The hydrologic function and behavior of the Houzhai underground river basin, Guizhou Province, southwestern China

The genesis of the Houzhai karstic water system of the Guanling Formation, southwestern China, dates back to the Middle Triassic. Due to differences in the geomorphology and the extent of the underground river system with highly developed conduits, the hydrologic function appears to be complex. The hydrologic function and behavior of the karst system were analyzed by spring hydrograph (Mangin 1975) and by groundwater hydrochemical methods. The result obtained from the former shows that the Houzhai karstic water system behaves in a non-karstic way, with slow infiltration and a large regulation power. This study shows that Mangin's karst classification is not applicable in the karstic water systems of southwest China. The hydrodynamic parameters obtained from Mangin's spring hydrograph and the hydrochemical parameters obtained from the analysis of the bicarbonate relative frequency were combined to characterize the hydrologic function and behavior of the Houzhai karstic water system. The synthesized result shows that the distortion degree of the precipitation input is lower upstream, due to the different surface landform and the degree of karst heterogeneity. Mangin A (1975) Contribution A l'A (c) tude hydrodynamique des aquifSres karstiqus (Contribution to the hydrodynamic study of karst aquifers). ThSse, Universit, of Dijon, France (Annales de Sp,l,ologie 29(3), 283-332; 29(4), 495-601; 30(1), 21-124).