Landscape change and desertification development in the Mu Us Sandland, northern China

In order to document the status and causes of desertification development in the Mu Us Sandland located in the agro-pastoral transitional zone in northern China, we interpreted and analysed satellite images, historical maps, meteorological and socio-economic data to assess landscape change from the 1950s to the 1990s. During the intervening 35-year period, landscapes have changed significantly in this area. The shifting and semi-fixed sandy lands have increased by 540,915.3 and 399,302.2 ha, respectively, and now cover 44.53% and 21.44% of the area of the Mu Us Sandland, in the meantime the fixed sandy land has decreased by 572,130.6 ha and covers only 7.22% of the sandland. The rate of desertification in the middle and northwest, where there is only pasture, is much higher than that in the east and south, where farmland and pasture exist together. In most of the sandland, desertification has developed rapidly, while rehabilitation of vegetation has occurred only in marginal areas in the east and south. The main causes of desertification development in the Mu Us Sandland are intensified and irrational human activities, such as over-reclaiming, over-grazing and over-cutting. (C) 2002 Elsevier Science Ltd.