松嫩平原北部土地利用变化的地形梯度特征分析

ANALYSIS ON TERRAIN GRADIENT CHARACTERISTICS OF LAND USE CHANGE IN NORTHERN SONGNEN PLAIN, CHINA

地形地貌是影响土地利用结构变化与空间格局分布的重要自然要素,不同地形梯度下的土地利用变化格局是自然条件与经济社会条件相互作用的体现。以松嫩平原北部典型区域——黑龙江省嫩江县为研究区,综合利用遥感和地理信息系统技术,通过DEM提取高程、坡度和坡向地形因子,并结合地形位指数和分布指数,分析研究区土地利用变化地形梯度特征。研究结果表明:1)1984—2011近30年间,研究区土地利用变化主要集中在高程313～397 m,坡度5～15°的半阳坡地区,并随着高程的增加、坡度的增大而减缓,阳坡大于阴坡;2)1984—2011年,研究区土地利用变化地形梯度特征明显,在不同梯度等级,土地利用类型之间的转换不同。该研究成果可以为土地利用结构的优化及合理布局提供科学依据。

Landform is an important natural element which affects the land use structure change and the spatial distribution pattern. The pattern of land use changed under different terrain gradient was the embodiment of the natural conditions and economic and social interaction. This paper took Nenjiang county in Heilongjiang province, a typical area in northern Songnen plain as the study area, comprehensively used the RS and GIS technology, extracts elevation, slope and slope aspect factors by DEM, combined with the topographic index and distribution index, analyzed the terrain gradient characteristics of land use change. The results show that： 1 ） in the study area in near/y 30 years from 1984 to 2011, land use change were mainly concentrated in sunny slope region with elevation of 313 - 397m, slop in 5° - 15°half; and with the increase of elevation and slope, the trend was slowing down, and the sunny slope was greater than the shady slope; 2） 1984-2011, land use change in the study area showed terrain gradient characteristics significantly, in different gradient level, the conversion between different land use types were different. The resuhs could provide scientific basis for the optimization and rational distribution of land use structure.