Banca de DEFESA: ANDRÉ LUIZ PARDAL SOUZA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ANDRÉ LUIZ PARDAL SOUZA
DATA : 11/08/2021
HORA: 14:00
LOCAL: por participação remota
TÍTULO:

Spatial integration of ecological patterns and processes on rocky shores: Influence of natural and anthropogenic factors

PÁGINAS: 192
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
SUBÁREA: Ecologia de Ecossistemas
RESUMO:

Understanding patterns of diversity, abundance and composition of species and identifying their drivers are the main goals of community ecology. Progress on such matter has elucidated the roles of (i) abiotic heterogeneity, (ii) species interaction, and (iii) the supply of ecological subsidies as central factors/mechanisms. Currently, it is widely accepted that the structure and functioning of communities are affected by mechanisms from these three ‘classes’ and, principally, their interactions over space and time. Despite major advances in understanding community regulation, there are still gaps in integrating ecological patterns and processes over multiple spatial scales. In face of a rapidly changing world, comprehending how biodiversity responds to the environmental context from local to global scales is a research priority. Here, I defend the thesis that environmental factors emerging at different spatial scales affect populations and communities, and mediate predator-prey interactions. My first goal was to investigate how environmental factors (biotic, abiotic, and anthropic) from different spatial scales affect populations and communities (Chapters 2-4). I carried out observational surveys in tens of sites along the Southeast coast of Brazil (SW Atlantic) using rocky intertidal organisms as models. The studied populations and communities varied mostly at the smallest spatial scales assessed (i.e., among-quadrats and among-sites). Such populations and communities were affected by environmental factors investigated. For instance, increasing wave exposure affected positively the abundance of several species. The body size of several species was negatively related to seawater surface temperature (SST). The composition of communities was also affected by wave exposure and SST. Such results confirm the importance of abiotic factors at different spatial scales affecting the structure of populations and communities on intertidal rocky shores. My second goal was to evaluate how the interaction between predators and prey is altered by environmental factors at different spatial scales (Chapters 5 and 6). Through manipulative experiments carried out in the field along the Southeastern coast of Brazil, I found that trophic interaction between a dogwhelk and a barnacle was locally mediated by the interactive effect of wave exposure and prey density. This research confirms that environmental harshness can decrease the importance of predators with density-dependent effects determining the magnitude. Large-scale gradients (SST and chlorophyll-a concentration), on the other hand, seemed to play a secondary role in this predator-prey interaction (Chapters 5). Finally, I investigated the effect of metal contamination on a predator-prey interaction from the temperate intertidal (west coast of Great Britain). Copper contamination increased barnacle mortality and reduced predation with no effects on interaction strength. Despite not affecting the interaction strength, these results suggest a decrease in energy flow in the trophic chain that may lead to important changes in community structure and ecosystem functioning (Chapter 6). In this thesis, I provide an extensive database on biodiversity and relationships to the environmental context at multiple spatial scales. The analyses and interpretations improve our understanding of the interactions between environmental variability and the structure and dynamics of populations and communities. In addition, my results point to future research directions that will advance our local understanding, while addressing current issues in international forums.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 196.959.548-55 - RONALDO ADRIANO CHRISTOFOLETTI - NENHUMA
Membro Titular - Examinador(a) Interno ao Programa - 1768895 - GUSTAVO MUNIZ DIAS
Membro Titular - Examinador(a) Externo à Instituição - PAULO DA CUNHA LANA - UFPR
Membro Titular - Examinador(a) Externo à Instituição - MARIANA BENDER GOMES - UFSM
Membro Titular - Examinador(a) Externo à Instituição - ANA CAROLINA DE AZEVEDO MAZZUCO - UFES
Membro Suplente - Examinador(a) Externo à Instituição - BÁRBARA LAGE IGNACIO - UNIFESP
Membro Suplente - Examinador(a) Externo à Instituição - FÁBIO CARRETERO SANCHEZ - UNIFESP