Biodiversity metrics and biodiversity values for the public appraisal of biodiversity: synthesising and extending the evidence.

世界正面临着生物多样性危机。尽管生物多样性具有价值，但在经济决策中却被系统地忽视了。该提案将通过综合迄今为止在评估生物多样性方面的经验教训，并确定如何将这些价值观纳入决策的主流，从而积极影响生物多样性政策和结果，来解决这一缺陷。正如众多出版物所强调的那样，生物多样性通过多种生态系统服务（如授粉、气候调节、防洪）为人类福祉做出贡献。几十年的研究使我们能够准确地估计土地利用决策与生物多样性结果和生态系统服务价值之间的关系。然而，人们也从仅仅知道生物多样性的存在（“存在价值”）中获得幸福。本研究将探讨将这些价值纳入经济决策的两种方法：1)通过测量人们对生物多样性的支付意愿（WTP）；2)通过实现商定的生物多样性政策目标（如净收益）的成本：基于成本的方法。该提案将首先严格审查和综合WTP方法。如果存在一致的WTP估计，这是经济学家首选的方法——因为它通过权衡收益与成本，允许在生物多样性结果和其他商品（例如卫生、教育）之间进行资源的最佳配置。然而，在WTP估计中存在众所周知的不一致（例如，WTP对生物多样性供应的增加没有反应，并且对框架敏感），这是因为人们难以解释生物多样性与金钱的权衡。因此，我们将审查如何实施另一种估值程序-基于成本的方法。在英国，25年环境计划的目标是“自然积极”或生物多样性净收益。这可以用作基于成本的方法的目标。虽然目标明确，但净收益目标并没有说明应该使用哪种生物多样性指标来衡量是否实现了净收益。这是有问题的，因为生物多样性是多方面的，人们的福祉受到不同方面的不同影响。以反映公众偏好（公众对生物多样性的需求）的生物多样性指标为导向，以成本为基础的方法需要确定生物多样性的不同方面如何影响福祉，以及这些方面如何与生物多样性的不同指标相吻合。为了实现这一目标，我们将综合不同的生物多样性指标。我们将结合一个专门设计的经济实验来整理生物多样性指标与人们偏好之间的关系，并以具有代表性的样本进行该实验，以提供人们重视生物多样性的哪些方面的经验证据，同时避免要求他们执行困难和有争议的生物多样性-金钱权衡。一旦建立了适当的指标来评估实现净收益，提案将通过新能源汽车模型套件确定达到目标的成本。这种隐含的生物多样性的货币价值将用于政策评估，并指导决策远离有害的生物多样性影响。最后，本研究将使用新能源汽车模型来证明不同政策方法对土地利用、福利和生物多样性的影响。鉴于HMT关于生物多样性经济学的Dasgupta评论的建议，该研究议程非常及时。它将对其他指标驱动的方法产生明显的影响（例如，金融部门的披露和住房开发的净收益要求）。此外，该研究将作为如何估计生物多样性价值并将其应用于政策评估的原则证明，鉴于该研究希望影响的英国政府公共投资评估指南的声誉，该研究将在全球范围内使用。

The world is facing a biodiversity crisis. Despite biodiversity's value, it is systematically ignored in economic decision making. This proposal will address this shortcoming by synthesising the lessons to date in valuing biodiversity, and establishing how these values can be mainstreamed in decision-making to positively affect biodiversity policy and outcomes. As numerous publications highlight, biodiversity contributes to people's wellbeing through multiple ecosystem services (e.g. pollination, climate regulation, flood prevention). Decades of research allows us to accurately estimate the relationship between land-use decisions and both biodiversity outcomes and ecosystem service values. Yet, people also derive well-being from simply knowing that biodiversity is there ("existence value"). This study will explore the two methods for incorporating these values within economic decision making: 1) via measuring people's Willingness-To-Pay (WTP) for biodiversity; 2) via the cost of meeting an agreed policy target (e.g. net-gain) for biodiversity: a cost-based approach.The proposal will first critically review and synthesise the WTP approach. If consistent estimates of WTP exist, it is the economist's preferred approach - as it allows for the optimal allocation of resources across biodiversity outcomes and other goods (e.g. health, education) by weighing benefits against costs. However, there are well known inconsistencies in WTP estimates (e.g. WTP is unresponsive to increases in biodiversity provision, and is sensitive to framing), which arise because people struggle to interpret biodiversity-money trade-offs. We will therefore review how an alternative valuation procedure - the cost-based approach - could be operationalised.In the UK the target in the 25-year Environment Plan is "nature-positive" or biodiversity net-gain. This can be used as the target for a cost-based approach. While the aim is clearly articulated, the net-gain ambition does not state which metric of biodiversity should be used to measure whether net-gain is achieved. This is problematic given biodiversity is multifaceted, and people's well-being is differently affected by different aspects. Orienting the cost-based approach around a biodiversity metric that reflects public preferences (what the public want in relation to biodiversity) requires establishing how well-being is affected by different aspects of biodiversity and how these tally with different metrics of biodiversity.To achieve this aim, we shall synthesise the different metrics of biodiversity. We will couple this with an economic experiment specifically designed to tease apart the relationships between biodiversity metrics and people's preferences, and conduct this experiment with a representative sample to provide empirical evidence of which aspects of biodiversity people value, while avoiding asking them to perform difficult and controversial biodiversity-money trade-offs. Once an appropriate metric is established to assess achieving net-gain, the proposal will determine the cost meeting the target though the NEV modelling suite. This implied monetary value of biodiversity would then be used in policy appraisal and guide decisions away from harmful biodiversity impacts. Finally, the research will use the NEV modelling to demonstrate the land-use, welfare and biodiversity, implications of different policy approaches. The research agenda is extremely timely given the recommendations of HMT's Dasgupta Review on the Economics of Biodiversity. It will have obvious ramifications for other metric-driven approaches (e.g. disclosure in the financial sector and the net-gain requirement for housing developments). Moreover, the research will act as a proof-of-principle for how biodiversity's value can be estimated and applied in policy appraisal, which will be of use globally given the reputation of the UK government guidelines on public investment appraisal that this research hopes to influence.