Spatiotemporal change of vegetation distribution in central area of Chongqing City in 1988-2001

By using Landsat images, this paper analyzed the spatiotemporal change of vegetation distribution in the central area of Chongqing City in 1988, 1993 and 2001. The results indicated that from 1988 to 2001, the vegetation coverage in the study area decreased speedily, vegetation patches fragmentized gradually, and the distribution of the patches became more and more dispersive. The vegetation change was less distinct in the first phase (1988-1993) than in the second phase (1993-2001). The three periods' land covers were classified into two types (vegetation and non-vegetation), and the land cover images in the three periods were overlaid into one image which contained the patches with eight types of change trajectories. The spatial pattern of the trajectories could illuminate the spatiotemporal change of vegetation well. The non-vegetation and vegetation patches without changed trajectories in the three periods had high spatial autocorrelation, while the patches with other six types of change trajectories had low spatial autocorrelation, and suffered a complicated change from 1988 to 2001.