间歇性降雨条件下辽西地区坡面细沟形态特征变化试验研究

Experimental Study on Morphological Characteristics of Rills on Slopes in Western Liaoning under Intermittent Rainfall

风蚀和水蚀相互作用是我国北方半干旱地区水土流失的重要原因。以辽西地区风水蚀综合作用区为例,利用实验室试验的方式对辽西地区坡面细沟形态特征变化进行研究,获得了黄土坡面与覆沙黄土坡面在间歇性降雨条件下的细沟形态参数变化特征及其相关关系,结果表明:前两场降雨是黄土坡面细沟的快速形成阶段,而后续场次降雨是细沟稳定发育阶段;覆沙黄土坡面在第三场降雨后细沟发育基本稳定,其侵蚀程度要大于黄土坡面;黄土坡面和覆沙黄土坡面细沟的累计长度、平均宽度和平均沟深之间均呈现出较好的线性关系,属于一个相互耦合的协同作用系统。

The interaction of wind erosion and water erosion is an important cause of soil erosion in the semi-arid areas of northern China. Taking the combined action area of wind erosion and water erosion in western Liaoning province as an example,the morphological characteristics of rills on the slopes of western Liaoning were studied by means of laboratory experiments. The variation characteristics and correlation of the morphological parameters of rills on the loess slope and sand-covered loess slope under intermittent rainfall conditions were obtained. The outcomes show that a) the first two rainfalls are the rapid formation stage of rills on loess slope,the next rainfalls are the stable development stage of rill;b) after the third rainfall,the development of rills on the sand-covered loess slope is basically stable and the degree of erosion is greater than that of loess slope and;c) the cumulative length,average width and average depth of rills on the loess slope and sand-covered loess slope all show a good linear relationship,belonging to a mutual coupling cooperative system.