基于GIS的醴陵市景观格局动态变化研究

Dynamics Changes of Landscape Pattern of Liling City Based on GIS

利用2003年和2009年两期的Landsat TM/ETM＋遥感影像资料,结合GIS与景观生态学分析方法,将湖南省醴陵市土地利用方式划分为水田、旱地、园地、林地、城乡居民工矿用地、水域和未利用地7种景观类型,在ERDAS 8.6、Arc GIS 9.0和Microsoft Office Excel 2003软件支持下,从斑块面积、斑块数目、斑块密度、面缘比、Shannon景观多样性、优势度、均匀度等方面对醴陵市景观空间分布和结构特征进行了系统分析。结果表明,在2003~2009年间,醴陵市土地景观空间格局发生了显著变化,水田、旱地、园地、未利用地的面积有所减少,林地、城乡居民工矿用地、水域则在增加;从景观组分来看,斑块面积、斑块数目、斑块密度、面缘比、Shannon景观多样性、优势度、均匀度等均发生了明显的变化;从土地利用变化来看,不同土地利用类型变化速度各异,土地利用景观格局向着林地、城乡居民工矿用地与水域发展,景观破碎化程度加剧。人口增加、产业结构调整、城镇扩张、退耕还林政策的实施以及农业开发等活动是醴陵市景观格局演变的主要驱动因素。

Based on the Landsat TM/ETM＋ remote sensing data collected in the year of 2003 and 2009, and combining GIS with analytical methods of landscape ecology, the changes of land use/cover and landscape pattern of Liling city of Hunan province from 2003 to 2009 were studied. The landuse was classified into 7 types including paddy field, dry land, garden land, forest land, urban and rural residents, water land and unused land. The dynamics changes of landscape pattern of Liling city during 2003-2009 were systematically analyzed using the indices including patch area, patch number, patch density, area-perimeter fractal dimension, Shannon＇s diversity index, dominance and evenness to describe the changes in the quantity, spatial pattern of landscape elements with the support of ERDAS 8.6, Arc GIS 9.0 and Microsoft Office Excel 2003. The results showed that the landscape spatial pattern of Liling city had significant changes. Paddy field, dry land, garden land and unused land decreased while forest land, urban and rural residents, water land increased. At the level of landscape, patch area, patch number, patch density, area-perimeter fraetal dimension, Shannon＇s diversity index, dominance, evenness degree changed greatly. From the view of landscape types, different types of land use changed at different rates. The landscape developed to forest land, urban and rural residents and water land. Fragmentation of landscape increased. The implementation of policy of converting of farmland into forest land, increase of population, restructuring of industry, urban sprawl and agricultural activities were the main driving factors of the dynamic changes of landscape pattern in Liling city.