Research On The Method Of The Grade-determination Of The Cultivated Land

With the practice and research on the grade-determination of the cultivated land , the paper, based on the concept and purpose of the grade-determination of the cultivated land , has analysed the problems existing in the course of practice and summarized the reasons about " the rules of the grade-determination of farming land " which the Ministry of Land and Natural Resources had issued , including the issues about dependence between grading index of cultivated land and utilizing index ,or dependence between grading index of cultivated land and natural index , lack of the nationwide comparativity of the achievement on grade-determination of the cultivated land ,the sudden change indexes between the paddy field and its adjoint nonirrigated farmland, the representativeness of appointed crop and so on.In order to make the current grade-determination method of the cultivated land more rational, the paper has analyzed the natural and social economic factor of cultivated land quality deeply. Many ideas, including the theoretical foundation on grade-determination, the authenticity of the basic materials, the division of the index district, the determination of the appointed crops and their parameters , the largest theory output of the crop and the definition of the suitable range about index district, the control of the equivalence district in the county , the revision of the multiple crop index and the application of GIS ,etc. have been deeply discussed, and the current grading model of the cultivated land has been revised.The paper especially put forward to the view that we can utilize the social comprehensive level of economy of the area to reflect the average use level of the agriculture's potential indirectly. Through the social economic statistics, we adopted mathematics statistical method, such as Principal Component Analysis, systematic cluster's analysis, etc., to calculate potentiality coefficient of theagricultural production in the area, and utilized potentiality coefficient to revise the cultivated land utilizing index of the regional district. With the present influence of ubiquitous agriculture's comparative interests dispelled, it makes the current system of grade-determination of the cultivated land more perfect.Finally, with the support of GIS, the paper took the grade-determination of the cultivated land in Fuqing as an example to illustrate the real feasibility and rationality of the research approach.