永城市浅层地下水污染分布特征及来源识别

为有效管理和保护永城市浅层地下水资源,维系水资源可续利用,必须查明其污染物的分布特征和来源。在对永城市浅层地下水采样分析的基础上,结合分析城市发展带来产业布局改变及土地利用类型分布对其造成的影响,研究其主要污染组分的来源及分布特征。结果表明:城市第二产业(工矿业)发展,GDP的增长与浅层地下水中ρ(SO₄^2-)、ρ(NO₃^-)上升存在相关性,城市工业及人口密集区与污染严重区位置趋于一致。浅层地下水污染的最主要来源是SO₄^2-含量的上升,除了直接导致水质变差外,还会间接改变水文地球化学作用的强度,造成原本难溶的碳酸盐和硅酸盐的溶解量增大,使得ρ(TDS)进一步上升而改变水质。其次,NO₃^-、COD也是浅层地下水主要的污染来源,其部分来源工业废水,部分来源于农业上农药和化肥的过量使用。

Distribution characteristics and source identification of shallow groundwater pollution in Yongcheng City

In order to effectively manage and protect the shallow groundwater resource in Yongcheng City and maintain the sustainable utilization of water resource, distribution characteristics and sources of pollutants must be identified.On the basis of sampling and analysis of shallow groundwater, this paper studies the sources and distribution characteristics of main pollution components, combining with the influence of industrial layout change and land use type distribution caused by urban development.The results show that the growth of urban secondary industry (industry and mining) and GDP are correlated with the increase of SO₄2- and NO₃- contents in shallow groundwater, the dense areas of urban industry and population tend to be the same as the seriously polluted areas of shallow groundwater.The main source of shallow groundwater pollution is the increase of SO₄2- content, in addition to directly causing the deterioration of water quality.It also indirectly changes the intensity of hydrogeochemical action.It leads to an increase in the dissolution of the insoluble carbonate and silicate, which further increases the content of TDS and changes the water quality.In addition, NO₃- and COD are also the main pollution sources.It comes partly from industrial waste water and partly from the excessive use of pesticides and fertilizer in agriculture.