中国粮食安全系统脆弱性评价及其驱动机制分析

从粮食安全系统的视角出发,运用VSD的脆弱性分析框架,从暴露性、敏感性、适应能力三个层面构建了中国粮食安全脆弱性评价指标体系,采用主成分分析方法对1991-2015年中国粮食安全脆弱性的暴露性、敏感性、适应能力进行定量分析,并探究了中国粮食安全脆弱性变化的总体趋势及其驱动因子。研究结果表明：（1）暴露性指数呈现出2阶段下降特征,年均下降0.121;敏感性指数呈现出快速上升和基本稳定的两阶段变化特征;适应能力指数则一直上升,年均提高0.117。（2）1991-2015年粮食安全系统脆弱性指数整体呈现下降趋势,表明中国粮食安水平有了明显提高;其变化过程可划分为1991-1999年、2000-2003年和2004-2015年三个阶段,第一、二阶段粮食安全水平的总体提高是基于“吃饱”水平上的提高,而第三阶段是基于“吃好”水平上的提高。（3）人均GDP、城镇化水平和城乡居民人均可支配收入四个因子共同驱动中国粮食安全脆弱性的变化,2000-2015年的第二阶段四因子对粮食安全脆弱性的驱动作用明显小于1991-1999的第一阶段,且第一驱动因子由第一阶段的农村居民人均可支配收入转变为第二阶段的人均GDP和城镇居民可支配收入。

The vulnerability assessment and driving mechanism analysis of China's food security system

China has attained lots of achievements in maintaining its food security in the past two decades. However, the food security system of China is still faced with great challenges and has its typical vulnerability characteristics. From the perspective of food security system, using the VSD (vulnerability acoping siagram) analysis framework, the evaluation index system of food security vulnerability in China was constructed in three dimensions of exposure, sensitivity and adaptive capacity. Based on the statistical data in China from 1991 to 2015, we used the method of principal component analysis to examine the changing characteristics of exposure index, sensitivity index and adaptive capacity index, and revealed the overall trend of food security system vulnerability and its driving factors. The results showed that: (1) The development of exposure index can be divided into rapid decrease stage (1991-2000) and slow decrease stage (2001-2015), and its annual average decline value is 0.121; the development of sensitivity index can be divided into rapid increase stage (1991-2003) and relatively steady stage (2004-2015), while the adaptive capacity index shows a continuous increasing trend during the period of 1991 to 2015, and its annual average increase value is 0.117. (2) The index of food security system vulnerability in China is overall on the decrease, which means that the state of food security in China has been greatly improved. And the changing process of the food security system vulnerability can be divided into three stages of 1991-1999, 2000-2003 and 2003-2015, the first and second stages happened in the age of lower food security level of merely eradicating hunger, and the second decrease stage was in the age of higher food security level of eating more diversified food. (3) The four factors which induced to the change of food security vulnerability in China are per capita GDP, urbanization rate, annual per capita disposable income of urban households (ACDIUH), and annual per capita disposable income of rural households (ACDIRH). In the second stage (2000-2015), the driving effect of the four factors was much smaller than that of the first stage (1991-1999), and the leading driving factor in the first stage was ACDIRH, while in the second stage, the leading driving factors were per capita GDP and ACDIUH. At last, some suggestions are proposed to lower China's food security vulnerability, such as to promote economic growth, increase urban and rural residents' income to eradicate poverty and propel new urbanization.