土地是支撑区域发展最为基础的自然资源,保持一定数量的耕地是人类赖以生存和发展的基础。土地利用与土地覆被变化 (LUCC) 既受自然因素的制约,又受人文因素的强烈影响,是最能表达区域人－地关系状况的地理要素。因而不仅成为自然地理学研究的重点,而且也是人文地理学关注的热点。近50年来长江三角洲地区耕地变化过程表明,耕地变化主要受政策、经济发展和人口增长等人文因素驱动。分析显示,长江三角洲耕地面积随人均GDP的增长呈良好的指数减少关系,人均GDP低于12 000元/人,经济增长占用耕地的压力较大;人均GDP超过30 000元/人时,这种压力将开始减缓。现阶段长江三角洲仍处于经济发展对耕地压力较大的发展阶段,但已较1998年前明显减轻,预估至2010年前后,该区经济增长对耕地压力将明显得到缓解。

Land is the basic natural resource sustaining regional economic development, mantaining adequate cropland area is the foundation of human subsistence and development. Land Use and Land Cover Change (LUCC) is affected not only by physical factors, but also by human factors, so LUCC is a geographical element expressing the relationship between human being and nature, and it has become the research hotspot of not only physical geography but also human geography. The research results of the change in cropland area in the Yangtze River Delta during the past 50 years show that, policy, economic development and population growth are the main driving forces for the decrease in cropland area; there are remarkable exponential correlations between the decrease in cropland area and the increase in per capita gross domestic product (GDP). While GDP per capita is below 12,000 RMB yuan, the economic growth has a great pressure on cropland area; while GDP per capita exceeds 30,000 RMB yuan, the pressure of economic growth on cropland will gradually mitigate. At present, the Yangtze River Delta is experiencing the period of the rapid decrease in cropland area caused by the economic development, although the decreasing rate is obviously below that of before 1998. It is estimated that the pressure of economic development on cropland area will gradually mitigate after the year 2010.