土地利用/覆被变化的驱动力模型研究——以嫩江中上游地区为例

The driving forces of land use/cover change in the upstream area of the Nenjiang River

通过遥感手段获取嫩江中上游地区 1 995年和 2 0 0 0年的土地利用 /土地覆被图及其变化图 ,在GIS支持下 ,生成两个时段该区的土地利用程度变化图 ,分析土地利用程度变化的驱动力 .选取的自然因子主要为高程 (e)、坡度(s)、人口 (Δp)、大牲畜头数 (Δl)、农业机械力投入量、土地覆被类型变化区距嫩江干流和居民点的最短距离等 ,利用空间相关分析筛选出主要影响因子为高程、坡度、人口、大牲畜头数 .利用空间多元线性回归函数求得本区土地利用程度变化模型ΔLa=1 1 .0 3 7-4 .51 2 e -0 .2 98 s + 0 .2 92 Δp + 2 .596 Δl.

Based on the Landsat TM5 and TM7 images, the land use/cover change was detected in the upstream area of the Nenjiang River between 1995～2000. With the spatial analysis techniques of GIS, the maps of land use degree and its change during this time period were produced. To identify the cause of changes, the elevation and slope was regarded as the main natural influencing factors and were transformed from coverage format to grid format within GIS. The thiesson polygon method was used to the spatial allocation of soci-economic factors including human population, livestock numbers, mechanizing power of farming and the nearest distance from changed pixel to the trunk stream and to main settlements, thereby the spatial relationship between land use degree change and social-ecomic factor variation were analyzed. According to results of the spatial correlation analysis, the determinants of changes in land use/cover i.e. elevation, slope, population density change, livestock increase were extracted in quantitative analysis method in this area.