Coexistence mechanisms of three congeneric simpatric species in a tropical forest

Author(s)

Kelly Fernandes de Oliveira Ribeiro

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia
• Defense date: 2022-11-30

Examining board members

Flavio Antonio Maës dos Santos; Rita de Cássia Quitete Portela; Simone Aparecida Vieira; Laszlo Karoly Nagy

• Advisor: Valéria Forni Martins; Flavio Antonio Maës dos Santos

Abstract

Understanding the ecological processes that promote the coexistence of tree species in environments with high diversity such as tropical forests is a central theme in community ecology. In these environments, the main coexistence mechanisms are based on deterministic processes such as environmental filtering and intra- and interspecific competition. The aim of this study was to investigate especially the deterministic processes using recent approaches that assess the spatial structure of populations and the variation in functional strategies of three congeneric sympatric tree species in a tropical forest subject to seasonal flooding (Restinga Forest). In a 1 ha-plot, all individuals belonging to three Myrcia (Myrtaceae) species were marked and mapped. We also collected data on environmental variables and functional traits of adults of the species studied. We found that the species are filtered with different degrees to the same environmental patches subject to flooding within the plot, showing that environmental filtering is an important process driving the local spatial distribution of the species studied. We did not find evidence supporting direct competition between the Myrcia species, direct competition between each Myrcia species and heterospecifics, diffuse competition among the three Myrcia species, and the action of negative-density dependence in each of the Myrcia species. Tolerance to patches subject to flooding might be mediated by the similar allometric coefficient of the three species studied, while the absence of competition among the Myrcia species might be explained by different functional traits related to resource acquisition (mainly leaf area, specific leaf area, and wood density). Thus, our conclusion is that the coexistence of the three Myrcia species is driven by niche differentiation as a result of selective pressures of past interspecific competition (AU)

• FAPESP's process: 16/21307-5 - Does niche differentiation allow the sympatric congeners species coexistence in a megadiverse forest?
• Grantee: Kelly Fernandes de Oliveira Ribeiro
• Support Opportunities: Scholarships in Brazil - Doctorate