莆田市土地利用格局的地形梯度特征变化及尺度效应

以莆田市1995年、2005年和2015年3期遥感影像和高程数据(DEM)为数据源,借助RS和GIS技术,运用地形位指数、土地利用类型分布指数和景观格局指数,对莆田市1995—2015年间土地利用格局在地形梯度上的分布特征、变化历程及空间尺度效应进行了系统分析。结果表明:(1)林地主要分布在高地形位区域,建设用地与水体主要分布在低地形位区域,农用地与裸露地主要分布在低、中地形位区域。(2)1995—2015年间,建设用地与农用地的主要分布区域逐步向较高的地形位区域扩张;林地与水体的优势分布区段并未发生变化。(3)尺度效应研究表明香农多样性指数、香农均匀度指数和蔓延度指数等在不同地形位上均不具尺度效应;斑块密度、景观形状指数和面积加权分维指数在不同地形位上均随尺度增加而减小。

Characteristic change and scaling effect of the land use pattern in Putian city based on the terrain gradient

Based on a digital elevation model (DEM) and three remote sensing images of Putian city in 1995,2005 and 2015,and with the help of the Remote Sensing and Geographic Information System technology,the characteristic of temporal and spatial changes of the land use pattern and scaling effect were systematically analyzed using terrain niche index,distribution index and landscape pattern index.Results showed that:(1) Forestland is mainly distributed in the high terrain sections,while construction land and water area,agricultural land and bare land are mainly distributed in the low terrain sections,and the low and middle terrain sections,respectively.(2) From 1995 to 2015,the main distribution area of construction land and agricultural land had been gradually expanded to the high terrain area,and the dominant distribution ranges of forestland and water area had not changed.(3) The landscape indexes that did not show scaling effect in any terrain sections were Shannon's diversity index,Shannon's evenness index and contagion index,while the landscape indexes that decreased with an increase of scale were patch density,landscape shape index and area-weighted mean fractal dimension index.