Efeito de borda sobre a assembléia de plantas herbáceas em um fragmento de floresta Atlântica, Alagoas, Brasil

• Autor(a) principal: LIMA, Liliane Ferreira
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRPE
• Texto Completo: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/4851
• topic: Efeito de borda; Assembléia de herbácea; Fragmento florestal; CIENCIAS BIOLOGICAS::BOTANICA

The set of microclimate modifications resulting from the drastic increase of the forests edges causes a series of biological alterations that modify the species composition and community structure, bringing serious risks to the biodiversity. With the intense forest fragmentation the edges are becoming increasingly abundant in regions around the world, in a way that the major part of the landscape is dominated by the edge effects. Thus, herbaceous plants constitute an important vegetal group of analysis of the edge effects, due to its close relationship with environmental factors, responding rapidly to anthropogenic alterations. So, the aim of this work was evaluate the edge effect on the herbaceous assembly in a fragment of Atlantic forest in the Northeast of Brazil. We sought to identify the variations in richness, diversity and individuals density, as well as temperature and soil moisture and the litter accumulation between the edge and the inte-rior of the fragment, analyzing if there is any relationship between species composition and those environmental variables. 50 plots of 5 x 5 m were sampled in each studied environment – edge and interior, where all individual were counted and it was obtained the species number for determination of richness, diversity, equability, absolute fre-quency and individuals density. Environmental parameters were collected inside each parcel. 137 species were identified: 75 in the edge, distributed in 54 genus and 27 fami-lies and 97 in the interior, distributed in 63 genus and 33 families. From overall species, 40 are exclusive from the edge and 62 from the interior of the fragment. 2806 individu-als were obtained in the interior and 4948 in the edge. Significant differences were ob-served in richness (U = 887.5; p = 0.0062) and diversity of species (p < 0.05; t = 16.54) and individuals density (t = 4.7255; p < 0.0001) between edge and interior. It was also observed the significant differences between the values of temperature (U= 299; p < 0,0001), soil moisture (U= 985; p= 0.0339) and litter accumulation (U=956.5; p= 0.0215) between the two studied habitats. These results show that the herbaceous as-sembly is being affected by the edge effects, forming a set of depleted species on forests edges, due to microclimate conditions of this area.