武水河水质时空分布特征及污染成因的解析

运用主成分分析和聚类分析方法,对2013—2015年武水河流域7个监测断面的11个水质指标数据进行分析,揭示武水河水质时空分布差异性,辨识主要污染因子,解析污染成因.2013—2015年,流域水质整体较好,尚存在不达标断面.长河水库和黄岑水库出现NH_3-N超标现象,岑水桥和芙安河老桥断面出现重金属As超标现象,但NH_3-N和As浓度趋于降低.武水河流域监测断面水质由高到低的顺序为:水库断面支流断面干流断面.2013年,流域主要污染因子为NH_3-N、TN和As,主要源自农业面源污染和工业污染;2014年,流域主要污染因子为COD_(Mn)、NH_3-N、TP,主要源于生活污水和工业污染;2015年,流域主要污染因子为BOD_5、粪大肠杆菌、pH,主要来源生活污水和畜禽养殖.因此,流域内工业污染和农业面源污染对水质的影响逐年降低,生活污水和畜禽养殖对水质的影响逐年增大.流域内通过建设污水处理厂,实施重金属综合治理等项目,减少污染物排放,改善流域水环境质量.

Spatio-temporal distribution of water quality and source identification of pollution in Wushui River Basin

Principal Component Analysis (PCA)and Cluster Analysis(CA) were applied for 11 water quality indices of seven monitoring sections in Wushui River Basin from 2013 to 2015 to analyze the spatio-temporal distribution of water quality, seek the main pollution factors and identify the causes of pollution. The water quality was good in the basin, but the non-compliance section still existed. NH₃-N was monitored exceeding the standard in Changhe and Huangcen reservoirs, as well as As in Censhuiqiao and Fu''anhelaoqiao. However the concentrations of NH₃-N and As tends to decrease. The water quality is in decreasing order of reservoir sections > tributary sections > mainstream sections. NH₃-N, TN and As are sought as the main pollution factors in 2013, which are mainly derived from agricultural non-point source pollution and industrial pollution. COD_Mn, NH₃-N and TP are proved as the main pollution factors in 2014, mainly from domestic sewage and industrial pollution. BOD₅, Escherichia coli and pH were the main pollution factors, attributed to domestic sewage and livestock breeding. Therefore, the contributions of industrial and non-point source pollutions deterioriate the water quality year by year, but the contributions of domestic sewage and livestock breeding were increasing. During "13th Five-Year" period, sewage treatment plants need to be constructed, and heavy metal treatment projects should be planned to improve water quality in Wushui River Basin.