基于MODIS卫星影像的湖南省景观格局

Landscape Pattern of Hunan Province Based on MODIS Image

景观格局是由自然或人为形成的一系列大小、形状各异,排列不同的景观要素共同作用的结果.利用2005年MODIS卫星数据,经过一系列处理后得到湖南省景观图.利用决策树分类法将研究区分为5种景观类型:水、自然植被、耕地、城镇用地、其它用地.选取斑块数、斑块密度、破碎度、斑块分维数、多样性指数、优势度、均匀度、聚集度、分离度等景观指数,从斑块、斑块类型和景观3个层次上对研究区景观格局进行定量分析.结果表明:湖南省景观斑块共39357块,总面积为21.1984万km2;在5种景观类型中,植被和耕地是主要景观类型,占研究区总面积的88.38%;湖南省景观多样性程度低,且斑块空间形状简单.

A landscape pattern is the result of all landscape elements acting together, which are natural or arlificial of different size, shape and arrange. As a kind of quantification indices of a landscape pattern, landscape metrics concemrates highly the information of landscape, which reflects its characters such as structure makeup and spaceordonnance. Remote sensing, a way of studying landscape ecology, plays an increasingly important role in gaining a landscape image, especially under the rapid development of satellite remote sensing and computer technology. In this paper, a landscape image with 250-meter resolution of Hunan Province was produced from the MODIS data of 2005 after a series of processings. It was classified into 5 types, namely water, natural vegetation, farmland, residential land and other land, using decision tree method. Some landscape metrics, such as number of patches, patch density, fragmemation, fractal dimension index, diversity index, dominance,, evenness index, aggregation index and division, were chosen to analyze the landscape pattern of the study area from patch, class and landscape levels. The results show that： 1）there are 39,357 patches in Hunan Province, and the total area of the patches is 21. 198 4 square kilometers; 2）in the S kinds of landscape, natural vegetation and farmland are the main landscape patterns, which accounts for 88.38 % of the total area; and ,3）the landscape diversity of the province is low, and the space shape of the patches are very simple.