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1.
JIN Xianglong 《海洋学报(英文版)》2013,32(12):1-3
In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future. 相似文献
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Size-fractionated uranium isotopes in surface waters in the Jiulong Estuary in China 总被引：1，自引：1，他引：0
L&#; E ZHANG Lei CHEN Min QIU Yusheng XING N YANG Weifeng LI Yanping HUANG Yipu 《海洋学报(英文版)》2008,27(1):29-41
Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium （ 〈 0.4 μm） exis- ted in the low molecular mass fraction （ 〈 10 000 u）, and the colloidal uranium-238 （10 000 u -0.4 μm） only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases （ 〉 0.4 μm）, the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows： 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows ： 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value （1.0）. The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic 相似文献
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Much of the recent Canadian activity in marine technology has focused on development of capabilities in Arctic waters, and on the update and replacement of naval vessels. This paper describes some of the significant projects and programs now under way, and suggests future research and development requirements. 相似文献
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In order to investigate factors controlling nutrient cycling in the shallow and turbid coastal ecosystem of Galveston Bay, data from: (1) the Texas Water Commission (TWC) database 1980–1989, and (2) salinity transects in 1989 and 1993 are presented and analyzed. Statistical regression and time-series analysis were carried out on data acquired by TWC between 1980 and 1989, in an attempt to establish seasonally of nutrient and chlorophyll-a (chl.-a.) concentrations in the bay and to determine factors which regulate these concentrations.A strong seasonality was found for phosphorus and chl.-a. in the upper and mid-bay stations. A recurring maximum for phosphate occurred in September and a chl.-a. maximum occurred regularly in March–April. It is hypothesized that benthic regeneration of phosphorus at the end of summer is responsible for the phosphate maximum. The inverse correlation of the partition coefficient (Kd) for phosphate with the concentration of suspended particulate matter (SPM), coupled to a strong enrichment of phosphate in suspended particles at low SPM concentrations, indicates additional control by geochemical and physical processes such as particle sorting and/or particle-colloid interactions. Nitrate is inversely correlated with salinity at the upper and mid-bay stations, indicating the Trinity River is a major source.Nutrient concentrations in the lower bay (East and West Bay stations) are considerably lower and less predictable, as they are not correlated with salinity or temperature. Data from the 1989 and 1993 transects confirm the yearly maximum in phosphate concentration in late summer months, with peak concentrations in the upper Trinity Bay. It is concluded that despite possible phosphate buffering by physical and geochemical mechanisms, relatively large concentration maxima recur regularly every year during the summer, possibly caused by a benthic source of phosphate. 相似文献
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中国科学院海洋研究所建所70年来，在海洋贝类分类学研究领域取得了长足发展与进步，做出一系列开创性研究成果。本文综述了建所以来我所海洋腹足类分类学研究方面的主要进展，概述了取得的主要科研成果，分析了现代腹足类分类学研究的发展趋势以及面临的挑战，并对今后的发展提出了相应对策和建议。 相似文献
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九龙江口红树林区底栖动物体内的多环芳烃 总被引：9，自引：0，他引：9
2001年8月和11月在九龙江口红树林区采集了6种底栖动物,测定了它们体内16种多环芳烃的含量.紫游螺(Neritina [Dostia] violacea)、黑口滨螺(Littoraria melanostoma)、可口革囊星虫(Phascolosoma esculenta)、弹涂鱼(Periophthalmus cantonensis)、查加拟蟹守螺(Cerithideadj adjariensis)、孔虾虎鱼(Trypauchen vagina)对沉积物中多环芳烃的富集系数均小于1.弹涂鱼和黑口滨螺体内多环芳烃的含量有随沉积物中多环芳烃含量的增加而增加的趋势,但它们的富集系数却有随沉积物中多环芳烃含量增加而减少的趋势.弹涂鱼、黑口滨螺、查加拟蟹守螺和可口革囊星虫体内多环芳烃主要由二环多环芳烃组成,紫游螺和孔虾虎鱼体内分别是四环和五环多环芳烃比例最高. 相似文献
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M. E. Waite M. J. Waldock J. E. Thain D. J. Smith S. M. Milton 《Marine environmental research》1991,32(1-4)
In 1986 the Government of the United Kingdom (UK) introduced legislation to control the sale of tribytltin (TBT)-based paints. From 1986 to 1989 monitoring was undertaken, whereby samples of water, sediment, oysters (Crassostrea gigas) and mussels (Mytilus edulis) were collected from six estuaries and water samples from five marinas/harbours, and analysed for TBT. In 1989 the concentrations of TBT in water, oysters and mussels were generally only one-third to one-quarter of those observed in 1986. The most marked decrease in concentrations of TBT in oysters and mussels occurred in 1987–1988, following the 1987 ban on the use of TBT-based paints on small boats and mariculture equipment. As the concentrations of TBT in oyster tissues had decreased there has been improvement in oyster growth in terms of both meat production and growth of thin (i.e. normally shaped) shells. Oysters with a normal shell shape can now be grown in five of the six estuaries which were monitored. In contrast to the reduction in concentrations of TBT noted in water and bivalves, changes in concentrations of TBT in sediments showed no clear trend from 1986 to 1989. 相似文献
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《Marine Policy》2013
Marine environment protection in Europe faces a number of challenges. One is the coordination of relevant sectoral policies — such as agricultural and fisheries policies — with regard to marine protection objectives. The question in the following is on how marine protection issues can be more closely integrated in sectoral policies under the conditions prevailing at present. In particular the strength and weaknesses of the Marine Strategy Framework Directive (MSFD) as the key instrument for marine environment protection in Europe are analyzed in this context. In particular, the MSFD does not adequately address all sectors and policies which are relevant to marine environment protection. One possible means of giving the MSFD greater influences on other policies of relevance to marine waters is to integrate the objectives established under the MSFD in the European maritime policy. The aim should be to require the further development of sectoral policies to take unrestricted account of the objectives of the MSFD implementation process. But also other instruments of marine policy such as maritime spatial planning and marine protected areas are crucial to advance the protection of European seas. 相似文献
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《Deep Sea Research Part I: Oceanographic Research Papers》1999,46(8):1391-1415
The biomass, species and chemical composition of the mesozooplankton and their impact on lower food levels were estimated along a transect across the Arctic Ocean. Mesozooplankton biomass in the upper 200 m of the water column was significantly higher (19–42 mg DW m-3) than has previously been reported for the Arctic Ocean, and it reached a maximum at ca. 87°N in the Amundsen Basin. The lowest values were recorded in the Chukchi Sea and Nansen Basin, where ice cover was lower (50–80%) than in the central Arctic Ocean. In the deeper strata (200–500 m) of the Canadian and Eurasian Basins, the biomass was always much lower (4.35–16.44 mg DW m-3). The C/N (g/g) ratio for the mesozooplankton population was high (6.5–8.5) but within the documented range. These high values (when compared to 4.5 at lower latitudes) may be explained by the high lipid content. Mesozooplankton accounted for approximately 40% of the total particulate organic carbon in the upper 100 m of the water column. Mesozooplankton species composition was homogeneous along the transect, consisting mainly of copepods (70–90% of the total number). It was dominated by four large copepod species (Calanus hyperboreus, C. glacialis, C. finmarchicus and Metridia longa), which together accounted for more than 80% of the total biomass. According to measurements of gut pigment and gut turnover rates, the mesozooplankton on average ingested between 6 and 30% of their body carbon per day as phytoplankton. Microzooplankton may have provided an additional source of energy for the mesozooplankton community. These data emphasize the importance of mesozooplankton in the arctic food web and reinforce the idea that the Arctic Ocean should no longer be considered to be a “biological desert”. 相似文献
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Gubanova D. P. Vinogradova A. A. Iordanskii M. A. Skorokhod A. I. 《Izvestiya Atmospheric and Oceanic Physics》2021,57(3):297-309
Izvestiya, Atmospheric and Oceanic Physics - The results of an intensive complex experiment carried out from March 25 to May 3, 2020, to study the composition and time variability of urban aerosol... 相似文献
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对一氧化氮在浮游植物中的研究进展进行了归纳,总结了一氧化氮对浮游植物生长的影响,探讨了浮游植物中一氧化氮的产生机制,并对今后的研究重点提出展望。 相似文献
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Managing overcapacity in small-scale fisheries in Southeast Asia 总被引：3，自引：0，他引：3
Robert S. Pomeroy 《Marine Policy》2012,36(2):520-527
It is now almost universally accepted that most of the nearshore fisheries in Southeast Asia are overfished. It is also accepted that overcapacity is one of the leading causes of this overfishing. The problem of addressing overcapacity in small-scale fisheries in Southeast Asia is much more complex than that of reducing overcapacity in industrial fleets. In order to manage capacity, managers need to measure and understand how much capacity currently exists in the fishery and what is the desirable level of capacity that best meets the set of management objectives. The only feasible solution to overcapacity may be based on a coordinated and integrated approach involving a mixed strategy of resource management, resource restoration and conservation, livelihoods and economic and community development, and restructured governance arrangements. The reduction of overcapacity implies an increased focus on people-related solutions and on communities. 相似文献
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利用微滤和超滤技术研究了九龙江河口区表层水中铀及其同位素组成的粒级分布和地球化学行为.结果表明,溶解态(<0.4μm)中低分子量组分(<10 000 u)占主要份额,胶体态(10 000 u~0.4μm)238U所占比例不足1%,且随盐度的增加其所占份额逐渐降低.溶解态、低分子量组分和胶体态238U的比活度与盐度之间存在良好的线性正相关关系,证实它们在九龙江河口区呈现保守行为.在颗粒态(>0.4μm)中,各粒级组分238U所占份额主要受控于相应颗粒物的浓度,在盐度小于20的区域,各粒级颗粒组分238U占颗粒态的份额有如下变化次序:10~53μm>2~10μm>0.4~2μm>大于53μm,而在盐度大于30的近外海站位,该次序发生一些变化:0.4~2μm>10~53μm>2~10μm>大于53μm,最小粒级颗粒组分238U的贡献有所增加,反映了自生铀贡献的加强.九龙江河口区表层水中溶解态(包括低分子量组分和胶体态)的234U/238U)A.R.均大于1,显示出234U过剩的特征,而各粒级颗粒组分中的234U/238U)A.R.则接近于平衡值(1.0).这一现象与陆地岩石风化过程中水体对铀的淋滤释出量及234U的优先浸出有关.对232Th/238U质量比的研究显示,溶解态及其所包括的低分子量组分和胶体态的232Th/238U质量比均小于1,而颗粒态及其所包括的4个粒级组分中的232Th/238U质量比均大于1,反映了向外海输送过程中铀、钍地球化学行为的差异. 相似文献
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台湾海峡西部海域软质海底多毛类的生态 总被引：2，自引：0，他引：2
本文根据１９８４－１９８５年４航次底栖生物调查资料，首次全面地研究了台湾海峡西部海域多毛类的种类组成，数量分布及其与环境因子的关系。结果表明，该海域多毛类４０４种，习见种１９１种，区系属亚热带性质；平均生物量４．３３ｇ／ｍ＾２，平均栖息密度６８个／ｍ＾２；有沿岸性和外洋性两种明显不同的生态类型，前者位于沿岸水系常年控制海域，种类多，数量较大，后者位于南部粗粒沉积物分布区，种类较少；多毛类高数量区与 相似文献
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Fisheries development in northeastern Asia in conjunction with changes in climate and social systems
The status and prospects of fisheries in northeastern Asia are reviewed in conjunction with climate change and social issues. This region has the biggest yield, consumption, and international trade of fisheries products in the world. Due to increasing industrialization and greenhouse gas emissions, higher rates of warming have occurred. The impacts of climate change on fisheries could be detrimental because the main fishery products are small pelagic fish whose biomass fluctuations are sensitive to climate changes. Improvements in the economies of the nations in this region offset the demand for fish products in human diets, and employment in fisheries. It is recommended that fisheries management plans consider both changes in climate and in social systems. Stocks which migrate between national jurisdictions are in need of particular attention. 相似文献
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A brief review of the studies performed by Russian scientists in dynamic meteorology in 2003–2006 is presented. This review is based on the material prepared by the Commission on Dynamic Meteorology of the National Geophysical Committee of the Russian Academy of Sciences and included in the general information report of the Section of Meteorology and Atmospheric Sciences at the 24th General Assembly of the International Union of Geodesy and Geophysics. 相似文献