Research For The Balance Of Food Supply And Demand Based On The Quality Of Cultivated Land In China

Grain security is a worldwide problem, which is related to the strategic plan of the country. The state insists on the principle of grain security as the basic grain self-sufficiency. With the increase of population and the improvement of grain consumption, the grain security situation in China becomes more severe. The quantity and quality protection of cultivated land resources is the important prerequisite for ensuring grain security. Understand the inherent law of cultivated land quality and the balance of grain supply and demand provides a feasible way to solve the bottleneck of grain production, which is conducive to improve the utilization efficiency of cultivated land.The study is based on the data of population, grain and arable land in China, regard prefecture level city(District) as the basic research unit. Mainly uses statistical analysis method, and combined with the comparative analysis, qualitative and quantitative analysis, spatial overlay based on GIS and regression simulation method to study the status quo of grain supply and demand balance all over the county. In the perspective of cultivated land quality protection, we constructs quantitative relationship mode between cultivated land quality and grain supply and demand with the national unity than the quality, in order to study the effect. In the meanwhile, the potential of cultivated land is calculated, to divide middle and lower areas of the potential zones and analyze the law of supply and demand balance. Finally, the route of guaranteeing the grain security in our country is put forward.The central study results show firstly that the overall state of grain supply and demand structure of our country is that grain production slightly more than the surplus. The difference between grain supply and demand is obvious, presenting the space feature of western and southern grain shortage, eastern and northern grain adequate. But from the point of view of analysis of prefecture level cities’ number, there are only 48% cities can depend on the food production in the region to meet the grain needs. The high surplus area plays a very important role in protecting grain security and controlling risk of grain supply. Secondly, grain production presents slightly more than the surplus in excellent, high, medium and low quality cultivated land area. The low grain surplus area, low grain deficit area and medium grain surplus area are main types in terms of land supply and demand. High grain deficit area and medium grain deficit area are edge types. Thirdly, the distribution characteristics of cultivated land in our country are that the grain surplus area corresponding to low quality of cultivated land, the grain deficit area corresponding to high quality of cultivated land. Medium quality cultivated land is basically the main type in six grain supply and demand zones. Fourthly, there is a clear correlation between the quality of cultivated land and the balance types of grain supply and demand in China. On the whole, the supply and demand balance of the grain decreases with the increase of the quality of the cultivated land firstly and then decreases. Finally, the medium and low quality cultivated land have obvious regional distribution difference. The main grain supply and demand balance types and land use restriction factors have some regularity in different potential areas.