覆沙坡面产流产沙过程试验研究

Experimental Study on the Process of Runoff and Sediment Yield on Sand-covered Slope

通过对覆沙坡面产流产沙过程进行研究,以期揭示风水蚀交错区风水复合侵蚀机制,采用3个雨强（1.0mm/min,1.5mm/min,2.0mm/min）和3个覆沙厚度（0.5cm,1.0cm,1.5cm）在室内进行模拟降雨试验,分析不同雨强（覆沙厚度）下坡面的产流产沙特征。结果表明：坡面覆沙后与裸坡相比使得坡面的初始产流时间有所延长,不同雨强下延长了4.0~11.0倍,不同覆沙厚度下延长了11.0~14.0倍,初始产流时间随着雨强的增大而缩短,随着覆沙厚度的增加为延长;与裸坡对比,不同雨强下侵蚀量增加了1.9~19.0倍,不同覆沙厚度下侵蚀量大小是1.5cm〉0.5cm〉1.0cm;总之,坡面覆沙使得初始产流时间延长且在一定程度上加剧了侵蚀的发生。

Based on the study about the processes of runoff and sediment yield on sand-covered slope surface,the mechanism of aeolion-fluvial interaction in the wind-water erosion crisscross region was expected to be revealed.The indoor simulated rainfall experiments of 3rainfall intensities（1.0mm/min,1.5mm/min and2.0mm/min）and 3thickness of covered sands（0.5cm,1.0cm and 1.5cm）were carried out in order to analyze the runoff and sediment characteristics under different rainfall intensities and covered sand thickness.The results showed that the initial slope runoff time of sand-covered slope was extended compared with that of bare slope,which extended 4.0~11.0times under different rainfall intensities and 11.0~14.0times under different thickness of covered sand,and the initial runoff time shortened as rainfall intensity increased,which extended as thickness of covered sand increased.Compared with bare slope,erosion under different rainfall intensities increased by 1.9~19.0times,and the amount of erosion under different thickness of covered sand listed in the order of 1.5cm〉0.5cm〉1.0cm.In short,sandy slope made initial runoff time extend and exacerbate the erosion occurrence to some extent.