基于双边界二分式CVM法的耕地生态价值评价——以重庆市为例

Appraisal of the Ecological Value of Cultivated Land Based on Double-Bounded Contingent Valuation Methods

评价耕地生态价值有利于了解耕地生态外部性大小,为政府制订合理的耕地补偿政策提供依据,实现耕地资源的可持续利用。本文以重庆市为例,采用双边界二分式CVM法的Logistic模型,从城镇居民的支付意愿和农民的受偿意愿两个角度评价耕地生态价值。研究结果显示:①按5%的折现率计算,在WTP和WTA法下重庆耕地生态总价值分别为876亿元和2132亿元;②耕地资源具有重大的生态价值;③城镇总体支付意愿和农民总体受偿意愿存在较大差距,目前情况下政府应采取农业补贴等形式解决耕地生态外部性问题。

There are externalities in the use of cultivated land, but there is no rational compensation for positive externality, and no effective restraint and containment for negative externality in China. Under the present system, farmers make use of their cultivated land for economic interests and ignore social and ecological opportunity costs. This pattern will lead to a reduction in cultivated land, quality degradation and environment pollution, and also seriously threaten food safety and sustainable agriculture. The ecological value of cultivated land should be evaluated objectively in order to reveal the extent of cultivated land ecological externalities. Research into the evaluation of the ecological value of cultivated land remains in the primary phase as there are many different methods with various results, most of which focus on urban WTP and ignore rural WTA. If WTA is ignored, it is difficult to build a rational compensation policy and incentive mechanisms for the ecological value of cultivated land. In order to solve this problem, views of urban WTP and rural WTA are taken into consideration. This paper uses Chongqing city as a focal city and applies logistic models of double-bounded contingent valuation methods to evaluate the ecological value of cultivated land. The results indicate that based on a 5% discount rate, the total ecological value of cultivated land in Chongqing is 87.6 billion CNY with WTP views and 213.2 billion CNY with WTA views. There is important ecological value under WTP and WTA method. There is a wide gap between urban WTP and rural WTA and therefore the government need to adopt measures to solve the ecological externalities of cultivated land, such as through agricultural subsidies.