The Research Of Demarcating Method Of Prime Farmland Which Is Based On Land Evaluation

The demarcation of prime farmland is a systematic scientific issues. At present the adopted way of demarcating the prime farmland is "the quantitative need" in our country. The way only emphasizes the quantity but not the quality, which cause some inferior farmland, even some garden land, forest land have been demarcated as prime farmland, and some demarcated prime farmland has a potential risk of being been destroyed and been occupied. Make the adjustment of prime farmland and fill designated frequently, and be lack of stability. With the help of GIS technology this paper selects the slope of land, scale, traffic location, the conditions of irrigation,types of land which are adjacent to its suitability and other factors which are from the both way of natural conditions and site conditions that are taken into account. Establishing the way of demarcating of prime farmland that is "the quantitative quality" which is based on the land evaluation. This way can reduce the influence of the human factors, not only make our country meet the needs of the prime farmland, but also make the high yield and good quality characteristics of prime farmland with cultivated land's natural conditions and site conditions, only in this way we can truly achieve the purpose of delimiting prime farmland protection areas.First of all, on the basis of summarizing the related research achievements, analyzing the methods of the existing shortcomings of the prime farmland demarcated,the one thing is only paying attention to quantities not think highly of qualities, there are no quality control, the other thing, The connotation of site conditions are not well considered, this paper clears and definite the research Targets -building the method of delimiting prime farmland.that is, first, qualitative evaluation, then combine the location and the quantities.Second, this study builds index assessed system of the cultivated land selected into prime farmland, which includes three levels seven index, the hydraulic infrastructure index, the slope index, the distance from cultivated land to urban, the distance from cultivated land to rural residential land, the distance from cultivated land to main road index, other land effect adjacent cultivated land index, with the help of GIS technology, seem Dong Gang city as the object of the study, using the method of classification assignment make the index assessed quantized,to get the evaluated results of the cultivated land.Finally, according to the evaluated results of cultivated land, combined with the needs of the prime farmland quantities, use ARCGIS9.2 technology, locating the prime farmland, in this way we can fix the boundary of prime farmland.