基于TM影像的湿地格局变化空间分析--以洪湖市为例

Spatial analysis of wetland changes based on the TM image——a case study in Honghu city

利用图像处理技术对1991年、1995年、2001年的TM影像数据进行处理以提取洪湖市湿地类型,并通过GIS空间分析计算洪湖市各类型湿地变化的紧凑性指数和熵.结果表明各类湿地均有不同程度的变化,湖泊、河流的面积减小,并且湖泊的紧凑性指数较大,反映出湖泊减少的速率很快.3年间各类型湿地的平均熵值有所减小,这说明洪湖市湿地正朝着集中化的分布方式发展,这是人为干预湿地所造成的结果.

On the use of image processing technology, the 1991, 1995, 2001 TM image data are processed to extract the wetlands in Honghu city, and through the GIS spatial analysis to calculate the compact index and entropy of the various types of wetland change in Honghu city. The results show that all types of wetlands have different degree of change, the lake and river decrease, and the compact index of the lake is higher, reflects the reduction rate is rapidly. The average entropy of various types of wetland has reduced in these three years, which reflects the Honghu city wetlands are developing into the centralized distribution model, and it is the result of human intervention.