浑太河流域鱼类生物完整性指数构建与应用

为了解决在不同区域和不同河流类型间等大尺度范围内F-IBI(鱼类生物完整性指数)评价方法体系的建立问题,以浑河-太子河(下称浑太河)流域为研究区域,构建符合区域性特征的生物完整性评价体系并进行应用研究. 于2014年5月对浑太河流域32个采样点的鱼类进行采样调查,根据鱼类群落特征的空间差异和浑太河流域水生态分区,将采样点分为中上游和下游区域两种类型. 通过综合栖息地和水质的标准化方法确定参照点和受损点,依据候选指标分布范围检验、敏感性分析和相关性检验,筛选出浑太河流域中上游F-IBI核心指标包括总物种数、Shannon-Wiener多样性指数、鲤形目鱼类物种数百分比、雅罗鱼亚科个体数百分比、鳅科鱼类物种数百分比、鲈形目鱼类物种数百分比、杂食性鱼类物种数百分比、肉食性鱼类物种数百分比、敏感性鱼类个体数百分比等9个指标；下游筛选出F-IBI核心指标包括总物种数、Shannon-Wiener多样性指数、鮈亚科鱼类物种数百分比、鲈形目鱼类物种数百分比、虾虎鱼科鱼类物种数百分比、中上层鱼类物种数百分比、东北特有鱼类物种数百分比、无脊椎动物食性鱼类物种数百分比、耐受性鱼类个体数百分比等9个指标. 分别提出了浑太河流域中上游和下游的参数标准化公式和健康评价标准,依此将浑太河流域健康状态划分为极好、好、一般、差和极差5个健康等级. 评价结果表明,浑太河流域健康状况整体偏差,在32个采样点中,健康状况处于差和极差的采样点占采样点总数的37.5%,一般的采样点占21.88%,仅有6.25%的采样点处于极好状态. Pearson相关性分析结果显示,F-IBI分值与电导率、ρ(BOD₅)、ρ(COD_Cr)、ρ(NH₃-N)和ρ(TN)均呈显著负相关,而与栖息地综合指数呈显著正相关,表明F-IBI可有效评估浑太河流域的健康状况. 

Development and Application of a Fish-Based Index of Biological Integrity for the Hun-Tai River Basin

Biological integrity has been widely used recently in river health assessment. The selection of the reference condition and the impacted condition are the most critical components in the process of developing an index of biological integrity. Meanwhile, the index of biological integrity is highly correlated with river type or eco-region in the watershed. For the purpose of developing a fish index of biological integrity (F-IBI), 32 sampling sites in the Hun-Tai River were sampled during the spring-summer period in 2014. Considering the natural variation of fish communities from upstream to downstream, 32 sample sites were classified into two types:the upper-middle streams and rivers according to species composition of fish assemblages and local fresh water eco-region delineation studies. All the reference sites and impaired sites were carefully selected based on standardized criteria, considering water quality and habitat quality. The results showed that the core indicators of F-IBI varied between upper-middle streams and rivers. Species richness, Shannon-Wiener's diversity index, species percentile of Cypriniforms, Leuciscinae, Cobitidae, Perciformes and omnivores, individuals percentile of Leuciscinae and intolerant species were selected as the core indicators in the upper-middle streams. Species richness, Shannon-Wiener's diversity index, species percentile of Gobioninae, Perciformes, Gobiidae, species inhabiting the surface layer, northeast China endemic fish, and invertivores, individuals percentile of tolerant species were selected as the core indicators in the rivers. Five categories of river health condition including excellent, good, fair, poor and very poor were used in the present study. The biological integrity results showed that the Hun-Tai river was generally degraded. 37.5% of sampling sites were under poor or very poor conditions, 21.88% of sampling sites were under fair conditions, and only 6.25% of sampling sites were under “excellent” conditions. Pearson's correlation analysis showed that our F-IBI is a useful and reliable index in the Hun-Tai River. F-IBI was significantly negative correlated with ρ(BOD₅), ρ(COD_Cr), ρ(NH₃-N), ρ(TN), and significantly positively correlated with the integrated habitat assessment index (IHAI).