基于遥感和GIS的上海市滩涂湿地资源近期变化分析

利用多期Landsat-5 TM影像,结合植被分带信息、地物波谱特征和实地调查数据,提取上海地区滩涂湿地分布及其覆盖信息;在ArcGIS软件支持下,综合多期遥感影像解译结果和相应时段的水下地形信息,对上海市滩涂湿地空间分布及其变化进行分析。结果表明,近15年来上海市滩涂围垦量在不断增加;尽管滩涂湿地仍在继续淤涨,但淤涨速度明显减缓,且慢于围垦速度,这导致中高潮滩涂面积不断减少。

Shanghai Estuarine and Coastal Wetlands Change Analysis Based on Remote Sensing and GIS

Taking into consideration of the information of vegetation zoning,reflectance spectral signatures of land cover and field investigations,the estuarine and coastal wetland distribution information of Shanghai region is extracted from multiple Landsat-5 TM images on the basis of the determination of pixel threshold for land cover classification.With ArcGIS,spatial data of the wetlands both of tidal flat and terrain beneath water are integrated.Therefore the wetlands distribution in the past and present and changes are analyzed.Results show that the reclamation of the wetlands kept an increased trend for the past 15 years.Although the tidal flat still grows,the deposition speed obviously decreases and it does not catch up with the reclamation activities.Thus the size of wetlands of middle to high elevation has a decreasing tendency.