist or generalist) in which the species is, and on the season (dry or rainy), as well as on the preferential habitat. From now on, it is necessary to consider the o movement behavior and dispersion in future studies and conservation of the species projects

Protected Areas are the main strategy to protected biodiversity. Protected Areas are not equal and vary in their management objectives and level of human occupation. Brazil has 12 protected area's categories. Among those, "Environment Protected Area" (EPA, Category V in IUCN Classification), is the one with least restriction to human activity. This category has many critics, that argue EPAs should not be account as Protected Areas, as has defenders who argue that EPA belong to a “New Paradigm” of Protected Areas, aimed to reconcile biodiversity conservation and human development. EPAs has special importance because it covers a third of the protected land, and more than 60% on biomes such as Atlantic Forest, Cerrado, Caatinga and Pampa, and more than 80% of all marine protected areas. Therefore, understand the implementation, land cover and management patterns is crucial for Brazilian biodiversity conservation. We find levels of human occupation is low within EPAs if compare with the biome, especially if we consider only the biome that is not protected by other protected areas and indigenous
areas. Nonetheless, we found about 7 million people live inside EPA and that in 2016, Amazon biome was the only biome with more than 50% of forest land cover. We find that if we do not account for the area with anthropogenic use inside EPA, the total area cover by protected area in Brazil would go from 17,6% to 12,8%. We also found that
only 18% of EPA had a &quot;management plan&quot; and 45% had a "management council". Lastly, we recommend starting a discussion about specific management and support mechanism to the EPA category.

Marine fishery resources are of great economic, social and ecological importance, as they guarantee food security and make up a significant part of the population's protein diet. They are still responsible for social integration and income generation for many fishers and workers directly and indirectly linked to Sector. Small-scale fisheries are of major importance in developing countries. However, although it occurs to a lesser extent, small-scale fisheries also exploit stocks that require proper management. It is known that the impact of fisheries goes beyond the more commercialized species, since often non-target species are caught accidentally during the activities. To date, fisheries management is still ineffective, focusing on a single target species, ignoring habitat, predators and preys of species and other components of ecosystems. In this way, the present work intends to bring updated and relevant information that can be used to subsidize the proposals of policies of ecosystem management of the fishing activity. The first chapter combines scientific knowledge and fisherman's traditional knowledge in the ecosystem modeling of fisheries. The second chapter provides modeling of the small-scale fishing value chain, identifying stakeholder participation and how the economic benefits are distributed along the chain. The third chapter has as main objective to analyze economically the relationship between income dependence of small scale fishing activity and the different degrees of influence of tourism in coastal communities. The 4th and 5th chapters present an analysis that aims to describe the characteristics of the composition of landed species, aiming at a better understanding of the dynamics of the socio-cultural system that influence the capture of natural resources, with emphasis on the coastal environment. The methodologies presented here and the results obtained open the way for the discussion of the use of the ecosystem approach to fisheries in the elaboration of management plans.

Many lizards have acute visual systems with retinal photoreceptors that are sensitive to UV wavelengths, and display UV-reflecting color patches. In this study, we used UV full-spectrum reflectance spectrophotometry to collect data from Cnemidophorus ocellifer UV structural colouration. Using an arena-form experimental set, we obtained evidence for the role of UV signaling in sexual selection (mate choice and male-male interactions). Our results showed that UV chroma is important in female association preference, as females exhibit spatial preference for males of higher UV reflectance over males with experimentally reduced UV reflectance. We also found that, in staged encounters, C. ocellifer males with experimentally reduced UV reflectance were not more likely to lose contests than control males, but reflectance was negatively correlated with evaluation time. We also tested two male ornaments in C. ocellifer against morphological traits and physiological performance to assess whether colour signals are informative for male quality traits. We found that larger males had more intense short (UV) and medium wavelength chroma on dorsolateral eyespots and, in contrast, smaller-headed males had more intense UV chroma on outer ventral scales (OVS). We concluded that the same colour trait convey different messages depending on the body position of the signal, perhaps indicative of alternative signalling strategies. Moreover, higher brightness on OVS signals were associated with stronger bite force, being a reliable signal of fighting ability. These results suggest that there is a multiple signalling system in our model species. Finally, we modeled the visual system of C. ocellifer, snake and avian predators to access how colour patches appear to the receivers We found that there are colour dimorphism between sexes, with UV signals of males more conspicuous in reflectance and highly distinguishable from females to conspecifics visual system. UV signals were highly perceptible from body colouration and from natural background to conspecifics and less but still perceptible to predators, agreeing with sensory drive hypothesis. This thesis enlighten the role of sexual signals and their importance on intra and interspecific communications in lizards. Our findings support further studies on evolution and behavior and expand the knowledge on natural and sexual selections iniciated by Darwin.

We aimed to evaluate how the spatial scale influences the taxonomic and functional composition of phytoplankton in freshwater environments distributed along an arid gradient from the (humid region) coast to the countryside (semiarid region) of Rio Grande do Norte. Likewise, we also intended to verify (i) which factors (local or regional) determines taxonomic and functional β-diversity (Chapter 1); (ii) how the relationships between functional and taxonomic metrics (richness, evenness, diversity, and functional redundancy) vary according to spatial observation scale (lake or watershed) (Chapter 2); and (iii) how environmental gradients explain the variation of phytoplankton size and functional groups (Chapter 3). We collected samples in the subsurface of the limnetic region of 98 lakes distributed along 14 watersheds, between September and October 2012. The functional metrics were based on mixed traits, as surface, size, presence of mucilage and pigment composition (green, blue, brown and mixed) and type of life forms (colonial, filamentous or unicellular). Our results show that although the environment was spatially structured mainly by watershed, the importance of space in structuring phytoplankton increased with presented a slight increasing spatial scale. Phytoplankton community was structured by species sorting at the watershed level and by the region’s and watershed’s identity at larger spatial scale. The only exception was Piranhas-Açú watershed, in which space was already structuring the community due to the great distances between its lakes. There was a strong role of functional complementarity at the local level for structuring phytoplankton communities. Opposite to what we expected, functional β-diversity was not a good predictor of local factors. Once, functional redundancy became more influent at the metacommunity level. At the regional level, both approaches (taxonomic and functional) explaining almost the entire distribution of organisms and functional traits. A positive relationship was found between all the functional and taxonomic metrics of the community (richness, evenness, and diversity). Moreover, on the contrary of what we expected, only the functional-taxonomic richness relationship increased the power of explicability with increasing spatial scale. Although the functional redundancy index weighted by abundance presented low values, it increased slightly on average with the spatial scale and was inversely related to environmental heterogeneity. These results suggest a substantial role of functional complementary at local scale for structuring phytoplankton communities and the importance of the functional redundancy at metacommunity level to maintain local communities functionally. In general, there was an increase in the average size of the phytoplankton community, with a Cyclopoida and Rotifera biomass, and reduced light availability. The predominance of SPT repeated itself within each of the functional groups, except for the non-toxic unicellular algae with hard cell wall and the toxic filamentous algae for which intraspecific variation was more important than SPT along predator (Calanoida biomass) and resource gradient (total phosphorus), respectively.

Within this proposal, we aim to resolve the following issues: Are there differences in coloration between males and females of Tropidurus hispidus? Do females use color traits to choose between mates? Does male coloration predicts the outcome of agonistic encounters? For that, we will use as model system T. hispidus Spix (1825), the larger species of the Torquatus group. Lizards of this genus are diurnal, extremely abundant, heliophiles, sit-and-wait foragers, and territorials, occurring predominantly in open areas. We used a spectrophotometer to measure color variables and visual modeling using the visual sensitivity data of Podarcis mularis. This data was used to answer the first question. To answer questions 2 and 3 we performed two controlled experiments with size-paired males. The first, a female mate-choice experiment in which we put males in a terraria enclosure with three separated parts. We assigned each male to a compartment in which they did not have mutual visual contact. We assigned females to the third compartment that enables visual contact to both the males. The second, a agonistic interaction experiment among males, in which we put a pair of males in a single terraria enclosure for 30 min. During the experiment period we recorded behavioral displays in order to determine winners of each trial. Separately, we used color variables to differentiate males from females. Our first results clearly showed that T. hispidus exhibits sexual dichromatism and that it is perceived as conspecific. Of the eleven areas of the body used to compare males and females, nine showed significant differences. For the dorsal region and head, the red chroma is the variable that most discriminates males from females. While for the ventral region of the thigh, cloaca, flank, belly and throat the glow is the one that best distinguishes males from females. For the base of the tail the tint better discriminates. The UV chroma in the ventral region of the tail base also distinguishes the sexes. The visual modeling showed that these differences are perceived by another lizard, confirming spectrophotometry data. In the experiment of choice by the females the region and the variable that discriminated best chosen and not chosen were respectively thigh ventral and chroma 8. For the competition experiment between the males the belly and collar regions, as well as the blue, 3 And 8 chroma variables, better discriminated winners and losers. With this, we intend to have contributed to a better understanding of the evolution of the signal design and how the intra- and intersexual selections act in this process in T. hispidus.

Global climate change is expected to increase the frequency and intensity of drought events in arid and semi-arid tropical regions. Although dry spells have been natural weather events in these regions, increases in your frequency may have cumulative effects on vertebrate populations and communities, exacerbating the severity of resource bottlenecks. Vertebrates with high mobility potential such as birds respond in different ways to drought events: diet and behavior changes to explore alternative resources, regional scale movements to track food, and adjust the territory sizes to local availability of resources. However, more severe and prolonged droughts can reduce recruitment and increase mortality rates in populations of sedentary and specialist birds. Current knowledge about the effects of drought on the avifauna of arid and semi-arid regions have been based on studies in Australia and Africa, while few studies have been conducted in the Neotropics. The objective of this thesis was to understand how a community and populations of insectivorous birds responded to a prolonged drought in Caatinga, between 2012 – 2015. Data were collected in Estação Ecológica do Seridó – RN, through systematic mist-netting in a seasonal frequency. Birds were captured in two grids of 12 ha with 48 sampling points each, established in two habitats: wood and shrubby caatinga. The captured birds were marked with aluminum bands and an individual color-combination of plastic bands. In the first chapter, we used capture-marking-recapture/resighting analysis to test the effects of habitat, precipitation, seasonality and of an unusually dry period on the monthly survival rates and population densities of four insectivorous passerines. Monthly survivals of Myiarchus tyrannulus, Hemitriccus margaritaceiventer and Polioptila plumbea fluctuated seasonally throughout the study, with the lowest values recorded in the dry intervals. Formicivora melanogaster survived constantly throughout the study. Annual survival rates of H. margaritaceiventer and F. melanogaster were markedly low in wood caatinga compared to shrubby caatinga. Densities of populations were higher in shrubby caatinga over almost all monitoring, and peak density in three of them occurred just after the rainy season of 2013, which followed the driest period of the study. In the second chapter, we used multiple-season occupancy models in a community approach to estimate the relative species richness in each sampling session, colonization, and local extinction rates during the intervals between sessions. Additionally, we tested for variations related to time, habitat, and functional groups. Relative species richness or the ratio of species at the study site to the number of species in the regional pool remained low throughout the study (20% – 51%), with higher estimates in shrubby compared to wood caatinga, ~ 42% vs. ~ 31%, respectively. Pollinators, seed dispersers and ecosystem engineers were characterized by colonization rates of less than 50%, and median to high extinction rates (40% – 60%), suggesting low fidelity to the study area. In contrast, granivorous and insectivorous species were resident in the community, with both low colonization and extinction probabilities (< 30%). Finally, in the third chapter we estimate territory sizes of Formicivora melanogaster during six resighting campaigns. We tested for the effects of habitat and relative air humidity (proxy of food availability) on territory sizes through an analysis of covariance. Between October 2014 and June 2016, we monitored six adult pairs and mapped 15 territories, whose estimates ranged from 0.52 to 3.94 ha. Territory sizes were inversely correlated with relative air humidity (F = 42.07; p < 0.01) and significantly higher in wood than shrubby caatinga (F = 14.53; p < 0.01), suggesting that adult pairs of F. melanogaster adjusted their territory sizes to the availability of resources in time and space.

Interações entre plantas cumprem um importante papel modulando comunidades vegetais. Os efeitos que um individuo exerce sobre seus vizinhos depende das suas alterações nas condições ambientais e na disponibilidade de recursos abióticos em seu entorno, resultando em interações positivas ou negativas. Interações negativas são evidenciadas em ambientes amenos e ao passo que o estresse aumenta, interações positivas tornam-se comuns. Ao longo do histórico evolutivo as plantas desenvolveram diferentes atributos funcionais para lidar com o estresse, deste modo, mesmo em ambientes mais estressantes, o resultado da interação depende das características das plantas que interagem, em um processo espécie-específico. Este trabalho testou a especificidade das relações das espécies arbóreas do semi-árido tropical, e se os atributos das espécies podem prever os resultados negativos e positivos. Foi conduzido um experimento com 20 espécies de plantas adultas (nurses) e 3 espécies de plântulas (targets) ao longo de 85 dias. As relações se mostraram amplamente espécie-específicas, variando com a identidade das espécies, e em diferentes medidas de desempenho para as targets. Os atributos funcionais das nurses foram importantes para apenas uma espécie de target, demonstrando que o resultado da interação varia tanto com as características das nursesquanto das targets. Medir os efeitos que uma espécieexerce na comunidade é fundamental para tomadas de decisão em programas de restauração. Os índices propostos na literatura medem as interações nurse-targetde forma pareada, não representando com eficiência os efeitos de uma nurse. Neste sentido, apresentamos um novo índice teórico que integra os efeitos da nurse em suas múltiplas relações, e comparamos os resultados com um índice pareado através de simulações. O novo índice evidencia os efeitos que acreditamos ser importantes para avaliar o impacto biológico de uma espécie, mostrando-se uma boa ferramenta em potencial para compreender as interações entre plantas a nível de comunidade.

A Caatinga é uma formação florestal esclerófila, decídua e espinhosa. Situa-se em uma região semi-árida, com cerca de 730 000 km2, exclusiva do território brasileiro. Este ambiente apresenta grande variação de tipos de vegetação que foram atribuídas à variações em larga escala no clima, padrões de geomorfologia e diferenças de pequena escala em relevo e solos. A precipitação escassa e flutuante das regiões áridas e semi-áridas, exercem um forte controle sobre: histórias de vida, características fisiológicas e composição de espécies de sua biota. Pelo menos 77 espécies de morcegos das 178 espécies presentes no Brasil são encontrados na Caatinga, dos quais 13 são frugívoros e cinco nectarivoros incluindo o endémica Xeronycteris vieirai. Os morcegos são conhecidos por desempenharem papéis importantes no controle de pragas, polinização e dispersão de sementes. No entanto, pouca informação foi gerada sobre o papel ecológico dessas espécies em um ambiente como Caatinga. Em geral, esse habitat é o ecossistema brasileiro mais negligenciado em termos de pesquisa e conservação da sua biodiversidade. Especificamente no caso dos morcegos, o Rio Grande do Norte possui uma das maiores lacunas de conhecimento no Brasil. Os dados aqui apresentados, representam uma das primeiras pesquisas formais com morcegos na Caatinga do Rio Grande do Norte. Foram geradas informações sobre a estrutura aninhada e assimétrica da rede mutualística entre morcegos nectarívoros e espécies chave de plantas para a manutenção da comunidade de morcegos nectarívoros nesta região. Além disso, a primeira evidência de folivoria de pelo menos 16 espécies de plantas pelo morcego frugívoro Artibeus planirostris foi documentada. Isto representa o primeiro registro para um ambiente semi-árido e o primeiro registro para a espécie. Finalmente, o primeiro “insight” para aspectos biológicos do morcego endêmico X. vieirai, incluindo dieta, poleiros e dados de reprodução, assim como a extensão de sua distribuição a nível nacional.

Apesar da rápida expansão nas últimas décadas, o cultivo de macroalgas ainda não atende à demanda das indústrias por material algal. Neste sentido, é necessário desenvolver protocolos que possibilitem a implantação de cultivos comerciais e evitem a sobre-exploração dos bancos naturais. A propagação vegetativa e o cultivo sob pulsos são métodos que permitem minimizar custos e produzir uma grande quantidade de propágulos de maneira sustentável. Este estudo teve como objetivo avaliar o crescimento de propágulos de Gracilaria birdiae cultivados sob pulsos de nutrientes. O estudo foi dividido em três experimentos: (1) indoor, (2) outdoor e (3) em campo. O experimento indoor, realizado sob condições controladas, foi conduzido em 12 aquários (10L) com água do mar filtrada e 40 propágulos de G. birdiae (~ 0,5 g/L). Os propágulos foram submetidos a três tratamentos, em triplicata, com pulsos de fertilização: (T₁) efluente de viveiro de camarão; (T₂) fertilizante para aquariofilia (Mbreda^®); (T₃) fertilizante extraído de Ascophyllum nodosum (Acadian^®). Uma série de três aquários (sem pulsos de fertilização) foi utilizada como controle. O experimento outdoor, onde os propágulos estiveram sujeitos às variações ambientais, foi conduzido em 12 aquários (30L), com densidade de aproximadamente 1 g/L de biomassa, e submetidos aos mesmos tratamentos descritos acima. O experimento em campo consistiu no cultivo dos propágulos dos experimentos anteriores (indoor e outdoor) no mar e em uma fazenda de camarão orgânico. Os valores positivos de biomassa e da taxa de crescimento em todos os experimentos evidenciam a viabilidade de produzir biomassa de Gracilaria birdiae da propagação in vitro até o cultivo em campo. Os propágulos cultivados no tratamento T₂ e no T₃ apresentaram os maiores valores de biomassa e de taxa de crescimento, assim como o maior conteúdo de nitrogênio. Isto indica que os dois fertilizantes possuem os nutrientes necessários e em proporções balanceadas para o crescimento de G. birdiae. Os propágulos cultivados na fazenda de camarão orgânico obtiveram valores de biomassa e taxas de crescimento menores do que aqueles cultivados no mar devido à maior variação da temperatura e da salinidade. Nestas condições estressantes, os propágulos do T₃ demonstraram desempenho superior em virtude dos compostos bioativos presentes no extrato de A. nodosum, os quais aumentam a resistência ao estresse abiótico. De acordo com os resultados obtidos, os propágulos apresentaram maior crescimento quando cultivados sob pulsos de fertilizantes e o protocolo desenvolvido pode ser aplicado para produção de estoques de propágulos.

A Caatinga é o único bioma cujos limites estão inteiramente restritos ao território nacional, sendo que ainda é tratada com baixa prioridade de investimento em conservação, sendo hoje uma das ecorregiões mais ameaçadas da terra, devido às altas taxas de conversão do uso do solo e existência de poucas áreas protegidas. O desmatamento tem sido o principal mecanismo responsável pela alteração do bioma. Essas circunstâncias despertaram nosso interesse para investigar o processo de expansão em número e área das unidades de conservação (UCs) da Caatinga, no espaço e ao longo do tempo; e avaliar a eficiência das UCs em evitar o desmatamento que ocorre no bioma, e de como a forma da UC e indicadores antrópicos da sua área do entorno influenciam o desmatamento que ocorre no seu interior. Atualmente 7,8% da área do bioma está sob proteção de 168 unidades de conservação. Não houve associação entre as esferas de gestão (federal e estadual) e o grupo de proteção das UCs, uso sustentável ou proteção integral, embora a dinâmica de criação de UCs na Caatinga tenha mudado ao longo dos anos, e siga tendências nacionais, como o aumento do número de UCs sob gestão estadual e de maior permissividade de uso, como as Áreas de Proteção Ambiental (APAs). As UCs de proteção integral foram as únicas que mostraram eficiência em conter o desmatamento que ocorre na sua área do entorno de 5 e 10 km, e as APAs foram as UCs mais suscetíveis às pressões de desmatamento externo. O desmatamento dentro das UCs está diretamente relacionado ao grupo de proteção a que pertencem. A forma da UC, densidade de estradas e proporção de vegetação no entorno das unidades de conservação não apresentaram relação com o desmatamento que ocorreu dentro dessas áreas.

The effects of fragmentation process and habitat loss have generally resulted in the decrease of species richness, abundance of species and density of species as well as changes in population distribution, in addition to decreasing genetic diversity. Knowing that the arboreal primates are the most sensitive species to habitat fragmentation and are dependent on forests, these factors affect them directly with decreasing size of the fragments, increasing the insulation level and edge effect, facts that can cause change in affecting habitat quality and often setting the permanence of these species in forest remnants. In this study we first assess the structure of the landscape in the sites where the two species of endangered primates of the Atlantic Forest in north of Rio São Francisco: Alouatta belzebul and Sapajus flavius. And then we compare the fragments in which these species occur in fragments that they do not occur with respect to aspects of the landscape. In attempt to try to understand why there is absence of primates in fragments with area and socioeconomic characteristics similar to those that have occurred these primates. The CPB (Centro Nacional de Pesquisa e Conservação de Primatas Brasileiros - ICMBio) provided the occurrence data of primates and use indexing basis of specific articles and journals to compile all articles in which these species were studied in the field. We use the forest cover data from the world generated by Hansen et al. (2013), and calculated for each fragment area, perimeter, shape, proximity index and ratio of forest cover the landscape. The species S. flavius has a tendency to occur in different fragments compared with fragments only A. belzebul occurs and that both species occur mainly when compared with the proximity index (which measures the distance between the fragments). Showing that the species S. flavius tends to occur in more isolated locations. The shape, perimeter and distance of cities were the main characteristics that most explained the absence of primates in fragments without occurrence with socioeconomic data and similar area of the fragments occurring primate. This result indicates that possibly primates have preference for fragments with less edge effect and probably are suffering by human action. Conservation strategies must be proposed as resettlement connectivity as corridors and "stepping stones". And awareness work with the people surrounding the fragments is required to maintain these species threatened with extinction still alive in the Atlantic Northeast.

Artificial eutrophication has been considered a problem of major concern in aquatic ecosystems around the world. Since 1960, scientific advances have been made in order to develop techniques that mitigate the effects of eutrophication. Several physical, chemical and biological procedures can be used and combined to recover lakes from cyanobacterial blooms, such as the application of a flocculant combined with natural or modified clay. However, the efficacy of local dryland soils in mitigating blooms is unknown for Brazilian manmade lakes. In this paper, we present a bibliometric analysis of the evolution of publications about cyanobacterial blooms and identify records that directly aim to overcome the occurrence of these blooms. Also, we evaluate, through laboratory experiments, the effect of the combined use of flocculent polyaluminum chloride (PAC) and a local soil from the lake catchment (LS), as ballast, in controlling cyanobacterial bloom in a shallow lake of the semiarid region of Brazil. The bibliometric research was conducted with the “Web of Science” database through the search function “TS = ((cyanobacteri* or blue green algae or cyanoprokariote or cyanophyceae) and (mass accumulation or bloom or domina*))”, from 1969 to June 2016. We performed a keyword frequency analysis and quantified the number of records with a restoration approach. Besides, three sets of experiments were performed in three sampling occasions with different bloom compositions and biomass in Armando Ribeiro Gonçalves Reservoir. Our study revealed that studies about cyanobacterial blooms increased exponentially and their quantitative impact on the aquatic sciences increased significantly along the years (F = 97.52; p < 0.0001). The USA stands out as the most productive nation, followed by China and European countries. China has impressively increased its contribution to this area, surpassing the USA in the last five years. Studies about Microcystis and toxins, such as microcystins, are trends in research, due to their ubiquitousness and historical negative consequences. We also emphasize the need for more studies aiming at developing techniques to solve and/or mitigate the issue of blooms. In view of this, our experiments revealed that the use of PAC and LS had a remarkable effect on cyanobacterial biomass in the water column in all samplings, reducing up to 90% top chlorophyll-a concentration. The use of LS alone was inefficient to settle blue-green-algal biomass. In two samplings, the combination of flocculant and ballast exhibited the same efficacy as the use of solely PAC. Even so, the use of LS is important to ensure sedimentation. Combined with PAC, LS was as efficient a ballast to remove cyanobacteria as a commercially available modified clay (Phoslock^®). Althugh LS in natura released considerable amounts of phosphorus and did not present P adsorption capacity, it managed to adsorb some dissolved phosphorus after organic matter was removed through muffling. This study shows that LS is a cheap, feasible and environment-friendly alternative to be used as a management action in reservoirs undergoing blooms in the semiarid region of Brazil.

A large number of sharks and rays inhabit tropical coastal areas. Unlike pelagic environments in the open sea, coastal areas are more subject to variations, both by human actions such as the continental, geographic or climatic influence resulting in a wide variety of habitats. Some species may have close relationship with certain habitats as to be possible to distinguish specific standards for different locations. Dasyatis marianae is an endemic streak of northeastern Brazil, occurring from Maranhão to the south of Bahia, exclusively on the continental shelf. With a restricted distribution, this streak showed estenotópica, with low amplitude tolerance to environmental conditions, especially temperature, salinity and depth. As a result, D. marianae presented morphological, ecological and molecular differences intraspecific over their geographical distribution. The more lanes south of the distribution are larger and have a distinct morphometric standard against the rays of the northernmost locations. Also, they have a lower genetic diversity and a greater preference for crustaceans in their diet. In general, D. marianae is divided into two populations genetically structures, a large population connecting the extremes of the distribution and a more restricted population located in Salvador. local environmental characteristics insulate this population, even without a physical barrier easy to identify. The pattern of population structure of D. marianae suggests an isolation by environment (IBE) where the interaction between the species and the habitat structure their spatial variation, regardless of distance. This work, based on an integrative approach (morphology, feeding niche modeling and phylogeographical) certainly generates grants for management actions and conservation of this species, according to Ordinance No. 43/2014 MMA, is a priority for research on your conservation state.

The geographical spatial of organisms' behavioral interactions to ecological niche spatially structured (ecological background) provides a 'living' point of contact between Ecology and Evolution. The production of cartographic bases promoted by multidisciplinary interface between Ecology, Behavior & GIS, are motivating, opportune and challenging scenario. For Primatology, the challenges of the products derived from that interface are mostly linked to the trade-offs between data accuracy and field studies restrictions. In this view, it is demanded quality certification metrics formalizing indicators of potential discrepancies of landscape structure data (imaging products) and landscape function (animal positioning) capable of compromising ecological and behavioral patterns with spatial dependence. In order to meet these demands, this Thesis aims to promote to Primatology tools of accuracy assessment and quality cartographic databases derived from remote imaging and GNSS positioning. To achieve the objectives were developed: 1. Theoretical Review with integrative approach to the body of the Thesis; 2. Evaluation of geometric correction models for high spatial resolution remote sensing images; 3. Evaluation of bias at GNSS positioning methods in forested areas, and 4. Evaluation of cartographic scale magnitude by modeled cartography products. The results of geometric correction modeling of satellite imagesshowed that antagonic scenarios (Google Maps without geometric corrections - optimistic scenario 1 and Geoeye sensor with robust ortoretifitcation methodsconservative scenario 1) are statistically equivalent (Turkey HSD: p = 0.95) and feasibility at the same work scale: 1./25,000 B-class (PEC-PCD95%) which allows working within error limited between 7.5 to 12.5 m. The GNSS positioning metrics in forested areas assessment showed three different patterns: 1. Horizontal accuracy independent of methodological complexity; 2. RTK method ineffective; 3. Vertical Accuracy dependent on carrier waves. It was also observed that the positioning methods C / A code, autonomous, GPS, instant (optimistic scenario 2) and post-processing carrier waves (L1 and L2) GNSS (GPS and GLONASS), and modeling of mitigating the effects of multi path (Floodlight technology - Trimble®) withing acquisition times of up to 15’ (conservative scenario 2) have the same cartographic scale in planimetric axis: 1 / 25,000 B-class (PEC-PCD95%). It is observed that the quality of cartographic databases derived from remote imaging sensors is dependent on the quality control data (DEMs: spatial resolution, accuracy; GCPs: number, accuracy, spatial distribution), while the quality of positioning by GNSS in forested areas is a nebulous issue due determination of control data. The results of this thesis demonstrate feasibility of geometric modeling for high spatial resolution remote sensors at low cost and equivalence of quality positioning data for low complexity GNSS in forested area in planimetric axis. The thesis deepening discussions about relations costs / benefits of the presented instrumental solutions and potential applications for Ecology, Behavior & GIS interface. Finally, it is concluded that this Thesis contributes the following perspectives: i. Presents in depth and adjusted to the profile of readers of Ecology, Behavior and Primatology problematic as the absence of formal instruments of management of cartographic databases and data quality indicators in Ecology, Behavior & GIS interface as well as state of the art of this instrumental ensemble; ii. Formalizes and evaluates instrumental models of generation and correction of cartographic bases of imaging sensors high spatial resolution and positioning GNSS in forested areas; iii. Respond to trade-offs between quality and feasibility of cartographic products in Primatology through optimal cartographic scale formalized by the indicators of the magnitude of errors.

Strategies to maximize conservation of biodiversity and ecosystem services in productive landscapes. Bringing ecology closer to territorial management.

Increased production and land use intensification is one of the most important pressures on ecosystems and their goods and services, with great impact in Latin America in recent decades. Appropriate land management policies to balance production landscapes with biodiversity conservation contribute to achieve the goals of development and sustainability, also top of agendas in all countries of the region. Easily applicable tools are needed to find ways of rural and urban sustainability in the political system.

Canelones department surrounds Montevideo –Uruguay’s capital— and has the highest concentration of farming areas compared to other departments. Accordingly, it is one of the departments with the greatest impact on natural ecosystems, due to anthropic activities and population growth, currently higher than national average figures. A state of environmental warning and strong pressures and threats to biodiversity was recognized, which currently extinct, endangered, or vulnerable species and several types of contamination detected.

The need to bring ecology closer to land management is a key to achieve a sustainable approach, and a great challenge to settle agricultural production with the conservation of biodiversity and associated ecosystem services (EESS). This thesis therefore proposed the following objectives: 1. Develop a territorial management model for Canelones that maximizes biodiversity conservation in production landscapes, addressing different landscape scales, and proposing appropriate environmental political and administrative management; 2. To investigate whether the productive land uses proposed by the Project AGUT: Fitness General Land Use (2010), are in accordance with the model 10:20:40:30 (Ch. 1), and if it is aligned with the objectives of sustainable development set out in the environmental agendas of the country; 3. Test if land surface of EESS mapped in Soutullo et al (2012) matches with the model, and estimate through the sale value of the land in the market, the cost to optimize the conservation of biodiversity and EESS in three scenarios: the model 10:20:40:30, AGUT (2010), and land surface of EESS of high conservation priority.

Chapter 1 compared the current land uses (OPP 2010) with the model proposed by Smith et al. (2013), which suggests a general framework to maximize the retention of biodiversity in an agricultural landscape: the 10:20:40:30 guide. A GIS was elaborated offering tools to apply in land planning at Canelones, in landscapes scales defined by political management boundaries.

The natural cover showed significant values lower the model, reflecting the pressure on natural ecosystems that exists in all landscape scales analyzed. The urgent challenge is increasing the natural soil surface. The potential management at different scales allows each locality to apply their strategies to recover natural soil, using natural parks, artificial lakes restoration, recuperation of riparian forests and wetlands. It also provides a planning framework for public and administrative policies.

Chapter 2 compared productive land use projected by AGUT (2010) reclassified on intensive, moderate, low and natural, and test if it fits the model (Ch. 1). A GIS was developed as a tool for land planning. The results showed that the projection AGUT ensures no sustainability at all.

The differences between both were significant, and the minimum of natural soil needed to promote conservation of biodiversity and associated EESS are not preserved. It would increase pressure on water resources and biological corridors of fluvial forest and riparian wetlands, intensifying land use in the entire territory, leading to a homogenization of the productive landscape through intensive and moderate land uses, and eliminating the possibilities of damping and environmental restoration, since no low land uses are proposed and natural cover

is taken to a minimum. With this intensive productive landscape proposal, the objectives of productive and sustainable development posed by AGUT project would not be achieved, nor the guidelines to the same purpose planned by departmental guidelines in Canelones, and also is not in line with the national legislation or national and international agreements that Uruguay has assumed as environmental targets to be attained in the millennium development goals.

Chapter 3 contrasted if the land area of EESS, with high priority conservation (Soutullo et al. 2012) matches the 10 % of natural cover of the model (Ch. 1). Moreover, through the market value of the land for sale, an assessment of costs was made to achieve the objectives of conservation and sustainability for Canelones, recovering it from the current scenario (Ch. 1), from AGUT (2010) (Ch. 2) and from EESS land cover. In the compared scenarios, at the departmental level, the EESS soil is greater (16,2%) than natural cover of the model (10%), although the results was wide-ranging in the other land scales analyzed. The 10% conservation of natural soil could arise as a conservation objective in the short and medium time. Moreover, reaching the EESS land cover could be a long-term goal, implementing management measures of that high priority surface to conserve. Economic valuation of natural cover of EESS provides opportunities to internalize and display costs in the economy. Indeed, cost estimates of achieving the objectives of 10% natural soil from the current scenario (OPP 2010), are less than the costs to get from the scenario posed by AGUT (2010), although higher are those to achieve the objectives of EESS land conservation.

The balance between productive and sustainable systems, conservation of biodiversity and water resources of Canelones, should consider including more precisely in territorial policies a balance between them. The model 10:20:40:30 proposed an optimization of production and conservation objectives, ensuring minimal natural cover, and a percentage of buffer land cover, as moderate and low, to maintain connectivity and reduce fragmentation (Ch. 1). Analyzed landscape scales also offer opportunities in regional planning from different administrative areas, providing more variety of occasions for management of natural and cultural heritage of Canelones. Moreover, the academic and social scenario is very favorable, and although there are usage conflicts and anthropic impacts, society is increasingly receptive to environmental issues.

Their participation is provided as fundamental and necessary to achieve sustainability goals in the long term.

A Plasticidade fenotípica em espécies de plantas tem se demonstrado um bom mecanismo para explicar parte da distribuição e ocorrência de espécies no planeta. Vários estudos vem sendo desenvolvidos para testar o papel da plasticidade em processos como invasão de espécies exóticas e expansão geográfica de espécies para locais heterogêneos, perturbados ou estressantes. Para tal, leva-se em consideração a capacidade de uma espécie em modificar suas estruturas frente à um ambiente independente do genótipo. Dentro do contexto da biologia do desenvolvimento, a literatura tem utilizado uma abordagem com linhagens de genótipos conhecidos, o que chamamos de plasticidade fenotípica strictu sensu. Por outro lado, estudos que tenham como foco aspectos ecológicos, tendem a assumir qualquer modificação do fenótipo frente a mudanças no recurso como plasticidade. Para esta abordagem ecológica, o termo utilizado é a Plasticidade fenotípica latu sensu, onde são incluídos e assumidos como mecanismos: normas de reação, variabilidade genética e a própria plasticidade strictu sensu, intra e inter específica. Neste caso específico, um bom delineamento na coleta de dados é fundamental para que não ocorra algum viés interpretativo. As características plásticas possuem uma grande importância adaptativa. Através delas é possível compreender quais estratégias morfológicas e fisiológicas permitem com que as plantas lidem com perturbações pontuais e com ambientes altamente estressantes. A compreensão destas estratégias pode trazer, além do melhor entendimento das comunidades naturais, uma ferramenta útil em programas de restauração. O semiárido brasileiro é um bioma altamente estressante, caracterizado por um forte filtro ambiental de estresse hídrico e altas temperaturas. Ademais, 53% de seu território já foi desmatado, e os métodos de restauração utilizados possuem baixa efetividade. A compreensão das estratégias de alocação de biomassa das plantas neste sistema é urgente para que esses métodos de restauração possam ser mais efetivos. Neste sentido, o primeiro capítulo desta tese busca compreender as possíveis relações entre padrões de plasticidade e a capacidade de espécies arbóreas serem bem sucedidas em programas de restauração. Pôde-se observar que espécies diferiram significativamente em sua capacidade plástica no que diz respeito à alocação de biomassa em raiz versus parte aérea. As espécies mais plásticas apresentaram em geral um maior potencial de sobrevivência em campo, demonstrando que a flexibilidade na alocação de biomassa, desempenha um importante papel em ambientes estressantes. Grime (1977) em seu trabalho clássico aponta 3 principais estratégias de captação e uso de recursos que plantas utilizam para lidar com diversas pressões ambientais: Ruderais, Competidoras e Estresse-tolerantes. Sabe-se que plantas Competidoras tendem a apresentar maior plasticidade fenotípica enquanto que em plantas Estresse-tolerantes a plasticidade é menos expressiva. Pouco se compreende sobre como estas estratégias de captação de recurso funcionam no semi-árido brasileiro. Da mesma forma, ainda permanece como uma lacuna entender se existe variação plástica das espécies com estratégias distintas em diferentes situações de disponibilidade de recurso. Por isto, no segundo capítulo buscou-se testar se características morfofuncionais dessas espécies vegetais estariam correlacionadas com suas estratégias de resposta à seca e se espécies arbóreas diferem nas suas estratégias de alocação em raíz e parte aérea quando enfrentam situações de estresse hídrico. Espera-se que as espécies “Competidoras” tendam a apresentar maior capacidade de realocação de biomassa frente as alterações abióticas do que as espécies com características “Estresse-tolerantes”. As estratégias de crescimento e alocação em raiz e parte aérea das espécies lenhosas estudadas diferiram de acordo com as disponibilidades de recursos. Algumas espécies apresentaram respostas de maior acúmulo de biomassa em raíz em relação à parte aérea quando irrigadas, outras apresentaram maior investimento em biomassa em raiz quando em tratamentos de seca. Em geral, a relação do investimento em raíz e parte aérea não demonstrou estar correlacionadas com características morfofuncionais de altura, SLA e densidade de madeira, no entanto, árvores mais altas se mostraram mais propensas a alongarem suas raízes em situações de seca. A diversidade de estratégias que possuem as espécies da Caatinga pode ser atribuída aos seus diferentes históricos de pressões, aliado ao filtro ambiental que a Caatinga exerce, modulando um grupo de estratégias que não podem ser completamente explicadas pelo modelo do triângulo do Grime (1977). A compreensão em larga escala de como os tipos de plasticidades morfológicas e fisiológicas e de parte aérea e raiz variam de acordo com fatores abióticos ainda não é clara. Por isto, no terceiro capítulo testamos se espécies que apresentam maior plasticidade fisiológica apresentam também maior plasticidade morfológica, se plantas são mais plásticas em atributos fisiológicos ou morfológicos e se o tipo de recurso disponível, seja este acima ou abaixo do solo poderia influenciar diferencialmente a plasticidade de alocação em raiz e parte aérea. Vimos que de modo geral não há diferença entre investimento de plasticidade entre atributos fisiológicos e morfológicos. Pode-se também verificar que existe diferença nos níveis de plasticidade entre espécies, porém aquelas que são mais plásticas em atributos morfológicos também o são em atributos fisiológicos. Adicionalmente, verificou-se que a alteração de um recurso de solo como água e nutrientes leva a uma maior alocação em raízes, enquanto que a alteração em recursos acima do solo como luz e CO₂ leva a uma maior alocação de biomassa em folhas e galhos. Esses resultados demonstram que plantas não só diferem em sua capacidade de serem plásticas frente às alterações ambientais, mas que também o seu maquinário fisiológico e morfológico evolui conjuntamente para expressar características plásticas. Adicionalmente, a plasticidade em plantas é usada como um meio de intensificar a captura de um recurso quando este se torna disponível.  

Beyond its importance in maintaining ecosystems, sharks provide services that play important socioeconomic roles. The rise in their exploitation as a tourism resource in recent years has highlighted economic potential of non-destructive uses of sharks and the extent of economic losses associated to declines in their population. In this work, we present estimates for use value of sharks in Fernando de Noronha Island - the only ecotouristic site offering shark diving experience in the Atlantic coast of South America. Through the Travel Cost Method we estimate the total touristic use value aggregated to Noronha Island by the travel cost was up to USD 312 million annually, of which USD 91.1 million are transferred to the local economy. Interviewing people from five different economic sectors, we show shark-diving contribute with USD 2.5 million per year to Noronha’s economy, representing 19% of the island’s GDP. Shark-diving provides USD 128.5 thousand of income to employed islanders, USD 72.6 thousand to government in taxes and USD 5.3 thousand to fishers due to the increase in fish consumption demanded by shark divers. We discover, though, that fishers who actually are still involved in shark fishing earn more by catching sharks than selling other fish for consumption by shark divers.  We conclude, however, that the non-consumptive use of sharks is most likely to benefit large number of people by generating and money flow if compared to the shark fishing, providing economic arguments to promote the conservation of these species.

Natural landscapes have been dramatically affected by habitat loss and fragmentation, which transform continuous forest in habitat patches imbedded in areas of non-habitat (matrices). This matrices, inhospitable or not, affect countless ecological process, like dispersal. One of the ways to understand this effect of matrix on dispersal is studying animal’s perceptual range. Which is a range at which an animal perceive landscape elements. This perception is directly connected to the success to reach a new habitat patch while animals navigate through matrix. To contribute to this knowledge we evaluate the habitat perception of Heliconius erato. However, we were also interest in evaluate the effect of butterflies age and matrix type on its perception. Consequently, we raised butterflies on laboratory and matched with butterflies from forest during a release experiment. To determinate perceptual range, we did releases in two different matrices at three distances from forest (0, 30 and 100 meters) and measured the final angle reached for butterflies. We found that: I) butterflies released in edge were strongly oriented to forest; II) than higher the release distance the lower perceptual ability and III) there is an interaction between age and matrix type. Naïve butterflies oriented better on open field (perceptual range: 30-100 meters and experienced oriented better at coconut plantation (perceptual range: 30-100 meters).

Duas espécies de borboletas miméticas Heliconius erato e Heliconius melpomene apresentam coloração similar. Tal similaridade pode atuar confundindo o reconhecimento de seus co-específicos no momento da escolha de parceiros sexuais. As duas espécies possuem um conjunto de variações sutis na cor de suas asas que são  compartilhadas por ambas espécies, como os pontos vermelhos encontrados acima da faixa amarela. Em H. erato variações na cor de suas asas são exclusivas da espécie como os red raylets e pontos amarelos na região distal da asa posterior.  Acredita-se que tais variações fenotípicas auxiliem no reconhecimento de seus co-específicos, para tanto, o presente estudo tem por intuito verificar se as duas espécies envolvidas na análise reconhecem seus co-específicos. Sendo, experimentos com modelos que contemplaram  variações sutis foram montados e apresentados aos machos de H. erato e H. melpomene. Em cada experimento foi verificado a probabilidade relativa de aproximação do macho ao modelo. O teste de likelihood indicou que as diferenças sutis encontradas nos padrões de asas de H. erato e H. melpomene podem atuar como pistas de reconhecimento de indivíduos da mesma espécie. Sendo que a espécie H. erato pode ser considerando um discriminador mais refinado no reconhecimento e ambas as espécies selecionaram modelos que possuem variações médias, indicando seleção normalizadora para a escolha do padrão de asa. Podemos concluir, que a cor e, principalmente, os padrões sutis na variação da cor são utilizados como um sinal usado por borboletas no reconhecimento de seus co-específicos.

Ao passo que os carnívoros são considerados importantes regulares e estruturadores das comunidades naturais, também são extremamente pressionados pela ação antrópica. Ameaçado de extinção, o gato-do-mato-pequeno (Leopardus tigrinus) é uma das espécies menos conhecidas entre os felinos neotropicais. Neste trabalho, investigamos a ocupação e o padrão de atividade de L. tigrinus na Caatinga, tentando entender que fatores ambientais e antrópicos afetam essa ocupação e como o padrão de atividade da espécie pode ser influenciado por fatores bióticos e abióticos. Para isso levantamos dados de ocorrência e do horário de atividade da espécie em 10 áreas espalhadas pelo estado do Rio Grande do Norte. Para modelar a ocupação, utilizamos modelos hierárquicos baseados em máxima verossimilhança que representaram hipóteses biológicas e foram ranqueados com o uso do Critério de Informação de Akaike (AIC). De acordo com os resultados, a ocorrência da espécie é maior distante de assentamentos rurais e em locais com maior proporção de vegetação arbórea. Desta forma, L. tigrinus parece ser afetado negativamente pela atividade antrópica existente nesses assentamentos e demonstra uma preferência por áreas do habitat com vegetação estruturalmente mais complexa. Analisando os horários dos registros da espécie através de estatística circular, concluímos que o seu padrão de atividade é majoritariamente noturno. Dentre os fatores testados, a atividade de L. tigrinus foi diretamente afetada pela disponibilidade de pequenos mamíferos terrestres, provavelmente, suas presas preferenciais neste ecossistema. Além disso, as temperaturas registradas no ambiente afetaram direta e indiretamente a atividade da espécie, já que também condicionam a atividade das suas presas. Os resultados encontrados nesta pesquisa melhoram o conhecimento sobre um felino ameaçado que habita a Caatinga, podendo assim auxiliar no desenvolvimento de estratégias de conservação e manejo da espécie, bem como no planejamento de pesquisas futuras neste ecossistema.

Abundância e riqueza de espécies são parâmetros centrais para ecologia e cruciais para medidas de diversidade e composição de espécies em um ambiente. Podem ser afetados pelas alterações, pela estrutura da paisagem e do habitat, que repercutem de maneira distinta entre os grupos taxonômicos promovendo perda de diversidade. Portanto, entender como esses padrões ocorrem é imprescindível para possíveis decisões sobre a conservação dessas espécies e seus ambientes. Diante disso, este trabalho objetivou avaliar a influência da alteração e estrutura da paisagem e do habitat sobre os lagartos com ênfase na Caatinga. Para isso, foram amostradas durante três meses sete áreas de Caatinga através do método de encontro visual por transectos. Ainda, variáveis da paisagem e do habitat foram registradas para avaliar como elas influenciam esse grupo neste ambiente, através da seleção de modelos. Nossos resultados demonstraram que a riqueza de espécies foi afetada pela complexidade topográfica de maneira positiva, assim como pela quantidade de afloramento rochoso. Este último também foi responsável por agrupar as áreas amostrais em três grupos dissimilares em relação à composição de espécies. A complexidade topográfica e o número de afloramentos rochosos afetam a riqueza de espécies de maneira positiva, devido à heterogeneidade ambiental que elas promovem no ambiente, permitindo as espécies refúgios, abrigos e locais para termorregulação. Além disso, áreas mais complexas topograficamente são menos suscetíveis às alterações e mais preservadas, apresentando maior diversidade. A composição de espécies, como registrado em outros ambientes, teve a estrutura do habitat como principal fator em agrupar as áreas amostradas. Isso corrobora nossa hipótese de que ela, através da heterogeneidade ambiental afeta os parâmetros de riqueza e abundância das espécies. Portanto, preservar esses ambientes através de unidades de conservação e de um zoneamento do uso da terra é de extrema importância para a manutenção da diversidade dos lagartos na Caatinga.