福建敖江流域水域生态系统健康评估

Evaluation of aquatic ecosystem health in Aojiang Basin,Fujian Province

以敖江流域为研究区,通过采集底栖动物、鱼类等样品,结合监测数据分析流域水域生态系统健康状况,并采用指标体系评估方法对水域生态系统进行评估.结果表明:敖江流域水质总体良好,但山仔水库总氮、总磷浓度长期超标,水体存在富营养化和藻类水华暴发生态环境问题;底栖动物种类呈现支流多于干流、河流多于水库的规律;鱼类种类上、中、下游各科物种组成差异不显著,鱼类区系特点具有较明显的热带、亚热带区系特点;流域上游、中游水域生态健康良好,下游水域生态健康一般.

According to the suvery on benthic animal and fish samples, and combining with monitoring data, we analyzed the health condition of aquatic ecosystem, and made evaluation with an index in Aojiang Basin. The results showed that the water qual- ity was generally good in Aojiang Basin, but total nitrogen and total phosphorus concentration of Shanzi Reservoir exceeded standard for a long term which led to ecological environment problems, such as eutrophication and algae outbreak. Species numbers of ben- thic animals presented in the tributaries were greater than that in the river, with smallest species number in reservoir. The fish com- position in the upstream, midstream and downstream was not of significant difference, exhibiting a tropical and subtropical floristic characteristics. The health condition of aquatic ecosystem in both upstream and midstream was good, while that in downstream was moderate.