The Characteristics of Water Balance in Rice-based Cropping System Based on the Distributed Model-model Development

摘要

According to the characteristics of irrigation system in Southern China,irrigation water movement and paddy rice field module in SWAT are improved in this article.A close small watershed in Zhanghe irrigation system is selected,to investigate the hydrological cycle process and water budget using the improved SWAT model.The site selection is divided into several subbasins based on DEM and channel layout.The land area in a subbasin is divided into hydrologic response units (HRUs),and hydrologic response units are portions of a subbasin that possess unique land-use,management and soil attributes.The model is calibrated and validated against the observed daily outflow,and the results indicate that the improved SWAT model adapts well to the water balance and water transformation of rice-based cropping system in China's southern region.