汉江流域硫铁矿区厚子河支流水质评价研究

Research on water quality evaluation of the Houzi River in the pyrite mining area of the Hanjiang River Basin

为查明厚子河不同区域河水受硫铁矿污染的程度,在厚子河支流4个典型河流断面采集水样,开展水质全分析测试,并采用单因子评价法和综合水质标识指数法进行评价分析。研究结果表明:(1)运用单因子评价法对硫铁矿区厚子河水质评价的结果无差异,均为劣Ⅴ类水;而运用综合水质标识指数法的评价结果显示,距离硫铁矿开采区由近及远的4个断面HZ001、HZ002、HZ003、HZ004的综合水质标识指数逐渐下降,水质类别分别为劣Ⅴ类且黑臭、劣Ⅴ类但不黑臭、Ⅳ类、Ⅲ类,符合现场调查的实际情况,能够反映距离污染源越远时河水水质趋好的总体态势;(2)综合水质标识指数法不仅可以客观反映同一河流各个断面所处的综合水质类别、同一水质类别中受污染的不同程度以及与水环境功能区类别的比较结果,而且能够实现对劣V类水质污染程度的精细划分,相较于单因子评价法更加客观、科学、全面,适用于矿山开采等重污染区域河流断面水质污染情况的研判。

In order to find out the water pollution extent in different areas of Houzi River, water samples were collected from four typical river sections of the tributary, and water quality analysis was carried out. The single factor evaluation method and the comprehensive water quality index method were used for evaluation and analysis. The results show,(1) the results of water quality evaluation of Houzi River in the pyrite mine area based on the single factor evaluation method are all inferior V class water with no difference. Nevertheless, the comprehensive water quality index method is used to evaluate the water quality of Houzi River in the four sections HZ001, HZ002, HZ003 and HZ004, from near to far of the pyrite mining area, and the comprehensive water quality index is gradually decreasing. And the corresponding categories are inferior V with black odor, inferior V but without black odor, class IV, class III respectively. All these results are in line with the actual situation based on the site investigation, which can really reflect that the water quality is becoming better with the increasing distance from the source of pollution.(2) The comprehensive water quality index method can objectively reflect the comprehensive water quality category of each section in the same river, the different pollution levels in the same water quality category, and the comparison with the water environment functional area category. And this method can also achieve the fine division of the pollution degree of inferior V water quality, which is more objective, scientific and comprehensive than the single factor evaluation method. So, the comprehensive water quality index method is suitable for the study of water pollution of different river sections in heavily polluted areas such as mining areas.