Distribuição espacial de coleópteros aquáticos em poças temporárias ripárias em uma floresta de terra firme na Amazônia central

Abstract

Temporary ponds are aquatic habitats that pass periodically a dry phase. They are inhabitated for several taxa, especially water beetles. Studies show that environmental factors and variations in physicochemical characteristics of water can influence the distribution of organisms that use temporary ponds. In this study, the effect of habitat structural features (number of ponds, stream width, floodplain area, canopy cover) and physicochemical characteristics (pond area, vegetation area, distance of pond from stream, hydroperiod, pH, conductivity) were evaluated in relation to the number of species of water beetles and abundance of Cybister sp., Hydaticus sp., Hydrobiomorpha sp., Tropisternus sp. and Helochares sp. The effects of drainage basin were evaluated in species number. The number of species (P=0,033, R2= 0,323) and abundance of Cybister sp. (P= 0,039), Hydaticus sp. (P= 0,017), Hydrobiomorpha sp. (P= 0,046) and Helochares sp. (P= 0,041), were positively related to floodplain area. There was a significant difference in number of species between the drainage basis (F1,26= 25,345, P< 0,001). The abundance of Hydrobiomorpha sp. (P= 0,018) and Hydaticus sp. was positively related to conductivity (P= 0,001, R2= 0,565). The abundance of Hydaticus sp. was negatively related with the pH (P= 0,005, R2= 0,056). In view of the lack of studies in riparian temporary ponds in Tropical Forest, the results are compared with the studies of permanent or temporary puddles of Temperate zones, which are quite different both in structure and in variations of the physicochemical characteristics of water. The data presented show that the species of water beetles in Reserva Florestal Adolpho Ducke, are affected by environmental factors and evidential differ between drainy basis in RFAD. Moreover, the biological differences among groups show that the environment structure and the physicochemical conditions exercise a key role in the spatial distribution of these organisms, highlighting the importance of this study in the initiatives for the conservation and management of species of temporary environments in the Tropical region.