Journal of Geographical Sciences ›› 2007, Vol. 17 ›› Issue (2): 165-174.doi: 10.1007/s11442-007-0165-z

• Climate and Environmental Change • Previous Articles     Next Articles

The classification and assessment of freeze-thaw erosion in Tibet

ZHANG Jianguo1, LIU Shuzhen2, YANG Siquan3   

  1. 1. School of Geography, Nantong University, Nantong 226007, China|
    2. Institute of Mountain Hazards and Environment, CAS, Chengdu 610041, China|
    3. National Disaster Reduction Center, MCA, Beijing 100053, China
  • Received:2007-02-08 Revised:2007-03-16 Online:2007-06-25 Published:2007-06-25
  • Supported by:

    Key Basic Research Project of China, No.2004CCA03600

Abstract:

Freeze-thaw erosion is the third largest soil erosion type after water erosion and wind erosion. Restricted by many factors, few researches on freeze-thaw erosion have so far been done at home and abroad, especially those on the assessment method of freeze-thaw erosion. Based on the comprehensive analysis of impact factors of free-thaw erosion, this paper chooses six indexes, including the annual temperature range, annual precipitation, slope, aspect, vegetation and soil, to build the model for relative classification of freeze-thaw erosion using weighted and additive methods, and realizes the relative classification of the freeze-thaw erosion in Tibet with the support of GIS software. Then a synthetic assessment of freeze-thaw erosion in Tibet has been carried out according to the relative classification result. The result shows that the distribution of freeze-thaw eroded area is very extensive in Tibet, accounting for 55.3% of the total local land area; the spatial differentiation of freeze-thaw erosion with different intensities is obvious; and the difference in distribution among different regions is also obvious.

Key words: Tibet, freeze-thaw erosion, GIS, classification and assessment