Study On Decision-making Models Of Demarcating Prime Farmland

Agriculture is the foundation of the national economy, then arable land is the foundation of agriculture. However, the prime farmland is the essence of cultivated land resource. So the protection of prime farmland is the most important task of the protection of cultivated land, which is very important to ensure national food security, maintain social stability, and promote economy to develop comprehensively, coordinately and sustainably. But in recent years, the protection of prime farmland in China is not optimistic, because the amount of prime farmland reduces seriously and the quality of prime farmland degenerates year by year. Besides, the layout is not reasonable. The study to seek scientific and rational ways to delimit prime farmland has great significance to solve these problems.Scholars have done lots of research on how to delimit prime farmland, which mainly focused on quality, quantity and connectivity of prime farmland. However, there is only few consideration on spatial position of prime farmland. With this background, by taking spatial connectivity of prime farmland as a pointcut and associating some relevant theory of decision-making model, this study builds a decision-making model to delimit prime farmland. And this model is verified by taking the Donghai of Lianyungang city as an illustration.According to the description of the problem of the prime farmland demarcation, this thesis divides decision-making model of the prime farmland demarcation into two parts:comprehensive ranking model of arable land and model for selecting arable land as prime farmland. The comprehensive ranking model of arable land determines the priority to be the prime farmland of arable land with some certain rules. This study uses the analytical hierarchical process to determine weight, then ranks by using TOPSIS method. Basing on the determination of the priority of arable land, the model for selecting arable land as prime farmland determines whether arable land is selected as prime farmland when consider of external constraints, this study uses0-1integer programming model to solve this problem.Based on the principle of the selection of evaluation indexes to determine arable land to be prime farmland, and considered of field conditions of Donghai, this thesis constructs evaluation indexes system by taking factors, such as the gently degree of arable land, soil fertility, irrigation conditions, distance to traffic trunk road, radiation of city and town, radiation of peasant residential area and spatial connectivity of arable land into account. Using spatial analytical functions of GIS to attain specific value of each index, then normalize these values, determine weight of each index with analytical hierarchical process, establish a standardized decision matrix, finally, sort arable land through TOPSIS method. According to binding conditions of prime farmland, we determine the final arable land to be selected as prime farmland.This thesis determines the prime farmland of Donghai according to decision-making model. Compared with more weighted indexes of evaluation indexes system, we can find prime farmland defined by decision-making model has guarantees in both quality and quantity, which means that decision-making model is reasonable and practical to implement, and can provide a preferable support to prime farmland delimitation.