丹江口水库生态系统健康综合评价

Comprehensive Assessment of Danjiangkou Reservoir Ecosystem Health

2007年7月～2008年5月按季度对丹江口水库4个库区(丹江库区、汉江库区、取水口和五青入库区)的水环境和浮游生物进行了调查,采用生态系统健康指数(EHI)法和营养状态指数(TSI)法对该水库的生态系统健康状态进行定量的综合评价.结果表明:2007年7月～2008年5月,丹江口水库整体处于中营养状态,健康状态中等,健康状态总趋势是丹江库区>取水口>汉江库区>五青入库区;各库区生态系统健康状态存在季节性差异,丹江库区、取水口两库区全年为中等,汉江库区在夏季为较差,其它季节中等,五青入库区在冬季最差,其它季节较差.此外,对两种评价方法进行了比较,表明丹江口水库属于响应型生态系统,生态系统健康指数(EHI)适用于丹江口水库生态系统健康的评价.

Seasonal investigations on water environment and plankton were carried out from July 2007 to May 2008 in the four selected regions of Danjiangkou Reservoir （Regions Danjiang, Hanjiang, Qushuikou and Wuqing）. Ecosystem health index （EHI） and trophic state index （TSI） were used to assess the ecosystem health state of the reservoir. The results showed that, the health state of the whole reservoir was at medium eutrophication level during the study periods and displayed a decreasing trend spatially as follows： Danjiang, Qushuikou, Hanjiang and Wuqing regions. Besides, the health state of some regions displayed seasonal varitations： It was at medium eutrophication level in the regions of Danjiang and Qushuikou in the whole year; it became worse in Hanjiang region in summer, but medium in other seasons; the state of the Wuqing region was worst or worse in the whole year. Moreover, the comparison of assessment results from the two methods concluded that Danjiangkou Reservoir belonged to response ecosystems, and EHI method was suitable for the assessment of its ecosystem health state. Fig 6, Ref 34