1985年以来太湖流域耕地变化与粮食生产研究

太湖流域经济与城市化过程持续加速而耕地流失及粮食供需形势日趋严峻。基于最小人均耕地面积（Smin）和耕地压力指数（K）模型及其分析与预测，定量研究流域耕地变化和粮食生产特征及趋势。结果表明：1985年以来，流域人口不断增长，耕地面积随人均GDP增长呈显著的对数型减少，粮食总产波动降低；Smin和K值经过1985～1997年的平缓波动后持续上升，2003年之后又有所降低。区域分析结果揭示了整个流域耕地压力凸显的现实；未来10 a耕地生产力提高促使Smin逐年减小，但Sa递减速度较快，K值上升明显；两种预测情景表明降低粮食自给率一定程度上缓解了区域耕地压力，但口粮供给还有缺口，由此提出转变经济发展方式、创新耕地利用和粮食生产的调控机制等相关建议

RESEARCH OF CROP LAND CHANGE AND GRAIN PRODUCTION IN TAIHU LAKE BASIN SINCE 1985

With the population increasing and rapid urbanization development,the economy and urbanization process continued to accelerate in Taihu Lake Basin.The cropland resources were fast dwindling and the supply and demand conflict of food was intensifying,while the demand for food is increasing rapidly.Based on the analysis and forecasting of minimum cropland acreage per capita and cropland pressure index model,the paper quantitatively analyzed the dynamic changes in cropland acreage and grain production respectively of Taihu Lake Basin.It was found that the population presented swift growth and cropland area kept on decreasing with the growth of GDP per capita since 1985. Simultaneously,the grain production showed instability and a tendency to decline.In general,the minimum cropland acreage per capita and cropland pressure index were obvious temporal fluctuation between 1985 and 1997,but displayed an increasing trend from 1997 to 2003 and a reduction after 2003.The analysis of different regions reveals the reality that the cropland pressure was obvious in the whole study area.The minimum cropland acreage per capita would be a continuous decrease with increasing in the arable land productivity in the next 10 years.Because of the rapid reduction in the cropland acreage per capita,the cropland pressure index will increase significantly.Two self sufficiency rate scenario shows that the decreasing of the food self sufficiency rate to some extent can alleviate cropland pressure at the regional scale. However,there will be a supply gap of grain for eating in the further. In view of the results of analysis and prediction,countermeasures for reduction of cropland pressure and guarantee the balance of food supply were proposed