STUDY ON THE SPATIAL PATTERNS OF LAND-USE CHANGE AND ANALYSES OF DRIVING FORCES IN NORTHEASTERN CHINA DURING 1990-2000

Land-use change is an important aspect of global environment change. It is, in a sense, the direct resultof human activities influencing our physical environment. Supported by the dynamic serving system of national resources,including both the environment database and GIS technology, this paper analyzed the land-use change in northeastern Chi-na in the past ten years (1990 -2000). It divides northeastern China into five land-use zones based on the dynamic de-gree (DD) of land-use: woodland/grassland - arable land conversion zone, dry land - paddy field conversion zone, ur-ban expansion zone, interlocked zone of farming and pasturing, and reclamation and abandoned zone. In the past tenyears, land-use change of northeastern China can be generalized as follows: increase of cropland area was obvious, pad-dy field and dry land increased by 74. 9 and 276. 0 thousand ha respectively; urban area expanded rapidly, area of townand rural residence increased by 76. 8 thousand ha; area of forest and grassland decreased sharply with the amount of1399. 0 and 1521.3 thousand ha respectively; area of water body and unused land increased by 148.4 and 513.9 thou-sand ha respectively. Besides a comprehensive analysis of the spatial patterns of land use, this paper also discusses thedriving forces in each land-use dynamic zones. The study shows that some key biophysical factors affect conspicuously theconversion of different land-use types. In this paper, the relationships between land-use conversion and DEM, accumulat-ed temperature(≥10℃) and precipitation were analysed and represented. We conclude that the land-use changes in north-east China resulted from the change of macro social and economic factors and local physical elements. Rapid populationgrowth and management changes, in some sense, can explain the shaping of woodland/grassland-cropland conversionzone. The conversion from dry land to paddy field in the dry land - paddy field conversion zone, apart from the physicalelements change promoting the expansion of paddy field, results from two reasons: one is that the implementation of mar-ket-economy in China has given farmers the right to decide what they plant and how they plant their crops, the other fac-tor is originated partially from the change of dietary habit with the social and economic development The conversion frompaddy field to dry land is caused primarily by the shortfall of irrigation water, which in turnis caused by poor water alloca-tion managed by local governments. The shaping of the reclamation and abandoned zone is partially due to the lack of environ-ment protection consciousness among pioneer settlers. The reason for the conversion from grassland to cropland is the relative-ly higher profits of farming than that of pasturing in the interlocked zone of farming and pasturing. In northeastern China,the rapid expansion of built-up areas results from two factors: the first is its small number of towns; the second comesfrom the huge potential for expansion of existing towns and cities. It is noticeable that urban expansion in the northeasternChina is characterized by gentle topographic relief and low population density. Physiognomy, transportation and economyexert great influences on the urban expansion.