丘陵半干旱区小流域入渗产流特征研究

为了探索我国丘陵半干旱区小流域入渗产流规律,为该地区雨水径流集蓄利用和区域生态环境治理提供依据,通过人工模拟降雨和自然降雨入渗产流试验,对小流域坡耕地、林地、草地和荒地的降雨入渗产流特征进行了系统研究。结果表明,农林草地比荒地具有明显的拦蓄地表径流和减少土壤侵蚀的效果,比荒地拦蓄地表径流效率增加35.7?.0%,拦蓄泥沙效率增加46.2?.6%;利用Philip入渗理论和逐步回归分析方法对入渗产流试验结果处理分析,建立了小流域坡耕地、林地和荒地土壤的入渗产流及其相关因子数学模型;小流域产流系数与降雨小区地形坡度、降雨强度、植被盖度、土壤雨前含水量和土壤孔隙度等因子显著相关。

Study on Soil Infiltration and Runoff Generation Characteristics of Small Watershed in Hilly Semi-Arid Area of North China

The purpose of the study is to explore the soil infiltration and runoff generation characteristics of small watershed in hilly semi-arid area of North China,Which can not only provide scientific basis for soil and water loss harness,but also for raising the rainwater use rate and rainwater use efficiency.Results showed that the runoff and sediment storage efficiency in the crops,forestry and grazing lands were increased 35.7%~91.0% and 46.2%~88.6% than that in barren land,and the effects of runoff and sediment storage were very significant.Meanwhile,Philip Infiltration theory and Stepwise Regression Analysis method were used in analyzing the infiltration and runoff results of the simulated rainfall and natural rainfall experiment,and the soil infiltration fitting equations and regression equations for the correlation between runoff amount and its correlative factors of small watershed were created.These equations showed that runoff generation coefficient had a good relationship with topographic slope,rainfall intensity,vegetation cover,soil moisture content before rainfall and soil porosity factors.