Diversidade de comunidades de macroinvertebrados bentônicos em córregos de áreas preservadas do Triângulo Mineiro (MG) e Meia Ponte (GO)

Abstract

The study of diversity patterns of benthic macroinvertebrates communities in preserved areas is essential for the establishment of ecological reference areas, targeting the development of environmental quality diagnostics and proposals of monitoring in aquatic ecossistems in a local and regional scale. The present work investigated the composition of benthic macroinvertebrates communities on streams in preserved areas of Cerrado, four located at Triângulo Mineiro region and one at the microrregion Meia Ponte, southeast of Brazil. Samples of each available substrate type were collected from five sampling sectors, on each stream. The sorted aquatic insects were identified using stereomicroscopes and a dichotomous key. The values for abundance of individuals, taxa richness, EPT proportion, Chironomidae proportion, Shannon-Weaver Index (H’), Simpson’s Index (1-D) and Pielou’s Evenness Index (J) were calculated. The metrics were compared through analysis of variance (ANOVA one-way). To assess the quality of the sampled aquatic ecossistems, an adapted version of the BMWP index (Biological Monitoring Working Party) was applied. Individuals of 49 aquatic insects were identified, with a representative occurence of EPT families (which are less tolerant to disturbed environments). The streams Marimbondo, Panga Affluent and PESCAN, with high diversity and taxa richness, are shown as possible locations for the establishment of reference areas for biodiversity and biomonitoring studies. It is necessary to investigate the upstream conditions of the stream Água Fria, which was disturbed by anthropic pressures.