基于LRIS-3D建立高分辨率DEM的方法及对比研究

在基于LRIS-3D系统建立高分辨率DEM基础上，以黄土高原丘陵沟壑区桥沟小流域为对象，利用GIS工具，以三维激光扫描系统扫描数据为基础数据，研究基于DEM的数字地形特征和水文特征的提取与分析方法。研究结果表明：与普通DEM相比，高分辨率DEM提取研究区平均坡度变小、坡度标准差变大，总体地形向平坦转化，坡面曲率增大，沟壑密度增大，更详细地描述了地表特征。对流域水文过程分析、特别是对流域汇流的参数确定及汇流模型的建立有积极作用。

High Resolution DEM Extraction Based on LRIS-3D System and Its Comparative Research

Based on development of high resolution DEM with help of LRIS-3D system ; taking the Qiaogou small basin locates in hilly and gully region as test region ; using the 3D laser scanner data as base data . The paper discussed a method of using GIS technology to extract and analyze digital terrain and hydrological characteristics. The results indicate that: Comparing with the original DEM, the average slop extracted from high resolution DEM become small; Standard deviation of the slop become bigger; slop curvatures become remarkable; the gully density become complicated; and general terrain become smoothness, the landform characteristics can be described exactly. These results take positive effect in hydrological process analysis of small watershed, especially in confrim of wat-ershed concentration and in the development of concentration model.