地形因素是影响土地利用空间布局的重要因素之一。以湖南省浏阳市为例,应用TM遥感影像数据及DEM数据,在ArcGIS空间分析模块支持下,采用高程梯度、坡地梯度和地形梯度三种方法对比研究,通过分析不同土地利用类型在三种地形梯度上的分布指数,揭示研究区域的土地利用类型分布的模式及其与地形因素之间的对应关系。结果表明:耕地、园地、其他农用地和建设用地主要分布在较低的地形梯度上,分布指数随着地形梯度的增大而减少,逐渐趋向于0,以上同种土地利用类型在三种地形梯度上的分布具有一定的相似性;林地主要分布在中高等级高程、较高坡度和较高等级地形位上,而未利用地分布区域却相反;对三种研究方法的比较表明,地形位综合了高程和坡度的信息,能更方便地反映土地利用类型随地形变化的分布趋势;而地形位指数则可以更有效地反映土地利用类型的分布特征。本研究可为区域土地利用布局研究提供一种可行的定量分析方法。
Terrain is not only one of the important factors affecting the spatial layout and land use change,but also a prerequisite for land evaluation and land planning.A good understanding of the relationships between land use types and terrain gradient is essential for land management.In this paper,elevation,slope,and terrain niche were conceptually divided into 13 classes,which were used to describe the terrain difference across the study area,Liuyang City in Hunan province.The nondimensional distribution index was used to examine characteristics of land use types.Using Landsat TM satellite imagery,DEM,and other materials from field survey based on the spatial analysis module in ArcGIS,the distribution pattern of land use types and their relationships with terrain factors in the study area were revealed by analyzing the nondimensional distribution index for different land use types on varying terrain gradients.Results showed that:1)cultivated land is mainly distributed in areas ranging in elevation from 36 m to 200 m,in slope from 0o-12o,and in terrain niche from 0 to 0.39.Orchard is mainly distributed in areas ranging in elevation generally from 36 m to 200 m,in slope from 0oto 15o,and in terrain niche from 0 to 0.54.Other agricultural land and construction land are primarily distributed in areas ranging in elevation from 36 m to 200 m,in slope from 0oto 12o,and in terrain niche from 0 to 0.54.Forestland is mainly distributed in areas ranging in elevation from 200 m to 1200 m,with slope larger than 12o,and terrain niche larger than 0.39.Unused land is mainly distributed in areas with elevation larger than 1200 m, slope ranging from 0oto 6o,and terrain niche greater than 1.09.Also,the interrelationship between land use types and terrain gradient showed a significant correlation;2)cultivated land,orchard, other agricultural land,and construction land are distributed mainly on the lower terrain gradients. The distribution index decreases with increasing terrain gradients,gradually approaching zero.The same land use