基于人工模拟降雨的黄潮土坡面侵蚀规律研究

Study on Slope Erosion Law of Yellow Tide Soil Based on Artificial Rainfall Simulation

为探讨不同坡度和雨强条件黄潮土坡面侵蚀及入渗规律,采用人工模拟降雨实验方法,选择4种坡度和3种雨强坡面产流量、侵蚀量和土壤入渗实验研究。结果表明,相同雨强坡面产流量随着坡度的增加先增大后减小,坡度9°时产流量最大。40 mm/h雨强坡面侵蚀量随坡度的增加而逐渐增大,60、80 mm/h时侵蚀量随坡度增加表现为先增大而后逐渐减小,坡度6°时侵蚀量最大。累计产流量与累计侵蚀量在3°和其他坡度时均呈线性函数关系。黄潮土埋深0.5 m以内的土壤含水率受降雨响应较为敏感,坡度影响降雨入渗速率,浅层土壤含水率变化速率随着坡度的增加先增大后逐渐减小。入渗是影响黄潮土降雨侵蚀的重要因素。

In order to explore the laws of erosion and infiltration of yellow tide soil slope surface under different slope gradients and rainfall intensities,the experimental study on runoff,erosion and soil infiltration of slope with different slope gradients(3°,6°,9°and 12°)and rainfall intensities(40 mm/h,60 mm/h,80 mm/h)is carried out by artificial rainfall simulation.The results show that,(a)the slope flow first increases and then decreases with the increase of slope gradient under same rain intensity,and is the largest when the slope gradient is 9°;(b)the slope erosion under 40 mm/h rain intensity gradually increases with the increase of slope gradient,under 60 mm/h or 80 mm/h rain intensities,it first increases and then gradually decreases with the increase of slope gradient,and the slope erosion is the largest when the slope gradient is 6°;and(c)the cumulative slope flow and cumulative erosion are linear functions at 3°and other slope gradients.The soil moisture content within 0.5 m depth of the yellow tide soil is more sensitive to rainfall,and the slope gradient affects the rainfall infiltration rate.The change rate of shallow soil moisture content first increases and then gradually decreases with the increase of slope gradient.The infiltration is an important factor affecting rainfall erosion of the yellow tide soil.