GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Coral mucus functions as an energy carrier and particle trap in the reef ecosystem (2004)
    [s.l.] : Macmillian Magazines Ltd.
    Nature 428 (2004), S. 66-70 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Zooxanthellae, endosymbiotic algae of reef-building corals, substantially contribute to the high gross primary production of coral reefs, but corals exude up to half of the carbon assimilated by their zooxanthellae as mucus. Here we show that released coral mucus efficiently traps organic ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/nature02344
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Activity and distribution of bacterial populations in Middle Atlantic Bight shelf sands (2003)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology ecology 44 (2003), S. 0 
    Details
    ISSN: 1574-6941
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Spatiotemporal variation and metabolic activity of the microbial community were studied in coarse-grained Middle Atlantic Bight shelf sediments in relation to pools of dissolved and particulate carbon. Algal cells were present 8–〉70 μm) fraction of the sediment held the major share (61–98%) of benthic bacteria. Bacterial and algal cell abundances, exoenzymatic activity, and [DOC] generally showed higher values in May/July 2001 than in August/December 2000. Carbohydrates and proteins were hydrolyzed at potential rates of 1–12 nmol cm−3 h−1 (β-glucosidase) and 3–70 nmol cm−3 h−1 (aminopeptidase), respectively. Fluorescence in situ hybridization analyses of the benthic microbes assigned 45–56% of DAPI-stained cells to Eubacteria and less than 2% to Eukarya. The prokaryotic community was dominated by planctomycetes and members of the Cytophaga/Flavobacterium cluster. Near the sediment surface, iodonitrotetrazolium violet reducing cells, that are considered actively respiring, amounted to 15–29% of total bacteria. Despite a low organic content (particulate organic carbon 〈0.03%) and relatively low bacterial abundances (〈109 cm−3), the Middle Atlantic Bight shelf sediments showed organic matter turnover rates that are comparable to those found in organic-rich finer-grained deposits. Our findings suggest a high biocatalytic filtration activity in these coarse permeable sediments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-6941.2003.tb01093.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Particle accumulation in a cylindrical sediment trap under laminar and turbulent steady flow: An experimental approach (1996)
    Springer
    Aquatic sciences 58 (1996), S. 297-326 
    Details
    ISSN: 1420-9055
    Keywords: Traps ; sediment traps ; trap calibration ; sinking-particle flux
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The hydrodynamical, fluid and particle parameters which control flushing rates, flow cells, and accumulation rates of particulate matter in cylindrical (MultiPIT) sediment traps were quantified in a flume simulation using a seeding technique for 25–45 µm particles. Particle collection was found to be a trap- and particle-specific filtering process encompassing advective and gravitational entry of particles over a reduced trap aperture area, and gravitational-turbulent removal of particles at the bottom of the internal flow cell. Trapping efficiency increased up to 10-fold with increasing horizontal flow velocity (1–30 cm · s−1). For given flow velocity, the trap over-and undercollected particles relative to their weight, i.e. (theoretical) Stokes settling velocity. The trapping efficiency increased with increasing trap Reynolds number ReT, changed by the approaching velocity in our experiments. Opposite findings from earlier experiments using the flume seeding technique and changing ReT by altering the trap diameter (Butman, 1986) are discussed. Semi-empirical equations are derived for the accumulation process of light, heavy and intermediate particles. From these, measured trap fluxes can be converted into in-situ verticle particle flux except for light particles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00877473
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    facet.materialart.
    Unknown
    Oxygen optodes as fast sensors for eddy correlation measurements in aquatic systems (2012)
    AMER SOC LIMNOLOGY OCEANOGRAPHY
    In:  EPIC3Limnology and Oceanography-Methods, AMER SOC LIMNOLOGY OCEANOGRAPHY, 10, pp. 304-316, ISSN: 1541-5856
    Details
    Publication Date: 2020-07-02
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 5
    facet.materialart.
    Unknown
    Benthic solute exchange and carbon mineralization in two shallow subtidal sandy sediments: Effect of advective pore-water exchange (2007)
    In:  EPIC3Limnology and Oceanography, 52(5), pp. 1943-1963, ISSN: 00243590
    Details
    Publication Date: 2017-03-10
    Description: We conducted four field campaigns to evaluate benthic O2 consumption and the effect of advective pore-water flow in nearshore permeable sediments in the North Sea and Baltic Sea. Advective pore-water transport had a marked effect on the benthic exchange of O2 and TCO2 in benthic chamber incubations, with the rates of exchange increasing by a factor of up to 2.5 when imposing flushing rates of 100-300 L m−2 d−1, compared to settings with diffusive exchange only. Estimates of in situ exchange rates using oxygen penetration and volumetric O2 consumption and TCO2 production rates were within the range measured in the chambers. The contribution of advection to solute exchange was highly variable and dependent on sediment topography. Advective processes also had a pronounced influence on the in situ distribution of O2 within the sediment, with characteristic two-dimensional patterns of O2 distribution across ripples, and also deep subsurface O2 pools, being observed. Mineralization pathways were predominantly aerobic when benthic mineralization rates were low and advective pore-water flow high as a result of well-developed sediment topography. By contrast, mineralization proceeded predominantly through sulfate reduction when benthic mineralization rates were high and advective pore-water flow low as a result of poorly developed topography. Previous studies of benthic mineralization in shallow sandy sediments have generally ignored these dynamics and, hence, have overlooked crucial aspects of permeable sediment function in coastal ecosystems.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 6
    facet.materialart.
    Unknown
    Near-bottom performance of the Acoustic Doppler Velocimeter (ADV) – a comparative study (2006)
    In:  EPIC3Aquatic Ecology, 40(4), pp. 481-492, ISSN: 1386-2588
    Details
    Publication Date: 2017-03-06
    Description: In a laboratory flume, a comparative study on the near-bottom performance of the Acoustic Doppler Velocimeter (ADV) was conducted. Two different ADV systems were tested for different configurations and two flow velocities (9 cm s−1, 18 cm s−1). The results were compared with synchronous measurements with a Laser Doppler Anemometer (LDA). Near-bottom velocity measurements with the ADV have to be interpreted carefully as the ADV technique underestimates flow velocities in a zone close to the sediment. The height of this zone above the sediment varies with different ADV systems and configurations. The values for nominal sampling volume height (SVH) given by the software often underestimate the true, effective sampling volume heights. Smaller nominal SVH improve the ADV near-bottom performance, but the vertical extent of the zone in which the ADV underestimates flow by more than 20% may be larger than true SVH/2 by a factor of 2 (=true SVH). When the measurement volume approaches the bottom, ADV data quality parameters (signal-to-noise-ratio (SNR) and signal amplitude) exceeding the average ‘open water’ level, are clear indicators that the ADV has begun to underestimate the flow velocity. Unfortunately, this is not a safe indicator for the range of reliable measurements as the ADV may begin to underestimate velocities even with unchanged ‘open water’ data quality parameters. Thus, one can only recommend avoiding measurements below a distance from the bottom that was defined empirically comparing the ADV and the LDA velocity profiles. This distance is 2.5 times nominal sampling volume height for the tested ADV systems and experimental settings.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 7
    facet.materialart.
    Unknown
    Decomposition of diatoms and nutrient dynamics in permeable North Sea sediments (2004)
    In:  EPIC3Continental Shelf Research, 24(6), pp. 721-737, ISSN: 02784343
    Details
    Publication Date: 2017-03-06
    Description: This study addresses the decomposition of diatoms in different permeable North Sea sand beds. During three cruises in 2001 to the southern German Bight, the regeneration of nutrients was assessed after the experimental deposition of organic matter corresponding to a typical spring diatom bloom in in situ and on-board chamber experiments. The diatom pulse was followed by a high regeneration of nutrients during the first day: 5–10% d−1 of the added nitrogen was converted to NH4+ and up to 0.67% d−1 of the added biogenic silica was dissolved to Si(OH)4. These results are used to interpret the response of pore water nutrient concentrations in permeable North Sea sands to seasonal nutrient and phytoplankton dynamics in the water column. The rapid advective solute exchange in these permeable sediments reduces the accumulation of regenerated nutrients, and, thus pore water concentrations of Si(OH)4, PO43− and NH4+ decreased with increasing permeability. All sands were characterized by relatively high NO3− concentrations down to 10 cm sediment depth, indicating that the upper sediment layers are oxidized by advective flushing of the bed. Our results demonstrate that biogenic silica and organic matter are rapidly degraded in permeable coastal sands, revealing that these sediments are very active sites of nutrient recycling.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 8
    facet.materialart.
    Unknown
    Eddy correlation measurements of oxygen fluxes in permeable sediments exposed to varying current flow and light (2014)
    Association for the Sciences of Limnology and Oceanography
    Details
    Publication Date: 2022-05-26
    Description: Author Posting. © Association for the Sciences of Limnology and Oceanography, 2013. This article is posted here by permission of Association for the Sciences of Limnology and Oceanography for personal use, not for redistribution. The definitive version was published in Limnology and Oceanography 58 (2013): 1329–1343, doi:10.4319/lo.2013.58.4.1329.
    Description: Based on noninvasive eddy correlation measurements at a marine and a freshwater site, this study documents the control that current flow and light have on sediment–water oxygen fluxes in permeable sediments. The marine sediment was exposed to tidal-driven current and light, and the oxygen flux varied from night to day between −29 and 78 mmol m−2 d−1. A fitting model, assuming a linear increase in oxygen respiration with current flow, and a photosynthesis–irradiance curve for light-controlled production reproduced measured fluxes well (R2 = 0.992) and revealed a 4-fold increase in oxygen uptake when current velocity increased from ∼ 0 to 20 cm s−1. Application of the model to a week-long measured record of current velocity and light showed that net ecosystem metabolism varied substantially among days, between −27 and 31 mmol m−2 d−1, due to variations in light and current flow. This variation is likely typical of many shallow-water systems and highlights the need for long-term flux integrations to determine system metabolism accurately. At the freshwater river site, the sediment–water oxygen flux ranged from −360 to 137 mmol m−2 d−1. A direct comparison during nighttime with concurrent benthic chamber incubations revealed a 4.1 times larger eddy flux than that obtained with chambers. The current velocity during this comparison was 31 cm s−1, and the large discrepancy was likely caused by poor imitation by the chambers of the natural pore-water flushing at this high current velocity. These results emphasize the need for more noninvasive oxygen flux measurements in permeable sediments to accurately assess their role in local and global carbon budgets.
    Description: Support for this study was provided by the following National Science Foundation grants: OCE-0420575, OCE- 0536431, and OCE-1061364.
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 9
    facet.materialart.
    Unknown
    Current flow and oxygen concentrations recorded by the 2OEC-instrument in the Florida Keys from August 2013 and April 2014 (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-05-26
    Description: Dataset: 2OEC-instrument
    Description: Velocity and external sensor data recorded by the Nortek Vector ADV logger in the Florida Keys from August 2013 and April 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/812523
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1334117, NSF Division of Ocean Sciences (NSF OCE) OCE-1334848
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 10
    facet.materialart.
    Unknown
    Temperature and dissolved oxygen recorded two PME Mindot O2 loggers in the Florida Keys from 11-17 July 2017 (2021)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-05-26
    Description: Dataset: 3OEC-instrument Temperature and Dissolved Oxygen
    Description: This dataset presents the temperature and oxygen data recorded by the two PME Minidot loggers. The loggers were deployed July 11-17, 2017 in a subtropical inner shelf environment (Salinity: 35-36, temperature: 28-31°C) approximately 9 km south of Long Key in the Florida Keys (24° 43.52'N, 80° 49.85'W). The site was located at 9 ± 1 m water depth near the center of a large flat carbonate platform covered with coral sand. The instruments were installed on the 3OEC instrument at ~35 cm above the sediment-water interface. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/849915
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1334117, NSF Division of Ocean Sciences (NSF OCE) OCE-1334848
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...