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101.
Individuals, businesses, and policymakers face the problem of selecting a preferred strategy for adapting a managed ecosystem to future climate change when there is risk and/or uncertainty about future climate change and its ecosystem impacts, and the conditional outcomes of adaptive strategies (i.e., performance of an adaptive strategy given a particular future climate change scenario occurs). Evaluation methods for this purpose are described for two cases; one in which the decision-maker can (climate risk case) and cannot (climate uncertainty case) assign probabilities to future climate change scenarios. Fuzzy sets are used to characterize uncertainty regarding both future climate change, and the conditional outcomes of adaptive strategies. The preferred conditional adaptive strategy for a future climate change scenario is determined by ordering the adaptive strategies for that scenario using a fuzzy set operation. Two methods are described for determining the adaptive strategy that is preferred across all climate change scenarios. The preferred overall adaptive strategy for the climate risk case is determined by maximizing a performance index for strategies. The preferred overall adaptive strategy for the climate uncertainty case is determined using the minimax regret criterion, which selects the strategy that minimizes the maximum loss in performance that can occur across all strategies and climate change scenarios. Ways for making the evaluation methods dynamic are considered.  相似文献   
102.
103.
Vézina F  Speakman JR  Williams TD 《Ecology》2006,87(10):2447-2458
Marked interindividual variation in metabolic rate suggests considerable complexity in energy management strategies, but attempts to further our understanding of the relationship between resting metabolic rate (RMR), daily energy expenditure (DEE), and reproductive effort have been hampered by the complexity of studying this system in the field. Here, we describe energy management strategies in a captive-breeding system, using Zebra Finches (Taeniopygia guttata), to demonstrate the high level of complexity and interindividual variability in energy expenditure, food intake, locomotor activity, and reproductive effort. In particular, we investigated whether the increase in RMR associated with egg production is additive, resulting in higher DEE and a need for elevated food intake, or whether this cost is compensated by reduced expenditure in nonreproductive components of the energy budget. We found high levels of intra-individual variation in energy expenditure associated with egg production in female Zebra Finches, e.g., comparing nonbreeding stage with the one-egg stage, change in RMR varied from 4.0% and 41.3%, and change in DEE varied from -33.3% to +46.4%. This variation was systematically related to aspects of locomotor activity and reproductive effort. Females with the largest increase in RMR during egg production decreased locomotor activity the most but still had increased DEE at the one-egg stage, and females with high DEE at the one-egg stage produced larger clutches. Our study suggests that females minimize increases in DEE during egg production through behavioral energy reallocation (reduced locomotor activity) but that individuals differ in their use of this strategy, which, in turn, is related to the absolute level of reproductive investment. This suggests a very complex, individually variable system of energy management to meet the demands of egg production.  相似文献   
104.
The coverage of strategic environmental assessment (SEA) has been extended to all public sector policies, plans and programmes subject to Scottish jurisdiction. Evaluation of the arguments advanced by the Scottish Executive for using environmental assessment as a tool for environmental governance requires an exploration of some of the contested interpretations of the function of environmental assessment at a strategic level. The paper examines the implications of this extension of the European Union SEA Directive in the context of current arrangements to fit environmental assessment into the UK tradition of integrated policy appraisal. It considers the methodological implications of using SEA explicitly for improving public sector decision making at all levels and across all activities. This enables environmental effects to be taken into account at an early stage in the formulation of government policy, through a transparent system of assessment which encourages public participation.  相似文献   
105.
In recent years, the so-called ‘resource curse’ syndrome has gained increasing currency. Growing evidence suggests that many African countries with significant natural wealth have actually reaped limited rewards, instead experiencing underdevelopment, corruption, political instability, and in some cases, violent conflict. In the small West African state of Sierra Leone, it has been suggested that diamonds played a key role in fuelling a brutal civil war during the 1990s, an issue that has given rise to a burgeoning literature on ‘blood diamonds’. However, as Sierra Leone emerges from a decade of destruction, other research suggests that diamonds could actually provide the impetus for post-war reconstruction. This paper explores the role of alluvial diamond mining in post-conflict Sierra Leone, focusing on two communities in the Eastern Province that were badly affected by the war. Drawing on field-based research conducted between 2002 and 2007, the paper considers the diamond mining situation in the context of broader development strategies in post-conflict reconstruction. It is argued that sustainable development can only be achieved if future policies are based on a detailed understanding of relationships between diamond mining and rural development at local, regional and national levels.  相似文献   
106.
Under the United States Oil Pollution Act of 1990, natural resource trustees are charged with assessing natural resource impacts due to an oil spill and determining the type and amount of natural resource restoration that will compensate the public for the impacts. Habitat equivalency analysis is a technique through which the impacts due to the spill and the benefits of restoration are quantified; both are quantified as habitat resources and associated ecological services. The goal of the analysis is to determine the amount of restoration such that the services lost are offset by services provided by restoration. In this paper, we first describe the habitat equivalency analysis framework. We then present an oil spill case from coastal Louisiana, USA, where the framework was applied to quantify resource impacts and determine the scale of restoration. In the Louisiana case, the trustees assessed impacts for oiled salt marsh and direct mortality to finfish, shellfish, and birds. The restoration project required planting salt-marsh vegetation in dredge material that was deposited on a barrier island. Using the habitat equivalency analysis framework, it was determined that 7.5 ha of the dredge platform should be planted as salt marsh. The planted hectares will benefit another 15.9 ha through vegetative spreading resulting in a total of 23.4 ha that will be enhanced or restored as compensation for the natural resource impacts.  相似文献   
107.
Female kentish plovers Charadrius alexandrinus typically desert their broods after the chicks hatch, i.e. 1–4 weeks before the chicks fledge or become independent. In this paper we investigate the costs and benefits of desertion for females. Desertion incurs a cost for females: following desertion chick survival in broods is lower (0.95 +- 0.02 day–1) than before the female deserts (0.98 +- 0.01 day–1). We investigated several possible causes for reduced brood survival by comparing characteristics of broods before and after desertion (controlling for differences in brood age). After desertion males increased the time they spent foraging and they tended to reduce time spent brooding chicks. Increased mortality of chicks may occur in deserted broods because following desertion (1) males spend less time alert in vigilance behaviour than before desertion, (2) they attend the chicks from greater distances, and (3) they show greater distraction display distances (in response to human intruders). Growth or development of chicks, measured by weight gain and tarsus length, was not different before and after desertion. Females gain two potential benefits from desertion: (1) they may remate and produce a second brood within the same breeding season or (2) they may enhance their probability of surviving to breed in a subsequent season. At least 27% of female kentish plovers that deserted remated and renested in the same season in this study. In contrast, we found no evidence that brood desertion increased the survival of females: there was no difference in local survival rate (return rate) for females deserting before or after 6 days brood age. These results clearly demonstrate that female kentish plovers that desert their offspring prior to fledging incur costs, but we suggest that there is a trade-off with the potential benefits gained by remating and making a second breeding attempt in the same season.  相似文献   
108.
The evaluation of microbial responses to three in situ source removal remedial technologies—permanganate‐based in situ chemical oxidation (ISCO), six‐phase heating (SPH), and steam injection (SI)—was performed at Cape Canaveral Air Station in Florida. The investigation stemmed from concerns that treatment processes could have a variety of effects on the indigenous biological activity, including reduced biodegradation rates and a long‐term disruption of community structure with respect to the stimulation of TCE (trichloroethylene) degraders. The investigation focused on the quantity of phospholipid fatty acids (PLFAs) and its distribution to determine the immediate effect of each remedial technology on microbial abundance and community structure, and to establish how rapidly the microbial communities recovered. Comprehensive spatial and temporal PLFA screening data suggested that the technology applications did not significantly alter the site's microbial community structure. The ISCO was the only technology found to stimulate microbial abundance; however, the biomass returned to predemonstration values shortly after treatment ended. In general, no significant change in the microbial community composition was observed in the SPH or SI treatment areas, and even small changes returned to near initial conditions after the demonstrations. © 2004 Wiley Periodicals, Inc.  相似文献   
109.
In selecting six keywords from the environmental discourse the authors argue that language's 'double motivation' reveals a dialectical structure through which it simultaneously expresses both a utopian narrative and an ideologically driven myth of totality and consensus. The ambiguity of these keywords is of critical significance to all those involved in the environmental discourse, for without agreement on the meaning of commonly used concepts effective policy development is potentially disabled. The keywords we explore are 'community', 'sustainability', 'globalisation', 'diversity', 'democracy' and 'environment' itself.  相似文献   
110.
The Abt study of forty-one mostly Fortune 200 nonservice firms forms a new picture of environmental management. We present data indicating that environmental management is becoming central to corporate strategy and is being managed as an arena of competition rather than as a compliance-driven function. We look at environmental management's new role through four lenses: its relationship to strategic planning; its evolving management structures that show environment increasingly integrated into the main functions of the business; innovation in corporate environmental investments reflecting new drivers beyond compliance; and new management systems and measures of firm-wide performance that demonstrate that environment is being seen increasingly as an arena of competitive concern. We argue that much of the change is driven by three realities. First, as customers integrate environmental values into their conceptions of product quality, they are buying more products with identifiably environmental attributes. This change translates environmental management, historically a cost center, into a potential source of sales revenue, a change which cannot be underestimated. Second, recent life-threatening damage to the global ecosystem and atmosphere reframes environmental management. This moves firms toward a systemic and global approach matched to the globalization of competitive and market concerns, and it places environmental management in the strategic sphere. And third, pollution prevention in its cross-fertilization with total quality management is driving firms to focus on managing environment as an integral part of product management, and is helping them to reassess environmental performance as a contributor to productivity and innovation.  相似文献   
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