洪泽湖区土地利用/覆盖变化分析

利用1973年、1984年和2006年3期Landsat卫星遥感图像，分别对校正处理后的3期图像进行缨帽变换，并利用亮度、绿度和湿度这3个分量的差值运算进行信息复合。然后利用变化向量分析法确定复合图像中的变化和非变化像元之间的变化强度阈值。最后利用阈值分割和掩膜技术，对3期图像进行土地利用/覆盖变化监测。研究表明，近33年来洪泽湖区土地利用结构发生根本性改变：天然湿地面积大幅度缩减，1973年~1984年间减少了200.55km2，1984年~2006年间减少了357.04km2，主要表现为敞水区和湿地植被面积的减少，养殖场、农田面积显著增加，城镇用地略有增加。本文研究表明基于缨帽变换并结合差值运算方法和变化向量分析法实现土地利用/覆盖变化监测的可行性。

Analysis on Land Use/Cover Change in Hongze Lake

In this paper,three Landsat satellite images acquired in 1973,1984 and 2006 were chosen.Tasseled Cap transformation was carried out on three corrected images respectively.Components of brightness,greenness and wetness were then selected to compute the differences and composite information.Then the method of change vector analysis was used to determine the threshold of the composite image between change and non change pixels.Finally,thresholding of change vector analysis and mask technology were used to detect land use/cover change in the three images.The results show that there is a significant change in the structure of land use /cover in Hongze Lake over the past 33 years.From 1973 to 1984,it reduced by 200.55km2 and from 1984 to 2006,it reduced by 357.04km2.The decreased types are mainly the open area and the wetland vegetation.The areas of aquacultures and rice paddy increased obviously,and that of urban land also increased slightly.The results also show that the combination of Tasseled Cap transformation,computing the difference and change vector analysis make it applicable for change detection of land use/cover.