Edge effects on biomass of neotropical forests

Abstract

Deforestation is the main factor leading to biomass loss in tropical regions, but the effects of forest fragmentation on biomass stocks are poorly understood. Fragmentation acts on biomass through floristic and functional simplification of plant community on edge-affected areas. In this process of biotic homogenization, emergent, large-seeded, shade tolerant species are preferentially affected allowing the proliferation of small-seeded, softwood, pioneer species, which stocks few amount of biomass. Thus, biomass is affected negatively on edge areas. Fragmented and edge-affected landscapes are largely spread and rapidly increasing worldwide leading to high levels of carbon loss by forest degradation, especially tropical forests. Therefore, the main objective of this study is to determine the local drivers of biomass loss in Neotropical landscapes. Using collected data about plant community we will structure a database of biomass stocks in fragmented landscapes. With the database we will evaluate the effects of (1) distance to edge, (2) multiple edges, and (3) time since edge formation on biomass stocks and biomass by functional plant groups. For data analyses we will use Generalized Linear Models, an approach that have been increasingly used for analysis of ecological data, although poorly explored for spatial data. The results of this project would be an instrument to subsidize the carbon emission estimates by the determination of the dimension of biomass loss at Neotropical forests. (AU)