吉林市城区地下水污染时空演化

通过提出投影寻踪地下水污染指数模型,求得吉林市城区1980~2009年地下水监测井的污染指数.同时考虑第二松花江两岸地下水污染的非连续性,用修正的局部多项式插值方法对各年污染指数进行分区插值,得到各年地下水污染指数分布图.结果表明,吉林市城区地下水受到不同程度的污染,地下水污染指数普遍偏高,江北片区污染最为严重.全区在时间演化上具有“轻-重-轻”的阶段特征,地下水污染时空演化规律与人类活动方式紧密联系.吉林市城区地下水主要污染因子为“三氮”,其中NO2-对地下水污染的影响最大,对地下水污染指数的贡献度多年保持在0.7上下.

Spatio-temporal evolution of groundwater pollution in the urban areas of Jilin City

Projection pursuit method was adopted to establish groundwater pollution index model. Correspondingly, groundwater pollution indexes of monitoring wells from 1980 to 2009 were calculated. Considering the non-continuity of groundwater pollution between the both sides of Songhua River, modified local polynomial was used to complete interpolation of pollution indexes sub-regionally. Then distribution maps of groundwater pollution indexes from 1980 to 2009 showed. The results showed that, groundwater was contaminated in all districts with different severities for region-widely high groundwater pollution indexes, especially in Jiangbei district. The groundwater pollution in all districts revealed a ight-severe-light character in the time revolution. Spatio-temporal evolution of groundwater pollution in this region was closely linked with human activities. From the analysis of the contributions of all pollution factors to groundwater pollution indexes in each year, a conclusion could be drawed that, nitrite, nitrate and ammonia were the main factors affecting the groundwater environment, while nitrite was the dominant one with a contribution rate of 0.7 up and down in most years.