Assessing Agricultural Land Resources in China Based on Classification of Function and Value of Agricultural Land
中国各省份农地资源价值量估算——基于对农地功能和价值分类的分析

In addition to the economic value of its production, agricultural land plays an important role in air and water purification, biodiversity maintenance, landscape exhibition, and social security and stability. However, the true value of agricultural land is obscured because of defective market mechanisms, leading to unprotected agricultural land resources. We suggest that functions of agricultural land should include economic production, social security and ecological services. Using 2009 as the appraisal year and using the cobb-douglas function and approximate market law, we dynamically estimated the comprehensive value of agricultural land by examining economic output values, ecological service values and social guarantee values of agricultural land resources for 30 provinces from 1994 to 2009. The results show that the social security and ecological service values are far greater than the economic output of agricultural land. The social security value of agricultural land accounts for a sizeable proportion of the total value of agricultural land, and this is rising. The fundamental cause of rural-urban land conversion is the lower return on land agricultural use, which inevitably leads to other uses that have higher benefits. In the process of conversion, economic benefits improve but social benefit and ecological benefits are lost, leading to a net loss in social welfare. In order to achieve the optimal allocation of resources, the opportunity cost of land conversion, including the economic cost, social cost and environmental cost should be evaluated from the perspective of sustainable development. There is no doubt that the ecological service value and social guarantee value of agricultural land are important portions of the overall value of agricultural land. Our analysis will be helpful to social policy-makers and improve the social and ecological objectives of land use.