中国粮食产量时空格局演变研究

粮食安全是国家战略安全的重要组成部分，在经济新常态下如何夯实农业基础地位、保障粮食安全成为政府与学界共同关注的命题。运用粮食产量变化系数、变异系数、空间分析方法研究了中国粮食产量时空演变格局与粮食安全问题。结果表明：2000-2003年受城镇化和工业化快速推进占用优质农田和大量青壮年劳动力进城务工的影响，粮食播种面积下降导致产量出现波动下滑；2004-2015年，粮食直补、农业税减免、基本农田保护、耕地红线等系列政策促进粮食产量实现“十二连增”。粮食作物类型时序变化表现为玉米产量大幅增长，由1990年的9 681.9×10⁴ t增长为2015年的22 463.2×10⁴ t，稻谷、小麦产量呈现小幅增长态势。2000-2015年中国粮食生产重心逐渐由西南向东北偏移。从各大区域对粮食总产的贡献率来看，1990-2015年南方沿海区对中国粮食总产的贡献率下降幅度最大，达-5.02%，东北地区对全国粮食总产的贡献率增幅最高，为7.75%。中国粮食产量安全区域范围在逐年增加，由2000年的11个省份增加至2015年的16个省，然而，未来粮食安全应关注粮食结构、粮食品质、食品安全、农田生态环境等方面的研究。

Spatial-temporal evolution of grain production in China

Grain security is a condition related to the ongoing availability of food,which is the important component of the national security. Consolidating the basic position of agriculture and ensuring food security has become a common concern of the government and the academic community under the new economic normality in China. Using the coefficient of grain production variation,the coefficient of variation and the spatial analysis method, the paper studied spatial-temporal evolution of grain production and current situation of grain security in China.We can get the following conclusions: (1)From 2000 to 2003,due to the rapid urbanization and industrialization which led to the sharply occupation of high quality farmland and the migration of a large number of young workforce from countryside to city,the sowing areas decreased,total grain production declined with fluctuation. (2)From 2004 to 2015,the Chinese government had implemented a series of policies,such as food subsidies,agricultural tax relief,the protection of basic farmland and arable land,which promoted the continuous growth of grain production for the twelve consecutive years. (3)As to different grain crops,corn production had increased substantially from 9 681.9×10⁴ t in 1990 to 22 463.2×10⁴ t in 2015,while the production of rice and wheat showed a slight growth trend. In addition,this paper analyzed the regional distribution of grain production. The gravity of grain production showed deviation,shifted from southwest to northeast during 2000-2015. As to the contribution rate of grain production in different regions to the total grain production of China,southern coastal areas showed the biggest decrease rate -5.02%;On the other side,the northeast region had the highest contribution rate increase,which was 7.75%,and the contribution rate in Mongolia and Xinjiang Uygur Autonomous Region increased 2.61%. The concentration of rice production was further improved,mainly concentrated in the middle and lower reaches of the Yangtze River and northeast China,and the wheat production was concentrated in the Huang-Huai-Hai Region and the middle and lower reaches of the Yangtze river,corn production was mainly distributed in northeast China. The area coverage of grain yield security had been increasing,the number of provinces where food yield is sufficient increased from 11 to 16,with more than 400 kg grain production per capita. In the future,grain security is not just concerned with yield security,food structure safety,food safety and ecological environment safety caused by grain production should be paid more and more attention to in all directions and at many levels.