1976-2008年黄河三角洲湿地变化的遥感监测

Monitoring Wetland Changes in Yellow River Delta by Remote Sensing during 1976-2008

基于景观生态学原理,借助遥感(RS)和地理信息系统(GIS)等技术手段,对1976、1986、2000和2008年的遥感数据进行了处理和分析;探讨了1976年以来现代黄河三角洲湿地的变化特征。结果表明:自1976年以来,现代黄河三角洲湿地总面积呈下降趋势,1976-2008年湿地总面积减少了8.5%,其中自然湿地面积呈显著减少变化,1976-2008年减少了44.5%;现代黄河三角洲典型湿地类型——芦苇湿地的面积也呈减少趋势,面积减少了23.0%;与此相反,人工湿地的面积大幅度增加,1976-2008年增加了70.7倍。现代黄河三角洲湿地1976、1986、2000和2008年的分形维数分别为1.4636、1.4858、1.5046和1.4841,这表明该区域内湿地受到人为因素影响较大。现代黄河三角洲芦苇湿地分布质心呈逐渐向河口方向偏移特征,其中1976-1986年芦苇湿地分布质心偏移较大,1986-2000间次之,2000-2008年基本没有变化。

Based on the landscape ecology principles, remote sensing （RS）, geographical information systems （GIS） and other technical means, the remote sensing images of 1976, 1986, 2000 and 2008 are processed and analyzed. The results show that the total area of wetlands decreased by 8.5% in the modem Yellow River Delta from 1976 to 2008. The area of natural wetlands decreased by 44.5% from 1976 to 2008. The area of reed wet- land decreased greatly too. From 1976 to 2008, it decreased to 23.0%. On the contrary, the area of constructed wetlands increased significantly, and from 1976 to 2008 it increased by 70.7 times. The fractal dimensions of wetlands in 1976, 1986, 2000 and 2008 were 1.4636, 1.4858, 1.5046 and 1.4841, respectively. It means that the wetlands in the modem Yellow River dalta were greatly affected by human disturbance. The distribution centroid of reed wetlands has moved towards the estuary direction. It moved farthest from 1976 to 1986, followed by the period from 1986 to 2000. It was basically unchanged from 2000 to 2008.