关键词: 沙漠化, 动态, 遥感监测, 中国北方

Abstract: The data of aeolian desertification lands status in different periods have been extracted through visual interpretation method based on Landsat MSS, TM/ETM images in 1975, 1990, 2000, 2005 and 2010 over the northern China areas. Hence, we analyzed the changing trend of aeolian desertification in northern China during the last 35 years, and have got some results as follows: (1) The area of aeolian desertification lands in northern China in 2010 are 37.59×104 km2, among which the slight grade accounts for 33.80%, the moderate grade for 22.84%, the severe grade for 22.16%, and the extremely severe grade for 21.21%. (2) From 1975 to 1990, the net increase area of land desertification area of northern China was 33 838.32 km2 with an increasing rate of 2 255.89 km2·a-1; the net area of land desertification lands being intensified was 33 279.28 km2; thus the net developing rate was 4 474.51 km2·a-1. From 1990 to 2000, the net increasing rate of land desertification area was 3 441.49 km2·a-1 and net developing rate was 5 370.06 km2·a-1. Since 2000, there was a recovering trend of land desertification lands in northern China. From 2000 to 2005, the net area decreasing rate was 1 635.28 km2·a-1, and the net reversion rate was 10 071.02 km2·a-1. From 2005 to 2010, the net area decreasing rate was 1 114.35 km2·a-1, and the net reversion rate was 7 552.21 km2·a-1. Changes of land desertification mainly occurred in the agro-pasture ecotone of semi-arid area.

Key words: desertification, dynamic change, remote sensing monitoring, northern China