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831.
Mariana M. P. B. Fuentes Lynda Chambers Andrew Chin Peter Dann Kirstin Dobbs Helene Marsh Elvira S. Poloczanska Kim Maison Malcolm Turner Robert L. Pressey 《Mitigation and Adaptation Strategies for Global Change》2016,21(2):209-224
Management of marine mega-fauna in a changing climate is constrained by a series of uncertainties, often related to climate change projections, ecological responses, and the effectiveness of strategies in alleviating climate change impacts. Uncertainties can be reduced over time through adaptive management. Adaptive management is a framework for resource conservation that promotes iterative learning-based decision making. To successfully implement the adaptive management cycle, different steps (planning, designing, learning and adjusting) need to be systematically implemented to inform earlier steps in an iterative way. Despite the critical role that adaptive management is likely to play in addressing the impacts of climate change on marine mega-fauna few managers have successfully implemented an adaptive management approach. We discuss the approaches necessary to implement each step of an adaptive management cycle to manage marine mega-fauna in a changing climate, highlighting the steps that require further attention to fully implement the process. Examples of sharks and rays (Selachimorpha and Batoidea) on the Great Barrier Reef and little penguins, Eudyptula minor, in south-eastern Australia are used as case studies. We found that successful implementation of the full adaptive management cycle to marine mega-fauna needs managers and researchers to: (1) obtain a better understanding of the capacity of species to adapt to climate change to inform the planning step; (2) identify strategies to directly address impacts in the marine environment to inform the designing step; and (3) develop systematic evaluation and monitoring programs to inform the learning step. Further, legislation needs to flexible to allow for management to respond. 相似文献
832.
Carole Di Poi Lauris Evariste Alexis Séguin Antoine Mottier Julie Pedelucq Jean-Marc Lebel Antoine Serpentini Hélène Budzinski Katherine Costil 《Environmental science and pollution research international》2016,23(6):5002-5018
The bioconcentration potential of fluoxetine (FLX) and its biological effects were investigated in juvenile Pacific oyster exposed for 28 days to environmentally relevant concentrations of FLX (1 ng L?1, 100 ng L?1 and up to 10 μg L?1). FLX bioaccumulated in oyster flesh resulting in 28-day bioconcentration factors greater than 2,000 and 10,000 by referring to wet and dry weights, respectively. Nevertheless, FLX did not induce oyster mortality, delayed gametogenesis, or lead to adverse histopathological alterations. At the two highest concentrations, despite non-optimal trophic conditions, FLX stimulated shell growth but only in a transient manner, suggesting a role of serotonin in the regulation of feeding and metabolism in bivalves. Those high concentrations seemed to drive bell-shaped responses of catalase and glutathione S-transferase activities throughout the exposure period, which may indicate the activation of antioxidant enzyme synthesis and then an enhanced catabolic rate or direct inhibition of those enzymes. However, no clear oxidative stress was detected because no strong differences in thiobarbituric acid-reactive substance (TBARS) content (i.e. lipid peroxidation) were observed between oyster groups, suggesting that cellular defence mechanisms were effective. These results demonstrate the importance of considering additional biomarkers of oxidative stress to obtain a comprehensive overview of the FLX-induced changes in marine bivalves exposed under realistic conditions. Considering the battery of biomarkers used, FLX appears to induce little or no effects on oyster physiology even at a concentration of 10 μg L?1. These results do not confirm the lowest observed effect concentration (LOEC) values reported by some authors in other mollusc species. 相似文献
833.
Stéphane Roujol Robert Joumard 《Atmospheric environment (Oxford, England : 1994)》2009,43(5):1008-1014
The impact of the auxiliaries and particularly air conditioning on emissions (CO2, CO, HC, NOx and particles) is investigated. To this aim, various data from European laboratories are used and analysed. Parameters linked to technology and to climatic conditions are investigated. The main distinction is made between gasoline and diesel vehicles. A physical model is proposed to extrapolate the excess emissions at low temperature (below 28 °C) and with solar radiation, together with a statistical model. 相似文献
834.
Retreat and advance of shoreline position occurs naturally, and also as a result of defences which are constructed to prevent
erosion and flooding. Retreat more commonly manifests itself down-drift of defences due to a sediment deficit causing the
coast to become ‘set-back’. Advance normally develops due to sediment accumulation up-drift of a barrier inhibiting longshore
drift, resulting in the coast becoming ‘set-forward’. Many examples of set-backs and set-forwards are recorded, but their
location, number and cause is not known on a national scale. Using the Futurecoast aerial photographs, approximately 200 localities
were identified as set-back or set-forward in England and Wales, with half situated in the Eastern and South East regions
of England. Half of the total set-backs or set-forwards were on cliffed coasts, and half on low-lying coasts. Without local
knowledge it is difficult to distinguish between set-backs and set-forwards. Set-backs often indicate higher retreat rates,
thus threatening cliff-top infrastructure which requires defence upgrade and extensions, as well as raising maintenance costs.
Monitoring set-backs is important for shoreline management, because as retreat continues, set-backs evolve and artificial
headlands form and grow. This is reinforced by the shift from hard defence policies towards softer engineering approaches,
managed realignment and limited intervention. 相似文献
835.
Maria João Cruz Elisabeth Maria Rogier Robert Tiago Costa David Avelar Rui Rebelo Mário Pulquério 《Regional Environmental Change》2016,16(5):1293-1304
Assessing biodiversity vulnerability to future climate change is essential for developing robust adaptation strategies. A number of vulnerability assessment methodologies have been developed, from bioclimatic envelop models to more complex approaches that also consider biological traits and population status. However, the lack of comparative studies leaves the user to choose among the different methodologies without much guidance. This study applied three vulnerability assessment approaches to the Portuguese herpetofauna: (I) impact assessment approach based on bioclimatic models; (II) integrated vulnerability assessment approach, adding the evaluation of adaptive capacity to approach I; and (III) integrated vulnerability assessment and validation based on expert consultation. Results showed disagreement between the different approaches for 19 % of the species studied. Most differences were found between approach III and the two other approaches. All approaches showed advantages and limitations, the choice of a methodology being ultimately dependent on the study goals. Approach I has proven efficient to capture general vulnerability patterns. Approach II, although presenting results similar to approach I, allows for the identification of key factors affecting the species adaptive capacity and may be useful in tailoring adaptation measures. Approach III further allows us to identify knowledge gaps and to evaluate vulnerability when data availability or quality is reduced. Further, because this approach is based on an expert workshop, it has proven a perfect means to build on the vulnerability assessment results to identify indicator species and prioritize specific adaptation options. 相似文献
836.
All U.S. federal agencies administering environmental laws purport to practice adaptive management (AM), but little is known about how they actually implement this conservation tool. A gap between the theory and practice of AM is revealed in judicial decisions reviewing agency adaptive management plans. We analyzed all U.S. federal court opinions published through 1 January 2015 to identify the agency AM practices courts found most deficient. The shortcomings included lack of clear objectives and processes, monitoring thresholds, and defined actions triggered by thresholds. This trio of agency shortcuts around critical, iterative steps characterizes what we call AM‐lite. Passive AM differs from active AM in its relative lack of management interventions through experimental strategies. In contrast, AM‐lite is a distinctive form of passive AM that fails to provide for the iterative steps necessary to learn from management. Courts have developed a sophisticated understanding of AM and often offer instructive rather than merely critical opinions. The role of the judiciary is limited by agency discretion under U.S. administrative law. But courts have overturned some agency AM‐lite practices and insisted on more rigorous analyses to ensure that the promised benefits of structured learning and fine‐tuned management have a reasonable likelihood of occurring. Nonetheless, there remains a mismatch in U.S. administrative law between the flexibility demanded by adaptive management and the legal objectives of transparency, public participation, and finality. 相似文献
837.
838.
Mert Guney Robert P. Chapuis Gerald J. Zagury 《Environmental science and pollution research international》2016,23(24):24422-24434
Human exposure to particulate matter (PM) has been associated with adverse health effects. While inhalation exposure to airborne PM is a prominent research subject, exposure to PM of geological origin (i.e., generated from soil/soil-like material) has received less attention. This review discusses the contaminants in PM of geological origin and their relevance for human exposure and then evaluates lung bioaccessibility assessment methods and their use. PM of geological origin can contain toxic elements as well as organic contaminants. Observed/predicted PM lung clearance times are long, which may lead to prolonged contact with lung environment. Thus, certain exposure scenarios warrant the use of in vitro bioaccessibility testing to predict lung bioavailability. Limited research is available on lung bioaccessibility test development and test application to PM of geological origin. For in vitro tests, test parameter variation between different studies and concerns about physiological relevance indicate a crucial need for test method standardization and comparison with relevant animal data. Research is recommended on (1) developing robust in vitro lung bioaccessibility methods, (2) assessing bioaccessibility of various contaminants (especially polycyclic aromatic hydrocarbons (PAHs)) in PM of diverse origin (surface soils, mine tailings, etc.), and (3) risk characterization to determine relative importance of exposure to PM of geological origin. 相似文献
839.
Modeling freshwater fish distributions using multiscale landscape data: A case study of six narrow range endemics 总被引:1,自引:0,他引:1
Species distribution models (SDMs) have become integral tools in scientific research and conservation planning. Despite progress in the assessment of various statistical models for use in SDMs, little has been done in way of evaluating appropriate ecological models. In this paper, we evaluate the multiscale filter framework as a suitable theoretical model for predicting freshwater fish distributions in the upper Green River system (Ohio River drainage), USA. The spatial distributions of six fishes with contrasting biogeographies were modeled using boosted regression trees and multiscale landscape data. Species biogeography did not appear to affect predictive performance and all models performed well statistically with receiver operating characteristic area under the curve (AUC) ranging from 0.87 to 0.98. Predictive maps show accurate estimations of ranges for five of six species based on historical collections. The relative influence of each type of environmental feature and spatial scale varied markedly with between species. A hierarchical effect was detected for narrowly distributed species. These species were highly influenced by soil composition at larger spatial scales and land use/land cover (LULC) patterns at more proximal scales. Conversely, LULC pattern was the most influential feature for widely distributed at all spatial scales. Using multiscale data capable of capturing hierarchical landscape influences allowed production of accurate predictive models and provided further insight into factors controlling freshwater fish distributions. 相似文献
840.