利用多波段遥感影像数据和地理信息系统技术,结合植被图及外业调查,采用多个景观格局指数首次定量分析新疆额尔齐斯河流域景观空间格局及破碎化特征。借助ERDAS image8.7软件,将额河流域景观类型划分为7大类10小类,其中包括5大类8小类植被类型,影像总的分类精度达到87.2%。5大类植被类型面积比例分别为耕地16.5%、河漫滩林地2.6%、湿地1.6%、草地10.5%、荒漠52.2%。格局指数分析表明:河漫滩林地在景观中呈小斑块分布,其斑块最大周长和最大面积及平均面积均小于其他植被类型;河漫滩林地的斑块形状比较复杂,其平均斑块形状指数、平均斑块分维数和类型边界密度指数均高于其他植被类型;多个景观指数都表明河漫滩林地在景观中的破碎化程度最高,这主要是由于河漫滩林地丰富的生物多样性和资源富集性吸引了人类高强度的干扰所致。额河流域景观类型面积分布最不均匀,但景观类型斑块数分布相对较均匀。
The landscape pattern and fragmentation in Beitun of Irtysh River Basin in Xingjian was analyzed by using RS and GIS in combining with the vegetation maps and field investigations. Quantitative indices of landscape pattern were chosen to examine landscape pattern and fragmentation. By using the software ERDAS image8.7, 7 primary landscape types and 10 secondary landscape types were classified, which including 5 primary vegetation types and 8 secondary vegetation types. The total classification accuracy was 87.2%. The primary vegetation types area percentage of farmland, riparian forest, wetland, grassland and desert vegetation was 16.5 %, 2.6 %, 1.6 %, 10.5 %, and 52.2 % respectively. The patch maximal perimeter, patch maximal area and mean area indices of riparian forest were lower than other vegetation types, which disclosed that riparian forest distributed in the manner of smaller patches in the whole landscape. The value of mean patch shape, fractal dimension index, and edge density index of riparian forest were higher than other vegetation types, which indicated that riparian forest had more complex patch shape. All the pattern indices demonstrated that riparian forest was the most fragmented type in Irtysh River Basin, which was mainly due to that the riparian forest haven experienced high intensity and frequency of human disturbance since it had the highest biodiversity and most abundant natural resources in the landscape of Irtysh River Basin. The landscape diversity indices showed that the patch area distributed rather unevenly, the patch number distributed more evenly, however.