江苏沿海地区景观格局的生态风险研究

Study on Landscape Ecological Risk of the Coastal Areas of Jiangsu Province

以江苏省沿海地区为研究区,利用1989年、1995年和2009年3个时期的TM遥感影像为数据源,计算各风险小区的景观生态风险指数。利用GIS和地统计学方法,对研究区景观风险指数进行采样和空间插值,得到基于景观格局的生态风险分布图。运用相对指标法对景观生态风险指数进行分级,将研究区域划分为低生态风险区、较低生态风险区、中等生态风险区、较高生态风险区和高生态风险区5个等级。叠加不同时期的生态风险区划图层,利用土地覆被重心转移模型以分析景观生态风险的时空变化。结果表明:近20a来研究区生态风险主要以较高程度为主,处于低、较低生态风险程度的区域面积变化不大,空间分布也一直位于盐城市,高风险区区域面积增加较为显著,主要位于盐城市的滩涂。低生态风险区和高生态风险区偏移量较大,分别为116.6km和4.9km。

The ecological risk index was calculated by taking the coastal areas of Jiangsu Province as studying area,using the remote sensing images of Landsat TM in 1989,1995 and 2009as the main data sourced.Ecological risk maps were obtained by resampling and interpolation by GIS and geostatistics method.Based on its ecological risk maps,the study area was classified into five kinds of areas：extremely low,low,moderate,high and extremely high ecological risk areas by relative index method.And then the temporal and spatial dynamics of ecological risk were analyzed by overlying the ecological risk maps in different periods.The results show that：in recent 20 years,most of the study area had moderate ecological risk;the area with extremely low and low ecological risk had no obviouse change and mainly located in Yancheng City;the area of high ecological risk increased significantly and mainly distributed in the coastal beach of Yancheng City.The gravity shift distances of extremely low ecological risk and the high ecological risk were the greatest which were116.6km and 4.6km,respectively.