快速城市化进程中城市扩张对景观格局分异特征的影响

Impacts of urban expansion on spatio-temporal variation of landscape patterns during rapid urbanization:a case study of Kunshan city

在中国快速城市化背景下,大部分研究仅是单一的利用景观指数分析城市景观格局,往往只侧重于对景观斑块或格局的几何特征进行简单分析和描述,忽略了城市扩张与城乡景观格局动态变化过程之间的内部联系,研究城市扩张与城乡景观格局动态变化过程之间的内部联系对揭示城市化规律有着重要意义。文章以江苏省昆山市(县)范围为研究对象,基于全市1985—2008年间多期TM影像图,在采用遥感与地理信息系统相结合的技术方法获取昆山市景观格局动态变化以及相关景观生态学指数分析的基础上,探讨城市扩张对城乡景观格局的影响。结果表明:23年间自然景观类型的面积基本保持不变;人工景观面积显著增涨了4倍。斑块密度、景观斑块数量破碎度指数受人工景观类型影响基本呈上升趋势;斑块密度、景观破碎度、最大斑块、边缘密度等指数与建设用地增长之间存在明显相关性,表明城市扩张是城乡景观格局特征变化的重要驱动力。

With the process of rapid urbanization in China,most of studies used single index to analyze the landscape pattern,and only focused on the landscape characteristics or a simple geometric pattern analysis,but ignored the internal relations in dynamic change be-tween landscape pattern and urban expansion.There is an important significance that the study of the internal relations between the changes of urban expansion and urban landscape pattern.In this paper,as Kunshan city to be the subject,based on the 1985-2008 TM maps,using remote sensing and geographic information systems technology,we analyzed the changes of landscape pattern,and the cor-relation between a variety of landscape ecological indicators and built-up expansion.The results showed that the areas of natural land-scape remained unchanged during the 23 years and artificial landscape areas increased by 4 times significantly.Patch density,landscape fragmentation indexes by the artificial landscape turned upward;PD,PN,LPI,ED,FI and the built-up expansion were significant corre-lation,which indicated that urban expansion was a key driver for the change of landscape pattern characteristics.