B21L-01
Biodiversity and functional regeneration during secondary succession in a tropical dry forest: from microorganisms to mammals
Tuesday, 15 December 2015: 08:00
2010 (Moscone West)
Mário Marcos do Espírito Santo1, Frederico S Neves2, Henrique M Valério1, Lemuel O Leite1, Luiz A Falcão2, Magno Borges1, Marina Beirão2, Ronaldo Reis Jr.1, Ricardo Berbara3, Yule R Nunes1, Alex Silva1, Luciana F Silva1, Paulo R Siqueira1 and Rede Mata Secas, (1)Universidade Estadual de Montes Claros, Departamento de Biologia Geral, Montes Claros, Brazil, (2)Universidade Federal de MInas Gerais, Biologia Geral, Belo Horizonte, Brazil, (3)Universidade Federal Rural do Rio de Janeiro, Departamento de Solos, Rio de Janeiro, Brazil
Abstract:
In this study, we aimed to determine the changes on soil traits, forest structure and species richness and composition of multiple groups of organisms along secondary succession in a tropical dry forest (TDF) in southeastern Brazil. We defined three successional stages based in forest vertical and horizontal structure and age: early (18-25 years), intermediate (50-60 years) and late (no records of clearing). Five plots of 50 x 20 m were established per stage, and the following groups were sampled using specific techniques: rhizobacteria, mycorrhiza, trees and lianas, butterflies, ants, dung beetles, mosquitoes (Culicidae), birds and bats. We also determined soil chemical and physical characteristics and forest structure (tree height, density and basal area). Soil fertility increased along the successional gradient, and the same pattern was observed for all the forest structure variables. However, species richness and composition showed mixed results depending on the organism group. Three groups usually considered as good bioindicators of habitat quality did not differ in species richness and composition between stages: butterflies, ants and dung beetles. On the other hand, rizhobacteria and mycorrhiza differed both in species richness and composition between stages and may be more sensitive to changes in environmental conditions in TDFs. The other five groups differed either in species richness or composition between one or two pairs of successional stages. Although changes in abiotic conditions and forest structure match the predictions of classical successional models, the response of each group of organism is idiosyncratic in terms of diversity and ecological function, as a consequence of specific resource requirements and life-history traits. In general, diversity increased and functional groups changed mostly from early to intermediate-late stages, strengthening the importance of secondary forests to the maintenance of ecosystem integrity of TDFs.
