Efeitos da perda de habitat sobre as funções ecológicas de plantas lenhosas da Mata Atlântica

Abstract

Habitat loss is the main cause of the continued loss of biodiversity worldwide. Fundamentally, it is increasingly clear that losses in forest cover at landscape scales result in substantial changes in a series of ecological processes and ecosystem functions that ultimately determine the future trajectory of many of the most diverse and threatened forests in the world. The objective of this study is to evaluate the response of the taxonomic richness and functional diversity of woody plants to habitat loss at the landscape scale in the Brazilian Atlantic Forest. This study was carried out in eleven landscapes of 6 x 6 km (36 km2) with different proportions of forest cover (between 5% and 60%) in the Atlantic Forest of Bahia. Eight plots of 250 m2 were established randomly chosen in each landscape, and branches of all woody individuals with a circumference above the chest (CAP) equal to or greater than 8 cm were sampled. The classification of species by functional characteristic was based on books, dissertations, theses, scientific articles and virtual ecological database. The reduction of forest cover on the landscape scale negatively influences taxonomic and functional richness, and these relationships were non-linear. Functional uniformity was not influenced by the amount of forest in the landscape. Functional divergence was positively influenced by the reduction of forest cover in the landscape. The functional characteristics showed different responses to the amount of forest in the landscape. The functional characteristics associated with climatic plants were strongly and negatively influenced by the loss of forest cover. In contrast, the functional characteristics associated with generalist plants stood out in less forested landscapes. However, we emphasize that even the least forested landscapes still hold a significant part of the woody flora of the Atlantic Forest and can be important sources of carbon sequestration and should be considered in the management policies of the biodiversity of the Atlantic Forest.