Aeolian desertification is a kind of land degradation that is characterized by aeolian activity, resulting from the responses of land ecosystems to climate change and anthropogenic disturbances. The source areas of the Yangtze and Yellow Rivers are typical regions of China’s Tibetan Plateau affected by aeolian desertification. We assessed the vulnerability of these areas to aeolian desertification by combining remote sensing with geographical information system technologies. We developed an assessment model with eight indicators, whose weights were determined by the analytical hierarchy process. Employing this model, we analyzed the spatial distribution of vulnerability to aeolian desertification and its changes from 2000 to 2010, and discuss the implications. Overall, low-vulnerability land was the most widespread, accounting for 64%, 62%, and 71% of the total study area in 2000, 2005, and 2010, respectively. The degree of vulnerability showed regional differences. In the source areas of the Yangtze River, land with high or very high vulnerability accounted for 17.4% of this sub-region in 2010, versus 2.6% in the source areas of the Yellow River. In the Zoige Basin, almost all of the land had very low to low vulnerability. To understand the change in vulnerability to aeolian desertification, we calculated an integrated vulnerability index (IVI). This analysis indicated that the vulnerability to aeolian desertification increased from 2000 to 2005 (IVI increased from 2.1709 to 2.2463), and decreased from 2005 to 2010 (IVI decreased from 2.2463 to 2.0057). Increasing regional temperatures appear to be primarily responsible for the change in vulnerability to aeolian desertification throughout the region. The effects of other factors (climatic variation and human activities) differed among the various sub-regions. The implementation of the ecological restoration project has achieved a noticeable effect since 2005. Our results provide empirical support for effort to protect the ecology of this ecologically fragile region.
The source areas of the Yangtze and Yellow Rivers were determined to be national nature reserve areas in 2003, and preparation for ecology restoration and construction in the study area was completed at the same time. In 2005, protection measures, including returning grazing land to grassland, were formally carried out.... Moreover, in the Zoige Basin, a number of political measures were initiated in the 1990s to slow desertification, but the countermeasures of grazing prohibition, enclosures, and paving straw checkerboard barriers were not implemented until around 2005.
Climate change impacts | Effect of Nbs on CCI | Effect measures |
---|---|---|
Desertification | Positive | desertification vulnerability index (DVI) -The sum of exposure, sensitivity, and adaptive capacity (see table 1) |
The source areas of the Yangtze River lie between 32 ̋311N and 35 ̋461N latitude and between 90 ̋331E and 97 ̋441E longitude (Figure 1a). The highest altitude is 6519 m, the lowest altitude is 3350 m, and the mean altitude is 4754 m. This region covers an area of 1.42 ˆ 105 km2 and includes five counties (Qumalai, Zhiduo, Chengduo, Zaduo, and Yushu of Qinghai Province) as well as Tanggula township of Golmud City. The region is bounded by the Kunlun Mountains to the north, and by the Tanggula Mountains to the south.