The Study On Chinese Grain Security Cost And Its Stucture Optimization

In a certain period of time, demand for grain in China is in a tendency of sticky increase, so it is fairly important to ensure sustainable grain security. Grain security is the typical public goods, which requires government to input adequate resources into production, distribution and reservation to guarantee the realization of national grain security. Since the foundation of PRC, Chinese government has accomplished outstanding achievement in ensuring grain security and food and nutritional standard of Chinese residents has been greatly improved, all of which not only provide the effective guarantee for economic construction and the social stability and harmony, but also make contribution to the global grain security. On the other hand, China has spent heavily in achieving grain security, including those direct economic expenses in the explicit aspects like production, distribution and reservation and those in implicit aspects like cost of land and water resources for producing grain and the opportunity cost of numerous farmers who are engaged in grain production. The input of the cost asks for efficiency. Only through the scientific cost input mode can we achieve rational utilization of resources and make the sustainable grain security possible. Meanwhile, there should be a rational level for government to pursue grain security. It is unnecessary and uneconomical to pursue grain security beyond the rational range. Therefore, how to use scientific cost input mode under the rational level of grain security to achieve sustainable grain security is of great significance in practice.On the basis of above consideration, the dissertation first of all advances the hypothesis that the government pursues certain level of grain security during a certain period of time, and then it analyzes the optimal cost input mode at the assumed level of grain security by chance constrained programming model, which is to realize the rational utilization of resources and sustainable grain security.The dissertation can be divided into four parts.The first part is the first chapter, which introduces the background, significance and current research progress of the study, advancing the proposition that "grain security is guaranteed and the cost input is optimized".The second part includes chapter two, three and four. This part analyzes the cost spent in those explicit aspects like production, distribution and reservation in China's grain security, figuring out that the cost input has well guaranteed grain security, but there is still room for cost optimization in every aspect. The third part, including chapter five and six, analyzes the cost spent in the implicit aspects like grain producers' opportunity cost and cost of water and land resources utilization. It is believed that grain producers who choose to produce grain bear much higher opportunity cost while making contribution to national grain security. The cost of resources utilization like water and arable land resources in grain security is also very high. Therefore, the author advances the idea that the resources cost in grain security can be saved by virtual transaction of water and land resources.The fourth part includes chapter seven and eight. This part is the design of the optimization of grain security cost and advancement of corresponding suggestion. According to the reality that the cost of grain security keeps too high, the dissertation puts forward following opinions: one is that the input for grain security should be based on certain level, the other is that the internal link between each aspect of grain security should be considered in order to integrate resources and make input according to certain proportion. Only through these two means can we both guarantee grain security and optimize the structure of cost input and realize sustainable grain security. With the assumed level of grain security, the paper estimates the cost input mode corresponding to certain level of grain security by chance constrained programming model. Based on the analysis and evaluation of the result, the paper puts forward suggestion and points out weak points of the study.The study has made innovations in the following aspects.The first innovative point is the research thinking which breaks through the thinking emphasizing the guarantee of grain security while ignoring the cost input in grain security research. The paper considers grain security should be based on sustainability. High cost or low efficiency will both have impact on sustainable grain security. Then it advances the idea of optimal cost input mode on the basis of certain level of grain security. The second one is the research approach. The paper adopts Monte Carlo to estimate grain spatial transferring cost and uses chance constrained programming to analyze the optimal cost input mode of grain security. The third point is the theoretical innovation. The paper proposes suggestion for optimizing grain security cost and realizing sustainable grain security after analyzing the cost of China's grain security and making design of its optimization.