基于PCA的巢湖抱书河污染源解析研究

The Research of the Source Apportionment of Baoshu River in Chaohu City Based on PCA

针对巢湖抱书河流域16个监测断面的COD、NH_3-N、TP,利用单因子指数法和综合污染指数法进行了枯水期、平水期和丰水期的水质评价。结果表明,枯水期COD超地表V类水标准断面占比为50%,NH_3-N为75%,TP为25%,平水期分别为100%、75%、100%,丰水期为81.25%、62.5%、75%,总体水质属于Ⅴ类和劣Ⅴ类水;综合污染指数评价结果,枯水期监测断面轻度污染占比6.25%、中度污染占比43.75%、重度污染占比43.75%、严重污染占比6.25%,平水期重度污染占比43.75%、严重污染占比56.25%,丰水期重度污染占比31.25%、严重污染占比68.75%,枯水期水质略优于平水期和丰水期;对NH_3-N、TP、COD、pH、DO、浊度、电导率指标进行了主成分分析,结果显示,氮磷为水质恶化的主要污染源。

The COD, NH3-N and TP of 16 monitoring sections in Baoshu River Basin of Chaohu city were evaluated by single factor index method and comprehensive pollution index method in the low flow period, normal flow period and high flow period. The results showed that the proportion of COD exceeding the surface V standard section in the low flow period was 50%, NH3-N was 75%, TP was 25%, the proportion of COD was 100%, NH3-N was 75%, TP was 100% in the normal flow period, the proportion of COD was 81.25%, NH3-N was 62.5% and TP was 75% in the high flow period, respectively. The water quality belongs to class V and inferior class V water. The results of compre hensive pollution index evaluation showed that the ratio of the minor pollution in the monitoring section was 6.25%, the moderate pollution was 43.75%, and the severe pollution was 43.75% in the low flow period. The ratio of the mon itoring section of the serious pollution was 6.25%, and the severe pollution was 43.75% in the normal flow period. The ratio of the monitoring section of the serious pollution was 56.25%, the severe pollution was 31.25%, and the se rious pollution was 68.75% in the high flow period. The water quality in the low flow period was slightly better than that in normal flow period. The main components of NH3-N, TP, COD, pH, DO and conductivity were analyzed. The results showed that nitrogen and phosphorus were the main pollution sources.