主成分分析法在三江交汇处水质分析中的应用

Analyzing Water Quality of Converge Region of three Rivers Using Principle Component Analysis

本文应用主成分分析法,利用三江交汇处的三个断面从1984年到1998年的监测资料对交汇处的水质做分析,分析前先对量化数据标准化处理,处理后提取主成分,并且计算其贡献率和累计贡献率,再由相应的特征向量得到主成分的线性表达式。结果表明:五项影响因素中,三个断面枯水期均受亚硝酸盐氮的影响比较大,丰水期和平水期均受悬浮物和化学需氧量的影响比较大。交汇前,小南门断面的水质综合污染最严重,凉姜沟断面的水质综合污染最轻;交汇后,三江口断面的水质在两者的缓冲下,水质综合污染居中。则说明主成分分析法为河流的综合治理提供了科学依据。

This paper analyzes the data of water quality monitored from 1984 to 1998 at converge region of three rivers using principle component analysis. Before analysis, the physicochemical properties are processed according to standardization, and then calculate the devotion and accumulative devotion of the principle components. Afterward, linear expressions are got from corresponding eigenvectors. The result shows ： at all of the three sections, among five influencing factors, NO2-N has significant influence in low water period, but suspending solids and COD have significant influence in abundant and plane water periods. Before converge, water quality at of Xiaonamnen section is the worst, but water quality at Liangjianggou section is the best of all. After converge, water quality at Sanjiangkou section is placed in the middle because of buffer action of the above two sections. It shows that principle component analysis provides a scientific way for comprehensive treatment of rivers.