不同比例尺DEM提取地形信息的比较分析——以重庆市为例

Comparative Analysis of Terrain Information Derived from Different Scaled DEMs(Digital Elevation Models)——A Case Study of Chongqing

以重庆市1:10万DEM为基准,比较分析1:10万与1:25万不同比例尺的DEM在地形信息容量与精度方面的差异特征.分析得出:相对与1:10万比例尺的DEM,1:25万的DEM所提取的地面坡度、坡向、剖面曲率及平面曲率4个地形因子在不同范围内都存在一定的误差,应用1:25万的DEM提取地形因子会导致一些地形信息的损失.其研究成果为了解DEM的质量及适应性提供了参考标准与依据.为进一步研究控制与消除误差都具有重要的意义.

Taking 1 ： 100 000 scaled DEMs of Chongqing as a criterion, the differences of terrain factors and accuracies between 1 ： 250 000 scaled DEMs and 1 ： 100 000 scaled DEMs were compared and analyzed. The results showed thai compared with the 1 ： 100 000 scaled DEMs, the 1 ： 250 000 scaled DEMs had considerable errors in the terrain information derived from them, including slope, aspect, profile curvature and plan curvature, indicating that using 1 ： 250 000 scaled DEMs to pick-up terrain factors will result in the loss of some terrain information. The results of this study presents a reference for understanding the quality and adaptability of DEMs and is of importance for further study of error control and elimination.