环境选择模型在生态系统管理中的应用——以黑河流域额济纳旗为例

Choice Modeling and Its Potential Application to Ecosystem Management and Preservation:Taking Ejina Banner as an Example

以黑河流域额济纳旗生态系统的可持续发展管理为例,选取了水费、绿洲面积、水质、本地动物种类和数目作为额济纳旗生态系统管理的5种属性,根据额济纳旗生态恢复和保护目标及社会经济发展目标确定了属性状态值,采用部分正交因子法设计了调查问卷,于2002年7月至8月间,在黑河流域随机抽样调查了1000户居民,以分析环境属性的价值和不同替代情景的补偿剩余价值。分析结果表明了主要环境属性的部分价值:面积为0.22元/km2,动物类型为6.09元/种,动物数量为-7.11元/104头,水质从较差到一般状态为20.04元/户、水质从较差到较好为27.67元/户、水质从较差到好为38.87元/户。分析结果表明,对额济纳旗生态系统的管理而言,提高水质和增加动物的种类是合适的选择。最后,结合实证研究展望了选择模型研究应该解决的问题。

Comparison to contingent valuation method, choice models can provide a wealth of information on the willingness of respondents to make trade-offs between the individual attributes and their likely responses to different product circumstances. The need for an assessment of the non-market benefits of preservation of Ejina Banner's ecosystem is clear. In this paper, we take it as a case to analyze the value of individual environmental attribute and aggregate changes of preservation ecosystem service. Obtaining accurate benefit estimates using CM requires detailed descriptions of the alternative use of resource. In our experiment, the results of focus group sessions indicated that the framing goals and the issue of interest can be described with five key attributes: water rates, oasis area, water quality, animal type and animal number. The attribute levels have been selected by the preservation and developing goal. The fractional factor and the blocking of the orthogonal experimental design were used to combine various attribute levels and presented to respondents as choice sets.As a line with contingent valuation method, we used a 12-page paper with maps depicting the reason why Ejina Banner's ecosystem needed preservation, by which means the ecosystem services could be restored from their current level and some choice problems. We designed the questionnaire along with the survey booklet distributing to 1000 households in the Heihe drainage basin from July to August, 2002. At the same time, a multi nominal logit model was employed to estimate the welfare of protecting Ejina Banner's ecosystem. Results from 1000 replies indicate that the estimation of willingness to pay for a change in one of the choice attributes, and aggregate value of various scenarios have been calculated according to the estimated indirect utility function. Finally, we put forward some suggestions on how to apply the choice models in developing countries, and believe future efforts can be made to apply CM efficiently accompanied with benefit-cost analysis.