湄潭县城规划区景观指数的粒度效应分析

基于贵州省湄潭县2010年航拍遥感影像与2007年的TM(thematic mapper)图像,利用ArcGIS 9.3软件、Fragstats 3.3和SPSS软件,选择了15个景观指数,分析了湄潭县景观指数随粒度变化表现出来的粒度效应,并对景观指数的曲线拟合函数进行了分析与计算.结果表明:在选取的粒度范围内,随着粒度大小的变化,大多数景观指数都表现出明显的粒度效应,说明景观指数对粒度具有尺度依赖性.选取的15个景观指数的粒度效应可以分为总体上升、平稳降低后稳定、波动降低、波动降低后稳定和不规则变化5种情况.另外,数据源分辨率的大小对景观指数的粒度效应也有一定影响.部分景观指数随粒度变化响应的曲线分别可以用线性函数、二次函数、三次函数、反函数、幂函数和对数函数进行拟合.对于湄潭县而言,利用航拍遥感影像进行景观指数分析的适宜粒度范围是2-10 m,利用TM图像进行景观指数分析的适宜粒度范围是55～65 m；建议选取高分辨率影像数据对该研究区的景观格局特征进行分析.

Landscape indices with sensor grain size changes in Meitan County, China

Based on the aerial remote sensing image of Meitan in 2010 and the thematic mapper（TM） image of Meitan in 2007,the grain size effect and fitted functions of 15 selected landscape pattern indices,which were divided into five categories of amplitude-accreting： stable decreasing and then stable,undulatory decreasing and then stable,undulatory decreasing,and anomalistic changing,from Meitan County were analyzed with ArcGIS 9,Fragstats 3.3 and SPSS software.Results showed that for the range of the grain size,most of the selected indices had an effect on grain size and there response curves could be fitted with linear function,quadratic function,cubic function,inverse function,power function and logarithmic function.To research the landscape of Meitan County,a suitable range for grain size when computing and analyzing landscape indices was 2-10 m with an aerial remote sensing image and 55-65 m with a TM image.To improve the results,high-resolution image data could be utilized to analyze the landscape pattern of Meitan County.