Planting Area Conversion Between Grain And Cash Crops In Zhejiang Under Cultivated Land Constraints

The nature problem of grain is the cultivated land and cultivated land is the essence of the land which is the most necessary production factors for human beings to access to grain. Our country has a prominent contradiction between human beings and land use. With excessive people and less land, we are short of arable land resources and the cultivated land to per capita is far lower than the world average. The unreasonable use of cultivated land problems will be increasingly prominent by the further growth of population, accelerating of country’s industrialization and urbanization along with interests driving. Zhejiang province is characterized by complex topography, low hills, a shortage of arable land and low rate of self-sufficiency for grain. Many of their grain rely on imports or cover the shortage from other province, only part of food can be self-supporting, so that it creates constant pressure to the country’s grain production. Zhejiang province has made50%supply target, but as one of the national big province in economy, the phenomenon of farmland and crop land conversion is serious, moreover, the planting area as well as grain planting proportion in reducing year by year. Based on this, this paper will take Zhejiang province’s food and vegetable production for example. By building the system dynamic model and inputting the historical data, the model simulates the planting area changes and production of vegetables and grain after ten years. Ultimately, long-term change trend of grain production and the cultivated land structure use can be found. By using of subsidies and tax, the model can proceed intervention simulation under different proportion and we can observe the changes of crops planting area different intervention conditions, finding the right intervention ways and strength. Finally, combined with the actual situation of Zhejiang, a feasible suggestions to plan land structure use has been raised. The feasible Suggestions will provide references to optimize the cultivated land use and guarantee the supply of grain and safeguard national food security.