Returns from matching management resolution to ecological variation in a coral reef fishery

When managing heterogeneous socioecological systems, decision-makers must choose a spatial resolution at which to define management policies. Complex spatial policies allow managers to better reflect underlying ecological and economic heterogeneity, but incur higher compliance and enforcement costs. To choose the most appropriate management resolution, we need to characterize the relationship between management resolution and performance. We parameterize a model of the commercial coral trout fishery in the Great Barrier Reef, Australia, which is currently managed by a single, spatially homogeneous management policy. We use this model to estimate how the spatial resolution of management policies affect the amount of revenue generated, and assess whether a more spatially complex policy can be justified. Our results suggest that economic variation is likely to be a more important source of heterogeneity than ecological differences, and that the majority of this variation can be captured by a relatively simple spatial management policy. Moreover, while an increase in policy resolution can improve performance, the location of policy changes also needs to align with ecological and socioeconomic variation. Interestingly, the highly complex process of larval dispersal, which plays a critical ecological role in coral reef ecosystem dynamics, may not demand equally complex management policies.     

生态产品价值实现的政策工具探究

生态产品价值实现,是通过政策工具干预供给者的行为,激励其做出符合私人和公共利益的决策。为探究政府、市场在政策干预中的作用,将政策工具主要分为市场化工具以及非市场化工具,分析政策工具的干预方式,并对适用范围进行界定。为进一步探究政策工具的理论基础及实践成效,围绕其现行制度下的合法性（即符合公共利益且获得更广泛的社会接受）,研究以收益分配及产权义务为纲,引入收益及产权矩阵。依据收益在社会及私人之间的分配及应尽产权义务的范围,政策干预原则主要分为污染者付费、受益者付费、结构调整及能力建设4类。在此基础上,对已有政策工具在矩阵框架下的分布进行合法性分析。研究结果既有助于对政策工具的全面深入理解,也将有利于政策制定者科学决策。通过制定合法性的激励机制,解决市场失灵,最终实现“绿水青山”向“金山银山”的转化。     

The link between international trade and the global distribution of invasive alien species

Invasive alien species (IAS) exact large biodiversity and economic costs and are a significant component of human-induced, global environmental change. Previous studies looking at the variation in alien species across regions have been limited geographically or taxonomically or have not considered economics. We used a global invasive species database to regress IAS per-country on a suite of socioeconomic, ecological, and biogeographical variables. We varied the countries included in the regression tree analyses, in order to explore whether certain outliers were biasing the results, and in most of the cases, merchandise imports was the most important explanatory variable. The greater the degree of international trade, the higher the number of IAS. We also found a positive relationship between species richness and the number of invasives, in accord with other investigations at large spatial scales. Island status (overall), country area, latitude, continental position (New World versus Old World) or other measures of human disturbance (e.g., GDP per capita, population density) were not found to be important determinants of a country’s degree of biological invasion, contrary to previous studies. Our findings also provide support to the idea that more resources for combating IAS should be directed at the introduction stage and that novel trade instruments need to be explored to account for this environmental externality.

生态产品价值实现研究进展

生态产品价值实现是解决环境外部性、保护生态系统功能和完整性的重要机制。基于已有研究和试点案例,对生态产品的狭义及广义概念进行了界定;鉴于资金充足程度对试点项目的重要性,按照资金来源,将生态产品价值实现模式分为公众付费、公益组织付费、政府付费以及多元付费,且对其特点、适用范围、优点及局限进行对比分析,为筹集资金、落实受益者付费原则提供技术支撑;按照问题描述、识别生态产品/受益方(买方)/供给方(卖方)、交易条件、价值交易机制、监测与成效分析框架对试点案例的生态产品价值实现机理及路径进行剖析,提出选择适当的价值实现工具,并强化监测指标的选取及成效分析,以提升资金效率和生态保护效益。     

Uncertainty in Impact and Externality Assessments - Implications for Decision-Making (13 pp)

Goal, Scope and Background Many disciplines, amongst them LCIA, environmental impact and external cost assessments, are often faced with evaluating trade-offs between two or more alternative options in terms of a range of incommensurable indicators. Using process modeling and valuation, these indicators are quantified at mid- or endpoint levels. Recent discussion amongst LCA experts showed that because of the mutually exclusive aspects of uncertainty and relevance, the midpoint/endpoint debate is controversial and difficult to reconcile. This article is aimed at a more quantitative analysis of mid- and endpoint impacts, and the implications of uncertainty for decision-making. Methods The consequences for decision-making of uncertainties of endpoints are analysed quantitatively for the example of ExternE results, by employing statistical hypothesis testing. The Analytic Hierarchy Process (AHP) is then used to demonstrate the use of multi-criteria techniques at midpoint levels. Results and Discussion Statistical hypothesis testing at the endpoint level shows that for the ExternE example, probabilities of mistakenly favouring one alternative over another when they are in reality indistinguishable can be as high as 80%. Therefore, the best estimate of external cost is inadequate for most policy making purposes. Indicators at midpoint levels are more certain, but since they are only \proxy attributes\, they carry a hidden uncertainty in their relevance. Conclusion If endpoint information is too uncertain to allow a decision to be made with reasonable confidence, then the assessment can be carried out in midpoint terms. However, midpoint indicators are generally further removed from people's experience, and less relevant to the question that people actually want to solve. Nevertheless, if this ultimate question is unanswerable (within the certainty required by the decision-maker), a decision can be made on the basis of stakeholders' subjective judgments about the more certain midpoint levels. The crucial point is that these judgments are able to intuitively incorporate many aspects that impact modeling and valuation has trouble quantifying, such as perceived risk, distribution of burdens and benefits, equity, ethical, moral, religious and political beliefs and principles, immediacy and reversibility of potential impacts, voluntariness, controllability and familiarity of exposure, or perceived incompleteness of human knowledge.