Study on the Relationship Between Groundwater and Surface Water in Xinjiang Kongque River Basin Using Isotopes and Hydrochemistry method

Groundwater in the Kongque river basin, as one of the main water sources for agricultural irrigation, plays an increasingly important role in the economic development. In order to realize the rational exploitation of water resources and ecological protection, relationship between groundwater and surface water in the Kongque river basin were studied using environmental isotopes and hydrochemistry method. The results show that the main groundwater recharge is from river water. Both the genetic types of aquifers and the distribution of modern channels have effect on the spatial distribution of groundwater quality. The hydrogen-oxygen stable isotopes are good indicators on the transformation among different water bodies, but it is difficult to distinguish the Pleistocene and Holocene groundwater. The combination of ³H and ¹⁴C has a good indication on the circulation and renewal ability of groundwater. ¹⁴C age variations can well indicate the direction and rate of confined groundwater flow. ¹³C can be used to preliminarily determine groundwater types or age as a reference indicator.The surface water-fed irrigation have increased the recharge and renewal capacity of the unconfined groundwater,whereas the exploitation and utilization of confined groundwater rely mainly on old groundwater with poor renewal capacity. The extraction of confined groundwater in the agricultural irrigation areas in the middle reaches of Kongque river should be reduced, while in the lower reach of the salty groundwater areas the extraction of unconfined groundwater should be increased in order to lower groundwater level,reduce soil salinization and promote the sustainable use of land and water resources.