济南泉域长孝岩溶水单元水化学特征及硝酸盐污染分布OA

The contradiction between supply and demand of water resources and spring protection is increas-ingly prominent in Ji'nan city.Realizing a balance between spring water protection and sustainable utiliza-tion 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 HCO3-Ca.The groundwater in the study area has been polluted to a certain extent,and the nitrate ion in some areas exceeds the groundwater quality stand-ard.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 wa-ter resources in Ji'nan city.