基于鱼类生物完整性指数的广东鉴江流域环境质量评估

根据鉴江流域21个观测点鱼类调查所收集的数据,结合历史资料的记录,初步构建基于鱼类生物完整性评价的26个初选指标,并根据指标属性分类进行初筛,对10个通过的候选指标进行分布范围、判别能力和Pearson相关性分析,确定了由总的种类数占期望值的百分比、鲤科鱼类占总种类数的百分比、鳑鲏亚科鱼类占总种类数的百分比、耐受性强鱼类占总种类数的百分比和产漂流性卵鱼类占总种类数的百分比共5个主评指标组成的生物完整性指数体系,并用于鉴江流域部分河段的生态健康评价.结果表明,凌江鱼类完整性相对较好,罗江一般,平定水、袂花江和鉴江干流较差,小东江最差;鉴江流域大多数河段的综合健康状态处于较差状态,需要对鉴江流域进行生态修复以达到相对健康状态.评价结果与河流受人为干扰的实际情况相吻合,研究构建的评价体系可供周边地区使用和借鉴.

Environmental quality assessment of Jian River Basin(Guangdong) based on fish biotic integrity index

Based on the data collected from 21 sites in Jian River Basin and historical data, 26 candidate metrics representing attributes of fish assemblage were screened. Of which, tenmetrics passed the initial selection, then the analyses of index value distribution, discrimination ability and Pearson correlation were performed, finally 5 major indicators were used for the biotic integrity index system to assess the environmental quality of Jian River Basin, which are percent of total number of species in expectation, percent of cyprinid species,percent of Acheilognathinae species,percent of tolerant species, percent of species with pelagic eggs. It suggested that the fish-based biological integrity index was good in Ling River, fair in Luo River, poor in Pingding River, Meihua River and the main stream,and Xiaodong River was the worst. As comprehensive health status of rivers was in the worse state, certain measures should be taken for ecological restoration to the relatively healthy state. The assessments were consistent with the actual situation of human disturbance in this river drainage. The established fish biotic integrity index in this study could be used to assess environmental quality or used as reference for rivers in adjacent regions.