The objectives of this session were to examine the influenceof social behaviour and behavioural interactions (i) in understandingtemporal and spatial dynamics of fishes, and (ii) their effecton availability and catchability in resource and monitoringsurveys, fishing operations, and in the design of species-selectiveand ecosystem-friendly fishing gears. In her stimulating keynote address, Dr Julia Parrish challengedmany traditional approaches to the study of fish behaviour withinthe realm of fisheries biology. She reviewed the extensive theoryand literature covering the motivations, benefits, and costsof schooling and other group behaviour in fishes. She exploredbehavioural flexibility, that is, the ability to alter latencyto, or even type of, response that would allow individuals toinnovate behavioural pathways in the face of new situations.In exploited systems,  相似文献   

13.
Hydrodynamic and morphodynamic response of isolated and multiple low crested structures: Experiments and simulations     
《Coastal Engineering》2006,53(4):363-379
Low crested structures for beach defence purposes are frequently configured in the form of cells. This paper investigates the hydrodynamic and morphological response of such defence schemes by means of laboratory experiments and numerical simulations.Experiments were carried out at the large mobile-bed basin of the “Laboratorio di Idraulica Costiera” of the “Politecnico di Bari”, IT. Tests peculiarity is the simultaneous simulation of three different types of lateral confinement: a channel, representative of an indefinitely long structure, and two areas with narrow and wide gaps, representative of a common scheme and of an almost isolated structure respectively. Submerged, zero freeboard and emerged conditions were tested. A typical storm of the Northern Adriatic sea was reproduced by 6 wave attacks.Water level and currents were measured in front and behind the structures, at gaps and roundheads. Results, focusing on rip current intensities and piling-up, are presented and discussed. An extensive plan view of wave intensities and flow patterns inside the basin is provided through numerical simulations with MIKE 21 numerical suite.The sand bed was surveyed along 30 profiles covering the narrow gap area and the isolated structure roundheads. For the submerged conditions tests, 15 of these profiles and the shoreline position were monitored after each step of the simulated storm.Average and maximum values of local erosion at the structure toe are presented. Time evolution of erosion at gaps is related to the main hydrodynamic variables through Bijker sediment transport formula. Evaluation of volume changes in the protected area shows that sand is in average trapped behind the barriers, being transported offshore from gaps and returning inshore over the crest. The observed and reconstructed transport mechanism is a combination of bed load and suspended transport, the latter being slightly more important.Bed level changes are well predicted by morphodynamic simulations performed with MIKE 21 CAMS.  相似文献   

14.
Adsorption and desorption of proteins and polyamino acids by clay minerals and marine sediments   总被引:1,自引:0,他引:1  
Xiaoling Ding  Susan M. Henrichs 《Marine Chemistry》2002,77(4)
The adsorption and desorption of proteins and polyamino acids on illite, montmorillonite, goethite, and marine sediments was investigated. Three 14C-labeled hydrophilic proteins, Rubisco from C. reinhardtii, and GroEL and GroES from genetically modified Escherichia coli, were synthesized and purified for this study. The proteins were strongly and rapidly adsorbed by the clay minerals and marine sediments, and much of the adsorbed protein was not readily desorbed. Sodium dodecyl sulfate (SDS) extraction and separation by SDS-polyacrylamide gel electrophoresis (PAGE) and sucrose density gradients showed that Rubisco and GroEL were adsorbed on illite and sediments in their original forms. The apparent adsorption partition coefficients of the proteins were on the order of 102 l/kg on illite, 103–104 l/kg on goethite and montmorillonite, and 200 and 75 l/kg on Skan Bay and Resurrection Bay (Alaska) sediments, respectively. These partition coefficients are sufficiently large to permit sedimentary protein preservation via an adsorptive mechanism. Generally, basic polyamino acids had greater adsorption partition coefficients than acidic polyamino acids. Molecular size did not affect the electrostatic interaction between polyamino acids and mineral surfaces. Adsorption of bovine serum albumin (BSA) and negatively charged polyamino acids inhibited Rubisco adsorption, while positively charged cytochrome c and polyamino acids increased Rubisco adsorption. These results indicate that electrostatic interactions dominated in protein adsorption.  相似文献   

15.
渤海冬夏季营养盐和叶绿素a的分布特征   总被引:18,自引:0,他引:18  
赵蓦  田纪伟  赵仕兰  吴自库 《海洋科学》2004,28(4):34-39
在2000年8月和2001年1月对渤海进行的两个航次的调查取样的基础上,分析渤海营养盐和叶绿素a的分布特征,各海区营养盐的结构以及营养盐和叶绿素a的关系。结果表明,冬季营养盐的浓度高于夏季,硅酸盐有明显的垂向结构,40多年来渤海中部硝酸盐呈现增加趋势;莱州湾浮游植物生长处于磷限制,其它海区处于氮限制;冬季叶绿素a的浓度也高于夏季,叶绿素a的季节差异可能与夏季浮游动物对浮游植物的大量摄食有关。  相似文献   

16.
Ocean-dumping research and monitoring: Strategies and tools     
Simpson  D. Devine  M. Warsh  C. Meyer  E. O'Connor  T. P. Park 《Oceanic Engineering, IEEE Journal of》1978,3(4):165-171
Ocean-dumping studies are designed to establish critical indexes of environmental quality to assess the impacts of ocean dumping. Strategies emphasized are: 1) source function characterization including determinations of toxicities of original wastes, 2) environmental characterization, 3) waste dispersion studies in the laboratory and at sea, and 4) waste biota interaction studies, both in the short term, within a life cycle of organisms affected, and in the long term, over many life cycles. Present tools include: 1) quantitative mapping of pollutant distribution by aerial remote sensing and moored and drifting arrays, 2) realtime tracking of waste dispersion in the ocean by 20- and 200-kHz acoustic records, 3) continuous multidepth water sampling to obtain sea truth, 4) in situ bioassay devices, and 5) mathematical dispersion models, some of which are similar to atmospheric chimney plume dispersion models.  相似文献   

17.
冲绳海槽96、155号岩心放射虫与年代地层及古气候特征   总被引:8,自引:1,他引:7  
程振波  王永吉  鞠小华 《海洋学报》1998,20(1):74-80
本文根据对冲绳海槽96、155号岩心中的放射虫化石分析,结合有孔虫、孢粉、植物硅酸体等综合研究资料及AMS14C测年、磁性地层学的测试结果,粗略地探讨了冲绳海槽晚第四纪以来的古海洋学特点及东海大陆架古气候变化的规律.  相似文献   

18.
饵料生物生产与自然耕种及生活污水、农业废物的处理     
朱祖培 《台湾海峡》1998,(Z1)
高畦深沟种植水稻、有机蔬菜,沟中施投化粪池污水、生活废水、腐烂瓜果蔬菜、各类粪便、田间杂草、藤蔓秸秆等培养水蚯蚓、福寿螺、小球藻、水蚤等饵料生物,构成良性循环的人工生态系统,通过水生生物和农作物的作用使有机污染物在田间得到衰减和清除。这种立体生产、综合利用集约生产模式,有利于降低饵料生物生产成本,有助于解决自然耕种收获量较少、成本较高的问题,能使有机垃圾、污水处理工艺简单、费用少,并能变废为宝生产出大量的动物蛋白和植物蛋白。  相似文献   

19.
Estimates of phytoplankton and bacterial biomass and production in the northern and southern Benguela ecosystems     
《African Journal of Marine Science》2013,35(1):537-564
Available data on phytoplankton and bacterial abundance and production off the coasts of southern Africa (to the 500 m depth contour) have been assembled and analysed for a network analysis of carbon flow in the Benguela ecosystem. Phytoplankton carbon biomass (from measurements of chlorophyll a) in the northern Benguela (2 558 300 tons) was considerably higher than in the southern Benguela (671 420 and 516 400 tons for the West and South coasts respectively). However, overall annual production (from C14-uptake measurements) was similar, 77 416 608, 76 399 973 and 78 988 020 tons C·year?1 respectively. Phytoplankton respiration and sedimentation losses were calculated as functions of primary production and therefore followed similar trends. From the most conservative estimates (mean bacterial biomass of 10 mg C·m?3 and average P:B of 0,2·day?1) bacterial biomass is 2–7 per cent of phytoplankton biomass in the northern and southern Benguela, and bacterial production is 3–5 per cent of primary production. Assuming a net growth yield of 30 per cent, bacteria would need to consume 9–15 per cent of the total primary production in order to meet their requirements for carbon consumption. Calculations based on a mean bacterial biomass of 40 mg C·m?3 and a mean growth rate of 0,5·day?1 in the upper 30 m of the water column show bacterial biomass to be 8–27 per cent of phytoplankton biomass and bacterial production to be 26–44 per cent of phytoplankton production. Bacterial carbon consumption requirements at these rates amount to 86–147 per cent of total primary production.  相似文献   

20.
秦皇岛河流-海岸水动力和水质耦合模拟分析     
顾杰  胡成飞  李正尧  匡翠萍  张永丰 《海洋科学》2017,41(2):1-11
基于MIKE FLOOD建立秦皇岛入海河流及其近岸海域一维、二维耦合河流-海岸水动力和水质模型,研究了秦皇岛海域和入海河流的水动力和污染物分布规律。结果表明:(1)海域潮流为半日潮,其中石河口南北支入海口流速变化过程差别较大,但水位变化过程基本一致;(2)整体上河流入海口化学需氧量(COD)与流速呈正相关关系;(3)COD在近岸海域的扩散方向与涨落潮潮流方向一致,各入海河口海域落潮流期间的COD高于涨潮流。如上结论为赤潮爆发机理和应急处置研究提供科学依据和技术支持。  相似文献   

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1.
The urgency and specific features of the application of the up-to-date aerospace methods and technologies in order to monitor different oil and gas facilities; study subsurface geology of oil and gas areas; search for oil and gas deposits (particularly in Arctic regions); control oil, gas, and product pipelines; and estimate the environmental conditions in the areas of hydrocarbon production and transportation on land and on the sea are justified and analyzed. The problems in the oil and gas industry which can be solved using aerospace data are systematized. The principles of organization of aerospace monitoring and the physical bases of remote sensing methods for solving different problems in the oil and gas industry are considered. The application of aerospace methods and technologies in order to monitor the environmental conditions in the oil and gas production areas, monitor pipelines, detect pollution of the marine environment with oil products (particularly, after the accident on the oil platform in the Gulf of Mexico in 2010), and control the ice conditions in the Arctic oil and gas areas is illustrated.  相似文献   

2.
The east and northeast Brazil shelves of the Southwest Atlantic harbor some unique conditions for tropical passive margins with western boundary currents. The narrow and open shelf is almost entirely covered by carbonate sediments due to little freshwater input and the coast is impacted by the South Equatorial Current (SEC). The wide Abrolhos bank of the east Brazil shelf, presents more diverse conditions, as it forms a physical barrier to the Brazil Current, and upwelling and land input become more significant. The main characteristics of the coast and shelf and findings on biogeochemical, sedimentation, and paleoceanographical processes, addressed by the Joint Oceanographic Projects (JOPS) campaigns, are summarized.  相似文献   

3.
分析了海洋测绘教育培训国际化和标准化的原因及进程,论述了海洋测绘国际化教育培训的指导性文件及内容,针对国际化海洋测绘教育培训的特点与发展趋势,提出了发展我国海洋测绘教育培训的对策与建议。  相似文献   

4.
聚多巴胺(polydopamine, PDA)含有大量的酚羟基和氨基官能团, 可以在玻璃、不锈钢、塑料、橡胶、聚四氟乙烯等材料表面黏附, 具有优异的粘附性能, 是重要的功能材料之一。本文对近年来国内外围绕聚多巴胺展开的研究进行了综述, 从聚多巴胺的合成方法、聚合机理和性能出发, 分析总结了当前合成的特点、机理研究的方案和存在的问题, 并对聚多巴胺在海洋防腐领域的应用进行了总结和展望, 旨在为研究者较全面了解聚多巴胺的研究现状提供参考。  相似文献   

5.
The paper describes the functional scheme of the soft- and hardware complex designed to receive, to treat and to disseminate satellite and reference hydrometeorological data. The complex displays a high degree of integration and unification of soft- and hardware techniques and packages. The operation of the complex is studied through the monitoring of cloud fields in the Atlantic-European section of the Northern hemisphere during the winter-time synoptic season of 1995–1996. The complex is shown to be capable of identifying large-scale cloud anomalies and of estimating their coherence in the individual regions of the Atlantic-European zone. Translated by Vladimir A. Puchkin.  相似文献   

6.
《Marine Policy》2005,29(2):175-183
Specific voluntary guidelines are proposed for military and intelligence gathering activities in the EEZ. Views on the guidelines range from strong reservations regarding any restrictions on these activities to support for some restrictions. There is general support for the effort to promote mutual understanding and agreement on the rights and obligations of the maritime powers which do not want any rules and coastal States that want some predictability and protection against intimidation. The challenge is to find a practical way of handling these issues. Suggestions are provided regarding requisite specific assurances and the process for implementing and enforcing any such guidelines. State consent and State practice will play a significant role in this process.  相似文献   

7.
探讨了壳寡糖及全乙酰壳寡糖的制备方法,通过正交实验考察了原料、温度、时间对降解产物的影响.制备了八种寡糖(八乙酰壳二糖、十一乙酰壳三糖、十四乙酰壳四糖和十七乙酰壳五糖,以及N,N′-二乙酰壳二糖、N,N′,N″-三乙酰壳三糖、N,N′,N″,N′′′四乙酰壳四糖和N,N′,N″,N′′′,N′′′′-五乙酰壳五糖),并通过IR、NMR及MS等确定了其化学结构.  相似文献   

8.
The Eastern and Southeastern Asian regions witness the strongest land–ocean and lithosphere–asthenosphere interactions. The extreme diversity of geological features warrants a unified study for a better understanding of their geodynamic uniqueness and/or ubiquity from a regional perspective. In this paper we have explored a large coverage of potential field data and have detected high resolution Moho and Curie depths in the aforementioned regions. The oldest continental and oceanic domains, i.e. the North China craton and the Pacific and Indian Ocean have been found thermally perturbed by events probably linked to small-scale convection or serpentinization in the mantle and to numerous volcanic seamounts and ridges. The thermal perturbation has also been observed in proximity of the fossil ridge of the western Philippine Sea Basin, which shows anomalously small Curie depths. The western Pacific marginal seas have the lowest Moho temperature, with Curie depths generally larger than Moho depths. The contrary is true in most parts of easternmost Eurasian continent. Magmatic processes feeding the Permian Emeishan large igneous province could have also been genetically linked to deep mantle/crustal processes beneath the Sichuan Basin. The regionally elongated magnetic features and small Curie depths along the Triassic Yangtze-Indochina plate boundary suggest that the igneous province could be caused by tectonic processes along plate margins, rather than by a deep mantle plume. At the same time, we interpret the Caroline Ridge, the boundary between the Pacific and the Caroline Sea, as a structure having a continental origin, rather than as hotspot or arc volcanism. The surface heat flow is primarily modulated by a deep isotherm through thermal conduction. This concordance is emphasized along many subduction trenches, where zones of large Curie depths often correspond with low heat flow. Local or regional surface heat flow variations cannot be faithfully used in inferring deep thermal structures, which can be better constrained overall through Curie depths detected from surface magnetic anomalies.  相似文献   

9.
Phthalate esters and γ-hexachlorocyclohexane are among the organic xenobiotics which are most abundant in the atmospheric fallout over Bermuda. It was therefore of interest to study the uptake and elimination of these synthetic components in the most important reef building coral. Diploria strigosa and the mussel Arca zebra, from Bermudian waters. Radioactive labelled components (14C-γ-hexachlorocyclohexane, diisononyl [carboxyl-14C] phthalate) were used in the study and the samples were analyzed by liquid scintillation counting.The highest concentrations of radioactivity were found in hepatopancreas and more phthalate ester than lindane was taken up. In gill, muscle and coral tissues the uptake of lindane was higher than that of the phthalate ester. In all tissues analyzed the elimination rate of lindane was higher than that of the phthalate ester.The acute effects of phthalate esters on corals are probably less than those of lindane, due to the low uptake and low toxicity. However, the poor elimination of phthalate esters may lead to long-term effects.  相似文献   

10.
Current meter data collected over the last 20 years are presented and used to describe the residual currents on the Celtic and Armorican slope and shelf regions. On the slopes, a poleward current of about 6cm s−1 exists at the 500m depth contour. At mid depths, these currents are directed onslope, whereas near the bottom the flow in markedly downslope, reaching mean speeds of about 15cm s−1 near 6°40′W. The downslope currents are thought to be largely tidally induced and balanced by Stokes transports. The total slope transport near 48°N is about 4Sv. On the upper slopes (<1000m depth) the transport increases poleward. On the outer Celtic shelf, a weak (2 cm s−1) counter-current flowing southeastwards was observed. On the Armorican shelf, the residual flow is again nothwestwards and this coastal flow appears to continue northwards across the mouth of the English Chanel and past the Isles of Scilly with typical mean upper layer speeds of about 2cm s−1. Southwest of Ireland the flow is again northwesterly. Numerical model simulations show that the eastern slope boundary current of the NE Atlantic can be driven by realistic distributions of seawater density. The simulations also show only a small wind driven barotropic response on the Celtic and Armorican shelf region and that a component of the residual shelf flows, like the slope current, may be driven by pressure distributions arising from regional differences in the distribution of seawater density, or from non local wind stress.  相似文献   

11.
The airborne laser scanning LIDAR (LIght Detection And Ranging) provides high-resolution Digital Terrain Models (DTM) that have been applied recently to the characterization, quantification and monitoring of coastal environments. This study assesses the contribution of LIDAR altimetry and intensity data, topographically-derived features (slope and aspect), and multi-spectral imagery (three visible and a near-infrared band), to map coastal habitats in the Bidasoa estuary and its adjacent coastal area (Basque Country, northern Spain). The performance of high-resolution data sources was individually and jointly tested, with the maximum likelihood algorithm classifier in a rocky shore and a wetland zone; thus, including some of the most extended Cantabrian Sea littoral habitats, within the Bay of Biscay. The results show that reliability of coastal habitat classification was more enhanced with LIDAR-based DTM, compared with the other data sources: slope, aspect, intensity or near-infrared band. The addition of the DTM, to the three visible bands, produced gains of between 10% and 27% in the agreement measures, between the mapped and validation data (i.e. mean producer's and user's accuracy) for the two test sites. Raw LIDAR intensity images are only of limited value here, since they appeared heterogeneous and speckled. However, the enhanced Lee smoothing filter, applied to the LIDAR intensity, improved the overall accuracy measurements of the habitat classification, especially in the wetland zone; here, there were gains up to 7.9% in mean producer's and 11.6% in mean user's accuracy. This suggests that LIDAR can be useful for habitat mapping, when few data sources are available. The synergy between the LIDAR data, with multi-spectral bands, produced high accurate classifications (mean producer's accuracy: 92% for the 16 rocky habitats and 88% for the 11 wetland habitats). Fusion of the data enabled discrimination of intertidal communities, such as Corallina elongata, barnacles (Chthamalus spp.), and stands of Spartina alterniflora and Phragmites australis, which presented misclassification when conventional visible bands were used alone. All of these results were corroborated by the kappa coefficient of agreement. The high classification accuracy found here, selecting data sources, highlights the value of integrating LIDAR data with multi-spectral imagery for habitat mapping in the intertidal complex fringe.  相似文献   

12.
   Discussion summary: session 3
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