长江中下游地区耕地复种指数变化与国家粮食安全

The Relationship of Multiple Cropping Index of Arableland Change and National Food Security in the Middle and Lower Reaches of Yangtze River

粮食安全是近年来国际社会关注的热点问题,但焦点多集中在耕地面积减少对粮食安全的威胁方面,而忽视了复种指数的变化对粮食安全的影响。长江中下游地区是中国重要的粮食产区,多熟制种植制度是该区提高粮食产量的重要途径。通过构建数学模型定性分析长江中下游地区耕地复种指数的变化对国家粮食产量波动的影响,并在理论上取得了较大的创新和突破。研究表明:1979—2008年长江中下游地区耕地复种指数下降、粮食和农作物播种面积减少、粮食与农作物播种面积比、粮食产量占全国的比重分别下降7.0、7.2个百分点,通过对耕地复种指数变化与国家粮食产量变异系数的计算与分析,发现长江中下游地区耕地复种指数下降对国家粮食安全影响较为明显。研究认为提高农业机械化水平、进行土地制度创新、强化粮食增产的科技支撑体系、建立和完善粮食信息预警系统等是解决问题的有效措施。

Food security is the focus in the international community, but focus on the threat of arable land decrease, ignoring the multiple crop index （MCI） change in recent years. The middle and lower reaches of Yangtze River is an important grain production area in China, multiple cropping is an important ways of improving yield over there. That qualitative analysis MCI change for the national grain yield fluctution influence through constructing mathematical model in the middle and lower reaches of Yangtze River, it made a great innovation and breakthrough in theory. Research showed that, the MCI, food and crop planting area drops, grain yields percentage of China, grain sowing area and crops area ratio drops respectively 7.0 and 7.2 percentage points in the middle and lower reaches of Yangtze River during1979-2008, to influence on the national food security. Puts forward improving the level of agricultural mechanization, innovation land system, strengthening grain production of science and technology support system, building and perfecting the grain information early warning system for measures were to solve the problems.