Change trends for desertified lands in the Horqin Sandy Land at the beginning of the twenty-first century

摘要

The dynamics of desertification in the Horqin Sandy Land between 2000 and 2005 were analyzed using Landsat TM/ETM images and the data-processing function of geographical information software. The results showed that the extent of desertified land decreased at a rate of slightly more than 0.1 km~2 year~(-1), from 22,423.1 km~2 in 2000 to 22,422.4 km~2 in 2005, indicating that desertification has been controlled in this area and that desert areas may be approaching a steady state. The dynamics of desertification differed among land types. Desertification decreased most obviously in areas of previous desert land. The area in which desertification was ameliorated was higher than the area that underwent further degradation, but non-desertified land (113.3 km~2) deteriorated at a rate of 22.7 km~2 year~(-1) during this period. This significant change requires careful attention by managers in the study area.