微DEM条件下黄土高原人工掏挖地填洼量特征研究

Characteristic of Depression Storage of Artificial Dig Sloping Field in Loess Plateau Based on Micro-DEM

利用激光扫描仪获取高程,结合GIS技术模拟了黄土坡耕地人工掏挖措施下1.72×0.78 m^2大小的地表微地形模型,分辨率达0.002 m,坡度分别为5°,12°,15°,20°与25°。利用ArcGIS软件水文分析工具对模型下地表填洼量特征进行了研究。结果表明：地表坑洼空间分布比较随机,填洼量主要分布在1×10^-5-1×10^-4m^3之间;随坡度的增大,地表单个坑洼的填洼量和总填洼量逐渐减小;填洼量与坑洼深度和坑洼面积（包括坑洼投影面积和坑洼表面积）密切相关,其变化规律可用二次抛物线描述;地表填洼量大小对径流强度的影响不明显。

Through laser scanner combining with GIS technology,the micro-scale topography of an experimental cell with 1.72-by-0.78 square meters in Loess sloping field was determined at a sub-centimeter scale.Digital Elevation Models（DEM） were established at the 0.002 m scales,including 5°,12°,15°,20° and 25°.The characteristic of surface depression storage was discussed by using ArcGIS software.The results showed that the spatial distribution characteristic of depression was very random;depression storage distributes mainly among 1×10-5 to 1×10-4 cubic meters and decreases with the increases of the slope.The depression storage has close relation with depth and surface area of depression or projection area.Its change rule can be described by the second parabola.The relationship between runoff intensity and depression is uncertainty.