Infiltration coefficient of precipitation in karst peak-cluster depression area:A case study of Zhaidi karst underground river basin

The precipitation infiltration coefficient α and groundwater runoff modulus M are the most basic hydrogeological parameters.In this paper,based on the high frequency monitoring data of water level, flow, precipitation of Zhaidi karst underground river basin in a hydrological year from March 2013 to February 2014,the precipitation infiltration coefficients for dry season, normal season and rainy season have been computed by means of water balance method,which are 0.352, 0.528, 0.726,respectively, and the average infiltration coefficient is 0.635. The groundwater runoff modulus are 8.32,19.80,61.15 L·s-1·km-2, respectively for the above three seasons, and the average annual runoff modulus is about 33.36 L·s-1·km-2. The calculation method and values of precipitation infiltration coefficient and groundwater runoff modulus have certain reference significance in water resources evaluation for the same karst area.