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241.
Compensatory mitigation of impacted streams and wetlands has increased over the past two decades, with the associated industry spending over US$2.9 billion in aquatic restoration annually. Despite these expenditures, evaluations by the National Research Council and U.S. Government Accountability Office have provided evidence that compensatory mitigation practices are failing to protect aquatic resource functions and services, and vague federal policy and inadequate evaluation of compensatory mitigation projects are to blame. To address these weaknesses, an update to federal regulations on compensatory mitigation was released in 2008. Additionally, the 2012 Reissuance of Nationwide Permits, some of which affects compensatory stream mitigation, was recently published. Current policy, as reflected in these documents, still uses nonspecific language to direct compensatory stream mitigation leaving most implementation decisions to the local U.S. Army Corps of Engineers district. The majority of federal mitigation policy has focused on wetland compensation, with other aquatic resources receiving less attention (e.g., streams). In this article, weaknesses of current policy are discussed, as are suggested policy changes to minimize the loss of stream ecosystem functions and services. Compensatory mitigation policy should clearly define key terms, incorporate adaptive management procedures, and provide guidelines for determining mitigation costs and compensation ratio requirements.  相似文献   
242.
The Climate Change Act 2008 commits the UK to reducing carbon emissions by 80% of 1990 levels by 2050. With household emissions constituting more than a quarter of current total energy use in the UK, energy practices in the home have taken on increased policy attention. In this paper, we argue that the UK government's approach is founded upon a variant of methodological individualism that assumes that providing greater energy information to individuals will effect behaviour change in relation to energy use. Such an approach is potentially limited in its effectiveness and does not afford appropriate recognition to all those affected by energy policy. In contrast to this approach, we set out an alternative perspective, a community knowledge networks approach to energy and justice which recognises the contexts and relationships in which people live and use energy. Such an approach emphasises situated knowledge and practices in order to gain a greater understanding of how individuals and communities use energy, but, importantly, offers a means for affording greater recognitional justice to different social groups.  相似文献   
243.
Studies in Europe have reported negative effects of acid deposition on forest birds, and research in North America has identified links between forest bird abundance and rates of acid deposition. We examined the bird community in an acidified forest in central Pennsylvania (USA) and evaluated the effects of terrestrial lime application on birds. We used a before-after control-impact (BACI) study design, with one year of observation before (2003) and three years after lime application (2004, 2005, and 2006). Between the 2003 and 2004 field seasons, 4500 kg/ha of dolomitic lime were applied to two of four 100-ha watersheds. Each year, we monitored bird abundance and Ovenbird (Seiurus aurocapilla) eggshell thickness and territory size. Soil and snail abundance data were also collected. The bird community and territory size results indicated that the study area may be providing low-quality habitat for forest birds, perhaps as a result of acid deposition. We found lower forest bird abundances than have been found in less acidified areas of Pennsylvania, and larger Ovenbird territory sizes than have been found in other studies. We found a significant positive relationship between soil calcium and bird abundance, indicating that soil calcium may affect bird abundance. Liming increased soil calcium and pH and led to increased snail and bird abundances. After liming, bird abundance was positively related to snail abundance. No significant changes occurred in Ovenbird territory size or eggshell thickness. Our results suggest that acid deposition could be responsible for reduced bird abundance, and that liming is a potential mitigation technique.  相似文献   
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Birth dates from almost 3 million babies born between 1969 and 2005 in Switzerland were analyzed for the weekday of birth. As in other countries but with unprecedented amplitude, a very marked non-random distribution was discovered with decreasing numbers of births on weekends, reaching -17.9% in 2005. While most of this weekend births avoidance rate is due to fewer births on Sundays (up to -21.7%), the downward trend is primarily a consequence of decreasing births on Saturdays (up to -14.5%). For 2005, these percentages mean that 3,728 fewer babies are born during weekends than could be expected from equal distribution. Most interestingly and surprisingly, weekend birth-avoiding rates are significantly correlated with birth numbers (r = 0.86), i.e. the lower the birth number per year, the lower the number of weekend births. The increasing avoidance of births during weekends is discussed as being a consequence of increasing numbers of caesarean sections and elective labor induction, which in Switzerland reach 29.2 and 20.5%, respectively, in 2004. This hypothesis is supported by the observation that both primary and secondary caesarean sections are significantly correlated with weekend birth avoidance rates. It is therefore likely that financial aspects of hospitals are a factor determining the avoidance of weekend births by increasing the numbers of caesarean sections.  相似文献   
247.
The benefits of utilizing intermediaries to broker understanding between environmental scientists and policy makers have become widely touted. Yet little is known about the tasks boundary spanners undertake to develop environmental policy solutions and how these tasks fit into frameworks intended to advance public policy decision making. Such frameworks may be constructed to aid decision makers in differentiating between the types of environmental policy issues that confront them or the policy settings in which they are operating. Consequently, this paper examines how six different knowledge brokering strategies; informing, consulting, matchmaking, engaging, collaborating and building capacity might be employed in responding to different types of environmental policy problems or policy settings identified in decision aiding frameworks. Using real world examples, four frameworks are reviewed. They are; Lindquist's [Lindquist, E.A., 1988. What do decision models tell us about information use? Knowledge in Society 1 (2), 86–111; Lindquist, E.A., 1990. The third community, policy inquiry, and social scientists. In: Stephen Brooks, S., Gagnon, A. (Eds.), Social Scientists, Policy and the State. Praeger, New York; Lindquist, E.A., 2001. Discerning policy influence: framework for a strategic evaluation of IDRC-Supported research] decision regimes, Turnhout et al.’s [Turnhout, E., Hisschemoller, M., Eijsackers, H., 2007. Ecological indicators: between the two fires of science and policy. Ecological Indicators 7 (2), 215–228] science policy typology, Holling's [Holling, C.S., 1995. What barriers? What bridges? In: Gunderson, L.H., Holling, C.S. (Eds.), Barriers and Bridges to the Renewal of Ecosystems and Institutions. Columbia University Press, New York, pp. 3–34] adaptive cycle and Kurtz and Snowden's [Kurtz, C.F., Snowden, D.J., 2003. The new dynamics of strategy: sense-making in a complex and complicated world. IBM Systems Journal 42 (3), 462–483] Cynefin domains. For the different problem types or policy settings described in the decision aiding frameworks primary knowledge brokering strategies are identified. While the frameworks differ in their conceptual constructions, the applicability of specific knowledge brokering strategies serve as a commonality across particular problem types and policy settings.  相似文献   
248.
The Regional Greenhouse Gas Initiative for the northeastern states of the U.S. allows for terrestrial carbon (C) sequestration offsets generated by afforestation activities only. This paper estimates the maximum potential quantity and associated costs of increasing the storage of carbon by afforestation of existing agricultural land in the 11 states of the Northeast United States. The focus of the work was to describe location, the quantity, and at what cost it would be economically attractive to shift agricultural production to afforestation to increase carbon storage in the region. Widely available data sets were used to (1) identify spatially-explicit areas for lower costs carbon offsets and (2) estimate carbon supply curves related to afforestation of agricultural land over three time periods (10, 20, and 40 years). Carbon accumulation and total carbon offset project costs were estimated at a county scale and combined to identify expected costs per ton of carbon dioxide equivalents (CO2e). Large variation in estimated costs per ton of CO2e are driven by varying carbon accumulation potentials and opportunity costs of taking land out of agricultural production, as well as the duration of the project activity. Results show that the lowest cost carbon offset projects will be in certain counties of Maine, Vermont, and New York. Pasture land, with lower opportunity costs, generally presents the opportunity for lower cost carbon offset projects relative to cropland. This analysis estimates that afforestation of pasture land in the northeast will not become economically attractive until the price rises above 10 per metric tonne (MT) CO < sub > 2 < /sub > e and that up to 583 million MT could be economically sequestered if the price were to rise to10 per metric tonne (MT) CO2e and that up to 583 million MT could be economically sequestered if the price were to rise to 50 per MT CO2e, based on a 40-year project life. With regard to cropland in the northeast, afforestation does not become economically advantageous for land owners until the price rises above $40 per MT CO2e. It is estimated that up to 487,000 MT could be sequestered from cropland if the price were to rise to $40 per MT CO2e. It is estimated that up to 487,000 MT could be sequestered from cropland if the price were to rise to 50 per MT CO2e, based on a 40-year project life.  相似文献   
249.
After briefly reviewing key resilience engineering perspectives and summarising some green infrastructure (GI) tools, we present the contributions that GI can make to enhancing urban resilience and maintaining critical system functionality across complex integrated social–ecological and technical systems. We then examine five key challenges for the effective implementation of GI that include (1) standards; (2) regulation; (3) socio-economic factors; (4) financeability; and (5) innovation. We highlight ways in which these challenges are being dealt with around the world, particularly through the use of approaches that are both context appropriate and socially inclusive. Although progress surmounting these challenges has been made, more needs to be done to ensure that GI approaches are inclusive and appropriate and feature equally alongside more traditional ‘grey’ infrastructure in the future of urban resilience planning. This research was undertaken for the Resilience Shift initiative to shift the approach to resilience in practice for critical infrastructure sectors. The programme aims to help practitioners involved in critical infrastructure to make decisions differently, contributing to a safer and better world.  相似文献   
250.
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