Morfologia de folhas de Psychotria vellosiana (BENTH) sob influnência de borda e matriz em fragmentos florestais

Abstract

With the process of forest fragmentation appear environments with different environmental and microclimatic characteristics within the habitat. The edge, most of time, has high temperature, low relative humidity and soil and stronger winds compared with the environment of the forest interior. These changes may cause the reduction or even extinction of plant species. The remaining forests are often surrounded by different types of land use (matrix) that can influence the quality and intensity of edge effects in fragments. The objectives were to assesses whether (i) there would be differences in the microclimate between edge and interior within each fragment, (ii) the morphological and anatomical Psychotria vellosiana be influenced by microclimatic conditions within each fragment, (iii) different types matrices could interfere differently in the anatomical characteristics and morphology of P. vellosiana. The study was conducted in three forest fragment s located in southern Minas Gerais. There were no differences in relation to microclimatic conditions between edge and interior of edge fragment within and between the fragments. The leaves of P. vellosiana had the same leaf area and the same ratio of chlorophyll a/b to edge and interior in three fragments, not showing major anatomical plasticity for most characters. To check the influence of different matrices (pasture and sugar cane) were studied two of these fragments. Some anatomical data suggest a better adaptation of P. vellosiana in fragment surrounded by a matrix of pasture.