Assessing Groundwater Pollution Using Fuzzy Factor Analysis Method: A Case Study of Luoyang City in Henan Province
模糊因子分析在地下水污染评估中的应用——以河南省洛阳市为例

It is difficult for traditional methods to characterize quantitatively pollution contribution rate of different pollution sources to single sample point. Fuzzy factor analysis methods, fuzzy ISODATA cluster analysis (FICA) and factor analysis (FA) were utilized to assess the factors responsible for the hydrochemical composition of the groundwater. The new methods were employed in Luoyang City, where twenty-eight hydrochemical variables were considered in 241 samples collected. Four pollution sources were identified, i.e., anthropogenic activities, processing manufacturing industries, bedrock weathering, and energy enterprise/ancient vestige. The relative pollution contribution rates of the four pollution sources are 20.291% for anthropogenic activities emission, 14.324% for processing manufacturing industry emission, 5.831% for bedrock weathering source, and 4.392% for energy enterprise/ancient vestige source. Meanwhile, the pollution contribution rates of pollution sources to each sample point were also calculated. In regard to the groundwater pollution prevention of Luoyang City, the reduction of the domestic sewage emission and chemical fertilizer consumption and the relocation of industries with heavy pollution seem to be effective ways to control groundwater pollution; as for the sample point, concrete pollution prevention measures should be provided for different sample points according to their primary pollution sources. The fuzzy factor analysis method is proved to be a practical, simple and useful tool to assess and prevent groundwater pollution.