1988—2001年重庆市主城区植被的时空变化

利用Landsat遥感影像,分析了重庆市主城区1988、1993和2001年共3期植被的时空动态变化。结果表明:1988—2001年主城区的植被面积呈加速下降趋势,植被斑块的破碎程度逐渐增大,空间分布越来越分散,其中1993—2001年的变化比1988—1993年的变化更明显;对3期影像进行叠加,得到了8类变化轨迹的斑块;通过分析不同变化轨迹的斑块的空间格局和空间作用,揭示出植被的时空动态变化特征;3期中均为植被和非植被的轨迹所对应的斑块自相关程度较高;其余6类变化轨迹所包含的斑块自相关程度低,并在1988—2001年经历了植被与非植被的转变。

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.