Abstract:

According to a series of landscape indexes the sandy desert and sandy land were classified into four types as shifting, semi-shiftng, semi-fixed, and fixed. Through interpreting TM images in 2000, the database of sandy desert and sandy land of China was established at a scale of 1:100,000 by remote sensing and geographical system techniques. And based on analyzing the database, the following points can be concluded.　(1) There were 38,734,730 ha of gravel Gobi and 124,230,119 ha of sandy sesert and sandy land in China in 2000. (2) The shifting type occupied 41.46% of the total sandy desert and sandy land in China, the semi-shifting 24.21%, the semi-fixed 20.38%, and fixed only 13.94%.　(3) Sandy desert and sandy land were distributed in different bioclimatic zones of 719 counties or cities in 28 provinces or autonomous regions, where 62.33% were distributed in extremely arid zone with shifting and semi-shifting types in domination; 21.94% distrbuted in arid zone with fixed and semi-fixed types exceeding the sum of shifting and semi-shifting types; 8.78% of them distributed in semi-arid zone having fixed and semi-fixed also as main types; 6.78% distributed in semi-humid zone with greatest part being fixed and semi-fixed types; and 0.15% of them distributed in humid zone, having fixed and semi-fixed as the main types with shifting type exceeding semi-shifting and semi-fixed types.

Key words: sandy desert, sandy land, gravel Gobi, remote sensing analysis