Biodiversity variation under contrasting disturbance regimes at multiple scales

• Grant number: 26/00846-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: March 01, 2026
• End date: February 28, 2030
• Field of knowledge: Biological Sciences - Ecology
• Principal Investigator: Tadeu de Siqueira Barros
• Grantee: Gabriela Dezotti Oliveira
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Associated research grant: 21/10639-5 - Center for Research on Biodiversity Dynamics and Climate Change, AP.CEPID

Abstract

Disturbances modify the responses of ecological processes, resulting in changes in the structure and composition of communities. The recurrence of these events over time defines regimes to which ecosystems tend to be adapted. However, climate change and anthropogenic actions have intensified changes in disturbance regimes, mainly in their frequency and seasonality. As a result, historically observed patterns become less frequent, giving rise to regimes to which many ecosystems are not adapted (novel disturbance regimes). New regimes can profoundly reorganize communities by altering composition, stability, and dominance, even when immediate species loss is not evident. The objective of this project is to understand how diversity under contrasting disturbance regimes varies at multiple scales. To this end, the proposal integrates four complementary chapters. The first focuses on changes in the variation of intra- and interspecific attributes. The second focuses on how assembly rules change when regime changes interact with climate variability. The third chapter focuses on quantifying how contrasting regimes affect the temporal stability of populations and communities, exploring the role of asynchrony and the relationship between local and regional scales. Finally, we will investigate how dominance patterns reorganize themselves along regime gradients and how this connects to community structure and dynamics. The project combines the use of time series with sampling of functional attributes and global databases. This integration allows responses at different levels of organization to be compared and helps us understand whether changes in metrics follow consistent patterns under contrasting regimes. Ultimately, the work contributes to our understanding of how new disturbance regimes can reorganize ecosystem diversity. (AU)