Preliminary study on the method and structure of the distributed hydrological model for karst irrigation area in Southwest China

The water circle in karst irrigated area is complex, and the distributed hydrological model is a useful tool for studying the influence of human activity and climate change on the hydrology in karst irrigated area. A distributed hydrological model for karst irrigated area is developed based on SWAT (Soil and Water Assessment Tool) aiming at the hydrologic characteristics of the karst irrigated area in Southwest China. The epi-karst zone water circle module, karst water in shallow aquifer module, subterranean river system module, irrigation function of pond and canal seepage module are added into SWAT, and the paddy field water balance module in SWAT model are modified. The spatial discretization method for karst irrigated area and the model structure are analyzed in the article. The model developed is valid in the karst irrigation area, and it is open.