GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Articles  (12)
  • OceanRep  (5)
  • 2015-2019  (14)
  • 1995-1999  (3)
  • 1
    ISSN: 1573-5117
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract During two cruises to the Baltic (Mecklenburg Bight) in September 1993 and November 1994 bottom water and sediment samples were taken from 5 stations on a 2.0 km long transect above a benthic sandy silt community. Profiles of total particulate matter, particulate organic carbon, chlorophyll equivalents and urea were taken in the benthic boundary layer (5–40 cm height above sea floor) on the downstream stations across an area occupied by macrofauna feeding at the sediment-water interface at 26 m water depth. Particulate matter concentration profiles varied under the two different flow conditions in September ( u* = 0.7 cm s-1) and November (u* = 0.2 cm s-1). In September 1993 resuspension of total particulate matter (TPM) of 22 to 130 mg m-2 h-1 occurred while particulate organic carbon (POC) and chlorophyll (CPE) were deposited with a rate of 9 mg m-2 h-1 and 0.11 mg m-2 h-1 respectively at the station of highest macrofauna abundance. In November 1994 physical sedimentation and biological deposition of up to 388 mg m-2 h-1 TPM, 7.4 mg m-2 h-1 POC and 0.07 mg m-2 h-1 CPE occurred. Urea was released into the water column. Data suggest that in shallow water environments local sediment and benthic boundary layer characteristics prevent large scale calculations of fluxes of particulate matter.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 375-376 (1998), S. 265-285 
    ISSN: 1573-5117
    Keywords: Macrobenthos ; community structure ; continental slope ; flow velocity ; C/N ; NE Atlantic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Macrofauna density, biomass and community structure together with several characteristics of the sediment and flow velocity were estimated in May 1994 and August 1995 at seven stations ranging from 208 m to 4470 m water depth along the OMEX-transect in the Goban Spur area (NE Atlantic). In 1994 four additional stations were sampled at a parallel transect about 40 km SSE of the OMEX-transect. In 1995 two additional transects were sampled, one in the Porcupine Seabight ∼ 100 km NNW and one along the slope at ∼ 3500 m water depth situated ∼ 200 km SSE of the OMEX-transect. An overall trend in decrease in density and biomass with increasing water depth was found, but no depth related pattern in mean individual weight could be observed. Mean individual weight, however, did show a negative relationship with flow velocities. Correspondence-analyses and single linkage clustering of the community structure showed three more or less depth related clusters, representing a shelf community, an upper-slope and a lower-slope community. These clusters coincided with differences in grain-size, % organic C and total N within the sediment and differences in flow velocities. However, some of the stations at similar depths were not clustered together. Grain-size did not differ at stations with similar depth, but the % of C and N and flow velocities could differ markedly. Stations at similar depth, but with different physical and/or chemical conditions showed differences in density, biomass, mean individual weight and in macrobenthic community structure. More filter-feeding taxa were observed at stations with higher flow velocities, whereas more subsurface deposit-feeders were found at stations with higher sedimentation rates. Thus, besides the effects of water depth on macrobenthic community structure, other physical and chemical factors (such as flow velocities and organic matter supply) can be important structuring factors as well.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    Springer
    In:  In: Faszination Meeresforschung : ein ökologisches Lesebuch. , ed. by Hempel, G., Bischof, K. and Hagen, W. Springer, Heidelberg, Germany, pp. 179-210. 2. Aufl. ISBN 978-3-662-49713-5
    Publication Date: 2020-04-03
    Type: Book chapter , NonPeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2022-01-31
    Description: Increasing interest in the acquisition of biotic and abiotic resources from within the deep sea (e.g., fisheries, oil–gas extraction, and mining) urgently imposes the development of novel monitoring technologies, beyond the traditional vessel-assisted, time-consuming, high-cost sampling surveys. The implementation of permanent networks of seabed and water-column-cabled (fixed) and docked mobile platforms is presently enforced, to cooperatively measure biological features and environmental (physicochemical) parameters. Video and acoustic (i.e., optoacoustic) imaging are becoming central approaches for studying benthic fauna (e.g., quantifying species presence, behavior, and trophic interactions) in a remote, continuous, and prolonged fashion. Imaging is also being complemented by in situ environmental-DNA sequencing technologies, allowing the traceability of a wide range of organisms (including prokaryotes) beyond the reach of optoacoustic tools. Here, we describe the different fixed and mobile platforms of those benthic and pelagic monitoring networks, proposing at the same time an innovative roadmap for the automated computing of hierarchical ecological information on deep-sea ecosystems (i.e., from single species’ abundance and life traits to community composition, and overall biodiversity).
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2022-01-31
    Description: The anthropogenic impact of polymetallic nodule harvesting in the Clarion-Clipperton Fracture Zone is expected to strongly affect the benthic ecosystem. To predict the long-term, industrial-scale impact of nodule mining on the deep-sea environment and to improve the reliability of the sediment plume model, information about the specific characteristics of deep-sea particles is needed. Discharge simulations of mining-related fine-grained (median diameter ≈ 20 μm) sediment plumes at concentrations of 35–500 mg L–1 (dry weight) showed a propensity for rapid flocculation within 10 to 135 min, resulting in the formation of large aggregates up to 1100 μm in diameter. The results indicated that the discharge of elevated plume concentrations (500 mg L–1) under an increased shear rate (G ≥ 2.4 s–1) would result in improved efficiency of sediment flocculation. Furthermore, particle transport model results suggested that even under typical deep-sea flow conditions (G ≈ 0.1 s–1), rapid deposition of particles could be expected, which would restrict heavy sediment blanketing (several centimeters) to a smaller fall-out area near the source, unless subsequent flow events resuspended the sediments. Planning for in situ tests of these model projections is underway
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2022-01-31
    Description: Future mining of polymetallic nodules in the Clarion Clipperton Zone (Northeastern Pacific) is expected to affect all benthic ecosystems. The diversity, distribution, and environmental functions of microorganisms inhabiting abyssal sediments are barely understood. To understand consequences of deep-sea mining, experimental in vitro systems needs to be established to test hypotheses on the environmental impact of mining. For this, 40 bacterial strains, belonging to proteobacteria, actinobacteria and firmicutes were isolated from deep-sea sediments and nodules sampled at depths of ≥ 4000 m. Phenotypic characterization revealed a strong inter-species and moderate intra-species variability. Determination of metal minimum inhibitory concentrations indicated the presence of acute manganese-resistant bacteria such as Rhodococcus erythropolis (228.9 mM), Loktanella cinnabarina (57.2 mM), and Dietzia maris (14.3 mM) that might be suitable systems for testing the effects of release of microbes from nodules and their interactions with sediment particles in plumes generated during mining. Comparative genomic analysis indicated the presence of manganese efflux systems relevant for future transcriptomics or proteomics approaches with environmental samples and might serve in paving the way to develop model systems including representative organisms which are currently not cultivable. Monitoring deep-sea mining activity at abyssal depth is a challenge that has to be tackled. We proposed the use of API strips as a fast on-board methodology for bacterial monitoring as an indicator for sediment plume dispersions within the water column.
    Type: Article , PeerReviewed
    Format: text
    Format: other
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2023-07-12
    Type: Thesis , NonPeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2018-09-11
    Description: Hydrodynamic behaviour and the transport pathways of microplastics within the ocean environment are not well known, rendering accurate predictive models for dispersal management of such pollutants difficult to establish. In the natural environment, aggregation between plastic microbeads and phytodetritus or suspended sediments in rivers and oceans further complicate the patterns of dispersal. In this laboratory study, the physical characteristics and hydrodynamic behaviour of a selection of common plastic microbeads, as used in exfoliation skincare cosmetic products, were investigated. Additionally, the potential for aggregation of these microbeads with phytodetritus and suspended sediments, as well as the subsequent sinking and resuspension behaviour of produced aggregates, were investigated with roller tanks, settling columns and erosion chamber. Physical characteristics of the plastic microbeads showed great heterogeneity, with various densities, sizes and shapes of plastic material being utilised in products designed for the same purpose. The majority of the plastics investigated were positively buoyant in both freshwater and seawater. Aggregation between plastic microbeads and phytoplankton was observed to be swift, with even extremely high concentrations of plastics being rapidly scavenged by suspended algal material. Following aggregation to sizes of 300 to 4400 μm diameter, some formerly buoyant plastics were observed to settle through the water column and enter the benthic boundary layer with settling velocities ranging between 32 and 831 m day–1. These aggregates could be resuspended in the laboratory under critical shear velocities of 0.67–1.33 cm s–1 (free stream velocities of 〉 10 cm s–1). This rapid aggregation and subsequent settling indicates a potentially important transport pathway for these waste products, a pathway that should be considered when modelling discharge and transport of plastic microbeads and determining the ecosystems that may be at risk from exposure.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2017-01-20
    Description: Despite the technological advances of the last decades (e.g. ROVs, AUVs, cabled observatories), our knowledge of most deep-sea environments is still strongly limited by spatio-temporal sampling and observational capabilities. The novel Internet Operated Deep-Sea Crawler technology can provide high-frequency, multi-sensor data, during long-term deployments, 24/7 communication with researchers and broader spatial coverage (i.e. mobile platform) than fixed instrument installations. The crawler “Wally” is deployed at the Barkley Canyon methane hydrates site (NE Pacific, Canada; ~890 m depth) and connected to the Ocean Networks Canada NEPTUNE cabled observatory network (ONC; www.oceannetworks.ca). Here we present the environmental and biological datasets obtained from Wally instruments and cameras, during the first deployment phase (September 2010 to January 2015), as well as new features and preliminary results obtained since it was re-deployed (May 2016 – present). In addition to data provided by the standard payload of the crawler (i.e. ADCP, CTD, methane sensor, turbidity sensor and fluorometer), the hydrates community was video-monitored at different frequencies and timespans. Photomosaics were generated at two distinct locations, in order to map chemosynthetic bacterial mats and vesicomyid clam colonies covering the ~2-3 m high hydrate mounds, and document their temporal dynamics. The crawler followed the development of a deep-sea shell taphonomic experiment aiming to quantify biogenic carbon fluxes at the hydrates environment. The composition and diel activity patterns of the hydrates megafaunal community were studied with the use of linear video-transects conducted from February 2013 to April 2014. Since the summer of 2016, video-frames recorded at different locations of the site are analyzed for a biodiversity study and photomosaicing of the hydrate mounds continues, with 3D modelling of the mound structures also available as a new feature of the crawler deployed in May 2016. All data are archived in real-time and can be accessed online on the Ocean Networks Canada database. As deep-sea crawler technology and similar mobile, benthic platform technologies progress towards full operational autonomy, they will provide an even greater capacity for future monitoring and understanding of dynamic, extreme environments such as methane hydrate fields.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    facet.materialart.
    Unknown
    SPRINGER
    In:  EPIC3Faszination Meeresforschung, Faszination Meeresforschung, Heidelberg, SPRINGER, pp. 179-210, ISBN: 978-3-662-49714-5
    Publication Date: 2017-01-18
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...