The Desertification Dynamics in Ordos from 2000 to 2010and Their Relationship with Climate Change and Human Activities
Ordos is one of the regions that seriously suffered from desertification in China.Carrying out the research on the desertification dynamics monitoring and its relationship with driving forces in Ordos has significance for understanding the process of desertification,making and evaluating the policies for desertification rehabilitation.In this paper,based on using the MODIS data to monitor the desertification dynamics in Ordos from 2000 to 2010,the changing trends of net primary productivity due to climate change and human activities for the lands experienced desertification reversion and expansion is analyzed,and the desertification dynamics in Ordos from 2000 to 2010 and their relationship with climate change and human activities are quantitatively assessed.It is found that the area of desertification land in Ordos did not changed obviously from 2000 to 2010,but the degree of desertification reversed significantly,and area of lands experienced desertification reversion reached 47 057 km2(accounting for 54.2% of the total area of Ordos),which was almost three times higher than that of desertification expansion.Climate change was the dominated factor that induced the desertification reversion from 2000 to 2010,which almost could be attributed to the increasing precipitation and the decreasing of wind speed in spring from 2000 to 2010.Also the implement of ecological protection policies,such as rangeland enclosure and grain for green and its' coupling with good climate condition,accelerated the desertification reversion.Human activities was the dominant factor that induced the desertification expansion from 2000 to 2010,which mainly attributed to the implementation of those ecological protection policies ineffective and the environment damage due to development of energy and mining industries,and the lands with desertification expansion totally induced by human activities mainly distributed in the north of Ordos.