青藏高原草地存在价值研究——以玛曲为例

草地存在价值研究是强化人们环境保护意识的有力工具,也是制定资源利用战略的决策依据。运用条件价值评估方法中(Contingent Valuation Method,CVM)的最大意愿支付(Willingness to Pay,WTP)技术,对青藏高原东缘玛曲草地的存在价值进行了系统研究,结果显示:2005年,牧户的平均WTP为339元/a,总存在价值为0.03×10~8元/a;收入与WTP呈显著正相关关系。据此推断,2016年牧户的平均WTP为407元/a,总存在价值为0.033×10~8元/a。存在价值小,主要是因为当地人口基数小。如果考虑玛曲草地对全球生物多样性保育的贡献,以及对黄河水源所具有的涵养功能,则其总存在价值将倍增,其中2005年为636×10~8元/a,2016年为763×10~8元/a,增幅约为20%,与当地居民的收入增长相当。这一结果表明,与玛曲草地的保护成本相比,其存在价值极其显著,应纳入成本-效益分析之中;存在价值具有动态性,应根据收入变化状况进行连续评估,以反映其真实价值,从而确保政策制定者做出正确决策。

The existence value of Qinghai-Tibetan Plateau: a case study on Maqu grassland

Existence value as a non-use value means that people feel lost when something disappeared. Exploring the existence value of grassland is a powerful tool for strengthening our awareness of environmental protection and for developing strategies for resource use. Contingent valuation method (CVM), a survey-based method, can reveal consumer preferences for public goods and services and infer respondents'' willingness to pay (WTP) to improve environmental quality. After several decades of development, it has emerged as the principal means for measuring the existence value. Although it is questioned by its validity and reliability in decision-making processes, it has become a dominant technique for the valuation of non-market environmental costs and benefits since the 1990s. WTP technique of CVM was used to explore systematically the existence value of Maqu grassland, which is located on the eastern of Qinghai-Tibetan Plateau. The results showed that the average WTP of each household was 339 Yuan/a, and the total WTP was 0.03×10⁸ Yuan/a in 2005. WTP was positively related to the income. From 2005 to 2016, the income of local resident increased by about 20%, with the average WTP being 407 Yuan/a in 2016 and the total WTP being 0.033×10⁸ Yuan/a. Compared with other studies, the existence value of Maqu grassland was smaller due to the limited population base. However, if we considered the role of Maqu grassland in maintaining the global biodiversity and its importance for water conservation of the Yellow River, this existence value would increase largely, which reached up to 636×10⁸ Yuan/a in 2005 and to 763×10⁸ Yuan/a in 2016. From 2005 to 2016, the existence value of Maqu grassland increased about 20% which is equalled to an increase of the income. These results suggest that the existence value of Maqu grassland is significant, and we should consider it in cost-benefit analysis. Furthermore, the existence value changes with time and is needed to evaluate continuously in order to make the right decisions.