中国岩溶2023，Vol.42Issue(5)：1061-1073,13.DOI:10.11932/karst20230516
基于长期监测的济南趵突泉水文地球化学演化规律研究
Hydrogeochemical evolution characteristics of Baotu Spring in Jinan City,based on long-term monitoring
摘要
Abstract
Baotu Spring in Jinan City is of great significance in the fields of ecological regulation,history and culture,tourism economy,etc.;therefore,it is urgent to study its hydrogeochemical evolution characteristics and genesis mechanism,so as to provide a scientific basis for the high-quality protection of Baotu Spring.Based on the long-term hydrogeochemical monitoring data of Baotu Spring,its water chemical dynamic characteristics as well as its hydrogeochemical evolution over past 60 years have been analyzed in this study. The results show that the chemical composition of Baotu Spring presented a significant regularity from 1958 to 2022.The average contents of main ions in Baotu spring were HCO3-,Ca2+,SO42-, Cl-,NO3-,Na+,Mg2+and K+in a descending order,among which HCO3-and Ca2+were the dominant ions of anion and cation in spring water.The variation coefficients of SO42-and Na+contents were relatively large,indicating the varieties of groundwater environment in different periods.The variation coefficients of HCO3-,Ca2+and Mg2+contents were relatively small,showing that the source of related ions was stable.The specific gravity of SO42-,Cl-,and Na++K+gradually increased,and the hydrochemical type evolved from HCO3-Ca to HCO3·SO4-Ca.In recent years,the hydrochemical type has shown the HCO3·SO4-Ca·Na type in several periods,indicating that the water chemical components of Baotu Spring are increasingly complex and diversified.The water chemical components of Baotu Spring in the Gibbs chart showed a trend of upward shift to the right,indicating that this spring was mainly controlled by water-rock interaction,and was increasingly influenced by other factors such as human activities.The ion ratio method indicates that the mineral weathering dissolution of Baotu Spring shifts from carbonate rock to silicate rock,and the ratio of(K++Na+)/Cl-is generally below and gradually away from the line of 1∶1,indicating that there are other sources of Cl-different from those of Na+,and the sources have increased year by year.The contents of Ca2+and HCO3-ions in Baotu Spring show a gradual increasing trend,which indicates that the dissolution of carbonate rock has increased gradually.In addition,the Chlor-alkali index(CAI)shows that the water-rock interaction in Baotu Spring is dominated by the dissolution of carbonate rock,while the dissolution of gypsum and silicate rock plays a secondary role,but has gradually increased,indicating that the spring recharge area in the southern part of the gypsum and silicate rock stratum has a stronger recharge effect on groundwater runoff in Baotu Spring.The cation exchange in Baotu Spring is weak on the whole,but it has gradually increased over the years,and the cation exchange is stronger in the dry season than the wet season.The mineral saturation index of Baotu Spring is in a supersaturation state as a whole,and its dispersion becomes larger with the passage of time.Over the years,the mineral saturation index of Baotu Spring during the wet season has been generally higher than that during the dry season and normal season,but the performance is various in different periods.From 1950s to 1980s,the mineral saturation index of Baotu Spring during the wet season was lower than that during the dry season,and the mineral saturation index of Baotu Spring during the wet season was higher than that during the dry season after 1990s,indicating that with the increase of human activities in different historical periods,the source of groundwater and the water-rock interaction changed in dry and wet seasons.The contents of NO-3/Cl-and Cl-increased first and then decreased under the influence of agricultural activities and domestic sewage discharge.In 1950s-1960s,the contents were greatly influenced by agricultural activities.Since 2000s,with the continuous improvement of spring protection and ecological environment,agricultural activities have gradually weakened the effect,while the influence caused by emission of domestic sewage and other human activities have been strengthened by degrees.Due to the influence of other human activities other than gypsum dissolution,the contents of SO42-have increased gradually since 2010s. In summary,in the quasi-natural state from 1950s to 1960s,the contents of chemical components of Baotu Spring were relatively low.From 1970s to 1980s,the contents were increasingly influenced by agricultural activities,industrial and mining activities and domestic sewage discharge.From 1990s to 2000s,the contents of NO3,Cl-and SO42-gradually increased under the comprehensive influence of human activities such as agricultural pollution in the recharge area,industrial and mining activities,domestic waste landfill,etc.Since 2010,the pollution of industrial and mining enterprises and domestic life has alleviated,and the protection measures of Baotu Spring such as ecological groundwater recharge have become normal.The contents of Ca2+and Mg2+in non-carbonate karst hydrolysis increased gradually,and the contents of Cl-and SO42-affected by human activities increased significantly.The research shows that the water chemical components of Baotu Spring have mainly come from the water-rock interaction since 1958,and the influence of human activities has been increasing continuously.In different historical periods,different human activities(agricultural activities,industrial and mining activities,groundwater recharge,etc.)have different effects on the hydrogeochemical evolution of Baotu Spring.关键词
趵突泉/水文地球化学/演化规律/矿物饱和指数Key words
Baotu Spring/hydrogeochemistry/evolution characteristics/mineral saturation index分类
天文与地球科学引用本文复制引用
柳浩然,张文强,刘文,马雪莹,关琴,张海林..基于长期监测的济南趵突泉水文地球化学演化规律研究[J].中国岩溶,2023,42(5):1061-1073,13.基金项目
山东省地质勘查项目(鲁勘字(2021)46号) （鲁勘字(2021）
自然资源部/广西岩溶动力学重点实验室开放基金(KDL201804) （KDL201804）
山东省地矿局八○一队科技创新项目(2022JBGS801-13) （2022JBGS801-13）
山东省地矿局地质勘查与科技创新项目(HJ202110) （HJ202110）
