关键词: 逊别拉河, 底栖动物, 群落结构, 生物监测, 水质

Abstract: An investigation was conducted on the community structure ofmacrobenthos in the Xunbiela River from September to Oc- tober in 2011, and the water quality was assessed with biotic indices. A total of 55 species of macrobenthos were collected, belonging to 15 orders and 28 families, with 37 species of aquatic insects （67.27% of the total） belonging to 16 families and 7 orders. Pentaneura sp., Radix lagotis and Polypylis hemisphaerula） were of the first three species in incidence order. The macrobenthos were found at an average density of 64.80 ind·m^-2 and at a biomass of 4.43 g·m^-2. The predators including 23 species were predominately found in all fimctional feeding groups, the others including 15 shredders, 11 collectors and 6 scrapers. The BI assessment revealed that the water quality in Xunbiela River was clearer.

Key words: Xunbiela River, macrobenthos, community structure, biomonitoring, water quality