关键词: 粮食供需, 粮食运输, 数学模型, 市场原理, 经济水平差距

Abstract:

To evaluate the vulnerability of cereals transportation and cereals stock estimated from the current land use and demandsupply on cereals in China, two types of numerical models (nonmarket type and market type) were developed.The result revealed risks in decreasing cereals stock in hinterlands of productive regions and in urban regions far from productive regions, especially coastal zones in south China.In a nonmarkettype model, cereals were transported from a gridcell with positive cereals stock to a gridcell with negative cereals stock.Cereals shortage has gradually disappeared, when increasing transportation intensity coefficient in this model.Thus, excessive cereals in productive regions have also decreased and regional unbalance of cereal stocks has almost disappeared. In a markettype model, each gridcell absorbed cereals from surroundings in proportion to its GDP.Some coastal urban regions showed a quick accumulation of cereals stocks, with the increasing of the cereals absorption coefficient.It appears that widescale cereals crisis has appeared in inland regions.

Key words: cereals balance, cereals transportation, numerical model, market system, economic potential