Representing mediating effects and species reintroductions in Ecopath with Ecosim

Ecosystem models play an important role in supporting ecosystem approaches to management. To improve the representation of how ecosystems work, ecosystem models should be able to represent mediating effects (e.g., habitat provision) that species provide to each other as well as species (re)introductions, both common situations that can strongly influence ecosystem dynamics. We examine how such processes can be incorporated into Ecopath with Ecosim (EwE), a widely used tool for represent aquatic ecosystems with the potential to support ecosystem-based management. We used the reintroduction of sea otters (Enhydralutris) to the west coast of Vancouver Island, British Columbia, Canada as a case study. The model demonstrates how to account for benefits provided by kelp forests by contributing to primary production, increased feeding areas and food availability through prey retention. It also demonstrates how the reintroduction and range expansion of sea otters can be represented in Ecospace, and the implications of these options.     

依据(代)生物体对化学品的反应预测对生态系统服务功能的影响

保护生态系统服务功能越来越多地被作为风险评估的目标,但是目前生态风险评估的终点和评估生态系统服务功能受到的潜在影响之间有很大的差距。作者提出了一个框架,将常用的生态毒理学终点与对种群和群落的影响以及生态系统的服务功能联系起来。这个框架建立在机制效应模型的长足进步上,这些模型旨在跨越多种生物组织,并解释各种生物相互作用和反馈。为了说明这一点,作者引入了2个研究案例,它们采用了已完善和已验证的机制效应模型：鱼种群的inSTREAM个体模型和AQUATOX生态系统模型。他们还展示了动态能量平衡理论可以为解释组织级毒性提供一种通用货币。他们认为,一个基于机制模型的框架,可以预测化学品暴露对生态系统服务的影响,再结合经济估值,可以为环境管理提供一种有用的方法。作者强调了使用这个框架的潜在好处以及未来工作中需要解决的挑战。
精选自Forbes, V. E., Salice, C. J., Birnir, B., Bruins, R. J.F., Calow, P., Ducrot, V., Galic, N., Garber, K., Harvey, B. C., Jager, H., Kanarek, A., Pastorok, R., Railsback, S. F., Rebarber, R. and Thorbek, P. (2017), A framework for predicting impacts on ecosystem services from (sub)organismal responses to chemicals. Environmental Toxicology and Chemistry, 36: 845–859. doi: 10.1002/etc.3720
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3720/full
     

Habitat loss, trophic collapse, and the decline of ecosystem services

The provisioning of sustaining goods and services that we obtain from natural ecosystems is a strong economic justification for the conservation of biological diversity. Understanding the relationship between these goods and services and changes in the size, arrangement, and quality of natural habitats is a fundamental challenge of natural resource management. In this paper, we describe a new approach to assessing the implications of habitat loss for loss of ecosystem services by examining how the provision of different ecosystem services is dominated by species from different trophic levels. We then develop a mathematical model that illustrates how declines in habitat quality and quantity lead to sequential losses of trophic diversity. The model suggests that declines in the provisioning of services will initially be slow but will then accelerate as species from higher trophic levels are lost at faster rates. Comparison of these patterns with empirical examples of ecosystem collapse (and assembly) suggest similar patterns occur in natural systems impacted by anthropogenic change. In general, ecosystem goods and services provided by species in the upper trophic levels will be lost before those provided by species lower in the food chain. The decrease in terrestrial food chain length predicted by the model parallels that observed in the oceans following overexploitation. The large area requirements of higher trophic levels make them as susceptible to extinction as they are in marine systems where they are systematically exploited. Whereas the traditional species-area curve suggests that 50% of species are driven extinct by an order-of-magnitude decline in habitat abundance, this magnitude of loss may represent the loss of an entire trophic level and all the ecosystem services performed by the species on this trophic level.     

Challenges to interdisciplinary research in ecosystem-based management

Despite its necessity, integration of natural and social sciences to inform conservation efforts has been difficult. We examined the views of 63 scientists and practitioners involved in marine management in Mexico's Gulf of California, the central California coast, and the western Pacific on the challenges associated with integrating social science into research efforts that support ecosystem-based management (EBM) in marine systems. We used a semistructured interview format. Questions focused on how EBM was developed for these sites and how contextual factors affected its development and outcomes. Many of the traditional challenges linked with interdisciplinary research were present in the EBM projects we studied. However, a number of contextual elements affected how mandates to include social science were interpreted and implemented as well as how easily challenges could be addressed. For example, a common challenge is that conservation organizations are often dominated by natural scientists, but for some projects it was easier to address this imbalance than for others. We also found that the management and institutional histories that came before EBM in specific cases were important features of local context. Because challenges differed among cases, we believe resolving challenges to interdisciplinary research should be context specific.     

An Ecosystem Management Program and Assessment Process for Ontario National Parks

Abstract: An ecosystem management program and assessment process was developed to standardize an ecosystem-based approach to protecting the ecological integrity of Ontario's national parks. The elements of the ecosystem management program collectively represent the dominant planning and technical aspects of ecosystem management. Within the program, 11 specific products—ecosystem conservation plan, greater park ecosystem inventory and analysis, greater park ecosystem scope, area of cooperation, stakeholder analysis, partnership group management guidelines, scientific research program, ecological indicators, ecological integrity monitoring program, information network, and communication strategy—are considered requisite tools to improve the scientific understanding required for park management within the context of greater park ecosystems and to increase communication and coordination among governments and citizens to improve decision making. The formal process uses evaluation criteria associated with the 11 products to assess progress in developing an ecosystem management program and the content of the related products. The assessment process, which provides comprehensive identification of a park's specific ecosystem management needs, has been applied to all national parks in Ontario in the past year, which has had the immediate effect of refining their ecosystem management programs.     

Capacity of Management Plans for Aquatic Invasive Species to Integrate Climate Change

Abstract:  The consequences of climate change will affect aquatic ecosystems, including aquatic invasive species (AIS) that are already affecting these ecosystems. Effects on AIS include range shifts and more frequent overwintering of species. These effects may create new challenges for AIS management. We examined available U.S. state AIS management plans to assess each program's capacity to adapt to climate-change effects. We scored the adaptive capacity of AIS management plans on the basis of whether they addressed potential impacts resulting from climate change; demonstrated a capacity to adapt to changing conditions; provided for monitoring strategies; provided for plan revisions; and described funding for implementation. Most plans did not mention climate change specifically, but some did acknowledge climatic boundaries of species and ecosystem sensitivities to changing conditions. Just under half the plans mentioned changing environmental conditions as a factor, most frequently as part of research activities. Activities associated with monitoring showed the highest capacity to include information on changing conditions, and future revisions to management plans are likely to be the easiest avenue through which to address climate-change effects on AIS management activities. Our results show that programs have the capacity to incorporate information about climate-change effects and that the adaptive-management framework may be an appropriate approach.     

Climate change,marine policy and the valuation of Mediterranean intertidal ecosystems

This commentary describes a gap in the qualitative and quantitative knowledge of the provision of benefits to humans from the intertidal ecosystems of the Mediterranean and offers a framework for quantification of the benefits provided by these systems. The identification of such benefits, understanding their spatial distribution and their subsequent quantification will be critical to the design of policy responses to future climate change, sea level rise and seawater acidification. A baseline understanding of the current state of ecosystem functions, as well as of the provision of related ecosystem services, is therefore needed. Further, researchers must strive to generate forecasts of the changes in these functions and services conditional on policy responses and the range of expectations for climate change.     

Breaking through the Crisis in Marine Conservation and Management: Insights from the Philosophies of Ed Ricketts

Abstract:  Over the last decade, 2 major U.S. commissions on ocean policy and a wide range of independent sources have argued that ocean ecosystems are in a period of crisis and that current policies are inadequate to prevent further ecological damage. These sources have advocated ecosystem-based management as an approach to address conservation issues in the oceans, but managers remain uncertain as to how to implement ecosystem-based approaches in the real world. We argue that the philosophies of Edward F. Ricketts, a mid-20th-century marine ecologist, offer a framework and clear guidance for taking an ecosystem approach to marine conservation. Ricketts' philosophies, which were grounded in basic observations of natural history, espoused building a holistic picture of the natural world, including the influence of humans, through repeated observation. This approach, when applied to conservation, grounds management in what is observable in nature, encourages early action in the face of uncertainty, and supports an adaptive approach to management as new information becomes available. Ricketts' philosophy of "breaking through," which focuses on getting beyond crisis and conflict through honest debate of different parties' needs (rather than forcing compromise of differing positions), emphasizes the social dimension of natural resource management. New observational technologies, long-term ecological data sets, and especially advances in the social sciences made available since Ricketts' time greatly enhance the utility of Ricketts' philosophy of marine conservation.     

Using a fisheries ecosystem model with a water quality model to explore trophic and habitat impacts on a fisheries stock: A case study of the blue crab population in the Chesapeake Bay

Recent calls for the development of ecosystem-based fisheries management compel the development of resource management tools and linkages between existing fisheries management tools and other resource tools to enable assessment and management of multiple impacts on fisheries resources. In this paper, we describe the use of the Chesapeake Bay Fisheries Ecosystem Model (CBFEM), developed using the Ecopath with Ecosim (EwE) software, and the Chesapeake Bay Water Quality Model (WQM) to demonstrate how linkages between available modeling tools can be used to inform ecosystem-based natural resource management. The CBFEM was developed to provide strategic ecosystem information in support of fisheries management. The WQM was developed to assess impacts on water quality. The CBFEM was indirectly coupled with the WQM to assess the effects of water quality and submerged aquatic vegetation (SAV) on blue crabs. The output from two WQM scenarios (1985-1994), a baseline scenario representing actual nutrient inputs and another with reduced inputs based on a tributary management strategy, was incorporated into the CBFEM. The results suggested that blue crab biomass could be enhanced under management strategies (reduced nutrient input) when the effective search rate of blue crab young-of-the-year's (YOY's) predators or the vulnerability of blue crab YOY to its predators was adjusted by SAV. Such model linkages are important for incorporating physical and biological components of ecosystems in order to explore ecosystem-based fisheries management options.     

The Need to Disentangle Key Concepts from Ecosystem‐Approach Jargon

The ecosystem approach—as endorsed by the Convention on Biological Diversity (CDB) in 2000—is a strategy for holistic, sustainable, and equitable natural resource management, to be implemented via the 12 Malawi Principles. These principles describe the need to manage nature in terms of dynamic ecosystems, while fully engaging with local peoples. It is an ambitious concept. Today, the term is common throughout the research and policy literature on environmental management. However, multiple meanings have been attached to the term, resulting in confusion. We reviewed references to the ecosystem approach from 1957 to 2012 and identified 3 primary uses: as an alternative to ecosystem management or ecosystem‐based management; in reference to an integrated and equitable approach to resource management as per the CBD; and as a term signifying a focus on understanding and valuing ecosystem services. Although uses of this term and its variants may overlap in meaning, typically, they do not entirely reflect the ethos of the ecosystem approach as defined by the CBD. For example, there is presently an increasing emphasis on ecosystem services, but focusing on these alone does not promote decentralization of management or use of all forms of knowledge, both of which are integral to the CBD's concept. We highlight that the Malawi Principles are at risk of being forgotten. To better understand these principles, more effort to implement them is required. Such efforts should be evaluated, ideally with comparative approaches, before allowing the CBD's concept of holistic and socially engaged management to be abandoned or superseded. It is possible that attempts to implement all 12 principles together will face many challenges, but they may also offer a unique way to promote holistic and equitable governance of natural resources. Therefore, we believe that the CBD's concept of the ecosystem approach demands more attention. La Necesidad de Desenredar Conceptos Clave del Argot Ambiente‐Estrategia     

Valuing Ecosystem Services in Terms of Ecological Risks and Returns

Abstract: The economic valuation of ecosystem services is a key policy tool in stemming losses of biological diversity. It is proposed that the loss of ecosystem function and the biological resources within ecosystems is due in part to the failure of markets to recognize the benefits humans derive from ecosystems. Placing monetary values on ecosystem services is often suggested as a necessary step in correcting such market failures. We consider the effects of valuing different types of ecosystem services within an economic framework. We argue that provisioning and regulating ecosystem services are generally produced and consumed in ways that make them amenable to economic valuation. The values associated with cultural ecosystem services lie outside the domain of economic valuation, but their worth may be expressed through noneconomic, deliberative forms of valuation. We argue that supporting ecosystem services are not of direct value and that the losses of such services can be expressed in terms of the effects of their loss on the risk to the provision of the directly valued ecosystem services they support. We propose a heuristic framework that considers the relations between ecological risks and returns in the provision of ecosystem services. The proposed ecosystem‐service valuation framework, which allows the expression of the value of all types of ecosystem services, calls for a shift from static, purely monetary valuation toward the consideration of trade‐offs between the current flow of benefits from ecosystems and the ability of those ecosystems to provide future flows.     

Using ecosystem-services assessments to determine trade-offs in ecosystem-based management of marine mammals

The goal of ecosystem-based management (EBM) is to support a sustainable and holistic multisectored management approach, and is recognized in a number of international policy frameworks. However, it remains unknown how these goals should be linked to assessments and management plans for marine fauna, such as mammals and fish stocks. It appears particularly challenging to carry out trade-off analyses of various ocean uses without a framework that integrates knowledge of environmental, social, and economic benefits derived from nonstationary marine fauna. We argue this gap can be filled by applying a version of the ecosystem-service approach at the population level of marine fauna. To advance this idea, we used marine mammals as a case study to demonstrate what indicators could operationalize relevant assessments and deliver an evidence base for the presence of ecosystem services and disservices derived from marine mammals. We found indicators covering common ecosystem service categories feasible to apply; examples of indicator data are already available in the literature for several populations. We encourage further exploration of this approach for application to marina fauna and biodiversity management, with the caveat that conceptual tensions related to the use of the ecosystem service concept itself needs to be addressed to ensure acceptance by relevant stakeholders.     

Obscuring Ecosystem Function with Application of the Ecosystem Services Concept

Abstract: Conservationists commonly have framed ecological concerns in economic terms to garner political support for conservation and to increase public interest in preserving global biodiversity. Beginning in the early 1980s, conservation biologists adapted neoliberal economics to reframe ecosystem functions and related biodiversity as ecosystem services to humanity. Despite the economic success of programs such as the Catskill/Delaware watershed management plan in the United States and the creation of global carbon exchanges, today's marketplace often fails to adequately protect biodiversity. We used a Marxist critique to explain one reason for this failure and to suggest a possible, if partial, response. Reframing ecosystem functions as economic services does not address the political problem of commodification. Just as it obscures the labor of human workers, commodification obscures the importance of the biota (ecosystem workers) and related abiotic factors that contribute to ecosystem functions. This erasure of work done by ecosystems impedes public understanding of biodiversity. Odum and Odum's radical suggestion to use the language of ecosystems (i.e., emergy or energy memory) to describe economies, rather than using the language of economics (i.e., services) to describe ecosystems, reverses this erasure of the ecosystem worker. Considering the current dominance of economic forces, however, implementing such solutions would require social changes similar in magnitude to those that occurred during the 1960s. Niklas Luhmann argues that such substantive, yet rapid, social change requires synergy among multiple societal function systems (i.e., economy, education, law, politics, religion, science), rather than reliance on a single social sphere, such as the economy. Explicitly presenting ecosystem services as discreet and incomplete aspects of ecosystem functions not only allows potential economic and environmental benefits associated with ecosystem services, but also enables the social and political changes required to ensure valuation of ecosystem functions and related biodiversity in ways beyond their measurement on an economic scale.     

The Role of Prices in Conserving Critical Natural Capital

Abstract: Until recent decades, economic decision makers have largely ignored the nonmarket benefits provided by nature, resulting in unprecedented threats to ecological life‐support functions. The economic challenge today is to decide how much ecosystem structure can be converted to economic production and how much must be conserved to provide essential ecosystem services. Many economists and a growing number of life scientists hope to address this challenge by estimating the marginal value of environmental benefits and then using this information to make economic decisions. I assessed this approach first by examining the role and effectiveness of the price mechanism in a well‐functioning market economy, second by identifying the issues that prevent markets from pricing many ecological benefits, and third by focusing on problems inherent to valuing services generated by complex and poorly understood ecosystems subject to irreversible change. I then focus on critical natural capital (CNC), which generates benefits that are essential to human welfare and have few if any substitutes. When imminent ecological thresholds threaten CNC, conservation is essential and marginal valuation becomes inappropriate. Once conservation needs have been met, remaining ecosystem structure is potentially available for economic production. Demand for this available supply will determine prices. In other words, conservation needs should be price determining, not price determined. Conservation science must help identify CNC and the quantity and quality of ecosystem structure required to ensure its sustained provision.     

Effects of land use,cover, and protection on stream and riparian ecosystem services and biodiversity

Protected areas are an important part of broader landscapes that are often used to preserve biodiversity or natural features. Some argue that protected areas may also help ensure provision of ecosystem services. However, the effect of protection on ecosystem services and whether protection affects the provision of ecosystem services is known only for a few services in a few types of landscapes. We sought to fill this gap by investigating the effect of watershed protection status and land use and land cover on biodiversity and the provision of ecosystem services. We compared the ecosystem services provided in and around streams in 4 watershed types: International Union for Conservation of Nature category II protected forests, unprotected forests, unprotected forests with recent timber harvesting, and unprotected areas with agriculture. We surveyed 28 streams distributed across these watershed types in Quebec, Canada, to quantify provisioning of clean water, carbon storage, recreation, wild foods, habitat quality, and terrestrial and aquatic biodiversity richness and abundance. The quantity and quality of ecosystem services and biodiversity were generally higher in sites with intact forest—whether protected or not—relative to those embedded in production landscapes with forestry or agriculture. Clean-water provision, carbon storage, habitat quality, and tree diversity were significantly higher in and around streams surrounded by forest. Recreation, wild foods, and aquatic biodiversity did not vary among watershed types. Although some services can be provided by both protected and unprotected areas, protection status may help secure the continued supply of services sensitive to changes in land use or land cover. Our findings provide needed information about the ecosystem service and biodiversity trade-offs and synergies that result from developing a watershed or from protecting it.     

Effects of human demand on conservation planning for biodiversity and ecosystem services

Safeguarding ecosystem services and biodiversity is critical to achieving sustainable development. To date, ecosystem services quantification has focused on the biophysical supply of services with less emphasis on human beneficiaries (i.e., demand). Only when both occur do ecosystems benefit people, but demand may shift ecosystem service priorities toward human-dominated landscapes that support less biodiversity. We quantified how accounting for demand affects the efficiency of conservation in capturing both human benefits and biodiversity by comparing conservation priorities identified with and without accounting for demand. We mapped supply and benefit for 3 ecosystem services (flood mitigation, crop pollination, and nature-based recreation) by adapting existing ecosystem service models to include and exclude factors representing human demand. We then identified conservation priorities for each with the conservation planning program Marxan. Particularly for flood mitigation and crop pollination, supply served as a poor proxy for benefit because demand changed the spatial distribution of ecosystem service provision. Including demand when jointly targeting biodiversity and ecosystem service increased the efficiency of conservation efforts targeting ecosystem services without reducing biodiversity outcomes. Our results highlight the importance of incorporating demand when quantifying ecosystem services for conservation planning.     

One Hundred Questions of Importance to the Conservation of Global Biological Diversity

Abstract:  We identified 100 scientific questions that, if answered, would have the greatest impact on conservation practice and policy. Representatives from 21 international organizations, regional sections and working groups of the Society for Conservation Biology, and 12 academics, from all continents except Antarctica, compiled 2291 questions of relevance to conservation of biological diversity worldwide. The questions were gathered from 761 individuals through workshops, email requests, and discussions. Voting by email to short-list questions, followed by a 2-day workshop, was used to derive the final list of 100 questions. Most of the final questions were derived through a process of modification and combination as the workshop progressed. The questions are divided into 12 sections: ecosystem functions and services, climate change, technological change, protected areas, ecosystem management and restoration, terrestrial ecosystems, marine ecosystems, freshwater ecosystems, species management, organizational systems and processes, societal context and change, and impacts of conservation interventions. We anticipate that these questions will help identify new directions for researchers and assist funders in directing funds.     

What are we protecting? Fisher behavior and the unintended consequences of spatial closures as a fishery management tool

Spatial closures like marine protected areas (MPAs) are prominent tools for ecosystem-based management in fisheries. However, the adaptive behavior of fishermen, the apex predator in the ecosystem, to MPAs may upset the balance of fishing impacts across species. While ecosystem-based management (EBM) emphasizes the protection of all species in the environment, the weakest stock often dominates management attention. We use data before and after the implementation of large spatial closures in a North Pacific trawl fishery to show how closures designed for red king crab protection spurred dramatic increases in Pacific halibut bycatch due to both direct displacement effects and indirect effects from adaptations in fishermen's targeting behavior. We identify aspects of the ecological and economic context of the fishery that contributed to these surprising behaviors, noting that many multispecies fisheries are likely to share these features. Our results highlight the need either to anticipate the behavioral adaptations of fishermen across multiple species in reserve design, a form of implementation error, or to design management systems that are robust to these adaptations. Failure to do so may yield patterns of fishing effort and mortality that undermine the broader objectives of multispecies management and potentially alter ecosystems in profound ways.     

Payments for Ecosystem Services as a Framework for Community-Based Conservation in Northern Tanzania

Abstract:  Payments for ecosystem services (PES) are an increasingly promoted approach to conservation. These approaches seek to develop financial mechanisms that create economic incentives for the maintenance of ecosystems and associated biodiversity by rewarding those who are responsible for provision of ecological services. There are, however, few cases in which such schemes have been used as a strategy for conserving wildlife in developing countries and very few operational examples of such schemes of any sort in sub-Saharan Africa. In savannah ecosystems, large mammal populations generally depend on seasonal use of extensive areas and are widely declining as a result of habitat loss, overexploitation, and policies that limit local benefits from wildlife. Community-based conservation strategies seek to create local incentives for conserving wildlife, but often have limited impact as a result of persistent institutional barriers that limit local rights and economic benefits. In northern Tanzania, a consortium of tourism operators is attempting to address these challenges through an agreement with a village that possesses part of a key wildlife dispersal area outside Tarangire National Park. The operators pay the community to enforce voluntary restrictions on agricultural cultivation and permanent settlement in a defined area of land. The initiative represents a potentially cost-effective framework for community-based conservation in an ecologically important area and is helping to reconcile historically conflicting local and national interests relative to land tenure, pastoralist livelihoods, and conservation. Wider adaptation of payments for ecosystem services approaches to settings where sustaining wildlife populations depends on local stewardship may help address current challenges facing conservation outside state-protected areas in savannah ecosystems in sub-Saharan Africa and other parts of the world.