基于DEM的醴陵市土地利用空间格局分析

地形是土地利用空间格局形成的基础，本文利用遥感影像、土地利用现状图、地形图、地貌图，以及野外实际调查资料，通过建立DEM、地貌分区、高程分级、叠加分析等过程，以地貌分区和高程分级区域为基本空间单元，分析了湖南醴陵市土地利用空间格局及与地形因子的关系。结果表明土地利用类型空间分布具有强烈的区域差异性，各地貌分区与高程分级区域的土地利用组合不同，同一土地利用类型在不同地貌分区和高程区域的分布存在差异；土地利用类型空间分布与海拔高程具有显著的相关性，随海拔高程增加，林地分布比例增大，耕地、园地、城乡居民用地、工矿用地、水域和未利用土地均呈减少趋势。在此基础上，构建了研究区土地利用空间格局的三维景观模型，直观地再现了土地利用空间格局与所处环境的关系，有利于辨识不同地貌部位土地利用的分布规律与差异，可为研究区农业结构调整和土地资源可持续利用提供参考。

Analyzing Spatial Pattern of Land Use in Liling City based on DEM

Based on remote sensing image, land-use map, topographic map, geomorphologic map and other materials from field survey, the study analyzed the spatial pattern of land use and the relationship between land use and topography in Liling city by creating DEM, geomorphologic zoning, and altitude classification. The results showed that: 1) The area of forestland, which is distributed all over the mountain area or foot of the hill, occupied 54.7% of the total. The area of paddy field, which is distributed on the valley plain under the altitude of 200m, accounted for 25.7% of the total. Rural settlement place located on the foot of the hill or on the valley plain is the third largest land use type, accounting for 7.7. The area of the dry land, orchard, industrial land, water bodies and unused land occupied 3.3%, 1.7%, 0.8%, 4.3% and 2.1% respectively; 2) Spatial distribution of land use types is characterized by strong area differentiation. There are different land use types associated with geomorphologic zoning and altitude classification. Even though it is the same land use type, the spatial distribution is diversified in different geomorphologic sub-area and altitude sub-zone. Also, the interrelationship of land use types and altitude showed a significant correlation. With the rise of altitude, the area of forestland increased, but the area of cultivated land, orchard, settlement, industrial land, water body, and unused land decreased; 3) Terrain is the primary factor affecting land use spatial pattern in Liling. In addition, human activities have a strong influence on the spatial distribution of land use. In high altitude area, forestland is the dominant land use type and the degree of human intervention is relatively weak there. In low altitude area, the intensity of land use is strong and land use types are changed frequently; 4) Three-dimension visualization technology was used to display intuitively the land use spatial pattern and the interrelationship of land use distribution and environment in the study area, Which makes supports to decision making in adjustment of agricultural structure and sustainable utilization of land resources.