利用景观梯度法分析张家港市城市景观变化

Gradient Analysis of Landscape Change of Zhangjiagang

在遥感与GIS技术平台的支持下,利用景观格局梯度法分析了张家港市各土地利用类型的景观格局及其时空分布特征。研究结果表明,2002—2006年,张家港市城市景观格局总体变化明显,城镇用地增长22.10%,农业用地则减少14.96%。在空间上,呈现出城市—城乡交错带—农业区的变化特征;在时间上,整体样带体现出斑块密度升高、聚合度降低、最大斑块指数下降的特点。城市景观在类型水平上的梯度变化存在着较大差异,水域和道路变化很小,而农业用地、城镇用地和绿地变化幅度较大。将景观格局指数和梯度分析相结合,能够较全面地反映城市景观格局与结构的变化特点。

With the aid of remote sensing and GIS technology,landscape patterns of various types of land use and their tempo-spatial distribution was studied through landscape pattern gradient analysis.Results show that during the years of 2002-2006,the overall landscape pattern of the city changed significantly,with urban land increased by 22.10%,while farm land decreased by 14.96%.Spatially,the present landscape features a gradient of urban area-rural-urban fringe-countryside,and temporally in time,the entire transect belt increased in patch density,but decreased in polymerization degree and the max patch index.At the type level,the gradient of urban landscape varied sharply;changes in water surface and roads were small,while changes in farmland,urban land and green land quite great in amplitude.The gradient analysis combined with landscape pattern indices can quite completely reflect characteristics of the changes in urban landscape pattern and structure.