外部性视角下的节水灌溉技术补偿标准核算——基于选择实验法

合理的补偿标准是节水灌溉技术补偿政策的核心,也是促进农户技术采用的关键内容。论文以石羊河下游民勤县为例,通过选择实验调研和RPL（Random Parameters Logit）模型估计,量化了节水灌溉技术采用的外部效益,并结合特定技术与农户谈判能力讨论了兼顾公平与效率的补偿标准。结果表明：民勤县城乡居民均希望实施节水灌溉技术来改善生态环境,技术采用的外部效益约为1 052.25元/hm²;以膜下滴灌技术为例,合理的补偿标准应在789.15元/hm²左右。从现行政策看,过低的补贴标准难以保障农户切身利益,导致政策响应不足。据此建议,完善成本收益核算体系,将技术采用的外部效益纳入补偿标准的核算中,提升补偿政策的公平性,同时也要根据技术类型及其采用面积进行精准化补偿,保障资金有效利用。

Assessing the Compensation Standard of Water-saving Irrigation Technology from the Perspective of External Benefits: Based on Choice Experiment

Reasonable compensation standard for water-saving irrigation technology can obtain a more positive response and improve policy effectiveness. In theory, the external benefits generated by water-saving irrigation technology are the basis of the compensation policy design. Taking Minqin County as an example, this paper quantified the external benefits of water-saving irrigation technology adopted by the choice experiment and random parameters Logit model, then calculated the compensation standard according to bargaining ability of the stakeholders. The results show that: 1) Both urban and rural residents of Minqin County all hope to improve the regional ecological environment by implementing water-saving irrigation technology. The annual willingness to pay of urban residents is 1 006.99 yuan if all arable land adopts high-efficiency water-saving irrigation technology in the next 10 years and the indicators restore to the best level designed in this article, and that of rural residents is 661.36 yuan. It indicates that the external benefit of technology adoption is obvious, thus the annual total external benefits is 50.96×10⁶ yuan, around 1 052.25 yuan/hm². 2) Accorrding to the natural environment of Minqin County and the adaptability of different technologies, if adopting drip irrigation technology, the reasonable standard should be around 789.15 yuan/hm². Compared with the compensation standard of 150 yuan/hm² in Gansu Province, the current water-saving irrigation technology compensation is too low to maintain farmers’ interests and lead to inadequate policy response. It is suggested that, a complete cost-benefit accounting system should be built which incorporates the external benefits to enhance the fairness of compensation policy. And a precision compensation should be implemented according to technology types and the area to increase financial fund utilization efficiency. Although this study provides a feasible way to quantify the external benefit of water-saving irrigation technology, Minqin County is one of the main sources of dust storms in China, benefits brought by its improved ecological environment for the residents outside the region (e.g., sandstorms reduction, etc.) is not included in the accounting of external benefits. Therefore, in the following study of cost-benefit analysis of water-saving irrigation technology, it is necessary to further explore the benefits of the residents outside the implementing region, so that quantitative results of external benefits can be more comprehensive.