Abstract:
Climate change is a main control factor for the formation and development of desertification in north China. The climate pattern established during the up lift of the Qinghai-Tibet plateau and the descent of in land basins basically built up the distribution of desertified land in north China since Cenozoc. The climate in inland basins is arid,central China plateau is featured by semi-arid climate prominently con-trolled by the East A sian monsoon system while east China is dominated by worm and humid climate influ-enced by summerwind. The Quaternary climate variations have controlled desert expansion and reverse. Since last interglaciation, on going climate oscillations characterized by a 1 500 a cycle have dominated desertification in north China. Desertification at about 10,000 aBP, 8,000 aBP, 5,500 aBP, 4,000 aBP, 3,000 aBP and 1,500 aBP respectively corresponds to Numbers 7,5,4,3,2,and 1 floatingice events occurring in the North Atlantic Ocean, identical to the global climate fluctuation events. Cyclic climate changes at decade scale affect desertification to some extent, at leastin some sensitive zoneswhere theecological environment is fragile. Cycliic climate oscillations at annual scale such as 6.7a and 3.38a may be important to dust storm. Furthermore, human activities are responsible for desertification expansion in many areas during last 150 years.