Abstract: Based on the soil temperature and meteorological data from observation station, characteristics of soil temperature variation are analyzed in the Badain Jaran Desert Hinterland. The results are as follows: (1) The diurnal variations of soil and air temperature are significant, and the highest temperature appears at 17:00, which is about 2 hours later comparing with eastern region. The variation of soil temperature is nearly equal to air temperature, but clearly lags behind air temperature and solar radiation in different seasons; (2) The soil temperature dips to 0 ℃ from late November to February. When soil depth is below 60 cm, soil temperature keeps above 0 ℃ the whole year, and the variation range of soil temperature decreases with the increase of soildepth; (3) The variation of soil temperature is determined by solar radiation directly. The environmental factors which affects the soil temperature are seasonal. In winter, spring and autumn the major factors are air temperature, solar radiation and precipitation, while the velocity of wind is another significant factor in summer. Air temperature and solar radiation have continuity effect on soil temperature among these factors, while precipitation causes the sudden declines of soil temperature directly.

Key words: Badain Jaran Desert, soil temperature, soil depth, climate factor