由于统计方面的原因,1949年以来中国耕地资源数量变化至今尚没有一个客观的描述。针对该问题,论文对1949～2003年不同时期不同来源的耕地数据系列进行分析,认为统计数据存在问题较多的时期为1960～1985年,并采用粮食产量对耕地面积进行了分时期的反演,对于1986～1996年间的耕地数量则按照全国土地利用详查统一到1996年的结果再进行反推,由此重新刻画建国以来中国耕地资源数量变化的趋势和特征,并结合不同时段耕地相关政策对耕地数量变化的驱动作用进行分析。结果表明,1949年以来中国耕地资源数量呈现波动性变化,但在1979年之前总体上是增加的,自20世纪80年代起呈现缓慢下滑,1999年后由于生态退耕等原因引起耕地数量迅速减少,由此导致的中国粮食安全问题与耕地安全问题值得关注。在经过一段快速的大规模生态退耕时期后,中国生态退耕速度将逐步趋缓,耕地安全与粮食安全将会成为影响中国耕地数量变化的主要问题,严格的耕地保护政策势必将贯彻下去,预计2010年后中国的耕地资源数量将趋于稳定。

Studies of cultivated land change in China have long been hampered by the lack of accurate and reliable data since 1949.By analyzing the cultivated land data from different sources in different phases after 1949,the paper considers the statistics with more errors happens during 1960-1985.According to the systematic data on land use gathered in the 1996 survey,based on reverse deduction of the cultivated land area from 1986 to 1996,and deduction of the cultivated land area from 1960 to 1985 by stages by employing yield of grain,this paper redescribed the actual changing trend and character of Chinese cultivated land and analyzed the driving force of the policy relative to cultivated land to cultivated land area change.The result indicated that the Chinese cultivated land amount has been fluctuating since the founding of New China in 1949.It increased as a whole before 1979,and decreased slowly since the 1980s.The cultivated land amount decreased rapidly after 1999 because of cultivated land conversion into land for ecological purpose,hence the problems of grain security and cultivated land security result from which need to be paid more attention to.In future,the pace of ecological cultivated land conversion will be slowed down gradually after a fast ecological rescue phase,the grain security and cultivated land security will become the main influencing factors which affect changes of Chinese cultivated land amount.With the strict implementation of cultivated land protecting policy,the Chinese cultivated land amount will keep steady after 2010.