区域水土流失地形因子的地图学分析

Cartographic Analysis on Terrain Factors for Regional Soil Erosion Modeling

地形是影响区域水土流失的主要因子。基于中小栅格DEM提取的坡度是区域水土流失地形因子的主要指标之一。根据地貌学和地图制图学论文分析和对地形图及其DEM图形分析表明，在一定比例尺范围内（1：1万～1：25万），多种比例尺的地形图均能表现区域地形的宏观结构特征；随着DEM分辨率的降低，在DEM上量算得到的坡度不断趋于平缓；由于制图综合不直接影响高程的数值，所以中小栅格DEM表现地面起伏的能力是存在的，只是发生了一定的变形而已。

Slope gradient is one of main factors for regional soil erosion modeling. Based on micro-geomorphology and cartography theory and digital terrain analysis, it shows that macro features of geomorphology could be depicted by topographic maps at multiple scales, but the slope extracted from DEMs become gentler along with the DEM resolution become coarser, but capacity to represent the land relief is keep in some extent because have no direct cartographic generalization to elevation.