Influência da perturbação ambiental na assembleia de pequenos mamíferos nãovoadores na Amazônia Oriental

Abstract

Anthropogenic environmental disturbance results in different structural modifications of the forest, which can lead to changes in species composition patterns, taxonomic and functional diversity. We evaluated the influence of environmental disturbance on the structure and diversity of assemblies of non-flying small mammals in the eastern Amazon. We analyzed species composition, richness and abundance and their functional characters as assemblage descriptors, considering their environmental variations, in three levels of environmental disturbance: (i) forest interior; (ii) edge of the forest; and (iii) rural space. The diversity α (taxonomic and functional) remained relatively constant through the levels of anthropogenic environmental disturbance. However, in the taxonomic diversity β, the assemblage of the forest-edge community presents abundance gradients, where they share most of their species, but some individuals of the edge are lost in the forest. On the other hand, the rural forest and rural edge assemblages present a balanced variation of abundance, in which individuals of some species of forest and border areas are replaced by individuals of different species in rural space. Among the morphological attributes we observed subtler responses of the community, small mammals characterized by a larger tail predominate in forest areas and those characterized by a larger foot predominate in rural areas. We conclude that the morphological attributes (tail and foot length) are determining factors in the assemblage composition patterns of the small non-flying mammals and their habitat selection in environments facing anthropic impacts. The changes and patterns identified in our study are of crucial importance for biodiversity management and conservation plans.