This study aimed to know the community of benthic insects in 17 streams in northeastern Pará, Eastern Amazonia under different land uses and investigate the variations in the abundance, richness and diversity of aquatic insect community to vegetation cover the immediate surrounding area (riparian zone) and landscape (slopes of the watershed where it enters the stream sampled). The benthic macroinvertebrates were collected between July and October 2010, the period of lowest rainfall. At each point were made to 10 Surber samples for quantitative analysis and three hand-net only qualitative character. To evaluate differences between the richness, EPT abundance and diversity, we used an ANOVA and cluster analysis to summarize the biotic data. For differences in the scales of study were then used an ANOSIM and routine SIMPER. Environmental characteristics were also evaluated searching to correlate them to the taxonomic composition and distribution of taxa by Canonical Correspondence Analysis (CCA). A total of 46,371 individuals were collected, in which 11,384 with Surber, distributed in 61 taxa with a predominance of aquatic insects. The highest abundances were observed Chironomidae, Ephemeroptera, Trichoptera and Coleoptera. Abundance, richness and EPT were greater in sections of streams to riparian vegetation and watershed predominantly of igapó anthropic forest (references). The environmental variables of greatest influence on the community were percentage of forest environment in the riparian zone, average water temperature, turbidity, percentage of coarse and fine litter, pH, flow channel and coefficient of variation of channel width. The results showed differences in community composition in relation to different land uses. Through the ecological descriptors, it was detected that the watershed with the highest percentage of anthropic forest area and successional and higher percentage of riparian vegetation surrounding (30m) showed better environmental conditions than those dominated pastures.
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