Banca de QUALIFICAÇÃO: ANDERSON DANTAS LEAL

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ANDERSON DANTAS LEAL
DATE: 23/03/2023
TIME: 08:30
LOCAL: Youtube (https://www.youtube.com/watch?v=0D9vmDUxmQs)
TITLE:

Ant diversity patterns at local, regional and global scales

KEY WORDS:

Biogeography; Communities; Restoration; Disturbance; Habitat loss.

PAGES: 103
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUMMARY:

Biodiversity is spatially structured following processes that act at different scales, for example, climate, anthropogenic disturbances, and biotic interactions primarily act at global, regional, and local scales respectively. Describing biodiversity patterns provides us with important information for determining current and future conservation protocols. However, given insufficient information on distribution and spatial biases, many taxa are neglected in conservation plans. Ants are involved in maintaining plant populations and soil chemical and physical conditions globally, but gaps in knowledge about the determinants of their global biodiversity patterns, and their responses to chronic anthropogenic disturbances and restoration, lead to uncertainties about the conservation of the group. In the thesis, we propose to investigate the determinants of ant diversity at three different scales, global (testing the effect of climate and topography), regional (testing the effect of anthropogenic disturbances), and local (testing the effect of plant diversity and facilitation). In this regard, the thesis is structured in three chapters: (1) the first chapter aims to test the relative strength of abiotic gradients in determining spatial patterns of ant diversity globally and across biogeographic realms. We use multiple regressions to relate global ant diversity data to climate and topographic data. Our findings indicate that ants are highly diverse in tropical regions, particularly in locations with higher annual precipitation and higher mean temperature. However, determinants between zoogeographic realms varied widely, challenging the generality of the overall pattern, and showing the importance of considering regional historical and ecological contexts when investigating biodiversity patterns. (2) In the second chapter we tested how chronic anthropogenic disturbances, general index or its vectors (e.g. logging), and acute disturbances (deforestation) influence total ant species richness, forest species richness, and generalist species in the Caatinga. To this end, we constructed a structured database from studies of ant diversity in the Caatinga under different disturbance scenarios and then juxtaposed multiple regressions to test the effects of disturbance vectors on ant diversity patterns. Overall, we found that habitat loss  deforestation) decreases species richness at any level (total, forest, or generalist), while the overall chronic disturbance index particularly affects forest species. In addition, to individual disturbance vectors (e.g. grazing), (3) The third chapter aims to test how plant diversity, tree facilitation, and the presence of plants with extrafloral nectaries affect ant diversity patterns (species richness, phylogenetic diversity, and abundance). For this purpose we sampled the ant fauna in 155 plots in the experimental area of the BrazilDry project, a biodiversity experiment set up in the Açu National Forest that has plotted with one, two, four, eight, and 16 plant species, with different compositions, and that has a facilitation gradient. Our results indicate that plant diversity is the main mechanism that explains the richness and phylogenetic diversity of ants in the BrazilDry experiment. Additionally, we found that ant richness, phylogenetic diversity, and abundance have a strong spatial organization in the experiment. Our findings are possibly related to a bottom-up effect in the trophic chain, when plants provide important resources for ants, increasing their diversity. With the thesis, we fill significant gaps in the biogeography of the world's ants, their determinants, and the responses of ant communities to positive and negative anthropogenic effects.

COMMITTEE MEMBERS:
Presidente - 1678202 - CARLOS ROBERTO SORENSEN DUTRA DA FONSECA
Interno - 1718346 - EDUARDO MARTINS VENTICINQUE
Interna - 1914239 - MIRIAM PLAZA PINTO