西双版纳地区道路发展对景观格局的影响

近年来西双版纳地区的道路建设和发展加速了生物栖息地破碎和生态系统的退化.为了探明该区道路网络与景观格局的内在联系,定量判断道路对景观格局的影响范围,根据该区1976、1988、1999和2010年4期Landsat MSS/TM/ETM影像解译的土地利用数据,利用ArcGIS软件的缓冲区分析方法与移动窗口法分析了近34 a来该区内道路发展对景观格局的影响.结果表明:①随着道路密度的增加,西双版纳景观破碎化程度增加;②距道路越近,自然景观面积百分比越小,人工景观面积百分比越大;③道路的影响距离是第2等级道路>第1等级道路>第3等级道路;④道路对景观的影响面积随道路密度的增加而增加,第2等级道路的影响面积最大,第1等级道路对景观的影响距离和影响面积增加幅度均最大.

Effect of road development on landscape pattern in Xishuangbanna

In recent years,the ecology system in Xishuangbanna was severely influenced by the construction and development of roads,which caused fragmentation of biological habitat and degradation of ecosystem.In order to investigate the internal relation between the roads network and landscape pattern,and also quantitatively estimate the effect on landscape caused by different classes of roads in Xishuangbanna since 1976,we assessed the effect of roads development on landscape pattern based on four land-use maps (1976,1988,1999,2010),which were interpreted from the Landsat MSS/ TM/ ETM imageries.The assessment was made by buffer analysis tool in ArcGIS 9.3,moving split-window techniques (MSWT) was also employed.The results showed that the fragmentation of landscape increased by increasing roads density.The percentage of natural landscape areas decreased by increasing distance to the roads,while the percentage of artificial landscape areas(i.e.rubber plantation,farmland,building site) increased at the same time.The distance between the roads and affected landscape showed significant difference among three main class roads as: the second grade roads>the first grade roads>the third grade roads.The affecting distance increased faster in the first grade roads.The percentage of the four-type landscape areas affected by the roads increased by increasing density of the roads,the second grade roads exerted the greatest influence on the area of affected landscape.The largest increasing extent was demonstrated in the first grade roads both in the affected areas and distance from the roads during the past 34 years.