Banca de QUALIFICAÇÃO: WAGNER DE FRANCA ALVES

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : WAGNER DE FRANCA ALVES
DATE: 08/12/2021
TIME: 00:08
LOCAL: GOOGLE MEETS
TITLE:

SPATIAL PATTERNS OF BIODIVERSITY AND ECOSYSTEM STABILITY ALONG GRADIENTS OF URBANIZATION AND LAND USE

KEY WORDS:

Metacommunities; spatial scale; β-diversity; turnover; nestedness; biotic homogenization

PAGES: 84
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUMMARY:

Increasing anthropogenic pressures, mainly related to urbanization and agricultural intensification, have resulted in habitat loss and fragmentation, with consequences for biodiversity and ecosystem stability at different spatial scales. However, there is still limited understanding of how different taxonomic groups respond to these pressures and at what spatial scale these effects are strongest. Another uncertainty concerns the level of spatial and temporal incongruence in the different dimensions of biodiversity (i.e., taxonomic, functional, and phylogenetic). In this thesis, we primarily aimed at assessing how anthropogenic impacts affect patterns of species diversity and stability across multiple spatial scales. This was done using databases of hundreds of animal metacommunities, collected at high resolution and through international collaborations in several European countries. This thesis is divided into three chapters. In the first, we investigate how the relationships between dispersal ability and body size of six arthropod groups influence the relative amount of the β-diversity components: turnover and nestedness. Turnover represents a situation in which different species replace each other along environmental and/or spatial gradients, whereas nestedness reflects a situation where compositional variation results from differences in richness between communities, with less diverse communities being a nested subset of richer communities. For this type of analysis, urban gradients and multiple spatial scales were considered. It was found that groups with a positive size-dispersal links show a more pronounced nestedness pattern towards urban centers compared to groups with a neutral size-dispersal links, especially at the 200-meter scale. This result indicates that not only size is an important trait that selects species along the urban gradient, but that variation in dispersal ability also influences the organization of urban metacommunities, favoring good dispersers in fragmented cities. In the second, we are analyzing the patterns of spatial and temporal incongruence of different dimensions of biodiversity at a macroecological scale. For this, we are using abundance data of European butterflies collected over 12 years in eight countries, integrated with functional and phylogenetic data of the species. This information will be related to relevant environmental variables. So far, only the taxonomic approach has been analyzed and it was found that there was no significant change in the spatio-temporal β-diversity. This result indicates the absence of a taxonomic biotic homogenization in European butterfly communities over time. Finally, in the third chapter, using the same data as in the second, we aimed to assess how local species diversity and different facets of β-diversity influence the stability of butterfly abundance at larger scales. For now, and also using only taxonomic data, the asynchronous dynamics of species within local communities turned out to be more important than β-diversity for butterfly stability on a macro-scale. We believe that the inclusion of functional and phylogenetic data will improve the prediction of β-diversity, contributing more comprehensively to a better prediction of the consequences of spatio-temporal changes in biodiversity at different spatial scales.

BANKING MEMBERS:
Presidente - 3060333 - ANDROS TAROUCO GIANUCA
Interno - 1718346 - EDUARDO MARTINS VENTICINQUE
Interna - 1914239 - MIRIAM PLAZA PINTO