大型底栖动物完整性指数在漳河上游水生态评价中的应用

Application of benthic index of biotic integrity for aquatic ecological assessment in the upper reaches of Zhanghe River

为了解漳河上游水生态健康状况,于2015年非汛期和汛期对漳河上游的大型底栖动物时空分布状况进行调查。根据所调查站点的水质和人为扰动情况,将布设的12个站点分为参照点(4个)和受损点(8个)。使用大型底栖动物完整性指数对漳河上游水生态状况进行评价,对4个类型的18个候选生物参数的分布范围、判别能力以及相关性等进行分析,筛选出构建漳河上游大型底栖动物完整性指数的4个核心参数,分别为总分类单元数、(甲壳类+软体类)单元百分比、耐污分类单元数百分比和捕食者百分比。采用比值法统一量纲,获得漳河上游12个站点的B-IBI值。结果表明,漳河上游的12个站点中,5个站点为健康或亚健康状态,3个站点为一般状态,4个站点为较差或病态。

In order to evaluate the ecological health condintion of the upper reaches of Zhanghe River, an adapted benthic index of biotic integrity (B-IBI) was developed in 2015. Macro-invertebrates were sampled at 12 monitoring stations which were grouped into two condition categories (reference and impaired stations) according to the level of degradation. A total of 47 benthic macroinvertebrates taxa were identified, including aquatic insects 33 taxa (including Chironomidae 16), Mallusca 8, Annalida 3 and Crustacea 3 taxa. Aquatic ecosystem healthy assessment was researched using Benthic Index of Biotic Integrity (B-IBI). Eighteen candidate biological metrics in 4 categories based on macro-invertebrate assemblages were chosen, and value distribution, discriminatory power and pearson correlation were analysed. Meanwhile, total taxa and percentages of (Crustacea + Mollusca)%, tolerant taxa % and predators % were screened out to form a B-IBI index system for the upper reaches of Zhanghe River. Assessment results using B-IBI showed that in the whole watershed, 5 of sampling stations were in "healthy" and "sub-healthy" state, 3 were in "fair" state, and 4 were in "poor" or "very poor" state. Discussion about the ecological condition and B-IBI evalution results of the whole watershed was conducted.