Analysis of Karst spring discharge in semiarid of China

Jinci spring is one of the most noted karst spring in the semiarid part of northern China, and the spring dried up in 1994 due to long time groundwater overexploitation. Statistics analysis method was used in this paper to capture the relationship between the spring discharge and its influence factors, and the analysis is based on the long time series of observation data from 1956 to 1994. It is shown that the groundwater abstraction was the major factor of the depletion of spring discharge, and groundwater overexploitation is mainly because the lack of surface water resource and mining drainage of this area. Reduction of precipitation is another key factor controlling the evolution of the spring discharge, and the time-lag of rainfall recharge is 2 year in Jinci spring area. Groundwater level decline is also a signal of groundwater overexploitation, and the spring discharge is a function of groundwater level in the karst area. Karst spring discharge curve was analyzed to show the relation of spring discharge and water level, and a function was deduced based on the observation data records. This research can be a scientific guideline to the Jinci spring reflowing management.