运用典范对应分析（Canonical Correspondence Analysis, CCA）研究了12项水质指标对北江流域大型底栖动物分布的影响. 结果表明，物种与水质因子的相关性在95%以上，说明大型底栖动物在北江的分布与水质因子有密切的联系. 温度、pH值、电导率、化学需氧量和硅酸盐是影响北江大型底栖动物物种分布的主导因子，氯化物、氨氮和总氮对其分布也有重要影响. 本研究共采集大型底栖动物46种，各类底栖动物对于生态环境的需求不同，在各水质因子的维度上呈现出生态分化现象. 北江以底栖动物为指示可以依次划分为污染物含量低，水质较好的绥江中下游地区；水质受到有机污染的干流；以及水质一般，尚未受到污染影响的北江上游各一级支流.
The relationship between macrobenthos and 12 water quality factors in Beijiang River Basin was studied by Canonical Correspondence Analysis (CCA). The species-environment correlation was higher than 95%, which indicated the distribution of macrobenthos in Beijiang River Basin was strongly affected by water quality factors. Temperature, pH, conductivity, COD and SiO3-Si were the five major factors affecting the macrobenthos ecological distribution. Cl-, NH4-N and TN were also influential on the distribution of the macrobenthos to some extent. A total of 46 macrobenthos species were collected during the research period. Different species adapted to different ecological environment, and every kind of species had strong correlations with distinctive water quality factors. Indicated by macro-invertebrates, water quality was different from river to river in Beijiang River Basin. The water quality in midstream and downstream of Suijiang is good and little pollutants can be found. Water in mainstream of Beijiang had been contaminated by organic pollutants. And other tributaries located in upstream of Beijiang hadnt been affected significantly by pollutants.