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161.
We conducted a survey of 3321 Forest Service employees involved in compliance with the National Environmental Policy Act (NEPA) followed by five focus groups to investigate agency views of the purpose of agency NEPA processes and their appropriate measures of success. Results suggest the lack of a unified critical task for Forest Service NEPA processes and that employees' functions relevant to NEPA influence their views of its meaning. Compared to other agency personnel, members of interdisciplinary teams who carry out most day-to-day NEPA-related tasks placed greater emphasis on minimizing negative environmental and social impacts, satisfying multiple stakeholders and avoiding litigation and appeals. Line officers, who typically serve as the decision makers following NEPA processes, placed greatest emphasis on efficient implementation and least emphasis on minimizing impacts. Advisory personnel placed greatest emphasis on effective disclosure of analyses and decision-making. We discuss the structural origins of these differences as well as their implications.  相似文献   
162.
Collaboration is a growing trend in agency-led natural resource management in the USA, carrying the promise of defusing conflict and incorporating a broader range of stakeholder ideas. However, concerns exist that confrontational or litigious groups may use collaborative forums to their organization's own advantage. We conducted case studies on three collaboratives to understand how these efforts have influenced the behavior of environmental groups who were previously at odds with the managing agency, the US Forest Service. Results suggest that trust between boundary spanners from historically adversarial groups can support a realignment of the accountabilities they feel. As rational, affinitive, and procedural trust developed, boundary spanners began to advocate, within their home organizations, for the collaborative's goals. Key activities driving these realignments included the development of fair and transparent procedures governing the collaborative group, structured interaction designed to build consensus, and planned informal interactions that revealed shared values among collaborative participants.  相似文献   
163.
Prenatal ultrasound and magnetic resonance imaging (MRI) demonstrated a large oropharyngeal tumor, and cardiac and cranial abnormalities consistent with neurofibromatosis type 1 (NF1) in a third-trimester fetus, which were confirmed on postmortem examination. Sonographic features of NF1 are generally nonspecific; MR examination provided significant additional information, facilitating prenatal diagnosis. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
164.
Adaptive management (AM) is a rigorous approach to implementing, monitoring, and evaluating actions, so as to learn and adjust those actions. Existing AM projects are at risk from climate change, and current AM guidance does not provide adequate methods to deal with this risk. Climate change adaptation (CCA) is an approach to plan and implement actions to reduce risks from climate variability and climate change, and to exploit beneficial opportunities. AM projects could be made more resilient to extreme climate events by applying the principles and procedures of CCA. To test this idea, we analyze the effects of extreme climatic events on five existing AM projects focused on ecosystem restoration and species recovery, in the Russian, Trinity, Okanagan, Platte, and Missouri River Basins. We examine these five case studies together to generate insights on how integrating CCA principles and practices into their design and implementation could improve their sustainability, despite significant technical and institutional challenges, particularly at larger scales. Although climate change brings substantial risks to AM projects, it may also provide opportunities, including creating new habitats, increasing the ability to quickly test flow‐habitat hypotheses, stimulating improvements in watershed management and water conservation, expanding the use of real‐time tools for flow management, and catalyzing creative application of CCA principles and procedures.  相似文献   
165.
This special issue contributes to scholarly debates about the role of cities in global climate governance, reflecting on the promise, limits, and politics of cities as agents of change. It takes an empirically-informed approach drawing on multiple diverse geographical and political contexts. Overall, the special issue aims to stimulate reflection and debate about where understanding and practice needs improvement to advance the role of cities in global climate governance. Key questions that are addressed in the special issue include: To what extent do real world experiences confirm or disconfirm the high expectations of cities as agents and sites of change in addressing global climate change as expressed in urban climate governance literature? In what ways do internal political dynamics of cities enable or constrain urban climate governance? How is climate governance in cities enabled and constrained by interactions with broader governance levels? In what ways can climate governance in cities be advanced through critical attention to the previous issues?  相似文献   
166.
Natural resource planning processes on public lands in the United States are driven in large part by the requirements of the National Environmental Policy Act (NEPA), which dictates general processes for analyzing and disclosing the likely impacts of proposed actions. The outcomes of these processes are the result of multiple factors, many related to the manifold smaller incremental decisions made by agency personnel directing the processes. Through interviews with decision makers, team leaders, and team members on five NEPA processes within the U.S. Forest Service, this study examines those incremental decisions. Risk, in particular external relationship risk, emerged as a dominant lens through which agency personnel weigh and make process-related decisions. We discuss the tradeoffs associated with agency actors’ emphasis on this form of risk and their potential implications for adaptive ecosystem management and organizational performance.  相似文献   
167.
It is obvious that the application of solid waste compost improves the soil fertility. These wastes, however, may also have some negative effects on the agricultural environment due to their metal content. This research aimed at evaluating the influence of Tunisian municipal solid waste compost and farmyard manure on some chemical properties and the distribution of heavy metals in a calcareous Tunisian soil (clayey–loamy soil). A field plot experiment, without vegetation, was installed since 1999 at the experimental farm of the Agronomic National Institute of Tunis (INAT) in the region of Mornag (20 km south of Tunis, Tunisia). During 5 years, the field received yearly the following treatments: 0, 40, 80 and 120 t/ha of municipal solid waste compost and 0, 40 and 120 t/ha of manure. The fractionation of heavy metals in the soil was evaluated after 5 years using a sequential extraction procedure. The application of the two amendments was found to increase the content of organic matter, the total nitrogen content and the electrical conductivity, whereas it slightly decreased the soil pH. The addition of manure did not have a significant effect on the accumulation of heavy metals in the soil, whereas compost application increased the total concentration of heavy metals in the soil. The distribution of heavy metals between the different fractions in untreated and treated soils showed the residual fraction to be dominant, followed by the fraction bound to Fe and Mn oxides. The amount of Cu bound to the organic fraction increased with the application rate, which is probably caused by the formation of organic complexes. For the other metals, the increase of the association with organic matter is very limited. The application of compost moreover increases the amount of Zn associated with Fe and Mn oxides. The “Mobility Factor (MF)” was quite low and did not change after the 5-year application of the two organic amendments. It always remained lower than 10%, although for Cd it amounted to 17%.  相似文献   
168.
The road transport system in Lebanon is one of the most unsustainable in the Middle East region due to, in large part, the absence of a national transportation strategy. This study proposes mitigation measures based on Lebanon’s commitments for reducing fossil fuel use and CO2 emissions from road transport by increasing the share of fuel-efficient and hybrid electric vehicles and increasing the utilization of the existing bus service. Results show that increasing the market share of fuel-efficient vehicles to 35% in 2040 stabilizes energy use and emissions. The addition of hybrid vehicles to the first strategy, with a target of 10% market share by 2040, leads to 11% additional savings. Increasing the share of bus passenger kilometers traveled to 45% in 2040 leads to a reversal of adverse impacts. A combined strategy of all three measures leads to 63% reductions in 2040 compared to 2010, which is even superior to their cumulative savings.  相似文献   
169.
Predation and competition are important biotic interactions influencing populations and communities in marine soft sediments. Sea stars are ubiquitous predators with diverse diets that play functionally important roles in the benthos. In this study, we examined the diet and the ecological roles of three sympatric species of the genus Astropecten (A. aranciacus, A. irregularis pentacanthus and A. platyacanthus). The study was performed between March 2010 and February 2011 on the Maresme coast (northwestern Mediterranean Sea). Results showed that their main diet consisted on gastropods and bivalves, such as Glycymeris glycymeris, Callista chione, Gibbula guttadauri and Cyclope neritea. Food competition between species was avoided by partition of prey resources. Intraspecific differences in the dietary compositions between seasons were found, but not between size classes. Ontogenetic patterns of prey size consumption were recognized in the three species. A large diet overlap was detected between A. aranciacus and A. platyacanthus in winter, due to changes in prey availability. Nevertheless, the analysis of the infaunal community composition and stomach contents indicated that food selection was not associated with prey availability.  相似文献   
170.
The Hawaiian hawksbill population has fewer than 20 females nesting per year; hence, there is a need to monitor this population closely and basic biological information on individual growth and age to maturity is critical. We present a skeletochronology analysis of Hawaiian hawksbills using humeri recovered from 30 dead stranded hawksbills, plus 10 dead hatchlings. Growth mark morphology shows readily distinguishable marks similar in appearance to other species, though some animals displayed more diffuse marks. Growth rates remained high (average 2.24–4.77 cm year?1) from 20 to 80 cm straight carapace length (SCL). Hawksbills larger than 80 cm SCL had average growth rates of 0.3 cm year?1. There were few adult turtles in the sample; however, results indicate hawksbills have faster growth rates than loggerhead or green turtles, with probable average age to maturity (at size 78.6 cm SCL) occurring between 17 and 22 years.  相似文献   
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