Study On System Of Cultivated Land Forewarning In Developed Area

The cultivated land is the base of mankind's existence and social-economic development, the most essential production means of grain producing and the important material basis of agricultural reproducing. With the reforming and opening to the outside world, the quantity and quality of cultivated land in our country descend quickly, which has a strong impact on grain supply and brings hidden trouble on grain security. Therefore, theoretical and empirical study on setting up the early warning system of cultivated land is very meaningful.This paper introduced the meaning of grain security first, set different targets according to short and long-term characteristic of cultivated land forewarning. Then according to the theory of system, the sustainable development theory, the scarcity theory of land, the early warning theory, adopted the goal early warning coefficient method and statistic pre-warning method to construct the short and long-term mechanism of cultivated land prewarning. we aimed at some sides such as the targets set, the index systerm established, the alarming degree determed, and the measure put forward to research. At last it carried out the empirical study to Jiangsu Province. The thesis included 3 parts:In the Part 1, the paper introduced the relation concepts and methods of cultivated land prewarning, and the basic theory of building systerm of cultivated land prewarning. Firstly, the paper applied the economic early warning theory to the research of the cultivated land prewarning, and defined cultivated land prewarning's concept as "a administrative activity of using a certain scientific method, forcasting the future estate of cultivated land, and putting forward countemeasure". Secondly, the paper applied the SIC theory and the DSC theory to the research of the cultivated land prewarning. the paper considered the system of cultivated land prewarning was not an absolutely balanceable system, but relatively was a dynamic and opening system, which had non-linear and controlable characteristics. In the end, the paper set forth the necessity of building system of cultivated land prewarning.In the part 2, the construction of the early warning system of cultivated land is discussed. Based on the premise that different goals were set, the paper constructed the short and long-term index system of cultivated land prewarning according to sensitive principle, credible principle, systemic principle and stable principle. Statistic pre-warning method was applied in the short-term system of cultivated land prewarning. Firstly, the alert limit was ascertained by systematic method. Then the paper choosed the model,...