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Many marine invertebrate species facing potential extinction have uncertain taxonomies and poorly known demographic and ecological traits. Uncertainties are compounded when potential extinction drivers are climate and ocean changes whose effects on even widespread and abundant species are only partially understood. The U.S. Endangered Species Act mandates conservation management decisions founded on the extinction risk to species based on the best available science at the time of consideration—requiring prompt action rather than awaiting better information. We developed an expert‐opinion threat‐based approach that entails a structured voting system to assess extinction risk from climate and ocean changes and other threats to 82 coral species for which population status and threat response information was limited. Such methods are urgently needed because constrained budgets and manpower will continue to hinder the availability of desired data for many potentially vulnerable marine species. Significant species‐specific information gaps and uncertainties precluded quantitative assessments of habitat loss or population declines and necessitated increased reliance on demographic characteristics and threat vulnerabilities at genus or family levels. Adapting some methods (e.g., a structured voting system) used during other assessments and developing some new approaches (e.g., integrated assessment of threats and demographic characteristics), we rated the importance of threats contributing to coral extinction risk and assessed those threats against population status and trend information to evaluate each species’ extinction risk over the 21st century. This qualitative assessment resulted in a ranking with an uncertainty range for each species according to their estimated likelihood of extinction. We offer guidance on approaches for future biological extinction risk assessments, especially in cases of data‐limited species likely to be affected by global‐scale threats. Incorporación del Cambio Climático y Oceánico en Estudios de Riesgo de Extinción para 82 Especies de Coral  相似文献   

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对全球气候变化原因及发展趋势之浅见   总被引:1,自引:0,他引:1  
分析了引起全球气候变化的各种可能原因,对温室气体、植被破坏、水汽变化等对全球气候变化的影响作了概括总结,阐述了全球气候变化发展趋势及气候变化预测中应注意的问题。  相似文献   

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本文介绍了美国稳定全球气候政策方案选择研究项目的概况,分析了快速变化的世界和慢速变化的世界远景。  相似文献   

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Abstract:  Recent episodes of coral bleaching have led to wide-scale loss of reef corals and raised concerns over the effectiveness of existing conservation and management efforts. The 1998 bleaching event was most severe in the western Indian Ocean, where coral declined by up to 90% in some locations. Using fisheries-independent data, we assessed the long-term impacts of this event on fishery target species in the Seychelles, the overall size structure of the fish assemblage, and the effectiveness of two marine protected areas (MPAs) in protecting fish communities. The biomass of fished species above the size retained in fish traps changed little between 1994 and 2005, indicating no current effect on fishery yields. Biomass remained higher in MPAs, indicating they were effective in protecting fish stocks. Nevertheless, the size structure of the fish communities, as described with size-spectra analysis, changed in both fished areas and MPAs, with a decline in smaller fish (<30 cm) and an increase in larger fish (>45 cm). We believe this represents a time-lag response to a reduction in reef structural complexity brought about because fishes are being lost through natural mortality and fishing, and are not being replaced by juveniles. This effect is expected to be greater in terms of fisheries productivity and, because congruent patterns are observed for herbivores, suggests that MPAs do not offer coral reefs long-term resilience to bleaching events. Corallivores and planktivores declined strikingly in abundance, particularly in MPAs, and this decline was associated with a similar pattern of decline in their preferred corals. We suggest that climate-mediated disturbances, such as coral bleaching, be at the fore of conservation planning for coral reefs.  相似文献   

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Abstract:  Climate change and invasive species are often treated as important, but independent, issues. Nevertheless, they have strong connections: changes in climate and societal responses to climate change may exacerbate the impacts of invasive species, whereas invasive species may affect the magnitude, rate, and impact of climate change. We argue that the design and implementation of climate-change policy in the United States should specifically consider the implications for invasive species; conversely, invasive-species policy should address consequences for climate change. The development of such policies should be based on (1) characterization of interactions between invasive species and climate change, (2) identification of areas where climate-change policies could negatively affect invasive-species management, and (3) identification of areas where policies could benefit from synergies between climate change and invasive-species management.  相似文献   

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Abstract: Economic growth‐the increase in production and consumption of goods and services‐must be considered within its biophysical context. Economic growth is fueled by biophysical inputs and its outputs degrade ecological processes, such as the global climate system. Economic growth is currently the principal cause of increased climate change, and climate change is a primary mechanism of biodiversity loss. Therefore, economic growth is a prime catalyst of biodiversity loss. Because people desire economic growth for dissimilar reasons‐some for the increased accumulation of wealth, others for basic needs‐how we limit economic growth becomes an ethical problem. Principles of distributive justice can help construct an international climate‐change regime based on principles of equity. An equity‐based framework that caps economic growth in the most polluting economies will lessen human impact on biodiversity. When coupled with a cap‐and‐trade mechanism, the framework can also provide a powerful tool for redistribution of wealth. Such an equity‐based framework promises to be more inclusive and therefore more effective because it accounts for the disparate developmental conditions of the global north and south.  相似文献   

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土壤微生物呼吸热适应性被认为是决定陆地生态系统对全球变暖反馈作用的潜在重要机制,可能显著改变未来的气候变化趋势,然而,土壤微生物群落结构变化如何引起土壤微生物呼吸热适应性的研究目前尚存争议.该文针对气候变化对土壤微生物呼吸的影响研究,梳理了当前对土壤微生物呼吸的热适应性是否存在的争议和不同观点与结论,综述了气候变化对土...  相似文献   

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全球气候变化背景下台湾海峡浮游植物的长期变化   总被引:5,自引:0,他引:5  
为了解气候–海洋环境变异的生态影响,阐述并比较了1984~1985年和2006~2008年台湾海峡浮游植物分布的时空变化特征.结果表明:浮游植物物种多样性指数和均匀度分别由3.29和0.62降至2.90和0.55;平均细胞密度增加3.7倍,由372.0×104 cells/m3增加到173 8.8×104 cells/m3;种类组成里暖水种比例提高了7.3%,由45.9%上升到53.2%;浮游植物主要优势种组成趋于简单和小型化,如小型硅藻柔弱拟菱形藻(Pseudonitzschia delicatissima)和细弱海链藻(Thalassiosira subtilis),其平均丰度和优势度显著提高.浮游植物群落的这些年代际分布变异可看作全球气候长期变暖背景下对台湾海峡环境变化的生态学响应迹象.图3表6参34  相似文献   

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Abstract: The need to adapt to climate change has become increasingly apparent, and many believe the practice of biodiversity conservation will need to alter to face this challenge. Conservation organizations are eager to determine how they should adapt their practices to climate change. This involves asking the fundamental question of what adaptation to climate change means. Most studies on climate change and conservation, if they consider adaptation at all, assume it is equivalent to the ability of species to adapt naturally to climate change as stated in Article 2 of the United Nations Framework Convention on Climate Change. Adaptation, however, can refer to an array of activities that range from natural adaptation, at one end of the spectrum, to sustainability science in coupled human and natural systems at the other. Most conservation organizations deal with complex systems in which adaptation to climate change involves making decisions on priorities for biodiversity conservation in the face of dynamic risks and involving the public in these decisions. Discursive methods such as analytic deliberation are useful for integrating scientific knowledge with public perceptions and values, particularly when large uncertainties and risks are involved. The use of scenarios in conservation planning is a useful way to build shared understanding at the science–policy interface. Similarly, boundary organizations—organizations or institutions that bridge different scales or mediate the relationship between science and policy—could prove useful for managing the transdisciplinary nature of adaptation to climate change, providing communication and brokerage services and helping to build adaptive capacity. The fact that some nongovernmental organizations (NGOs) are active across the areas of science, policy, and practice makes them well placed to fulfill this role in integrated assessments of biodiversity conservation and adaptation to climate change.  相似文献   

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