Evidence for microbiological manganese oxidation in the river Tamar Estuary, South West England

Water samples from the Tamar Estuary oxidized manganese when supplemented with Mn²⁺ (2 mgl⁻¹). The rates of oxidation were depressed in the presence of various metabolic inhibitors. The effect of Mn²⁺ and temperature on the rate of manganese oxidation suggested that a biological process was largely responsible for converting Mn²⁺ to Mn⁴⁺. Rates of manganese oxidation were much higher in freshwater (3·32 μgl⁻¹ h⁻¹ in water containing 30 mgl⁻¹ of suspended matter) than in saline water (0·7 μgl⁻¹ h⁻¹ in water of salinity 32‰) containing the same amount of particulate matter. The rate of manganese oxidation was proportional to the particulate load (up to 100 mgl⁻¹ particulates).     

Maritime clusters in diverse regional contexts: The case of Canada

This paper presents the main results of a project on Canada's regional clusters in the maritime industry. The objectives of this paper are twofold: firstly, the driving forces and the development processes of the different maritime clusters in Canada are described. Secondly, the role of cluster policy in promoting maritime competitiveness in Canada and the key institutional and geographic barriers that affect their growth and development are discussed. The empirical work consists of analyses and assessment of three clusters in different provinces in Canada: Quebec, Newfoundland and Labrador, and British Columbia.     

The UNEP/GEF South China Sea Project: Lessons learnt in regional cooperation

The UNEP/GEF project entitled “Reversing environmental degradation trends in the South China Sea and Gulf of Thailand” implemented by United Nations Environment Programme (UNEP) in partnership with seven riparian states bordering the South China Sea was initiated in 2002 and completed in 2008. The project was complex since it addressed three priority areas of concern identified in the Transboundary Diagnostic Analysis namely the loss and degradation of coastal habitats, over-exploitation of fisheries, and land-based pollution. The fourth component of the project was concerned with regional co-ordination including facilitation of national level execution and securing inter-country agreement on project related matters. A number of lessons learnt from implementing the project include, inter alia: the need for a well designed management framework to ensure smooth co-ordination and information exchanges among and within participating countries; the importance of individuals in terms of the success or failure of Inter-Ministry Committees at the national level; separation of scientific and technical issues from political decision-making; the importance of the demonstration site network in encouraging cooperation at the local level; ownership of the project by participating countries; strong involvement of regional and national experts in implementing project tasks; linkages between habitat and fisheries management for developing a regional fisheries refugia network; sharing data through the development of regional databases; productive services of the project coordinating unit; and development of a framework for long-term cooperation in environment management.     

Solving complex fisheries management problems: What the EU can learn from the Nordic experiences of reduction of discards

A crucial issue for the new EU common fisheries policy is how to solve the discard problem. Through a study of the institutional set up and the arrangements for solving the discard problem in Denmark, the Faroe Islands, Iceland and Norway, the article identifies the discard problem as related to both natural, other material and to cultural conditions. Hence, solving the discard problem requires not only technical and regulatory instruments, but also arenas and structures that allow and facilitate processes of cultural change.     

Gravel bedforms in the West Solent, Southern England

Data is presented on distinctive gravel bedforms which occur in the tidal marine environment of the west Solent in Southern England. Discrete zones of gravel waves of different sizes and flat bed gravel occur in similar depths and hydrodynamic conditions. In the absence of comparable field data the conclusions are related to flume data: a purely physical explanation is not obvious and requires more detailed hydrodynamic data. It is considered that other factors such as availability of mobile sediment and biological accretion may be important influences.     

Gravel bedforms in the West Solent,Southern England

Data is presented on distinctive gravel bedforms which occur in the tidal marine environment of the west Solent in Southern England. Discrete zones of gravel waves of different sizes and flat bed gravel occur in similar depths and hydrodynamic conditions. In the absence of comparable field data the conclusions are related to flume data: a purely physical explanation is not obvious and requires more detailed hydrodynamic data. It is considered that other factors such as availability of mobile sediment and biological accretion may be important influences.     

经略大西洋:从区域化到全球化海洋战略

经略大西洋是着眼未来、建设海洋强国的战略抉择,更是我国海洋战略从区域化走向全球化的未来趋势。文章阐述全球化时代国际海洋秩序的变革以及各国相应的海洋战略调整,分析大西洋的重要历史地位与现实战略意义,并从地理位置、海上贸易、航运安全和海洋资源开发等角度探讨大西洋对我国的战略价值;基于北极航道的逐步开通,进一步分析未来经略大西洋的契机;在此基础上开展我国对大西洋的战略考量,提出现阶段可以把经济与贸易合作、海洋秩序维护以及科考与资源开发保护作为我国战略的优先选项。     

Heat exchanges in muddy intertidal sediments: Chichester Harbour,West Sussex,England

Temperature observations made from a lightweight tower assembly in Chichester Harbour, West Sussex, demonstrate that marked changes in temperature at intertidal mud surfaces occur on a flow tide. The magnitude and direction of these changes are dependent on the external atmospheric and marine conditions, and on the timing of tidal inundation. Calculated heat exchange values for the 3h prior to high water fall into four distinct timing zones. There is a relationship between thermal stress, measured as rate of change of temperature with time, and time of high water. Mud surfaces are net receivers of heat energy from inundating water layers.     

“21世纪海上丝绸之路”建设对我国南海地区的影响分析

"21世纪海上丝绸之路"是我国在新时期提出的重大战略举措,我国南海地区作为"21世纪海上丝绸之路"的起点海域和战略基点,同时也作为连接我国与东南亚、南亚以及非洲与欧洲的桥梁,在这一战略中扮演着举足轻重的角色。文章立足于"21世纪海上丝绸之路"的丰富内涵并结合南海地区的历史发展脉络和开发利用现状,分别从地理位置、资源保护与开发、海洋经济繁荣与发展、地区安全稳定和国家海洋战略5个方面,分析"21世纪海上丝绸之路"建设对我国南海地区的影响:1强化南海地区"桥梁与枢纽作用";2促进南海地区海洋"资源宝库"保护与开发;3推动南海地区海洋经济发展与繁荣;4维护南海地区周边地区安全与稳定;5提升南海地区在国家海洋战略中的地位。南海地区必将在新时期我国建设海洋强国的潮流中大放异彩。     

Large-scale offshore sand extraction: What could be the results of interaction between model and decision process?

The Netherlands is considering large-scale offshore sand extraction to meet the increasing demand for building sand, as the current supply of sand from land is insufficient. To develop a well-considered management policy to address this problem, knowledge about future morphological changes offshore caused by such an extraction is necessary. Such knowledge is not yet available. To support decisions about large-scale sand extraction, we developed a morphological model, which indicates possible effects of such extraction. However, because no field data is available, we cannot meet the requirement of decision makers to validate this model. Therefore, its results are controversial and difficult to use in decision-making. In this study, firstly we evaluate whether validation of the model would help the decision-making process about large-scale sand extraction? Secondly, we explore how we can use the invalidated model results in decision-making. And finally, we explore how to improve both the model and the use of the model without validation.Our opinion is that validation of the model will not solve the problem that decision makers deal with, and that although invalidated, decision makers can use the model results by using them as early warning signals. Interviews with the key players, to define the willingness to use the model results for decision-making, lead to useful recommendations to improve the model. These interviews were the first step of constructive technology assessment (CTA), which focuses on broadening the design and implementation process to stimulate the integration of societal criteria in the development of the model. Besides, these interviews appeared to have a positive influence on the willingness of the key players to use the model for decision-making. In general, we conclude that CTA, modulating the interaction between model and decision process, is a useful method for model makers that can help to make their models useful tools for decision-making.     

Alkalinity titration in seawater: How accurately can the data be fitted by an equilibrium model?

Displaying “calculated minus observed” data for precise titrations of seawater with strong acid permits direct evaluation of important parameters and detection of systematic errors.At least two data sets from the GEOSECS (Geochemical Ocean Sections) program fit an equilibrium model (which includes carbonate, borate, sulfate, silicate, fluoride, and phosphate) within the most stringent experimental error, less than 2 μmol kg⁻¹. The effect of various parameters on the fit of calculated to observed values depends strongly on pH. Although standard potential E₀, total alkalinity A_t, total carbonate C_t, and first acidity constant of carbon dioxide pK₁ are nearly independent, and can be determined for each data set, other parameters are strongly correlated. Within such groups, all but one parameter must be determined from data other than the titration curve.Adding an acid-base pair to the theoretical model (e.g. C_x=20 μmol kg⁻¹, pK_x=6.2) produces a deviation approaching 20 μmol kg⁻¹ at constant C_t; however, adjustment of C_t by about −18 μmol kg⁻¹ to produce a good fit leaves only ± 1.5 μmol kg⁻¹ residual deviation from the reference values. Thus, at current standards of precision, an unidentified weak acid cannot be distinguished from carbonate purely on the basis of the titration curve shape.There are few full sets of numerical data published, and most show larger systematic errors (3–12 μmol l⁻¹) than the above; one well-defined source is experiments performed in unsealed vessels. Total carbonate can be explicitly obtained as a function of pH by a rearrangement of the titration curve equation; this can reveal a systematic decrease in C_t in the pH range 5–6, as a result of CO₂ gas loss from the titration vessel. Attempts to compensate for this by adjustment of A_t, C_t, or pK₁ produce deviations which mimic those produced by an additional acid-base pair.Changing from the free H⁺ scale (for which [HSO₄⁻] and [HF] are explicit terms in the alkalinity) to the seawater scale (SWS) (where those terms are part of a constant factor multiplying [H⁺]) requires modification of the titration curve equation as well as adjustment of acidity constants. Even with this change, however, omission of pH-dependent terms in [HSO₄⁻] and [HF] produces small systematic errors at low pH.Shifts in liquid junction potential also introduce small systematic errors, but are significant only at pH <3. High-pH errors due to response of the glass electrode to Na⁺ as well as H⁺ can be adequately compensated to pH 9.5 by a linear selectivity expression.     

Unreported bycatch in the New Zealand West Coast South Island hoki fishery

There are recognised benefits to managing fisheries by individual transferable quotas (ITQs), but ITQs may increase incentives to discard fish.     

Tidal observations on the West Coast,South Island,New Zealand

Harmonic tidal constants, calculated from sea surface elevation observations at Jackson Bay on the West Coast of the South Island, are consistent with available semi‐diurnal and diurnal tidal phase distributions. Current observations taken over a 111 day period at mid‐depth in 1505 m of water on the southern flank of the Challenger Plateau and over a 240 day period in 1430 m of water on the South Island western coast continental slope, are subject to tidal analysis. At both sites there is a component of energy flux directed across the isobaths and only at the northern site for the M2 tide is the phase consistent with a dominant progressive barotropic tide. The successive 30 day harmonic constants at the southern continental slope site exhibit a trend in the M2 tidal ellipse speed and ellipticity suggesting the presence of a regular internal tide. Superposition of ‘internal tidal’ and barotropic tidal flows, as prescribed from progressive‐ and standing‐wave elevations, to fit the observations indicates that the ‘internal tide’ is probably associated with the first baroclinic mode. At the current‐meter depths the speeds of the ‘internal tide’ for the M2 tide are about the same as the barotropic speeds, whereas, the S2 ‘internal tide’ speeds are larger than those of the barotropic tide. The consistency of the trend in ellipse parameters lends support to the theoretical progressive trapped barotropic tidal flows being a good approximation to the actual barotropic tide. Some support for the hypothesis that the S2 tide on the West Coast of New Zealand has a substantial standing wave contribution is given by the northern observations, where the ratio of the S2: M2 internal tidal ellipse current amplitudes are substantially larger than the ratio of the elevations, the internal tide being generated by across‐isobath flows.     

Accumulation of uranium in sediments and phosphorites on the South West African shelf

Organic-rich sediments and coexisting phosphorites from the continental shelf off South West Africa have been analysed for uranium and thiorum by alpha-spectrometry. The uranium concentrations in the sediments range from 10 to 55 ppm, with an isotopic composition close to that of sea-water, indicating that uranium is passing into the sediments at the present time. The phosphorites occur in the sediments as thin unconsolidated laminae and as lithified nodules and pellets, with uranium contents ranging from 79 to 158 ppm. Based on the uranium isotopic composition, only the unconsolidated phosphorite laminae are recent, while the lithified nodules and pellets, with ²³⁴U/²³⁸U and ²³⁰Th/²³⁴U ratios close to radio-active equilibrium, appear to be inherited from a previous period of phosphorite deposition. Deposition of uranium appears to take place predominantly by incorporation into carbonate fluorapatite growing authigenically within the sediment. Uranium accumulation rates, computed from ¹⁴C-dated sections of the sediment cores, and using only uranium values with modern isotopic composition, range from 232 to 765 μg/cm² per 1,000 years. These results stress the importance of organic-rich sediments containing authigenic phosphorite beneath areas of high organic productivity as a major sink for uranium in the ocean.     

A method of age determination for the South West African pilchard Sardinops ocellata

A method of age determination, based on recent research on growth and ring formation, is described for the pilchard of South West Africa. Dates of ring formation from 1971 to 1981 are documented. Illustrated examples of otolith interpretations are given.     

海警视域下的海上安全威胁及应对策略

当前海警机构在海上遂行任务时面临多种形式的海上安全威胁,除常规安全威胁外,以海上军事冲突威胁和海上恐怖主义威胁为代表的非常规安全威胁正使海警面临越发严峻的海上综合实战能力考验。文章通过对海警视域下海上安全威胁的综合分析,提出提升装备体系化建设水平、增强人员实战化训练效果和探索海警多能化发展模式等应对策略,以期为海警未来妥善应对各类海上安全威胁及风险挑战提供有益参考。     

逐步建立与市场经济相适应的海域使用管理框架

《中华人民共和国海域使用管理法》施行以来,各级海洋行政主管部门坚持依法行政,积极开展工作,在海洋功能区划、海域权属、海域有偿使用等各项制度建设方面都取得了较大的进展,逐步形成了职能明确、层次清晰的海域使用管理框架。当前,随着我国社会主义市场经济体制的完善以及行政管理体制改革的深化,各级海洋行政管理机构进一步转变政府职能、改进管理方式,朝着行为规范、运转高效的行政管理体制转变。在这种背景下,有必要研究和探讨市场经济条件下海域使用管理的主体、职能定位和管理内容,并通过管理实践逐步形成结构合理、配置科学、程序…     

CoastLearn: Lessons learnt from a web-based capacity building in Integrated Coastal Zone Management (ICZM)

The capacity building initiatives for the Integrated Coastal Zone Management (ICZM) intend to create, in a worldwide perspective, a capable critical mass. CoastLearn is one of such outstanding efforts. Through the application of questionnaires to students and to the course coordinator, in addition to its website information, positive features and also aspects that can be improved were recognized. This paper aims at establishing some statements and providing recommendations about aspects to be considered by ICZM capacity building efforts. The outstanding recommendations are the development of feedback policy, the creation of online tutors and discussion forums, always considering the attendants' needs.