Dynamics of aeolian sandy land in the Yarlung Zangbo River basin of Tibet, China from 1975 to 2008

Aeolian sandy land in the Yarlung Zangbo River basin has attracted the attention of many researchers. However, its dynamics as well as its relevance to various factors has rarely been reported with integrated studies. In this paper, spatio-temporal dynamics of the aeolian sandy land in the basin was studied by interpreting Landsat images acquired from 1975, 1990, 2000, and 2008 with the help of geographic information system (GIS) technology. Spatially, the results showed a decreasing trend from west to east, which is from the Maquanhe wide valley in the headwater area to the middle and lower reaches of the river basin. Temporally, aeolian sandy lands in the basin showed a slow increasing trend, with an increase of 10.5% during the 1975–2008 period, spreading most quickly during the period of 1990–1999. The factors related to dynamics of aeolian sandy land were analyzed from the perspectives of two driving factors, climate changes and human activities. The climate-dominated natural factors are the internal driving forces for the development of aeolian sandy lands, and the human factors are the external driving forces responsible for the increase of the aeolian sandy land area.