| The gradation and classification and appraisement of arable land is a fundamental and public and strategic subject-matter which meets the needs of social economy development and scientific land management. It is a milestone of basic construction in management of land and resource in China. But it can't be perfect in a short period because of its complexity. The vegetable plot quality was selected as the research object from many contents which were in great need of studying, and the calculation method and law was probed which reflected the influence of markets on the quality of vegetable plot in order to provide the reference to the classification and appraisement of vegetable plot.To begin with, the status of the evaluation of vegetable plot quality in the gradation and classification and appraisement of arable land and the status of markets in the evaluation of the comprehensive quality of vegetable plot were discussed in the thesis. Then, the relations between the study of market-vegetable plot quality and the evaluation of land and arable land were elaborated. Next, the author dissected the system of market factors which affected the comprehensive quality of vegetable plot and put forward the principle of selecting the dominant factors. Through discussion, the rank and position of markets was considered as the leading factors during the evaluation of market-vegetable plot quality. Based on it, the subordinate index collection of leading factors were listed. In addition, the system of expression and calculation on the influence degree of markets on the comprehensive quality of vegetable plot was founded. And the new conceptions such as product sale exchange coefficient were posed and quantitated in the system. And the way of concentric circles survey to obtain the basic data was introduced in the thesis. And how to rank the market applying Delphi approach and how to ascertain the market factors' weight and marks were presented in the following parts. The author showed theprocess and methods of establishing the influence range model and influence degree decay model. Finally, the means of how to take the form of map to describe the models depending on GIS software was given in this paper.To explore and verify the operation and correction of the system, the author selected the typical Luancheng County in the plain region as a demonstration. According to the concrete situation of Luancheng County, the author judged the market system growth perfect. And the markets in Luancheng were classified into 4 grades. The Chengguan Market was ranked as first class. And the markets of second class consisted of 6 markets such as Yehe Market and Xiying Market. The third class markets had nine, for example Nanqiema Market and Nangao Market and etc. The markets of the fourth class included 13 markets. Based on it, the chain functions between market area and annual total turnover, annual total turnover and annual agricultural byproducts turnover, annual agricultural byproducts turnover and the influence distance of markets were put forward. The equations were listed respectively: y =0.0606X+19.5 (R2 =0.7904); y =0.4311X-14.62 (R2 =0.993); y =2.1105Ln(X)-2.6268 (R2 =0.6594). At the same time, the functions could be used to acquire the farthest survey border in the course of the detailed survey. At last, the model of market influence on vegetable plot quality with the change of distance was set up. The model of first class market was y = -0.2612x3 + 5.518x2 - 38.473x + 129.05 (R2= 0.812). The model of first class market disclosed the phenomenon of three obvious influence phases. At the range of 0-5 Km around the first class market, the influence of market on the vegetable plot quality changed faster, and the range belonged to a zone of high investment-output in vegetable planting. And within the limits of 5-9 Km, the influence changed steady. The limits belonged to a transitional zone of investment-output in vegetable planting. Within the scope of 9-14 Km, the influence of markets on vegetable plot quality changed faste... |
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