Abstract:
As the essence of cultivated land, prime farmland under the special protection is significant for the cultivated land output and the national food security. Thus the delineation and layout of the prime farmland is not only the starting point for the prime farmland protection, but also the foundation of the efficient use and effective supervision for the prime farmland. It has found that the layout of prime farmland is affected by various factors, such as natural factors, economic and social factors, ecological environmental factors, etc. Although some studies have considered to put individual geological environmental indicators into cultivated land and prime farmland layout, there is still a lack of systematic investigation about the geological environmental factors in prime farmland layout study. From the constraints of the geological environment on cultivated land use, in this paper, we took Xuzhou urban planning area as an example, to build the evaluation index system of regional geological environment suitability for cultivated land, which was constructed from five aspects: topographic conditions, soil conditions, hydrological conditions, geological disasters and geological environment problems, and used the matter-element model to evaluate the geological environmental suitability of cultivated land. Furthermore, after superimposing the evaluation results with the prime farmland layout scheme of the General Land Use Planning in Xuzhou City (2006-2020), there were arable land with less suitable grade or unsuitable grade which should be transferred out of the Prime Farmland Protected Area. At the same time, because of the constraint of the prime farmland retention index, the same amount of cultivated land with suitable grade or general suitable grade should be transferred from the general agricultural land area into the Prime Farmland Protected Area. Finally, the optimization scheme of the prime farmland layout based on the geological environment constraint was obtained. The result showed that according to the relationship between cultivated land use and geological environment, it was the premise for optimizing the layout of prime farmland to integrate the factors including topography, soil, hydrology, geological disaster and geological environmental problems to establish indicator system of the region geological environmental suitability assessment. There were 2 431.69 hm2 of the prime farmland whose suitability level was less suitable grade and unsuitable. Through transferring the less suitable and unsuitable prime farmland, then adding the suitable and less suitable cultivated land from the general farmland area, the new layout of prime farmland in study area was optimized from the point of geological environment. In this paper, we explored the optimization path of prime farmland layout in region based on the constraints of geological environment, which can also be used in the layout optimization of urban and rural construction land, industrial and mining land and other types of land, in order to promote the "mine and land integration" in process of spatial planning decision and management.