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1.
Our global oceans are threatened by climate change, overfishing, pollution and a growing list of other impacts that demonstrate an urgent global need for sustainable ocean management. Whilst marine conservation initiatives and protected ocean spaces have increased over recent years, ocean management still lags behind the terrestrial sectors in incorporating and involving communities in its development. ‘Social licence to operate’ is used broadly across the terrestrial literature, but its understanding and application within the marine has been limited to date. This review sought to collate and synthesise instances of social licence in the marine realm as documented in the literature, aiming to create an understanding that may inform future research and development of social licence. Its results determine that social licence is yet an emergent concept in the marine sector but there may be great potential for its application in the marine context. Social licence has become an important theme for development in marine industry and resource use, particularly towards exploring communication and stakeholder engagement. This paper identifies future themes and areas requiring investigation and application in this domain.  相似文献   

2.
黄骅港地区潮滩过程与港口选址   总被引:2,自引:0,他引:2  
对黄骅地区潮滩过程的基本特征进行了讨论,结果表明,该区潮滩发育主要受黄河泥沙的控制,黄河从本区或其附近入海期间是潮滩迅速淤涨期,当黄河远离本区时,潮滩便开始退缩进入调整期。目前本区潮滩过程的主要物质是潮滩本身的沉积物。漳卫新河的来沙是本区的主要物源。本潮滩的潮下带宽达9km以上,破波带外界在约4.0m水深处,港址选在泥沙活跃的破波带内是值得商榷的。建议港口建设应尽量避开破波带.  相似文献   

3.
Currents on either side of Well Bank were recorded for 41 days in May–June 1981, in order to distinguish locally tidally-generated asymmetries (pertinent to maintenance of the bank) from larger-scale and wind-driven flows.Semi-diurnal currents were dominant, nearly rectilinear and slightly inclined to the bank axis.Fourth-diurnal currents were consistent with previously observed and computed fourth-diurnal tides for the area overall; amplitudes varied as the square of the semi-diurnal amplitude. Hence they appear to be generated by tides, but only a small part locally.Residual currents (average over a tidal cycle) were always in the sense of clock-wise circulation around the bank, consistent with simple models and giving strong evidence of local generation by tides. This circulation combines with the semidiurnal currents to maintain the bank. The slow increase of the residuals with the semi-diurnal amplitude is interpreted as an effect of strong semi-diurnal currents. A persistent component onto the bank 7 m above the bottom at one position may indicate distortion of the frictional layer by the sloping bottom or by bank curvature.  相似文献   

4.
琼东南盆地北礁凹陷梅山组单向迁移水道特征及成因探讨   总被引:2,自引:1,他引:1  
李俞锋 《海洋学报》2019,41(1):72-86
深水区重力流与底流交互作用的过程、响应及动力学机制是海洋沉积学研究的前沿和薄弱环节。本文通过三维地震资料,在深水区北礁凹陷南西部梅山组发现多条相间分布的长条形顺直强振幅水道,垂直于西沙隆起(南部隆起)北斜坡走向,向南西方向单向迁移,水道具有南西陡(凹岸或陡岸)北东缓(凸岸或缓岸)的特征,该类水道分为侵蚀界面和水道砂-堤岸泥过渡复合体系两个单元,侵蚀界面在凹岸的削截反射明显多于凸岸,水道砂-堤岸泥过渡复合体振幅强度由凹岸强振幅逐渐过渡为凸岸弱振幅。分析认为,该类水道发育于中中新世半深海环境,不同于向底流下游方向单向迁移的峡谷,它们向底流上游方向发生单向迁移,并提出其成因模式:前期来自南部的浊流下切形成负向地貌单元(水道),底流对这一地貌单元进行改造,形成迎流面缓(凸岸)背流面陡(凹岸)的地貌,同时驱使浊流上部顺底流方向偏移,形成溢岸浊流沉积,致凹岸沉积速率低,凸岸沉积速率高,这样就迫使水道逆底流方向偏移。沉积物源、中层水相关底流、古气候和海平面的变化、北礁凸起古地形控制是该区单向迁移强振幅水道发育的因素。本研究在南海首次发现这种向底流上游方向单向迁移的水道,是底流与重力流交互作用的新型类型,对古海洋、古气候研究,深水油气勘探有着重要的意义,希望引起地质学家的重视。  相似文献   

5.
Fisheries managers face the dual challenge of achieving sustainable fisheries exploitation, while doing so through ‘light’ regulation. This is particularly the case in the European Union, where there is an overarching ‘better regulation’ agenda and new environmental management requirements under the Common Fisheries Policy. This paper explores the potential for using fisheries licensing schemes for environmental purposes in the EU, and so demonstrates their value as an instrument for environmental integration in the sector. The current and potential use of licence conditions and licensing within strategic management planning and assessments is explored in EU and non-EU fisheries, as well as other sectors. While not necessarily the solution to all environmental management challenges, licences are evidently a potentially valuable tool that can be used for more than mere entry limitation.  相似文献   

6.
This paper investigates to what extent limited entry licence local-link obligations hamper economic performance of Norwegian wet fish trawlers. For 1999 average landing prices, gross revenue, net profit and some other economic indicators are compared for three groups of trawlers: (A) vessels that had local-link licence obligations and complied with them; (B) vessels that had such obligations but did not comply; and (C) vessels without local-link obligations. Average operating profit was highest for Group C. Group B vessels’ operating profit was just above that of Group A, despite significantly higher revenues. For all fish species, except redfish, Group C trawlers received higher prices than the other vessels.  相似文献   

7.
珠江河口湾伶仃洋的地形   总被引:8,自引:7,他引:8  
赵焕庭 《海洋学报》1981,3(2):255-274
河口湾是河流终止于大陆前缘的半围圈的海域,河水和海水分别从河口湾的两端注入并混合为冲淡水。河口湾通常是由于冰后期海面上涨被海水淹没的河流下游部分。伶仃洋就是珠江的河口湾,为华南最大的河口湾。  相似文献   

8.
This work tests the robustness of policies and procedures designed to protect South Australia's marine environment through a case study of the Adelaide Desalination Plant—the most expensive (∼A$1.8 billion) infrastructure project in South Australia's history. Although this project has been subject to an Environmental Impact Assessment (EIA)—the highest level of assessment in Australia—on inspection it appears that the current operating licence for the desalination brine discharge breaches Government approval conditions and ignores the collective expert scientific advice of the project's Environmental Impact Statement (EIS). Hence, the EIA process in South Australia for this project is flawed. Improvements could be made to the South Australian system by including the requirements for operating licences as an integral part of the EIA.  相似文献   

9.
This paper examines the role of stewardship in offshore petroleum licensing systems, comparing Australia, Norway and the United Kingdom. These countries face similar challenges such as ageing infrastructure as production areas reach maturity, but have taken different approaches to evolving their ideas of stewardship to deal with them. One such approach is the UK's recently introduced strategy of maximising economic recovery of UK petroleum, which is indicative of a profound change to the traditional concession model on which its system is based. That model focuses on production in an individual licence area rather than achieving maximum value for the nation. This paper explores how this and other innovative approaches to stewardship can produce improved outcomes for the management of offshore petroleum and other natural resources, and in doing so suggests a way forward for countries like Australia who have relied on the concession model.  相似文献   

10.
Riverbank erosion is an important component of catchment sediment budget models but remains one of the least well-understood processes, particularly at large spatial scales. Here, we develop and test a new bank migration model in New Zealand for large catchment applications that (1) better represents spatial variability in factors influencing bank erosion and (2) improves predictive performance. We represent bank migration rates as a function of reach-scale stream power, channel sinuosity, soil texture, valley confinement, riparian woody vegetation and channel protection works. The new model significantly improves prediction compared to the SedNetNZ model. Comparison of measured bank migration rates with individual variables shows percent silt + clay derived from soil maps exhibited the strongest correlation, whereas other variables were non-significant. The model results demonstrate that improved prediction can be achieved by combining spatial representation of multiple factors over large areas, despite low correlation between individual variables and bank migration rates.  相似文献   

11.
Here we examine the consequences of strong tidal mixing on spatial and temporal distributions of biota and sea ice above Kashevarov Bank, Sea of Okhotsk, using data from field surveys (hydrography, pressure gauge and current meter moorings, and bio-acoustic soundings) and remote sensing (NOAA AVHRR). Fortnightly variations in the amplitude of diurnal tidal currents, primarily resulting from the K1–O1 interaction, are shown to dominate water motion over the bank. These currents (with maximum velocities 2 m s−1) create a sharp tidally-mixed front that separates well-mixed water above the bank from stratified water along its flanks. Such mixing draws water upward from the cold dichothermal layer (100–150 m) into the surface layer, and thus serves to ventilate the intermediate layers of the Sea of Okhotsk. In summer, fortnightly modulation of the tidal mixing creates temporal variations in water column stratification, a critical factor in the joint supply of nutrients and light required to sustain phytoplankton growth. As such, chlorophyll-a and oxygen values vary in response to the fortnightly cycle, and zooplankton likewise form dense aggregations within the tidally-mixed front in response to the phytoplankton production. It is further noted that the brood cycle of dominant zooplankton species on the bank matches the fortnightly modulation of the tidal currents. In winter, tidal mixing draws relatively warm water upward from mid-depth to maintain a polynya that cyclically opens and closes in response to fortnightly variation in vertical heat flux.  相似文献   

12.
以某港码头岸坡设计为例,利用极限平衡法和塑性极限分析法对边坡安全系数进行理论分析和对比研究,改进了港口地区岸坡稳定性的计算方法,并通过分析证明了十字板剪切强度指标在实际应用中的合理性。  相似文献   

13.
潮沟的边壁侵蚀可以分为水流作用下的边壁冲刷与土块重力作用下的边壁崩塌。前人研究表明,水流流速、水压及土体干密度等因素均对底床冲刷率有显著影响,然而侧向边壁的冲刷率量测以及相关影响因素问题亟待解决。前人较多关注侧向流对于边壁崩塌的影响,而对渗流作用以及渗流与侧向流在边壁侵蚀过程中的共同作用研究较少。近期研究表明,渗流已成为边壁侵蚀过程中的重要一环。因此,渗流与侧向流不同动力作用下,边壁侵蚀的差异性和相似性,以及两种动力共同作用下的侵蚀机制仍待进一步探究。  相似文献   

14.
Satellite-tracked drifters with drogues centered near-surface (5 m) and below the seasonal thermocline (50 m) were launched during late winter and spring of 1988 and 1989 in the northern Great South Channel in the western Gulf of Maine to investigate the regional circulation as part of the South Channel Ocean Productivity Experiment (SCOPEX). Many of the near-surface drifters became entrained in the clockwise gyre over Georges Bank, and eight drifters made a total of 16 complete circuits around the bank during the stratified season. The average recirculation period of these eight drifters was 48 days, and the average drifter speed around the bank was 12 cm s−1. There is no clear evidence from the drifter data that the strength of the clockwise gyre over the bank increased with time during the stratified season. On average, these drifters (i) followed a relatively narrow path around the bank, except over the eastern end of the bank where three preferred paths were observed, (ii) moved fastest over the northern and southern flanks of the bank, (iii) did not enter a core area of 3500 km2 centered at 41°17′N, 68°00′W, approximately 30 km southwest of the topographic center of the bank, and (iv) stopped circling the bank by the end of November, due in part to strong wind events that appeared to drive drifters off the bank. Curiously, none of the near-surface drifters moved from the southern flank of Georges Bank onto the New England shelf as might be expected from continuity of flow along the outer shelf; instead, the drifters that circled the bank tended to move off the bank along its southern flank. None of the drifters with drogues centered at 50 m appeared to recirculate around Georges Bank.  相似文献   

15.
We consider a model where the fluid depth depends on both horizontal coordinates, quasi-steady depth-uniform non-divergent fluid flow is governed by inertial, pressure and bottom-frictional forces, sand transport is proportional to the cube of the instantaneous current but augmented by a down-slope component and by wind-wave action, and sand is conserved.It is found that low parallel banks grow fastest, so that in an extensive spatially uniform sea previous calculations for linear banks are appropriate. The inclination of banks to the tidal currents can be interpreted in terms of similarly inclined deposition bands resulting from vorticity generation and advection in flow over a small isolated hump. A small bump can evolve to an equilibrium bank (typically after an initial rapid extension across the tidal currents) provided that sand is sufficiently restricted and particularly if some wind-wave action prevents growth up to the sea surface. Sand banks are likely to be in a late stage of evolution, when the main change is a slow lengthening as the net current and transport along the bank side slows and turns around the bank end with net deposition. The equilibrium is apparently stable except when there is an overall bed slope in the direction of the tidal currents, or when sand is abundant.  相似文献   

16.
Marine renewable energy is seen as an important component of the UK's future energy strategy and contribution to reducing the greenhouse gas emissions responsible for climate change. The UK aims to generate a total of 33 GW (gigawatts) of offshore wind energy. Its implementation strategy includes the development of ten offshore wind farms within Scottish territorial waters. In addition, between 1000 MW (megawatts) and 2600 MW of marine renewable energy generating capacity could be achieved in Scotland using wave and tidal power devices. However, there are negative environmental impacts associated with marine renewable energy. Intense noise is produced during pile driving, drilling and dredging operations with potential consequences for cetaceans. There are also increases in vessel activities during exploration, maintenance and construction with association risks of disturbance and collisions. Some underwater devices will be large and may be positioned in arrays across the habitats that cetaceans frequent. The consequences of encounters between cetaceans and such devices are as yet unknown. It is recommended that the Scottish Government complete full and transparent Marine Spatial Planning, including consideration of cumulative impacts, before moving to license appropriate sites.  相似文献   

17.
连云港至杭州湾北岸,海岸线长达千余公里;其海岸为一低地堆积平原岸,由于古黄河及长江的固体径流等的影响,曾经历了一个复杂的演变过程。海岸与河口面临开阔的浅海海域,经受着潮流强风浪与径流的作用,其岸滩与河口沙岛的动态具有独特之处。 对于苏北及长江口海岸的一些基本问题,不少学者先后从不同角度进行过研究,本文仅就海岸演变及其动态论述如下。  相似文献   

18.
-The groyne has been used widely in bank protection and river regulation.The plane layoutand structural style of groyne are closely related to the stability of the groyne itself and the effect of bankprotection.In this paper,based on the preliminary summary of the design of bank protection in the boresurging area of Qiantang River,some problems regarding the structure of groyne are pointed out and animproved plan is put forward.Site experiment was carried out combined with an emergency repair.The re-sults of the experiment indicate that the improved project is reliable and successful.  相似文献   

19.
Sand banks around straits are used as a commercial fishing ground. In order to clarify the mechanism of sand bank formation, the Lagrangian method was used to measure currents and turbidity around the banks in the Neko Seto Sea in the Seto Inland Sea of Japan. A neutrally buoyant float released in the Neko Seto Strait at the maximum tidal flow stage was engulfed in a pair of tidal vortices and moved around one of the sand banks. The vertical distribution of turbidity, which was measured by the vessel moving with the neutral float, showed an extremely high turbidity in the bottom layer of this bank area. According to the analysis of these observational data, the process of sand bank formation around straits is as follows. The tidal vortex transports water mass with suspended materials (including sand) which are whirled up at the bottom by the tidal jet. In the decaying stage of the vortex, the materials in the bottom layer are gathered in the central part of the vortex by the secondary convergent flow in the vortex. Among these materials, a large-size sand particle with a high critical erosion velocity accumulates at the bottom and forms banks. The distribution of bottom sediment and the thickness of alluvium support this result.  相似文献   

20.
淤泥质潮流深槽最大冲刷深度的一个概念模型   总被引:2,自引:1,他引:2  
以概念模式方法计算了淤泥质潮流深槽的最大深度,探讨了涨落潮流速、涨落潮历时、深槽淤泥质物质粒径、深槽顶底部原始深度、水道长度等因素对潮流深槽最大深度的影响。概念模式的假设条件是:(1)深槽形态为长方体,底部纵向坡度为0;(2)沉积物粒径无垂向变化;(3)只考虑潮流作用的影响,涨、落潮流速在时间序列上呈正弦分布;(4)不考虑细颗粒物质的粘性和絮凝作用。模拟结果显示:(1)涨、落潮历时对深槽最大深度的影响很小。(2)优势潮流流速与最大深槽深度之间存在着幂函数关系。(3)深槽的底质粒径、深槽的长度均与最大冲刷深度呈正相关关系。(4)深槽顶部水深与最大深度呈负相关关系。(5)由于潮汐水道深度与潮流流速和沉积物侵蚀强度之间具有负反馈关系,因此水道冲刷存在着一个极限,即最终可以达到均衡状态。潮流深槽的均衡态特征和达到均衡态所需的时间可运用沉积动力学方法来确定;同时,若应用深槽的真实参数,进一步减少模型的假设条件,可望使该模型具有实际的应用价值。  相似文献   

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