Abstract
Exploring the hydrogeochemical processes of karst groundwater has significant meaning for protecting local groundwater systems in semi-arid areas. Taking a typical semi-arid karst groundwater system—the Liulin spring area—as the research region, hydrogeochemical processes from rainfall infiltration to formation of higher total dissolved solids (TDS) water were studied, applying a mass balance model and the prediction of water chemical components in the focus area was explored. The results showed that hydrogeochemical processes dominating chemical components of karst groundwater included lixiviation, cation exchange and mixture. Calcite dissolved during rainfall infiltration processes in recharge area and saturated, then precipitated along the whole flow path. CO2 dissolved significantly along with rainfall infiltration process and outgassed in discharge area and stagnant area. The dissolution of dolomite, gypsum and halite accompanied entire flow path and maximum dissolution load occurred in stagnant area. Mg-Na or Ca-Na exchange prevailed along flow path but exchange types depended on ionic concentration. The mixture between surface water and karst groundwater took place in surface water leakage belt in recharge and discharge area and mixture ratio for surface water ranged from 40% to 70%. TDS of the Liulin springs will increase with decreasing surface water leakage. Conversely, TDS of karst groundwater near Henggou area will decrease accompanied by the continuous discharge of the Henggou artesian well.
Highlights
Karst groundwater, on account of better quality, stable quantity and concentrated discharge by spring, is the major water supply source for industrial, agricultural and residential water uses in semi-arid area in northwest China [1]
There were hardly any studies focused on hydrogeochemical processes of karst groundwater from rainfall infiltration in recharge area to forming higher Total Dissolved Solids (TDS) groundwater in stagnant area
The temperature of karst groundwater generally increased along flow path with a range of 11.5 to
Summary
On account of better quality, stable quantity and concentrated discharge by spring, is the major water supply source for industrial, agricultural and residential water uses in semi-arid area in northwest China [1]. Studying hydrogeochemical processes is essential to explore hydrogeological cycle and to search reasonable exploitation plan of karst groundwater. Ma et al [16,17,18] obtained hydrological information on the surface water and groundwater and depicted karst groundwater chemical characteristics in the Liulin spring area. Zang et al [19,20] traced the source of major ions in karst groundwater using isotopic tracing techniques and hydrogeochemical methods. There were hardly any studies focused on hydrogeochemical processes of karst groundwater from rainfall infiltration in recharge area to forming higher Total Dissolved Solids (TDS) groundwater in stagnant area. According to regional hydrologic and hydrogeological conditions and in situ sampling campaign for water chemistry, hydrogeochemical processes are researched using mass balance model and prediction for water chemical components in the focus area were explored
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
