统计学在填埋场地下水污染指标间相互关系及水质污染程度中的应用研究

为研究填埋场地下水中主要污染指标间相互关系及水质污染程度,基于北京市某填埋场220组地下水样本,对地下水中总硬度、氨氮、高锰酸盐指数、溶解性总固体、硝酸盐氮、亚硝酸盐氮、硫酸盐、氯化物8种污染指标进行研究,采用相关性分析,得到特征污染物间的相互关系,其中氨氮和亚硝酸盐氮2项指标的相关系数为0.772,总硬度和溶解性总固体2项指标的相关系数为0.670,说明上述2组指标均为显著相关。同时基于对8种污染指标的主成分因子分析,共提取了3个维度的公因子,根据各特征污染指标对3个公因子的贡献率和公因子权重,推导出因子得分公式,计算出各监测点位(含时段)的得分,结果显示,2017年枯水期下游污染监视井综合得分最高,其受污染程度也最严重,说明了地下水受污染情况有逐年加剧的趋势,且填埋场地下水污染程度与地下水井功能和降水周期有关。

In order to study the interrelation among the main pollution indexes and the pollution degree of groundwater quality in a landfill,this paper studied eight pollution indexes of groundwater,total hardness,ammonia nitrogen,permanganate index,total dissolved solid,nitrate nitrogen,nitrite nitrogen,sulfate and chloride based on 220 sets of groundwater samples from a landfill in Beijing.The correlation analysis is used for getting the relationship between the characteristic pollutants.Furthermore,to get the correlation coefficient of ammonia nitrogen and nitrite nitrogen is 0.772,and the correlation coefficient of total hardness and total dissolved solid is 0.670.The data indicated that the above two groups of indicators are significantly correlated.At the same time,based on the principal component factor analysis of eight pollution indicators,three common factors of three dimensions were extracted.According to the contribution rate and weight of each characteristic pollution indicator to three common factors,the factor score formula was derived,and the scores of each monitoring point(including time period)were calculated.On the one hand,the results showed that the comprehensive score of the downstream pollution monitoring wells was the highest and the pollution degree was the most serious in 2017,and also indicated that the groundwater pollution situation had a trend of increasing year by year,and the groundwater pollution degree of the landfill was related to the groundwater well function and precipitation cycle.