Abstract:

Based on RS and GIS technologies, the temporal and spatial dynamics of sandy desertification in China under climate disturbance were studied by pixel based grey correlation method during the recent 32 years. The data used in this paper incorporated MSS imageries in 1975, ETM imageries in 2000, CBERS imageries in 2007, temperature，and precipitation data. The results showed that the area and degree of sandy desertification reduced from 2000 to 2007, but, still showed slightly increasing trend from 1975 to 2007. Over the past 32 years, the whole area increased 6 179.8 km², and the greatest increased area occurred in heavy desertification. With the application in Inner Mongolia and Xinjiang, the grey correlation analysis in China indicated that, compared with precipitation(0.884, 0.882), temperature played a more important role (0.973, 0.976) in sandy desertification change. Under the disturbance of climate factors, the general tendency of sandy desertification was positively correlated with temperature and negatively related to precipitation. The tendency was more distinct in the west of Gansu and Shaanxi. The most obvious area concentrated in the north and east of Xinjiang, and the north of Tibet.

Key words: sandy desertification, climate change, remote sensing, geographic information systems, spatial correlation analysis