黄土高原丘陵区景观特征与景观指数粒度效应研究

Landscape Pattern Characteristics and Grain Effect of Landscape Index in Loess Hilly Region

选取黄土丘陵沟壑区高家沟流域为研究区,基于遥感图像绘制流域土地利用景观图,利用GIS相关软件以及景观格局分析软件Fragstats,计算高家沟流域的景观格局指数,并在景观水平上对指数的粒度效应进行了研究。结果表明:草地为高家沟流域土地利用类型的主体,园地稀少,各土地利用类型布局分散,斑块形状较复杂,土地利用结构不够合理;粒度变化对景观指数的计算具有重要影响,各景观指数均具有明显的粒度效应,不同的景观指数随粒度增加表现出不同的变化趋势:(1)景观指数随粒度的增加有明显的下降趋势;(2)景观指数随粒度的增加变化趋势不明显,或上升或下降,并呈现出一定的波动性。高家沟流域景观分析的适宜粒度范围为75～120m。

Taking Gaojiagou Basin as study area,based on RS（Remote Sensing） technologies,the landscape map was made.In order to analyze the grain effects at the landscape level,GIS（Geographic Information System） software and landscape pattern analysis software Fragstats were used to calculate landscape pattern indices of Gaojiagou Basin.The results showed that the grassland was the dominant land use type in Gaojiagou Basin while the garden plot was small and the structures of many land use types were unreasonable with complicated patches as well as scattering distribution;grain change had great effects on landscape index calculation and different indices had different grain effects：（1） landscape indices showed a gradual downward trend with the increasing grain size;（2） landscape indices showed the unobvious trend with the increasing grain size,and it was fluctuation.The grain size which was suitable for analyzing the landscape in the study area should be 75~120 m.