1987—2016年中国粮食贸易时空格局演变及贸易结构安全性评估

Spatiotemporal pattern of Chinese food trade and structural security assessment, 1987-2016

粮食进出口贸易结构影响国家粮食安全。在开放的全球粮食贸易系统中,贸易格局与贸易安全水平息息相关,因此,准确评判中国粮食贸易结构的安全程度成为亟待解决的重要问题。本文采用净贸易量计算法、香农熵指数法对中国1987-2016年主要粮食(玉米、小麦、稻米、大豆)的进出口贸易时空格局和贸易结构安全性进行了分析。研究发现:①2008年之前,小麦、大豆以进口为主,玉米、稻米以出口为主,2007-2008年世界粮食危机后皆表现为入超特征。②小麦主要进口国(美、加、澳)较为稳定,大豆、玉米、稻米主要进口国变化较大。③粮食进出口结构安全水平存在差异,总体贸易结构安全程度得到提高。④"反向抑制区"国家粮食进出口比例与其香农熵值成反比,"协同增长区"国家粮食进出口比例与其香农熵值成正比,粮食贸易伙伴进出口比例与其对本国贸易结构稳定性的贡献度呈非线性关系。本文揭示了1987-2016年间中国4种粮食对外贸易的时空格局变化,分析了粮食贸易结构演变的动态特征,丰富了对中国粮食贸易的实证研究。

Grain import and export structure affects national grain trade security. In an open global food trading system, trade pattern determines the level of security. Therefore, assessing the security level of China’s food trade structure has become an important issue to be examined. In this study,net trade volume calculation and Shannon entropy index methods were used to analyze China’s grain trade from 1987 to 2016. The study found that:(1) Prior to 2008, wheat and soybeans were mainly imported, and corn and rice were mainly exported. After the world food crisis in 2007-2008, all four grains showed the characteristics of importation.(2) The major wheat source countries(the United States, Canada, and Australia) are relatively stable, and the major source countries of soybean, maize, and rice have changed greatly.(3) There are differences in the security level of grain import and export structure. The overall trade structural security has improved.(4)The proportion of national grain import and export in the"reverse inhibition zone"is inversely proportional to its Shannon entropy. However, that of the"collaborative growth zone"is directly proportional. There is a nonlinear relationship between the proportion of grain imports and exports and its contribution to the stability of domestic trade structure. This study revealed the spatiotemporal changes of China’s foreign trade of four staple grains from 1987 to 2016, analyzed the dynamic characteristics of the change of grain trade structure, and enriched the empirical research on China’s grain trade.