岷江上游干旱河谷耕地和居民用地的空间特征

以岷江上游干旱河谷耕地和居民用地为对象,用景观格局分析软件FRAGSTATS3.3计算了4个景观格局指数,利用ARCMAP9.0分析了耕地和居民用地与其它景观类型间的空间邻接特征,基于数字高成模型(DEM)研究了耕地和居民用地与海拔及坡度的关系。结果表明:灌木林地是干旱河谷的景观基质;耕地和居民用地斑块的平均面积和密度较小,形状简单;耕地大多在1700~3000m的区域,陡坡耕种比较严重,与灌木林地具有较高的邻接长度和数目;居民用地间隔较远,在低海拔地区分布相对较密,高海拔地区分布比较分散;对居民用地在空间结构影响最大的是耕地的分布。

Spatial characteristics of farmland and residential land in dry valley of Minjiang River upper reaches

By using FRAGSTATS 3.3 software,this paper calculated the total area,patch number,patch density,and fractal dimension of the farmland and residential land in dry valley of Minjiang River upper reaches based on the spatial neighboring properties of the farmland and residential land analyzed by ARCMAP 9.0 and the relationships between their distribution and topographic factors altitude and slope studied based on DEM.The results showed that shrub land was the landscape radix of the dry valley.The farmland and residential land in the valley had small mean patch size and patch density,and their shapes were simple.Most farmlands were distributed on the steep slopes at the elevations ranging from 1 700 to 3 000 m,and adjacent to shrub land patches.Residential patches had far distances among each other,with a relatively dense distribution at low altitude,but very sparse distribution at high altitude.The spatial distribution pattern of residential land was most affected by that of farmland.