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111.
Caitlin M. Jensen Ellen Hines Barbara A. Holzman Thomas J. Moore Jaime Jahncke Jessica V. Redfern 《Coastal management》2015,43(6):575-588
Shipping traffic poses a worldwide threat to many large whale species. Spatially explicit risk assessments are increasingly being used as a tool to minimize ship-strike risk. These assessments often use static representations of shipping patterns. We used Automatic Identification System data to quantify variability in cargo shipping traffic entering and exiting San Francisco Bay, which contains some of the busiest ports in the United States, at three temporal resolutions: (1) before and after implementation of the California Air Resources Board's Ocean-Going Vessels Fuel Rule, (2) among seasons, and (3) day versus night. We used the nonparametric Mood's Median test to compare median daily distance traveled because the data were not normally distributed and the variance was not homogeneous. Our analyses show that shipping traffic off San Francisco is dynamic at both interannual and daily temporal resolutions, but that traffic was fairly consistent among the seasons considered. Our analyses emphasize the importance of economic and regulatory drivers on interannual shipping traffic patterns. Shipping traffic is expected to continue to change off the U.S. West Coast and to increase globally. These changes in shipping traffic could have implications for the risk of ships striking whales and should be included in risk assessments. 相似文献
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文中系统分析了北部湾港口资源的情况,并分析了北部湾港口资源发展存在核心竞争力不强、“铁路瓶颈”制约、港口自身造血功能差等问题阻碍了港口资源的发展,港口资源需要进行整合。在探讨完港口资源整合具备可行性的基础上,进行了港口资源整合目的、定位、范围和模式等方面的思考,并在此基础上提出北部湾港口资源应该突破瓶颈,做到“六个统一”,走体制创新之路。 相似文献
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Despite its rarity, Dinophysis acuminata is in terms of economic impact, the first toxic algal species along the coasts of Western Europe. It is observed at low levels (< 20 cell l− 1) all the year round but toxic events occur mainly in late spring and summer. D. acuminata ecophysiology is largely unknown due to the inability to culture it. Therefore, standard biomass models based on inorganic nutrition are largely inadequate. Presently, any progress in describing the conditions of population growth of this species will be a step forward to prediction of harmful events at the coast. This species has been observed at increased, albeit low cell densities in retentive eddies located in pycnocline layers. A concentration build-up of one species results from the balance between growth and loss processes, one of the latter being dispersal. The scales of interest for a D. acuminata population are of the order of 10 nautical miles on the horizontal and duration of 10 days, for a reported achievable growth rate of 0.6 day− 1. A three dimensional (3D) hydrodynamical model of the Bay of Biscay has been elaborated to reproduce hydrological structures over the last decade. We attempt here to relate the existence of retentive structures revealed from simulations under realistic forcing conditions and the toxic coastal events recorded in the 10-year time series of the French plankton monitoring network database. The eddies in the coastal area appear to be directly related with the Dinophysis coastal events and they may be a potential effective tool to predict those. 相似文献
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科技攻关在杭州湾跨海大桥建设中的先导作用 总被引:1,自引:0,他引:1
杭州湾跨海大桥工程是一项技术挑战性极强的工程,科技攻关成为建桥成功的关键。概述大桥建设过程中科技管理工作的开展情况,内容包括科技管理工作重点及工作形式,并着重介绍重大科研项目的研究成果。 相似文献
116.
日本东京湾港口群的主要港口职能分工及启示 总被引:2,自引:0,他引:2
由于日本东京湾内港口群职能分工合理,使得狭小的港湾内云集了6个世界级的大型港口,而港口间不但没有形成恶性竞争,反而取得了良好的增长业绩。通过对其职能分工经验进行分析,结合我国环渤海各主要港口的基础与优势,从而提出环渤海各主要港口的职能分工的构想。 相似文献
117.
Sea level and Eddy Kinetic Energy variability in the Bay of Biscay, inferred from satellite altimeter data 总被引:1,自引:0,他引:1
Twelve years (1993–2005) of altimetric data, combining different missions (ERS-1/2, TOPEX/Poseidon, Jason-1 and Envisat), are used to analyse sea level and Eddy Kinetic Energy variability in the Bay of Biscay at different time-scales. A specific processing of coastal data has been applied, to remove erroneous artefacts. Likewise, an optimal interpolation has been used, to create a series of regional Sea Level Anomaly maps, merging data sets from two satellites.The sea level presents a trend of about 2.7 mm/year, which is within the averaged values of sea level rise in the global ocean. Frequency spectra show that the seasonal cycle is the main time-scale affecting the sea level and Eddy Kinetic Energy variability. The maximum sea level occurs in October, whilst the minimum is observed in April. The steric effect is the cause of this annual cycle. The Northern French shelf/slope presents intense variability which is likely due to internal tides. Some areas of the ocean basin are also characterised by intense variability, due to the presence of eddies.The Eddy Kinetic Energy, in turn, is higher from December to May, than during the rest of the year and presents a weak positive trend from April 1995 to April 2005. Several documented mesoscale events, occurring at the end of 1997 and during 1998, are analysed. Altimetry maps prove to be a useful tool to monitor swoddy-like eddies from their birth to their decay, as well as the inflow of seasonal slope water current into the southeastern corner of the Bay of Biscay. 相似文献
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Injuries to natural resources from the release of hazardous substances into aquatic environments have led to hundreds of millions of dollars in compensatory damages awarded under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and other legislation. The institutional mechanisms for negotiating and carrying out the terms of CERCLA natural resource settlements are still in their infancy, and each case has a unique set of injuries, assigned damages, payout schedules, trustee council membership and operating procedures, and environmental conditions and constraints. One of the settlements that has made significant progress toward large‐scale habitat enhancement has occurred in Elliott Bay, a busy, seriously impacted urban harbor in Washington State. The Elliott Bay case is unique among natural resource injury settlements because of the active involvement of two local governments, the City of Seattle, and Metro, who were named as defendants in a lawsuit brought by the National Oceanic and Atmospheric Administration (NOAA) on behalf of the natural resource trustees of Elliott Bay. Both local governments have maintained, and continue to operate, outfalls that discharge into Elliott Bay, and both entities were subject to attempts to recover damages under CERCLA. Following the filing of the lawsuit over injuries to the natural resources of the estuary, alleged to have resulted from the operation of these outfalls, the parties involved negotiated a consent decree settlement. The Elliott Bay/Duwamish Restoration Program has established a process to redress some of the injuries that were attributed to the operation of these outfalls. 相似文献