基于REW模型的半湿润半干旱地区水文模拟与产流机制分析OA

Accurate prediction of floods in semi-humid and semi-arid basins relies on a precise representation of runoff generation mechanisms.This study applies the physically based Representative Elementary Watershed(REW)model to simulate flood processes in the Yangquan(semi-humid)and Chabagou(semi-arid)basins.By analyzing the dynamics of saturation-excess and infiltration-excess runoff components directly derived from the model,we quantitatively identify the runoff generation patterns and their dominant controlling factors.Results show:① The Yangquan Basin achieves higher simulation accuracy(ENS=0.73 for both calibration and validation periods),with runoff generation varying between mixed saturation-infiltration mechanisms and infiltration-dominated single mechanisms.② The Chabagou Basin exhibits lower accuracy(ENS=0.68 and 0.51),where runoff is consistently dominated by infiltration-dominated single mechanisms controlled by rainfall intensity.③ The runoff mechanism is more diverse and dynamically modulated by both soil moisture and rainfall in semi-humid regions,whereas it is singular and intensity-driven in semi-arid regions.The REW model effectively captures these processes,supporting improved flood forecasting across different hydroclimatic settings.