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71.
72.
The application of magnetic particle technology to environmental remediation has tended to focus, up to now, upon the removal of oil contamination from plumage and fur. The present research demonstrates the potential of this technology to remove oil contamination from the surface of rock. Specifically, a single treatment has been demonstrated to remove more than 80% by weight of heavy bunker oil from the surface of a common foreshore rock type. A further three treatments have been shown to result in an optimum removal of up to 94% by weight. The results are highly reproducible and offer the possibility of achieving up to 100% removal with the appropriate use of pre-conditioners.  相似文献   
73.
The Musquash Estuary, one of the last ecologically intact estuaries in New Brunswick, has been designated an area of interest for a marine protected area (MPA) under the Oceans Act. The area has been assessed for contaminant background levels as required for establishing MPA environmental quality. American lobster (Homarus americanus), blue mussel (Mytilus edulis) and sediments were collected for assessing contaminant levels and distribution in the harbour. Levels of contaminants from the indicator species and the abiotic component have shown: (1) two extremes of high and low Cu and Ag in lobster from the area; and (2) lower metal levels in inner Musquash Harbour sediments and mussels than in those from the harbour mouth. These suggest that deposition of contaminants into the Musquash MPA site was due to transport of contaminants by coastal currents from upstream coastal industrial activities. This reverse trend with higher contaminant levels in the biotic and abiotic components in the outer harbour than in the inner harbour differs from a contaminated harbour and suggests that a contaminant exclusion zone should be considered for controlling contamination from nearby coastal and estuarine industrial sites to protect the sensitive habitats within the marine protected area.  相似文献   
74.
In this study, an updated distribution of Lophelia pertusa between the Porcupine Seabight and Norwegian shelf is presented. It seems unlikely that enigmatic mound structures observed at water depths of more than 570 m during acoustic seabed surveys, particularly to the west of the Shetland Islands, are related to the occurrence of L. pertusa. At these depths in the Faroe-Shetland Channel, the predominant influence of cold Arctic water precludes its growth. Iceberg dumpsites are also considered unlikely explanations for the origin of these mounds, and they are interpreted as most likely to be related to the release of fluids at the seabed. When mound structures were investigated, no scleractinian corals were recovered at water depths >500 m. This study shows the importance of seabed temperature as an environmental control on cold-water coral distribution. The significance of cold-water coral habitats in sustaining high levels of local-scale biodiversity is now becoming apparent in parallel with increased hydrocarbon extraction and fishing activity beyond the shelf edge. There is growing evidence that these areas have been marked by the passage of deep-water trawls. It seems likely that trawling activity has already reduced the extent of cold-water coral distribution in this region of the north-east Atlantic.  相似文献   
75.
Boat harbours are an increasingly common form of artificial habitat. This paper presents a comparative study of contaminants and foulers of a habitat-forming native kelp (Saccharina latissima) in four marinas and four reference locations along the south-west coast of the UK. Fouling of algal laminae was light (<2% cover) in reference locations, while epibiota cover ranged from 25% to 80% of laminae in marinas. Metals associated with antifouling paints were up to six times more concentrated in algal tissues from marinas than from the reference locations. Marinas also carried the greatest cover and diversity of non-indigenous epibiota on the kelp laminae. This indicates not only a potential stress to kelps in these environments, but also the possibility that detached laminae will act as vectors for the dispersal of non-indigenous species. The development of boat harbours creates habitats that are high risk source localities for pollution-tolerant fouling organisms.  相似文献   
76.
引言 英国作为全球主要的海洋国家之一,近年来密集推出了若干重要的海洋战略和研究计划,数量仅次于美国.本文对英国近年来主要的海洋研究战略、计划和项目进行梳理后发现几个特点,即:十分重视海洋研究国家层面的顶层设计;未来海洋研究,十分注重海洋研究基础设施的建设;未来将重点关注海洋酸化、海洋可再生能源开发和海岸带灾害的研究.  相似文献   
77.
Ground-water models: validate or invalidate   总被引:1,自引:0,他引:1  
  相似文献   
78.
刘燕飞  王金平  高峰 《海洋科学》2017,41(12):17-25
利用数据分析工具Thomson Data Analyzer(TDA)和网络分析工具UCINET对SCIE文献数据库2007–2016年国际深海研究文献数据进行计量分析,以期揭示国际深海研究的现状、趋势和热点分布。研究结果表明:(1)国际深海研究论文在近十年来持续增长,英国、美国、法国和德国在深海研究领域的学术影响力最强,其中美国处于研究合作核心地位。(2)中国科学院、俄罗斯科学院和美国伍兹霍尔海洋研究所等是主要的发文机构,其中伍兹霍尔海洋研究所处于研究合作核心地位。(3)与国际深海研究联系最紧密的学科领域包括海洋与淡水生物学、海洋学、地球科学综合、生态学等。(4)深海研究的热点分布在深海生物多样性研究、深海营养环境研究、海底无脊椎动物研究,以及海底有孔虫类和食物网分析研究。(5)中国在深海领域的研究发展迅速,但国际影响力较为欠缺。未来,中国需要加强该领域气候变化、海洋生物等方向的研究,并借助高水平的国际合作,进一步提升国家和机构在深海研究方面的国际影响力。  相似文献   
79.
西藏羌塘盆地是公认的天然气水合物有利找矿区,钻探取心是鉴别天然气水合物最直接、最准确的手段。为满足天然气水合物钻探需求,制定了大直径取心、低温泥浆护心的技术方案。试制了跟管取心钻具和大直径绳索取心钻具;逐步完善低温泥浆配方;研制出新型高效泥浆冷却装置。在鸭湖地区天然气水合物调查井施工中,克服地层复杂、环境恶劣等难题,完成钻探取样施工,终孔深度700.70 m,岩心采取率满足地质要求。查明了地层岩性、冻土厚度、气源、岩石物性特征等,不仅为天然气水合物资源评价也为其他油气资源调查提供了地质资料、技术支撑和人才储备。  相似文献   
80.
河流水系连通性机制及计算方法综述   总被引:1,自引:0,他引:1       下载免费PDF全文
河流水系连通性具有水文调蓄、保障生物迁徙通畅、改善水土环境等功能,目前主要从水文、景观和生态等方面对其进行了定义,而河流水系连通性对社会发展也发挥着重要作用,故河流水系连通性具有自然和社会双重属性,其连通性机制主要表现为纵向、横向、垂向连通性。目前主要从景观学、水文学、水力学、生态学等学科角度提出了图论法、水文-水力学法、景观法、生物法和综合指标法等计算方法,各方法有其适用性和不足,应用中须针对实际问题选择适宜方法或进行修正。河流水系连通性未来研究应综合多尺度、多领域、多学科,在研究内容上,重点开展尺度协同、连通性含义界定、响应机理及修复问题研究,在研究手段上,重点开展多方法、多技术集成问题研究。  相似文献   
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