关键词: 鄂西, 生态旅游区, 大型底栖动物, 群落结构, 生物评价指数

Abstract: The western Hubei province is a national water source protection zone and important ecotourism areas. To understand ecological health status of river ecosystem, a field survey on the macrozoobenthic community structure and water quality bioassessment was carried out in Juanqiao river (J), Lichuan reach of Qingjiang river (Q), Huangbo river (H) and Yunxi reach of Tianhe (T) from October 2014 to January 2017. A total of 61 families were observed in four rivers, including 5 phyla, 8 classes, and 18 orders. Leptophlebiidae, Atyoidae and subfamily Chironominae are the dominant group in J1, J2 and J3 sites, respectively. Heptageniidae accounts for 55.0% of total abundance caught in Q1, and Corbiculidae for 83.8% and 64.8% in Q2 and Q3, respectively; Viviparidae is the most dominated group in Q4 while strong tolerance Tubifex occurred. Tubifex and subfamily Chironominae account for 49.5% in Q5. Tolerance sensibility along water flow direction was decreased in J, Q and T rivers, indicating water quality degradation. However, all seven sampling sites were dominated by the sensibility macrozoobenthic group in H River, indicating a good water quality. The analysis of environmental variance with the principal components analysis showed the first axis could represent pollution gradient with 65.1% explanation．The linear regression analysis results further revealed a significant relationship between FBI and SIGNAL indices and the first axis. The correlations between both indices were significant which showed consistent results in river health assessment. The results indicate FBI and SIGNAL index are suitable for river health assessment in Western Hubei Province.

Key words: Western Hubei Province, ecotourism areas, macroinvertebrate, community structure, bioassessment index