Comprehensive Evaluation Of Arable Land Quality And Its Application Based On LESA System

Arable land resource is a material foundation of human survival and development, the changes of the quantity and quality can not be ignored in the history of human development, with the development of science and technology and the food issues appearance, the attention of study of arable land protection from the quantity to the quality and quantity of both. Quality of arable land affected not only by the natural environment, but to a large extent is closely related to human activities, the quality of arable land research starts relatively late in China, that focuses on the evaluation of the soil quality or soil quality changes under certain conditions, the site of arable land conditions are always neglected. It makes the evaluation results can not keep a great consistency to the actual production situation of arable land. The study learn the LESA(Land Evaluation and Site Assessment) ideological from the United States, use mathematics to establish a comprehensive evaluation model concludes land quality and site conditions to ensure the integrity and accuracy of the evaluation,and make the Danjiangkou city as the study object to conduct the empirical analysis,and have a detail analysis to the application of the evaluation results,The main process is as follows:by literature analysis,using mathematics methods to build LESA evaluation model,detailing the evaluation unit division、evaluation index system and the process of establishing evaluation model. Through the land use survey, soil survey, field research, etc,obtaining the situation of the factors that affect the quality of arable land, Use the Arcgis and other technical to analysis the factors that selected, construct the evaluation system,identified six nature quality factors and four site factors to confirm the comprehensive evaluation model, and for the purpose of improving arable land productivity, finally determine the comprehensive evaluation model of Danjiangkou city:LESA = 0.7 ? LE + 0.3 ? SA.Using the comprehensive evaluation model of Danjiangkou city to calculate the score and then partition the level, ultimately determine the quality of arable land consolidation of Danjiangkou City. Studies suggest the overall quality arable land in Danjiangkou city preferred to 3280.96 hectares, only 10.12 percent of the total cultivated area of the city, and the poor quality preferred to 12,097.53 hectares, accounting for 37.71 percent of the total cultivated area, on the whole, this city has general natural quality but weaker site conditions, the main reason is contiguous of arable land itself is poor, less in estment in the area of irrigation and water conservancy facilities and poor road traffic conditions.Finally, according to the comprehensive quality evaluation study results, analysis the applications in arable land use planning of the evaluation system LESA, that focuses on the application of demarcate the direction of arable land use. And based on the comprehensive evaluation of the results of the quality of Danjiangkou City of arable land, divided into arable land use planning direction threshold point value, depending on the score, the Danjiangkou arable land will be divided into four use directions, it can provide a theoretical basis and technical support for scientific demarcation of arable land use.