DESERTIFICATION DEVELOPMENT AND REGIONAL CLIMATIC CHANGE IN NORTHEAST CHINA IN THE 1990S

By using of a '3S' system of earth resource satellite remote sensing information precessing and application for Jilin Prov ince,we have inver sed and compared Landsat T M data in the 1980s and the late 1990s,and find that the ecological environment in the west of Northeast China is becoming deterioration.The main features are:desert ification(salinization and desertization)area is developing and extending along meridional direction,approaches and threats Songliao Plain in the central part of Jilin Province-one of the most important commoditygrain bases in China from three sides,and discarded farm lands in Xinkai River and ji Moron River Valleys in Jirem League increase clearly.By analysis and comparing the mean temperature and annual and season rainfall during two 8 years 1981-1988 and 1989-1996,we discover that the annual mean temperature increases by more than 0.7℃ in the whole Northeast which is the third high-value area of temperature increase in Eurasia of Northern Hemisphere,the hig hest 1.0℃ in the northzone(48-54°N) of the west Northeast,the next 0.9℃ in the middlezone(44-48°N),the middle zone with annual mean rainfall decrease 30mm and rainfall interannual relative variability 20%-30% is a sensitive belt of rainfall,the southzone(42-44°N) with a year mean increase 44mm is a clear increase belt of rainfall,and rainfall in the northzone increases slightly with a annual mean increase 15mm.The research indicates that the regional response to global change and global warming in the 1990s in the west of Northeast has two main features,i.e.desert ification development of land-cover type along meridonal direction and a warmingdr ying tendency of the regional climatic change.These are the main features of drought in the west of Northeast China.