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1.
A new tool was developed for large volume sampling to facilitate marine microbiology and biogeochemical studies. It was developed for remotely operated vehicle and hydrocast deployments, and allows for rapid collection of multiple sample types from the water column and dynamic, variable environments such as rising hydrothermal plumes. It was used successfully during a cruise to the hydrothermal vent systems of the Mid-Cayman Rise. The Suspended Particulate Rosette V2 large volume multi-sampling system allows for the collection of 14 sample sets per deployment. Each sample set can include filtered material, whole (unfiltered) water, and filtrate. Suspended particulate can be collected on filters up to 142 mm in diameter and pore sizes down to 0.2 μm. Filtration is typically at flowrates of 2 L min−1. For particulate material, filtered volume is constrained only by sampling time and filter capacity, with all sample volumes recorded by digital flowmeter. The suspended particulate filter holders can be filled with preservative and sealed immediately after sample collection. Up to 2 L of whole water, filtrate, or a combination of the two, can be collected as part of each sample set. The system is constructed of plastics with titanium fasteners and nickel alloy spring loaded seals. There are no ferrous alloys in the sampling system. Individual sample lines are prefilled with filtered, deionized water prior to deployment and remain sealed unless a sample is actively being collected. This system is intended to facilitate studies concerning the relationship between marine microbiology and ocean biogeochemistry.  相似文献   

2.
Sediment traps are an important tool for studying the source, composition and sedimentation processes of sinking particulate matter in the ocean. An in situ observational mooring(TJ-A-1) is located in the northern South China Sea(20.05°N, 117.42°E) at a water depth of 2 100 m and equipped with two sediment traps deployed at 500 m and 1 950 m. Samples were collected at 18-day intervals, and 20 samples were obtained at both depths from May 2014 to May 2015. Large amounts of fecal matter and marine snow were collected in the lower trap. The fluxes of marine snow and fecal pellets exhibited a fluctuating decrease between May 2014 and early August 2014 and then stabilized at a relatively low level. Scanning electron microscopy observations revealed that the main components of the marine snow and fecal pellets were diatoms, coccolithophores, radiolarians, and other debris, all of which are planktons mostly produced in photic zone. Used in conjunction with the particle collection range estimates from the lower trap and data on ocean surface chlorophyll, these marine snow and fecal pellets were related to the lateral transport of deep water and not vertical migrations from overlying water column. Moreover, the source area might be southwest of Taiwan.  相似文献   

3.
This article summarizes the author's work on210Pb and210Po distributions in the marine environment for which the Okada Prize of the Oceanographical Society of Japan was awarded. In this review, the work of other investigators and the studies now going on are also included. The210Pb concentration in the surface water of the ocean is controlled by the atmospheric flux of210Pb and productivity. The disequilibrium between226Ra and210Pb in the deep sea reveals that the oceanic residence time of lead is less than a hundred years rather than of the order of thousands of years as thought before based on stable lead measurement in ocean water. Particulate removal of210Pb from the water column is likely to be the major cause of the deficiency of210Pb in the water, however more investigations would be needed to clarify the detailed removal mechanism of210Pb. The experiments on particulate flux by using sediment traps will provide an unique opportunity to examine this. 210Pb in excess of226Ra in sediment is useful for geochronology of shallow water sediments and the study on bioturbation rates on the deep sea sediments.  相似文献   

4.
针对深渊生物资源研究的需求,自主研发了用于全海深深度的深渊沉积物、水体和宏生物的保压取样装置,深渊沉积物保压转移装置,深渊微生物原位过滤及保存装置和高压培养高压酶学测定装置。在深海模拟环境验证了取样装置在万米深度下的工作性能。相关装置在“探索一号”科考船的TS15、TS21-1和TS21-2大洋科考航次中,搭载“奋斗者”号载人潜器、“2号”深渊着陆器、“原位实验”号着陆器于西菲律宾盆区和马里亚纳海沟进行了海上试验,成功获取了万米深度沉积物、水体和宏生物保压样品以及微生物原位过滤滤膜;成功进行了沉积物保压样品的保压转移试验。初步形成了深渊海域生物资源取样的装备技术体系,为深渊海底生物和基因资源开发,深渊生命过程等科学研究提供技术手段。  相似文献   

5.
The results of an intercomparison of three types of sampling device and three types of hydrowire, used for the collection of seawater samples for trace metal analysis, are presented. These devices were intercompared in an international experiment involving member states of the Intergovernmental Oceanographic Commission through the collection of mid-depth North Atlantic water samples at Panulirus Station near Bermuda. Of the commercially available sampling devices, modified GO-FLO samplers appear to yield the lowest concentration seawater samples with modified Niskin samplers having only slightly inferior capability. Both unmodified GO-FLO and Hydro-Bios samplers have similar, but generally poorer, abilities for the collection of uncontaminated samples. Of the three hydrowires intercompared, plastic-coated steel yields the lowest concentration samples for most metals. Kevlar and stainless-steel hydrowires appear to cause only slight contamination for some metals. Overall, the impression is obtained that differences between the levels of metals in the ocean reported by different laboratories is predominantly due to analytical, rather than sampling errors or artifacts.  相似文献   

6.
A pair of buoys (system), MET and OPTICAL, consisting of fully automated hyperspectral radiometers, fluorometer, and meteorological sensors, has been realized and deployed in deep ocean case-I site at Kavaratti in Lakshadweep, Arabian Sea, for preprogrammed in situ data collection and transmission via INSAT-3C satellite. The buoy of described configuration is capable of measuring in-water optical and biological parameters in an unattended manner for long-term time series with less vertical tilt. A robotic sun/sky photometer installed on Kavaratti Island simultaneously provides information on aerosols over the site. A combination of these parameters available hourly in real time throughout the day from unattended systems in the ocean as well as on island provides an ideal reference site. The paper reports recent collection of bio-optical marine observations over the site and use of the data for OCM-2 vicarious calibration and validation of geophysical products.  相似文献   

7.
Society’s needs for a network of in situ ocean observing systems cross many areas of earth and marine science. Here we review the science themes that benefit from data supplied from ocean observatories. Understanding from existing studies is fragmented to the extent that it lacks the coherent long-term monitoring needed to address questions at the scales essential to understand climate change and improve geo-hazard early warning. Data sets from the deep sea are particularly rare with long-term data available from only a few locations worldwide. These science areas have impacts on societal health and well-being and our awareness of ocean function in a shifting climate.Substantial efforts are underway to realise a network of open-ocean observatories around European Seas that will operate over multiple decades. Some systems are already collecting high-resolution data from surface, water column, seafloor, and sub-seafloor sensors linked to shore by satellite or cable connection in real or near-real time, along with samples and other data collected in a delayed mode. We expect that such observatories will contribute to answering major ocean science questions including: How can monitoring of factors such as seismic activity, pore fluid chemistry and pressure, and gas hydrate stability improve seismic, slope failure, and tsunami warning? What aspects of physical oceanography, biogeochemical cycling, and ecosystems will be most sensitive to climatic and anthropogenic change? What are natural versus anthropogenic changes? Most fundamentally, how are marine processes that occur at differing scales related?The development of ocean observatories provides a substantial opportunity for ocean science to evolve in Europe. Here we also describe some basic attributes of network design. Observatory networks provide the means to coordinate and integrate the collection of standardised data capable of bridging measurement scales across a dispersed area in European Seas adding needed certainty to estimates of future oceanic conditions. Observatory data can be analysed along with other data such as those from satellites, drifting floats, autonomous underwater vehicles, model analysis, and the known distribution and abundances of marine fauna in order to address some of the questions posed above. Standardised methods for information management are also becoming established to ensure better accessibility and traceability of these data sets and ultimately to increase their use for societal benefit. The connection of ocean observatory effort into larger frameworks including the Global Earth Observation System of Systems (GEOSS) and the Global Monitoring of Environment and Security (GMES) is integral to its success. It is in a greater integrated framework that the full potential of the component systems will be realised.  相似文献   

8.
Results of organic carbon, total nitrogen, amino acid and hexosamine analyses of samples collected during time-series sediment trap investigations in the Arabian Sea are presented. Samples were taken over a period of years at two depths at each of three locations in the western, central and eastern part of the basin. Seasonal changes in amino acid contents and their spectral distributions show that degradation of organic matter in the water column is reduced during the monsoons, which are the high-flux periods in the western and central Arabian Sea. At the eastern site more degraded material of possibly recycled marine or terrestrial origin reaches the traps during the late summer peak fluxes. The results of hexosamine analyses suggest that bacterial biomass is relatively enriched on particles sinking in the water column and, to a larger extent, at the sediment-water interface. Decomposition between intermediate and deep water results in a loss of 30–40% of total organic carbon and more than 40% of amino acids. Comparison of the measured accumulation rates of organic carbon in sediment traps with those of organic carbon preserved in sediments show that more than 85% is lost before final burial in the sediments. Organic matter preservation in the Arabian Sea is higher than the average for the open ocean; this maybe due to the abundance of refractory organic matter of recycled marine or terrestrial origin.  相似文献   

9.
Scientific sea-floor dredging is currently used in marine geology primarily by the hard-rock community interested in the recovery of basement rock samples from the unsedimented deep ocean floor. The technique has generally been eclipsed by ocean drilling for recovery of sedimentary rocks, because of perceived uncertainties in the location of sampling and in the representativeness of recovered material. This contribution reviews dredging equipment currently in use by marine geological institutions and refers to pinger attachments that allow precise information on the behaviour of the dredge to be telemetered back to the ship. We argue that improvements in ship navigation and transponder navigation at the seafloor, when used in conjunction with surface and/or deeply towed sidescan and swathemapping surveys, now allow for considerably less uncertainty on the location of dredge sampling. Refined sorting criteria for dredge hauls are now also available. Recent comparisons of regional sample recovery by ocean drilling and by dredge sampling indicate that the dredge hauls can usefully supplement the drilling data in the construction of sedimentary and tectonic histories of seafloor areas.  相似文献   

10.
In this article, sampling locations, sample types, sample processing methods, and certified values of ocean manganese nodule and sediment reference materials available throughout the world are briefly described. Recommended or information values of major, minor, and trace constituents in those samples have also been collected, and a review of the main characteristics of their property values is presented.  相似文献   

11.
An investigation of biological transport processes which may link the deep ocean floor to shallow depths was carried out at a site on the Madeira Abyssal Plain, depth 5440m, position 31°17′N 25°24′W. Benthic and midwater sampling was carried out concurrently; time lapse photography provided an estimate of biological activity on the bottom.Biomass was measured throughout the water column; overall biomass was low and no evidence was found for mass upward transport resulting from biological activity. The potential for transport via individual species does exist since a number of species were distributed from the sea bed to thousands of metres above the bottom. However, theres is no direct evidence for vertical migrations through these vast depth ranges and the numbers of individuals concerned is very small. The arrival and possible predation of a large food parcel on the deep sea floor was observed.  相似文献   

12.
Studies on the biogeochemical cycling of organic contaminants in the Mediterranean have demonstrated the importance of polychlorinated biphenyls (PCBs) as relatively stable markers of recent anthropogenic influence in ocean systems. This paper presents results of hydrocarbon analyses of deep water profiles, sediments and their associated surface flocculent layers, and zooplankton samples collected in the western basin. Seawater concentrations were higher than those previously reported for the eastern basin and were consistent with the presence of industrial sources in the northwestern segment. In the water column, the percent of PCBs associated with filterable particles was related to the ambient concentrations of total suspended matter, distance from coastal input sources and on depth. The occurrence of deep water residues primarily in the dissolved phase and observations of subsurface maxima in seawater concentrations during a season of high surface productivity were consistent with the predictions of vertical transport models based on residues associated with sinking particles and equilibrium partitioning. Flocculent layers at the sea/sediment interface contained two and three orders of magnitude, respectively, more PCBs and petroleum hydrocarbons (PHCs) than their associated surface sediments. The flocculent particles also contained several biogenic hydrocarbons presumably originating from plankton and relatively soluble and labile contaminants such as hexachlorohexane isomers (HCH) and hexachlorobenzene (HCB), thus confirming that the majority of the flux of hydrocarbons to sediments is carried on rapidly settling large particles. By combining the sediment and flocculents data with published sedimentation rates for the deep basins of the Mediterranean, a yearly flux rate of PCBs to the open sea sediments was estimated as 13 μg m−2 yr−1 or less than half of the rate measured in a coastal sediment trap experiment. Analytical results are placed in the context of other distribution data for PCBs and long-term flux studies to construct a partial mass balance budget for this semi-enclosed sea. The computed coastal inventory showed that about 35% remains suspended in the water column while the majority of residues are deposited in coastal sediments. However in the open sea, the deep water column may contain up to 70% of the total inventory and may be a continually increasing reservoir of stable organic contaminants reaching the ocean. The budget shows that priority for improved research and monitoring efforts in ocean systems should be given to continued advancement in techniques for the precise measurement of deep water concentrations and for measuring current atmospheric inputs and sedimentation rates in order to develop more accurate ocean flux models.  相似文献   

13.
Ocean policies around the world increasingly emphasize the importance of maintaining resilient ocean ecosystems, communities, and economies. To maintain and restore the resilience of healthy marine ecosystems in practice, specific management objectives with metrics and a policy framework for how to apply them will be needed. Here we present a concept for doing this, based on evidence that marine ecosystems transition from desirable to less desirable states in response to a number of physical, chemical, and biological drivers. More empirical and synthesis research will be necessary to develop quantitative metrics of resilience and thresholds between ecosystem states for specific ecosystems; however, suggestions are provided here for how to manage for resilience when insufficient data and knowledge are available for quantification. A summary of thresholds for biotic and abiotic drivers of ecosystem state drawn from the literature is also provided as a guide to management.  相似文献   

14.
痕量元素及其同位素采集、预处理和分析在海洋研究中具有重要的作用,对于认识全球环境变迁具有重要的价值。但其浓度在这些过程中易受沾污。本文结合海水痕量元素CTD现场采集工作环境,工作拉力等特殊要求,先后跟缆绳设计、生产制造厂家进行缆绳相关技术讨论、确定缆绳各项技术指标。设计敷塑纤维通讯缆,并委托缆绳生产厂家加工出样缆两条。通过对样缆进行静态拉力试验验证缆绳自身工作拉力,并通过成分分析、浸出试验验证最大化减少缆绳对于海中溶解态痕量金属的沾污。该研究结果可提高采样过程的可靠性,保证数据的准确率。  相似文献   

15.
Ultrastructure dissolution susceptibility of the planktic foraminifer Globigerina bulloides, carbonate ion content of the water column, calcium carbonate content of the sediment surface, and carbonate/carbon weight percentage ratio derived from sediment surface samples were investigated in order to reconstruct the position of the calcite saturation horizon, the sedimentary calcite lysocline, and the calcium carbonate compensation depth (CCD) in the modern South Atlantic Ocean. Carbonate ion data from the water column refer to the GEOSECS locations 48, 103, and 109 and calcium carbonate data come from 19 GeoB sediment surface samples of 4 transects into the Brazil, the Guinea, and the Cape Basins. We present a new (paleo-) oceanographic tool, namely the Globigerina bulloides dissolution index (BDX). Further, we give evidence (a) for progressive G. bulloides ultrastructural breakdown with increasing carbonate dissolution even above the lysocline; (b) for a sharp BDX increase at the sedimentary lysocline; and (c) for the total absence of this species at the CCD. BDX puts us in the position to distinguish the upper open ocean and the upwelling influenced continental margin above from the deep ocean below the sedimentary lysocline. Carbonate ion data from water column samples, calcite weight percentage data from surface sediment samples, and carbonate/carbon weight percentage ratio appear to be good proxies to confirm BDX. As shown by BDX both the calcite saturation horizon (in the water column) and the sedimentary lysocline (at the sediment–water interface) mark the boundary between the carbonate ion undersaturated and highly corrosive Antarctic Bottom Water and the carbonate ion saturated North Atlantic Deep Water (NADW) of the modern South Atlantic.  相似文献   

16.
I am extremely grateful and honored for being awarded the Okada Prize (1985) for my study. The present article reviews my research on the distribution, behavior and fate of PCBs in the marine environment. The outline of this study is summarized as follows:
  1. Polychlorinated biphenyls (PCBs) were detectable in the wide range of environmental media and biota of the Seto-Inland Sea, Japan, in which much high concentrations were found in sediment and biological samples due to their hydrophobic, lipophilic and less biodegradable properties as well as their extensive production and use in estuarine and coastal regions.
  2. PCBs extend the boundaries of their distribution all over the global environment, being evidenced by their occurrence in open ocean atmosphere, hydrosphere and biosphere, even in Antarctica. The global contamination of PCBs is much more prominent in northern hemisphere than in southern hemisphere.
  3. The sinking rate of PCBs from surface to deeper layers in open ocean water column is relatively slower in tropical waters than in high latitude ones. This implies the possible prolonged contamination of persistent synthetic organic chemicals in the tropical marine environment.
  4. The bioaccumulation processes in marine ecosystems can be explained by the physicochemical and biochemical properties of PCBs and the metabolic capacity of organisms. In higher animals, additional factors such as parturition and lactation are also related to this process.
  5. Total PCB load in global environment was estimated to be about 370 thousand tons. Of this, most amounts were in coastal sediment and open ocean water. Presently, about 780 thousand tons of PCBs are still in use mainly in electrical equipments. In order to reduce the PCB levels in marine environment, pertinent measures to prevent the further discharge and safe disposal of PCBs are required.
  相似文献   

17.
The detailed investigation of organic carbon cycling in estuarine and marine environments has stimulated the development of multidisciplinary concepts, research and sampling strategies as well as analytical tools in the last 10 years. Among other approaches, the molecular biomarker one has also undergone significant improvements. Some examples dealing with specific markers including sterols, alkenes and fatty acids are discussed in this paper in terms of source identification and transformation processes.Although some limitations exist for the elucidation of their stereochemistry, sterols have been used extensively to study biochemical processes affecting the organic matter in the water column and at the ocean/sediment interface. Sterols also appear as promising tracers of terrestrial vs. marine inputs in complex estuarine systems. The specificity of individual fatty acids or groups of acids has also been used to assess the origins and transformation processes of organic matter in marine samples. New approaches are presented including the investigation of intact lipid classes and the elucidation of the position of double bonds of unsaturated fatty acids and alkenes. Finally, we discuss the use of che-mometric techniques due to increasing chemical information and the interest of combining molecular-level and stable isotope approaches.  相似文献   

18.
提出了一种海洋沉积物捕获器控制系统的软/硬件设计方案。该方案采用低功耗的硬件结构,多种冗余技术的软件设计, 满足了沉积物捕获器在海底可长达1 a 的低功耗、自动定时采集沉积物样品的要求。经过实验, 该控制系统运行可靠, 采样瓶切换控制准确, 运行数据记录完整, 具有广阔的应用前景。  相似文献   

19.
作为深海科学研究的重要基础装备,深海超长沉积物柱状取样系统在海底地形地貌、海洋地质构造、气候环境变化等研究领域发挥了重要作用,其在海底矿产资源勘探、海洋工程地质勘察等方面展现了巨大应用价值。针对传统超长柱状沉积物取样系统在作业过程中存在的盲目采样、安全隐患大、甲板作业空间受限等问题,自主研制了一套适用于深海的超长可控可视沉积物柱状取样系统,该系统具有液压锤击、立式收放和实时监控功能,能获取连续、超长、具有精准姿态方位信息的柱状沉积物样品。现通过对独立排缆方式、取样管快速拆装、样品封堵、低扰动取样刀头等关键技术细节进行优化,解决了样品扰动大、取样率低的问题,提高了取样作业效率与样品质量,且降低了作业安全风险。2017—2021年,该取样系统搭载不同母船在南海1 700,1 725 和1 778 m水深分别获取了15.25、16.01和15.83 m的长柱状沉积物样品。该设备的成熟应用,可为我国深海探测研究提供技术支持。  相似文献   

20.
Buoy-mooring platforms are advantageous for time-series validation and vicarious calibration of ocean color satellites because of their high temporal resolution and ability to perform under adverse weather conditions. Bio-optical data collected on the Bermuda Testbed Mooring (BTM) were used for comparison with satellite ocean color data in an effort to further standardize sampling and data processing methods for high quality satellite-mooring comparisons. Average percentage differences between satellite-measured and mooring-derived water leaving radiances were about 20% at the blue wavelengths, decreasing to as low as 11% in the blue-green to green wavebands. Based on a series of data processing methods and analyses, recommendations concerning rigor of quality control for collected data, optimal averaging of high-frequency data, sensor self-shading wind corrections, and instrumentation placement requirements are given for the design and application of optical moorings for ocean color satellite validation. Although buoy-mooring platforms are considered to be among the very best methods to validate ocean color satellite measurements, match-up discrepancies due to water column variability and atmospheric corrections remain important issues.  相似文献   

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