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1.
Abstract

The West Coast Groundfish Trawl Catch Share Program was designed to achieve multiple economic goals and objectives, including increasing net benefits, profitability, flexibility, and utilization of harvest allocations. In this article, we leverage seven years of comprehensive cost and earnings data to evaluate progress towards these goals with a focus on harvesters. Our assessment shows that five years post-implementation, net benefits to the nation have doubled, and indicators of productivity and profitability have increased. The fleet that targets Pacific whiting has seen the largest gains, due in part to increases in total allowable catch and the elimination of the race-to-fish. However, increased revenues have not been realized to the degree that was expected for harvesters targeting non-whiting groundfish, partly due to lower than predicted consolidation and relatively low quota utilization. Economic outcomes indicate that tradeoffs exist between certain objectives of the program, specifically between achieving full utilization and flexibility for harvesters. Results are discussed in the context of the design and evaluation of catch share programs for diverse, multispecies fisheries.  相似文献   
2.
The North Norfolk coast is a naturally eroding coastline that has been subject to various management strategies over time, many of which have impeded its natural evolution. The Kelling to Lowestoft-Ness Shoreline Management Plan underpins management of the North Norfolk coast, advocating policies of managed realignment and no active intervention for much of this coastline. Implementation of these policies would give rise to significant loss of housing in North Norfolk during the course of this century. This has caused intense conflict between local communities and coastal planners, with the former feeling abandoned to the vagaries of natural coastal processes. Coastal planners need to work closely with local communities to implement a long-term vision for a sustainable coast. The issues of conflicting land-use planning policies and compensation for affected communities must be addressed. The wider implications of current management strategies are not fully understood and may, in some cases, be unsustainable.  相似文献   
3.
Abstract

Fishery management measures often aim to regulate harvesting behavior but can have downstream effects on fish processors, output markets, and consumers. Empirical analysis of these impacts is generally limited due to data availability. In this article, we utilize census costs and earnings data to examine operational characteristics and economic outcomes for shorebased processors before and after implementation of the West Coast Groundfish Trawl Catch Share Program. While the overall number of buyers of catch share species along the coast decreased and fish input prices generally increased, patterns in outcomes were different for processors with Pacific whiting operations compared to those that produce nonwhiting groundfish, including lengthened seasonal whiting operations but a decrease in the number of days receiving nonwhiting groundfish. These differences in outcomes illustrate the complexities involved in the management of multispecies fisheries with heterogeneous participants in both the harvest and post-harvest sectors. This review contributes to the fairly limited empirical work on the fish processing sector, which is an integral part of the seafood supply chain and important to the economic resilience of coastal fishing communities.  相似文献   
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Methane (CH4) concentrations were measured in the water column, in sediment porewaters, and in atmospheric air, in the Ría de Vigo, NW Spain, during both the onset (April 2003) and at the end of (September 2004) seasonal upwelling. In addition, CH4 concentration and stable isotopic signatures (δ13CH4) were measured in porewaters, and sediment methanogenesis and aerobic oxidation of CH4 were determined in sediment incubations. Surface water column CH4 (2 m depth) was in the range 3–180 nmol l− 1 (110–8500% saturation) and followed a generally landward increase but with localised maxima in both the inner and middle Ría. These maxima were consistent with CH4 inputs from underlying porewaters in which CH4 concentrations were up to 3 orders of magnitude higher (maximum 350 μmol l− 1). Surface water CH4 concentrations were approximately three times higher in September than in April, consistent with a significant benthic CH4 flux driven by enhanced sediment methanogenesis following the summer productivity maximum. CH4 and δ13CH4 in sediment porewaters and in incubated sediment slurries (20 °C) revealed significant sediment CH4 oxidation, with an apparent isotopic fractionation factor (rc) of  1.004. Using turbulent diffusion models of air–sea exchange we estimate an annual emission of atmospheric CH4 from the Ría de Vigo of 18–44 × 106 g (1.1–2.7 × 106 mol). This estimate is approximately 1–2 orders of magnitude lower than a previous estimate based on a bubble transport model.  相似文献   
6.
This paper analyzes some of the changes that took place in the structure of energy use for passenger travel in industrialized countries. Data is presented on energy use and travel activity for the four major modes of travel — automobile, bus, rail and air — for eight OECD countries: the United States, Japan, the United Kingdom, West Germany, France, Italy, Sweden, and Norway. We use the Laspeyres and Divisia indices to analyze the causes of the change in energy use between 1970 and 1987. The total change in energy use for travel is explained by changes in domestic passenger transport volumes, the mix of modes of travel, and the energy intensities of each mode. We have found two important effects that have a fundamental impact on energy use for travel since 1970. First, shifts among modes of transport towards more energy-intensive ones and large increases in volumes of travel (measured in passenger-kilometers) increased energy use for travel in many OECD countries, often more rapidly than the overall growth in GDP. Second, energy intensities, measured in mJ/passenger-kilometer, of passenger transport fell only in a few countries between 1970 and 1987. Even though individual automobiles have become more energy-efficient, greater size, power, and weight, worsening traffic conditions in Japan and Europe, and fewer people in cars restrained or even offset efficiency improvements. Particularly notable are the increases in intensities in Japan and Germany. The most important exception to this trend was the United States, but the intensities of land-based travel remain higher there than in most other countries. These findings lead to a pessimistic outlook for future energy use for travel. After all, if little or no energy was saved during the decades of high fuel prices, what can be expected in the 1990s?  相似文献   
7.
Abstract

Catch share programs can have far-reaching effects on coastal communities and the people that rely on fishing income, including crew members. Analysis of management actions affecting crew wages and well-being is often limited due to a dearth of available data. We examine crew-related outcomes during the first six years of the West Coast Groundfish Trawl Catch Share Program using two unique datasets – a mandatory economic survey and a voluntary social science study. We find that impacts on crew compensation differ from other catch share programs due to prior conditions of the fishery and also vary by the target species within the program. The median number of crew positions per vessel increased slightly, annual crew days decreased, and crew wage as a percentage of revenue was nearly unchanged, even with the introduction of new costs. Median daily crew compensation increased from $514 per day to $776 after implementation of catch shares and annual compensation increased from $33 thousand to $39 thousand. Many crew members expressed a lack of support for the program and job satisfaction did not rise with increased wages and fewer days at sea, indicating that job satisfaction is likely influenced by more than compensation and effort.  相似文献   
8.
The fundamental objective of the Container Security Initiative (CSI) is to engage both so-called 'mega-ports' (ports sending the highest volume of ocean going container traffic into the US) and the national governments where these ports are located in a way that will facilitate the pre-screening of outbound containers destined to the US. The emerging issue of security as a key factor in global supply chains can be perceived as inconsistent with the objective of facilitating international trade (Dulbecco and Laporte, 2003). However, this perception does not stand up to analysis. Security is an evident part of the mainstream supply-chain paradigm while security can also become a driver for trade facilitation. The purpose of this paper is therefore to discuss the impact of the US CSI on maritime supply chains. The first section will mostly be related to the issue of security and supply chains while the second section will investigate CSI and its impact while exploring some of the financing implications of the security initiative.  相似文献   
9.
Abstract

This paper presents a review of time-series analysis of road safety trends, aggregated at a national level, which has been performed in the period 2000–12 and applied to European national data sets covering long time periods. It provides a guideline and set of best practices in the area of time-series modelling and identifies the latest methods and applications of national road safety trend analysis in Europe. The paper begins with the methodological framework adopted for aggregate time-series modelling that will be considered, and then discusses a number of relevant applications to long-period data aggregated at the national level, whether for countries alone, or for groups of countries. Some analyses, which were performed at the disaggregated level, are also provided, as they are being used more and more. Finally, the paper summarizes and discusses the significant changes in aggregate road safety trend analysis which occurred during the period and provides recommendations for continuing these research efforts.  相似文献   
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