数字地形分析的理论、方法与应用

Digital Terrain Analysis:Theory,Method and Application

数字高程模型自20世纪50年代首次被提出以来,就以其简洁的数据组织方式、对地形的直观表达、简单高效的地形因子解译方法而显示了其在地学领域应用的巨大潜力。本文在全面检索和分析前人相关研究成果的基础上,首先将数字地形分析(Digital Terrain Analysis,简称DTA)的各种分析方法总结为四类,即坡面地形因子分析、特征地形要素分析、地形统计分析以及基于DEM的地学模型分析,并简要总结了每种分析方法的主要内容;其次,探讨了数字地形分析的精度及尺度问题,指出尺度效应、最适宜尺度选择以及尺度转换是DEM地形分析中的基本尺度问题;然后,论文介绍了DTA在地貌、水文、土壤、地质灾害、农业等领域的应用现状;最后,提出了数字地形分析发展方向,指出数字地形分析的概念框架亟待完善、模型构建精度有待提高、地形分析方法需要扩展,尤其是实现DEM模型嵌入的一体化分析方法,以求得到与现实世界地理环境更为接近的模拟。

Through 50 years of development,theory and methodology of DEM itself and DEM based digital terrain analysis （DTA） have been matured gradually,and played key roles in hydrology,geomorphometry,soil sciences,environmental science,agriculture,geologic hazard,civil engineering and military affairs. Based on an overall retrieval analysis of previous researches,this paper classifies different methods of DTA into four classes,i.e. analysis of terrain factor,terrain feature extraction,terrain statistical analysis and DEM based geo-modeling. Secondly,uncertainty and the scale issue of DTA are discussed. Besides,this paper points out that scale effect,optimal scale and scale transform are three basic scale issues of DTA. Thirdly,applications of DTA in geomorphometry,hydrology,soil science,agriculture,geologic hazard are introduced. Finally,this paper proposes that the conceptual framework of DTA,the accuracy of DEM modeling and the method of terrain analysis need to be improved,especially the integrated method of DEM embedded geographical modeling,for the simulation of more lifelike natural environment.