Study about constructing biological integrated biotic index of (B-IBI) is a hot topic in the river health assessment and river restoration management. Macroinvertebrates communities were sampled at 23 sampling sites of Yongding River Basin in the April, 2017. For the study purpose of constructing the B-IBI in the Yongding River,the other extra 5 sampling sites were selected as reference sites in the Chaobai River based on the water quality and habitat quality, where presented the minimum human disturbances and similar community composition with the study regions. A total of 33 candidate biological index of macroinvertebrates were referred. By using the analyses of distribution ranges,variation between the references sites and impacted sites,and inter-correlation,totally 6 core indices were used for the construction of B-IBI. B-IBI was composed of the total number of taxa,relative abundance of the most dominate taxa,relative abundance of Chironomidae,percentage of EPT taxa,taxa richness of sensitiveness,and the Family Biotic Index(FBI).The B-IBI scores were calculated by using two classic methods, three scoring method and the ratio scoring method. The results showed that two methods were highly correlated (R>0.90). Both methods were all quite high in discriminability between the references sites and impacted sites by using discriminating power analysis. Therefore,the commonly used ratio scoring method was selected for use to establish health evaluation criteria suitable for the Yongding River. Assessing with those criteria,the results show that 16 sites were poor and 7 sites were fair in the Yongding River. The average values of B-IBI scores were 1.97, 1.86, and 1.78 at the Yanghe River, the Sanggan River and the main stream of Yongding River,respectively. The average score was 2.48 at the Guishui River. B-IBI scores were significant correlated with habitat quality and DO positively, and significant correlated with ammonia nitrogen, turbidity and conductivity negatively. This study identified the loss of B-IBI significantly, and the construction and function of macroinvertebrate communities showed a trend of overall degradation in the Yongding River. Identifying and decreasing the key human disturbances would be urgent to protect and restore the structure and function of the river ecosystem in the Yongding River.%构建大型底栖动物生物完整性指数是河流健康评价与河流修复的重要步骤.根据2017年4月永定河流域23个采样点的大型底栖动物生物监测数据,基于监测点水质状况与栖息地质量综合评估指数得分,选择潮白河水系大型底栖动物类群相似且人为干扰较小的5个监测点作为参照区域,构建永定河B-IBI(大型底栖动物生物完整性指数).通过对大型底栖动物33个生物参数的分布范围检验、判别能力分析和Spearman相关性检验,最终确定永定河B-IBI由总分类单元数、蜉蝣目(E)-襀翅目(P)-毛翅目(T)个体相对丰度、优势分类单元个体相对丰度、摇蚊科个体相对丰度、敏感类群分类单元数、科级耐污指数(family biotic index,FBI值)等6个核心参数构成.采用生物完整性研究中常用的比值法和三分法构建的B-IBI评价得分体系.结果表明,两种方法计算出的B-IBI均具有较高的判别能力,均能较好地判别参照水体和受损水体的健康状况,二者具有较高的相关性和一致性(R>0.90).永定河河流健康评价结果表明,洋河、桑干河和永定河干流监测点B-IBI平均得分分别为1.97、1.86和1.78,妫水河B-IBI平均值为2.48,23个采样点中有16个处于较差状态,7个处于一般状态.相关性分析表明,B-IBI指数与栖息地质量综合评估指数得分、ρ(DO)呈显著正相关,与ρ(NH4+)、浊度、电导率呈显著负相关,表明B-IBI指数对于栖息地人为干扰和水质污染均具有较强的指示作用.研究显示,永定河大型底栖动物生物完整性基本丧失,全流域底栖动物群落呈现全面退化趋势,识别影响大型底栖动物群落的关键要素、恢复永定河河流生态系统结构和功能研究亟待开展.
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