济南泉域长孝岩溶水单元水化学特征及硝酸盐污染分布

Hydrochemical Characteristics and Nitrate Pollution Distribution of Changxiao Karst Water System in Ji'nan Spring Field

摘要:

济南市保泉与供水之间的矛盾一直突出，而实现泉水保护和水资源的可持续利用之间的平衡是亟须解决的问题。长孝水文地质单元是济南市重要的地下水水源地，了解该单元地下水的水化学演化特征及水质现状是科学合理利用地下水的前提。本文利用Piper三线图、Gibbs图、饱和指数及离子比等方法研究了长孝岩溶水单元的地下水水化学演化特征并对地下水水质进行了评价，结果显示，研究区地下水主要受到岩石风化作用的控制，地下水类型较为丰富，最主要的为HCO3Ca型水。此外，区内岩溶地下水受到了不同程度的污染，部分区域硝酸根离子超过生活饮用水标准，超标区域主要分布在人口分布密集区和第四系地层较薄区域。本研究为济南市进一步科学开发利用岩溶水资源提供了科学依据。

Abstract:

The contradiction between supply and demand of water resources and spring protection is increasingly prominent in Ji'nan city. Realizing a balance between spring water protection and sustainable utilization of water resources is very urgent. Changxiao karst water system is one of the important groundwater sources in Ji'nan city. In this study, chemical composition of groundwater in Changxiao karst water system has been analyzed by pipa three line diagram method, Gibbs diagram method, saturation index method and ion proportion method. The characteristics of groundwater ions in Changxiao karst water system have been studied. It is showed that the groundwater in the study area is mainly controlled by rock weathering. The groundwater types are relatively rich, and main type is HCO3Ca. The groundwater in the study area has been polluted to a certain extent, and the nitrate ion in some areas exceeds the groundwater quality standard. The groundwater with excessive nitrate is mainly distributed in densely populated areas or areas with thin Quaternary strata. It can provide a basis for further scientific development and utilization of karst water resources in Ji'nan city.