耕地保护的外部性及其测算——以河南省焦作市为例

Externality and Its Calculation of Cultivated Land Protection: A Case Study of Jiaozuo City

本文基于耕地生态系统服务功能的类型、作用过程及其形态等特征的不同,重构了耕地利用效益体系,并从外部性供体、受体出发对耕地保护外部性的概念、类型、影响及其补偿进行了界定和分析,同时提出了耕地保护外部性测算的思路和方法。以河南省焦作市为研究区域,以2006年为研究时段,运用综合方法和条件价值法对其耕地保护的外部性进行了测算。研究结果表明:①耕地利用效益体系中的生态和社会效益具有强烈的外部性,该外部性促进耕地非农化速度进一步加快;②耕地保护总体外部性包括区内外部性和区际外部性,耕地保护总体外部性补偿依赖于区内外部性和区际外部性实现程度;③基于综合方法测算出的焦作市2006年耕地保护外部性为15542.3元/hm2,基于CVM测算出的焦作市2006年耕地保护外部性为1020.4元/hm2,该测算结果可作为耕地保护外部性补偿的最高和最低标准;④耕地保护区际外部性测算表明,孟州市、沁阳市、武陟县、温县和修武县是耕地保护外部性盈余县(市),属于区际补偿输入区,市辖区和博爱县是耕地保护外部性赤字县(区),属于区际补偿输出区;⑤应在耕地保护外部性测算基础上,尽快建立耕地保护外部性内部化机制。

This paper first reconstructs the utilization benefits systems for cultivated land on the basis of the types, affecting process, form and features of cultivated land ecosystem. The concepts, categories, influence and compensation methods of the externalities of cultivated land protection are also defined and analyzed in view of the theory of donator and acceptor of externalities. Meanwhile, the thinking and approaches to the calculation of externalities are proposed. Then, the externalities of cultivated land protection in 2006 in Jiaozuo city are calculated by contingent valuation method （CVM） and synthetic approach. The results are as follows. Firstly, the cultivated land utilization benefits system is composed of economic benefit, social benefit and ecological benefit. The ecological and social benefit of cultivated land utilization are more for public goods than with the features of consumption, so the ecological benefit and social benefit of cultivated land utilization are external benefits, which is the crucial reason for cultivated land conversion. Secondly, the overall externalities of cultivated land are composed of regional externality and interregional externality. The achievements of the overall externalities are influenced by the achievements of regional and interregional externalities. The synthetic approach and contingent valuation method （CVM） can effectively measure the value of externality. The externality based on CVM show a positive willingness to pay （WTP） in a hypothetical market. The value is small, and can be used as the minimum value of externality compensation criterion. The externalities based on synthetic approach are big because neither the regional economic and social conditions nor the residents＇ ability to pay are considered. Therefore, it can be used as the maximum value of externalities compensation criterion. Thirdly, the overall externality of cultivated land in 2006 in Jiaozuo is 15542.3 RMB per hectare in synthetic approach, and 1020.4 RMB per hectare in CVM. The maximal value and minimum value of externality compensation of different amount of cultivated land can also be measured according to the grain production capacity of different cultivated lands. Fourthly, the interregional externality values of Mengzhou, Qinyang, Wuzhi, Wenxian and Xiuwu are positive while the interregional externality values of Urban and Boai are negative. Therefore, Mengzhou, Qinyang, Wuzhi, Wenxian and Xiuwu can be defined as compensation surplus area, while Urban and Boai are compensation deficit area. Lastly, the economic compensation mechanism and cultivated land protection system, including regional compensation and interregional compensation, are constructed to protect cultivated land in China.