Types and temporal-spatial change of desertized land in the Yulin area, northern Shaanxi

Abstract: According to the results of TM remote sensing image interpretation of two time phases in 1987 and 1999 and using the space analysis and mathematic statistics of the geographic information system, the paper analyzes the degree of land desertization and features of the temporal-spatial change of land desertization in the Yulin area, northern Shaanbei, in 1987-1999 and discusses the cause of land desertization. The analytic results indicate that since the late 1980s the process of the land desertization of the area as a whole has tended to be stable and taken a more or less favorable turn. This mainly benefits from the policies of active and effective control of land desertization implemented by the local government. The fragile ecological environment, arid climate and plenty of wind are main natural driving factors for land desertization, while irrational human activities are a factor of inducing land desertization. Measures of active control and improvement can effectively control the process of desertization.