The monitoring of land-cover change in western China from remote sensing data

摘要

There are serious environmental problems, such as deforestation, soil erosion, salinization, and desert encroachment in the western China, its natural conditions is very delicate. But little is known about change in this region. The remote sensing data and digital image processing techniques provide consistent, reliable and quantifiable regional scale land-cover for environmental change research. The objective of this study is analyzing the environment change in a year in western China by using remote sensing data. In this paper, three typical experiment sites, which are a desert and oasis area, a loess plateau area and the source area of the Yellow River, are selected for detail change analyses. The change of NDVI, land-cover classifications between 1980s and present are detected from the satellite data. The datasets of remote sensing include Landsat-TM, ETM, SPOT and ASTER, all of these image are normalized to 30 m resolution and same coordination system for change analyses. The results show that industry development, cultivated land increment, soil erosion, forest and grassland decrement are the main reason of environmental deterioration.