基于土壤地形指数和下垫面水文分区的流域模型参数率定

针对流域水文响应会受到地质、地形、地貌、植被、土壤等自然地理因素以及土地利用等下垫面因素综合作用的特点,根据流域下垫面的地理特征进行水文响应分区。借助遥感资料对流域下垫面进行分类并获取土地覆盖/土地利用信息,结合流域土壤类型数据与地形指数推求流域的土壤地形指数。进一步地,利用遥感分类信息和土壤地形指数进行流域的水文分区,率定各个水文分区SCS模型的参数CN值并进行水文模拟,结果表明,屯溪流域21次和东湾流域32次洪水径流模拟相对误差均比传统方法的小。

Parameter calibration for watershed hydrology model based on soil topography index and hydrological partition of underlying surface

Because the hydrological response of watersheds is comprehensively affected by physical geographical factors, such as geology, topography, landforms, vagetation, and soil, and underlying surface factors, such as land use, hydrological partition was conducted based on the geographical characteristics of underlying surface of watersheds. The underlying surface of watersheds was classified with remote sensing data and information on land cover and land use was obtained. By combining data of watershed agrotype and the topography index, the soil topography index was calculated. Furthermore, taking advantage of the remote sensing data and soil topography index, hydrological partition was conducted, the parameter C_N of the SCS model was calibrated in every hydrological subregion, and hydrological simulation was conducted. The results showed that the relative error was less with the proposed method than with the traditional method in 21 flood runoff simulations in the Tunxi Watershed and 32 flood runoff simulations in the Dongwan Watershed.