以1989年、1999年、2009年3期6景LandsatTM/ETM遥感影像为数据源,采用分层分类、监督分类与人工目视纠错相结合的方法对巢湖流域土地利用景观类型信息进行分层提取,运用Fragstats软件分析流域内20a间的景观格局变化,并研究其变化规律特征。结果表明:(1)巢湖流域1989~2009年建设用地增加38380h㎡,动态度高达18%,耕地面积减少34230h㎡,水体面积相对稳定,常绿林地增加40350h㎡,落叶林地减少6760h㎡,城镇建设用地的增加主要来源于农田和其他用地类型的转入。(2)近20a间流域斑块个数(NP)与斑块密度(PD)呈现直线下降,下降率均约为22%,块形状指数(LSI)的下降率更加迅速,约为28%,最大斑块指数(LPI)则表现出V字变化规律,聚合度指数(AI)呈稳步上升,说明景观变化受人类活动的影响越来越大。(3)从景观类型上看,2009年的斑块个数(NP)和斑块密度(PD)比1989年下降了近1/2,常绿林和其他用地的变化是主要因素;块形状指数(LSI)降低则是受农田和其他用地的影响所致。(4)伴随巢湖流域行政格局改变和经济快速发展,流域土地利用将发生巨大改变。研究成果将是新格局发展的背景记录,为今后巢湖流域社会经济发展规划提供科学的理论支撑。
.Based on the analysis of land use data obtained from six Landsat TM and ETM images in the years of 1989,1999 and 2009,this paper took advantage of the hierarchical classification method and the method which is combined with the supervised classification and the artificial visual interpretation to extract landscape class information of land use in the Chaohu Lake Basin.Further more,the Fragstats software was utilized to analyze the changes of landscape pattern during 20 years and to study its change regulation and variation characteristics. The results are as follows. (1) From 1989 to 2009, the area of construction land in the Chaohu Lake Basin increased 38 380 hm2 and the dynamic degree was up to 18%,while the cultivated area reduced 34 230 h㎡.The area of water was relatively stable.The area of evergreen forest increased 40 350 h㎡, and on the other hand, the area of deciduous woodland decreased 6 760 h㎡.Besides, the increase area of urban construction land was major derived from the change of farm land and other types of land use.(2) The numbers of plaque (NP) and the patch density (PD) made a linear reduction during 20 years,and all the decline rates were about 22%.With respect to the block shape index (LSI),it decreased quickly as its rate was about 28 %.Moreover,the largest patch index (LPI) showed that the change rule of V shaped,and the aggregation index (AI) was steady rising, so that it illustrated that the landscape change was affected more and more by human activities. (3) In terms of the types of landscape, the numbers of plaque (NP) and the patch density (PD) showed a decreasing trend from 1989 to 2009,the decline extent of which was nearly one half.The principal factors to make the numbers of plaque (NP) as well as the patch density (PD) descend were evergreen forest and other land.At the same time,the reduction of block shape index (LSI) was caused by farm land and other land. (4) With the changes of administrative division in the Chaohu