水污染综合指数评价及主导因子分析——基于湖北某水库的水环境空间分布特征

Evaluation of water pollution comprehensive index and analysis of its dominant factor——Based on water environment spatial distribution characteristic of a reservoir in Hubei

为了探究河流型水库水质的主要污染指标,文章通过湖北省某河流型水库2018~2019年的水样测定结果,以水库水质空间分布特征为基础,采用了污染综合指数法及主成分分析对水质进行了评估。结果表明:该水库主要受氮磷污染,主要归因于周边农业生产污水的随意排放,以及库区内水生植物的腐烂分解。同时,主成分分析也明确了主要水质指标之间的影响关系:第一主成分中正负荷因子为水温和高锰酸盐指数,主要反映了水温上升对有机物含量增加有促进作用;第二主成分中正负荷因子总氮、硝酸盐氮指标与负荷因子pH则反映了水库中水生植物生长消耗氮盐从而使pH升高的现象;第三主成分的正负荷因子为磷酸盐指标,体现了该水库水体的富营养化程度。

In order to analyze the main pollution index of riverine reservoir,the comprehensive indexes and principal component analysis were used to evaluate the water quality of this reservoir,according to the spatial distribution characteristics of water quality through the measurement results of a riverine reservoir in Hubei Province during 2018-2019.The result showed that this reservoir was mainly polluted by nitrogen and phosphorus.The main reason was the indiscriminate discharged of sewage from surrounding agricultural production and the decomposition of aquatic plants in the reservoir.In addition,the influence relationship among the indexes was also clarified.The positive load factors were water temperature(T)and permanganate index(CODMN)of the first principal components,which mainly reflected that the rise of water temperature promoted the increase of organic matter content.While the second principal component positive load factors were total nitrogen(TN)and nitrate nitrogen(NO;-N),and the negative load factor was pH,which reflected the phenomenon of aquatic plants in the reservoir consumed nitrogen salt,thus increasing pH.The positive load factor of the third principal component was phosphate(PO;)index.It indicated the eutrophic degree of the water in this reservoir.