非点源污染最佳管理措施成本-效益分析研究综述

Current Situation and Research Progress of Cost-effectiveness Analysis Methods for Nonpoint Source Pollution Control

农业非点源污染由于其特有的分散性及时空异质性等特点,对其进行有效的控制较为困难。最佳管理措施(BMPs,Best Management Practices)是实现流域农业非点源污染控制的有效手段。国内外相关经验表明,合理的BMPs配置能够有效控制农业非点源污染的影响。而对BMPs方案的成本-效益进行评估则是实现BMPs优化配置的前提条件。通过对目前国外及中国的成本—效益研究案例剖析基础上,分析了BMPs成本—效益研究的现状、意义以及局限性。结果表明:(1)目前BMPs配置的成本—效益研究多以"典型"区域或小尺度模型为基础进行分析,未考虑不同研究区之间的差异;(2)仅关注某种措施的生态效益,或者BMPs实施中所发生的直接成本(如:成本—收益、成本效益曲线),未考虑BMPs实施的外部成本;(3)对BMPs成本-效益评估的不确定性表征不足。基于上述评述,对中国今后流域非点源污染控制BMPs配置研究中成本—效益分析及相关政策的制定和实施提供了一些建议和启示。

To manage nonpoint source pollution at the agricultural watershed is an ongoing challenge that needs to take into account of the cost-effectiveness between environmental and economic objectives. However, a great number of related studies indicated that the considerable expenditures on reducing noncompliance attributable to agricultural nonpoint source pollution were not economical and that incentive schemes to enhance compliance have been inadequately targeted. This implies a need for cost-effective targeting of measures to control non-point source pollution from agriculture. Cost- Effectiveness Analysis （CEA） of best management practices for agricultural non-point source pollution has been given paramount importance in achieving the targeted water quality in worldwide. CEA is an applied appraisal technique that provides a ranking of alternative measures on the basis of their costs and effectiveness for achieving the environmental objectives. Through summarizing the status, significance and methodological limitations related CEA studies in China, Europe and U.S, it was found that most CEA-related studies were based on models of representative farms without capturing the variability among real-world farms. Attentions were paid on a single ecological effect of measures or on cost estimates of the sectors directly involved in the pollutant-reduction program, whereas co-benefits, trade-offs and external costs were not examined. Uncertainties in both cost and effectiveness estimates did not incorporate. Policy implications and recommendationsfor future research in China were also proposed.