不同地下水水质评价方法的对比研究——以宜良县为例

COMPARATIVE ANALYSIS OF THE EVALUATION METHODS FOR GROUNDWATER QUALITY: A CASE STUDY OF YILIANG COUNTY

不同的水质评价方法有不同的适应性,为准确评测昆明市宜良县地下水水质,以2015年宜良县10个主要监测井的监测数据为基础,选取硫酸盐、硝酸盐氮等6个水质评价因子,分别采用传统、改进内梅罗污染指数法、加附注评分法和主成分分析法进行水质评价。研究结果表明:传统内梅罗指数法评价效果较差;改进内梅罗指数法仅适用于掌握水体的污染程度;主成分分析法适用评价指标过多的情况,通过降维对其简化,最大限度保留原始信息;加附注评分法在评价过程中将全部指标纳入模型计算,评价结果拟合度高、适应性、稳定性好,评价更为科学客观,最适合用于研究区地下水评价。

The applicability varied among different water quality evaluating methods. In order to make an accurate evaluation on the quality of groundwater in Yiliang County,data from 10 main monitor wells in Yiliang County in 2015 were selected as the grounding,from which six evaluating factors including sulphate and nitrate nitrogen were brought into the evaluation system by traditional/improved Nemero index method,plus-score noting method and principal component analysis method. Research results showed that it was unsatisfactory by using traditional Nemero index method; improved Nemero index method was only suitable to the test of of water pollution degree; principal component analysis method applied for situations where there were too many indexes,which could simplify the multiple indexes by reducing dimensions,thus maximizing the retained original information; one more scientific and objective assessment was plus-score noting method,by which all indexes could be calculated in the model during the process of analysis. This method might be more prone to reach a conclusion with high fitting degree and good adaptability and stability,so it was a good choice for regional groundwater assessment.