沙区沙化土地封禁保护补偿标准的估算——最小数据方法在甘肃省民勤县的运用

论文以甘肃省民勤县沙化土地封禁保护实践工作为研究背景,运用最小数据方法,估算了激励沙区农户将沙化耕地自愿转化为封禁土地的生态补偿（封禁补偿）标准。以水资源服务表征土地管理方式转变之后的生态系统服务产出,由调查获得的农户机会成本推导出了水资源服务供给曲线,并计算出了封禁补偿标准与土地转化比例、水资源服务供给量之间的定量关系。研究结果表明：1）实施封禁补偿,可激励农户改变沙化耕地利用方式,减少农业用水需求量,增加生态用水供给量,对民勤和石羊河流域生态保护意义重大;2）民勤县规划封禁保护区总面积为1.55万hm²,期望水资源服务产出为1.02亿m³,需要按照19 770元·hm^-2的标准补偿才能激励农户实现这一政策目标;3）以新一轮退耕还林补偿标准3 600元·hm^-2为参照线,只能促使3.51%的沙化耕地转化为封禁土地,在设计封禁补偿机制时,需要提高封禁补偿标准。

Estimation of Compensation Standard for Enclosed Protection Area of Desertified Land in Sandy Area—Application of Minimal Data Method in Minqin County of Gansu Province

The desertification of land leads to a decrease in the amount of usable land and brings about serious economic and social problems, making it one of the most catastrophic environmental problems confronting human society today. In order to curb desertification effectively, in 2013, the State Forestry Bureau started to implement the subsidy system for the protection and closure of desertified lands in areas where land desertification was serious. During the construction of desertification protection reserves, the ecological compensations is vital, which encourages farmers to voluntarily exchange their semi-desertified or desertified farmlands with lands that produce low yields and need huge irrigation requirements. Based on the practice of enclosed protection area of desertified land in Minqin County of Gansu Province, the paper estimated the ecological compensation standard that can encourage the farmers to voluntarily transform desertified farmland into protected zone with Minimal Data Method. The paper used water resource service to represent the ecosystem services output after the change of land management and deduced the water resources service supply curve based on the opportunity cost of the farmers obtained from survey. The quantitative relationships between the compensation standard, land conversion ratio and water resource supply were calculated. The results show that: 1) The implementation of the compensation can encourage farmers to change the way cultivating land use, reduce irrigation water and increase ecological water supply in Minqin County and Shiyang River Basin. 2) According to the plan of Minqin County, the total area of the forbidden reserve will be 15 500 hm² and the expected water resources output will be 102 million m³, which could be achieved by a compensation standard of 19 770 yuan/hm². 3) Based on a compensation standard (3 600 yuan/hm²) for new-round Grain for Green Project, only 3.51% of the desertified land could be transformed into protected zone. Therefore, the compensation standard should be improved.