A quantitative research on land use dynamic during 1986~2000 of the west of Songnen Plain has been done

based on the spatial cartographic data base system. According to the analysis

the land use/cover in the west of Songnen Plain have undergone dramatic changes. The area of farmland and salinized land increased rapidly while that of grassland

woodland

and water area decreased significantly in recent 15 years. The dominant land use change types were the conversion of grassland and woodland into farmland

dryland into paddy field and grassland into salinized land. Land use/cover change in this area was closely related to climate fluctuation

rapid growth of population and underdeveloped economic position

wherein social-economic factors were more important.