DING Hu1,2, LANG Yun-chao1*, LIU Wen-jing1,2, LIU Cong-qiang1
(1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, CAS, Guiyang 550002, China;
2. Graduate University of the Chinese Academy of Sciences, Beijing 100049, China)
Abstract: A study was conducted on variations in chemical composition of surface and spring water in a typical karst peak cluster-depression catchment, Northwest Guangxi, during two rainfall events on Aug. 23 and Aug. 24, 2007. Both spring and surface waters displayed a quick response to the rainfall in terms of water chemistry. During the rainfall events, electronic conductivity (EC) and concentrations of both dominant cations and anions, carbonate saturation index (SI) and carbon dioxide pressure (pCO2) decreased in the surface water soon after rainfall, while those factors in the spring water generally showed opposite variation trends. The solutes transportation rates of spring and stream flows increased during the rainfall period, but didn’t show a positive relationship with rainfall intensity during continuous rainfall, revealing that besides the rain dilution effect and soil CO2 effect, the pre-event water stored in the soil vadose zone, as well as the amounts of exchangeable ions may affect the transportation of ions of both spring and stream flows in the karst peak cluster-depression catchment during rainfall.
Key words: karst; Peak Cluster-Depression catchment; water chemistry; precipitation; water-rock-gas interaction
EARTH AND ENVIRONMENT Vol. 39, No.1, Tot No.283, 2011, Page 48-55
