基于海外耕地投资的中国粮食供给安全研究

海外耕地投资是中国企业走出去,参与国际投资合作,获取耕地资源的重要手段。海外耕地投资能够通过国际合作和粮食进口,增加中国粮食供给,对国内粮食市场产生重大影响。基于柯布道格拉斯生产函数模型,对粮食播种面积、粮食成灾面积、农业机械总动力、农村用电量、粮食生产劳动力人数、有效灌溉面积、农业产品生产价格指数、农膜施用量、化肥施用折纯量、农药施用量等10个因素进行模型参数筛选,拟合中国粮食总产量关于粮食产量影响因子的函数关系,测算中国国内粮食生产总量;同时通过时间序列数据拟合出口粮、工业用粮、饲粮、种子粮以及粮食损耗的函数模型,测算中国国内粮食需求总量;在此基础上,通过情景分析法模拟不同情景下,中国在海外生产的粮食进入中国市场的比例,并以此作为影响中国粮食总产量的因子之一,构建关于中国粮食总供给的函数模型,分别测算不同情境中海外耕地投资生产的粮食对中国粮食供给安全的影响程度。研究结果表明,悲观情景和一般情境中,海外耕地投资生产的粮食对中国粮食安全的影响并不显著,乐观情境中中国海外耕地投资对中国粮食安全产生显著影响。进一步研究表明,当海外耕地投资粮食进口率超过75.3%时,海外耕地投资会对中国粮食供给安全产生显著影响。研究结论和建议:目前中国海外耕地投资对中国粮食安全的影响并不显著;中国的海外耕地投资能够直接或间接增加中国粮食供给,并且供给量显著提高,存在提高中国粮食供给率,保障国家粮食安全的巨大潜力,决策部门需要重视海外耕地投资,引导海外耕地投资良性发展。

Research of China's food supply security based on farmland investment overseas

Farmland Investment Overseas is an important measure for Chinese companies to go out and participate in the international investment cooperation,to obtain an important means of cultivated land resources,which will increase Chinese food supply level,influence the domestic grain market through the international cooperation and food imports.Based on Cobb-Douglas production function model,we choose factors of the area sown to grain,grain inundated area,total power of agricultural machinery,rural electricity consumption,labor force of grain production,effective irrigation area of applying river,agricultural product producer price index,the amount of films,fertilizer to fit China's domestic grain production function model.Then we work out the demand functions of rations,industrial grain,fodder,seed grain and grain loss.On this basis,through the scenario analysis method to simulate different scenarios,we simulate the ratio of grain exporting into the Chinese market in overseas production,one of the factors that affect China's grain production,to establish Chiua's grain supply function model,measuring the influence of different situations on the grain supply safety level of China.The research results show that under the pessimistic scenario and the general situation,the farmland investment in the production of grain,the farmland investment overseas has no significant influence on China's grain supply safety while under the optimistic situation,it has significant influence.Further research shows that Farmland Investment Overseas will have a significant impact on China's grain supply safety on the condition that the importing rate exceeds 75.3％.Research conclusions and recommendations:the farmland investment overseas has no significant influence on China's grain supply safety currently though its influence is increasing,which shows great potential to Chinese grain supply safety.It's urgently recommended that the departments attach great importance to farmland investment overseas in the future to guide its development.