ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Other Sources  (919)
  • Elsevier  (918)
  • Annual Reviews
  • 2005-2009  (652)
  • 1990-1994  (155)
  • 1985-1989  (75)
  • 1980-1984  (33)
  • 1965-1969  (4)
  • 1935-1939
Collection
Years
Year
  • 1
    facet.materialart.
    Unknown
    Elsevier
    In:  Signal Processing, Tokyo, Elsevier, vol. 8, no. 1, pp. 401-413, pp. L16603
    Publication Date: 1985
    Keywords: Spectrum ; Maximum likelihood
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 3, pp. 6322, (ISBN 0-521-79203-7)
    Publication Date: 1990
    Keywords: Textbook of geophysics ; Seismics (controlled source seismology) ; Applied geophysics ; Vibroseis
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 14 B, pp. 225, (ISBN 3-7643-7011-4)
    Publication Date: 1984
    Keywords: Applied geophysics ; seismic Migration ; Seismics (controlled source seismology) ; Acoustics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 3, pp. 6322, (ISBN 0-521-79203-7)
    Publication Date: 1989
    Keywords: Textbook of physics ; Textbook of geophysics ; Stress ; Boundary Element Method
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    facet.materialart.
    Unknown
    Elsevier
    In:  New York, Elsevier, vol. 138, no. 2, pp. 125-169, (ISBN 0-7923-5034-0)
    Publication Date: 1987
    Keywords: Borehole geophys. ; Textbook of geophysics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, 432 pp., Elsevier, vol. 167, no. XVI:, pp. 385-389, (ISBN 1-56670-263-3)
    Publication Date: 1994
    Keywords: 93.1060 ; Crustal deformation (cf. Earthquake precursor: deformation or strain) ; Textbook of geophysics ; Plate tectonics ; Fracture ; Tectonics ; Geol. aspects ; Rheology ; Stress ; cracks and fractures (.NE. fracturing) ; salt
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, 652 pp., Elsevier, vol. 39, no. XVI:, pp. 227-235, (0-444-51955-6)
    Publication Date: 1989
    Keywords: Borehole geophys. ; Textbook of geophysics ; Dual Induction Latero log
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. Developments in Petroleum Science vol. 15B, no. Publ. No. 12, pp. 9, (ISBN: 0-12-636380-3)
    Publication Date: 1986
    Keywords: Borehole geophys. ; Textbook of geophysics ; Tectonics ; Geol. aspects ; GFZ ; RUB ; GMG ; 3.45.8 ; UniL ; IfGuG ; in ; Französisch
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. Developments in Petroleum Science vol. 15A, no. Publ. No. 12, pp. 9, (ISBN: 0-12-636380-3)
    Publication Date: 1984
    Keywords: Borehole geophys. ; Textbook of geophysics ; GFZ ; RUB ; GMG ; 3.45.8 ; UniL ; IfGuG ; in ; Französisch
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 26, no. ALEX(01)-FR-77-01, AFTAC Contract F08606-76-C-0025, pp. 329, (ISBN: 0-08-043649-8)
    Publication Date: 1987
    Keywords: Seismology ; Seismics (controlled source seismology) ; Applied geophysics ; Layers
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, 253 pp., Elsevier, vol. 10, no. 1, pp. 1-40, (ISBN: 3-540-23712-7)
    Publication Date: 1983
    Keywords: Textbook of geophysics ; Acoustics ; Seismics (controlled source seismology) ; Waves ; Wave propagation
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Open-File Rept., Ground Motion and Engineering Seismology, Amsterdam, Elsevier, vol. 14, no. 86-425, pp. 231-241, (ISBN 0080419208)
    Publication Date: 1987
    Keywords: Seismology ; Strong motions
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Open-File Rept., The Origin of Arcs, Amsterdam, Elsevier, vol. 65, no. 1, pp. 63-78, (ISBN 0080419208)
    Publication Date: 1986
    Keywords: Tectonics ; Geol. aspects ; Fault zone ; Plate tectonics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    facet.materialart.
    Unknown
    Elsevier
    In:  Advances in Geophysics, ed.: Renata Dmowska, Warszawa, Elsevier, vol. 47, no. 7, pp. 65-111, pp. L21303, (ISBN: 0-12-018847-3)
    Publication Date: 2005
    Keywords: Fault zone ; Rock mechanics ; Friction ; Fracture ; Physical properties of rocks ; geometry
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    facet.materialart.
    Unknown
    Elsevier
    In:  Advances in Geophysics, ed.: Renata Dmowska, Heidelberg, Elsevier, vol. 47, no. 8, pp. 1-64, pp. 1516, (ISBN: 0-12-018847-3)
    Publication Date: 2005
    Keywords: Crustal deformation (cf. Earthquake precursor: deformation or strain) ; Subduction zone ; USA
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 12, pp. 225, (ISBN 3-7643-7011-4)
    Publication Date: 1985
    Keywords: Textbook of geophysics ; Seismics (controlled source seismology) ; seismic Migration ; Acoustics ; Wave propagation ; Waves
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 6, no. 16, pp. 220, (ISBN: 3540148477)
    Publication Date: 1989
    Keywords: Fracture ; Rock mechanics ; Elasticity
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 81A and 81B, no. 22, pp. 65-70, (1405101733, 336 p.)
    Publication Date: 1984
    Keywords: Textbook of geophysics ; Earth model, also for more shallow analyses !
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, 566+XIII pp., Elsevier, vol. 65, no. ALEX(01)-FR-77-01, AFTAC Contract F08606-76-C-0025, pp. 95-104, (ISBN: 0-08-044051-7)
    Publication Date: 1986
    Keywords: Elasticity theory of dislocations ; Textbook of geophysics ; Dislocation
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, 613 pp., Elsevier, vol. 52, no. ALEX(01)-FR-77-01, AFTAC Contract F08606-76-C-0025, pp. 95-104, (ISBN: 0-08-044051-7)
    Publication Date: 1987
    Keywords: Inversion ; Textbook of mathematics ; Textbook of geophysics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 65, no. ALEX(01)-FR-77-01, AFTAC Contract F08606-76-C-0025, pp. 95-104, (ISBN: 0-08-044051-7)
    Publication Date: 1989
    Keywords: Textbook of geophysics ; Gravimetry, Gravitation ; Crustal deformation (cf. Earthquake precursor: deformation or strain)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Polar Proj. OP-O3A4, Signal Processing II: Theories and Applications, Bath, Elsevier, vol. 186, no. XVI:, pp. 689-692, (ISBN: 3-540-23712-7)
    Publication Date: 1983
    Keywords: Seismology ; Seismic arrays ; Spectrum ; Broad-band ; Data analysis / ~ processing ; f-k-Analysis ; Schuessler ; Schussler
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Polar Proj. OP-O3A4, Signal Processing II: Theories and Applications, Leiden, Elsevier, vol. 11, no. XVI:, pp. 673-680, (ISBN: 3-540-23712-7)
    Publication Date: 1983
    Keywords: Seismology ; Seismics (controlled source seismology) ; Filter- ; Data analysis / ~ processing ; Schuessler ; Schussler
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Polar Proj. OP-O3A4, Computer-aided Seismic Analysis and Discrimination, London, Elsevier, vol. 16, no. 4, pp. 97-109, (ISBN 0080419208)
    Publication Date: 1981
    Keywords: Group veloc. ; Velocity analysis
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 54, no. XVI:, pp. 9-66, (ISBN: 3486274473, 2. Auflage 2004, xxiv, 244 Seiten)
    Publication Date: 1992
    Keywords: FractureT ; Geol. aspects ; Seismicity ; Statistical investigations
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 1, no. 22, pp. 65-70, (ISBN 3-7643-0253-4)
    Publication Date: 1990
    Keywords: Seismology ; Textbook of geophysics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, I-VII + 329 pp., Elsevier, vol. 1, no. Publ. No. 12, pp. 127, (ISBN 3-540-44363-0)
    Publication Date: 1980
    Keywords: Geothermics ; application ; and ; prospection ; Earthquake hazard ; nuclear ; power ; plants ; Earthquake risk ; solar ; Energy (of earthquakes) ; pollution ; FROTH ; pp. ; 1-81, ; 279-288
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 20, no. Publ. No. 12, pp. 23-40, (ISBN 3935922167)
    Publication Date: 1986
    Keywords: Textbook of geophysics ; Data analysis / ~ processing ; Elasticity
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 65, no. ALEX(01)-FR-77-01, AFTAC Contract F08606-76-C-0025, pp. 95-104, (ISBN: 0-08-044051-7)
    Publication Date: 1993
    Keywords: Textbook of geophysics ; GeodesyY ; Geothermics ; Planetology ; ConvolutionE
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 2, no. 1, pp. 1-40, (ISBN 3-7643-6675-3)
    Publication Date: 1989
    Keywords: Textbook of geophysics ; Seismics (controlled source seismology) ; Applied geophysics ; Data analysis / ~ processing
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Polar Proj. OP-O3A4, Fractals in Physics, Amsterdam, Elsevier, vol. 24, no. 4, pp. 177-180, (ISBN 0080419208)
    Publication Date: 1986
    Keywords: Fracture ; FractureT
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Polar Proj. OP-O3A4, The Origin of Arcs, Amsterdam, Elsevier, vol. 13, no. Subvol. a, pp. 93-113, (ISBN 0080419208)
    Publication Date: 1986
    Keywords: CRUST ; earth mantle ; Plate tectonics ; Muller
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier
    Publication Date: 1980
    Keywords: Seismology ; Seismics (controlled source seismology) ; Wave propagation ; Waves ; Textbook of geophysics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 1, pp. 225, (ISBN 3-7643-7011-4)
    Publication Date: 1987
    Keywords: Textbook of geophysics ; Applied geophysics ; Seismics (controlled source seismology)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, 652 pp., Elsevier, vol. 39, no. XVI:, pp. 227-235, (0-444-51955-6)
    Publication Date: 2005
    Keywords: Seismics (controlled source seismology) ; Applied geophysics ; Wave propagation ; plane ; spherical ; and ; cylindrical ; Waves ; in ; isotropic ; and ; transversely ; isotropic ; solids, ; liquid-solid ; models, ; and ; media ; with ; cylindrical ; inclusions ; (boreholes) ; Textbook of geophysics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 16, no. 22, pp. 662-664, (ISBN 0-470-87000-1 (HB), ISBN 0-470-87001-X (PB))
    Publication Date: 1987
    Keywords: Surface waves ; Seismology ; Textbook of geophysics ; Wave propagation
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 16, no. 1, pp. 662-664, (ISBN 0-470-87000-1 (HB), ISBN 0-470-87001-X (PB))
    Publication Date: 1988
    Keywords: Textbook of geology ; Tectonics ; Fault zone ; Stress ; Fracture ; Engineering geophys.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    facet.materialart.
    Unknown
    Elsevier
    In:  Amsterdam, Elsevier, vol. 31, no. 1, pp. 1-40, (ISBN 0-691-01019-6)
    Publication Date: 1994
    Keywords: Textbook of geophysics ; Geoelectrics ; Applied geophysics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Polar Proj. OP-O3A4, Continental Lower Crust, Amsterdam, Elsevier, vol. 4, no. Subvol. b, pp. 45, (ISBN 0080419208)
    Publication Date: 1992
    Keywords: Reflectivity ; Review article ; Reflection seismics ; CRUST ; Meissner
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Open-File Rept., Continuum Theories in Solid Earth Physics, Amsterdam, 566+XIII pp., Elsevier, vol. 186, no. 16, pp. 18-186, (ISBN 0080419208)
    Publication Date: 1986
    Keywords: Elasticity theory of dislocations ; Dislocation ; Review article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    facet.materialart.
    Unknown
    Elsevier
    In:  Bull., Open-File Rept., Signal Processing II: Theories and Applications, Orlando, Elsevier, vol. 37, no. 16, pp. 681-684, (ISBN 1-86239-165-3, vi + 330 pp.)
    Publication Date: 1983
    Keywords: Detectors ; Seismic arrays ; Seismology ; Schuessler ; Schussler
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    facet.materialart.
    Unknown
    Elsevier
    In:  Professional Paper, Open-File Rept., Thermodynamics of Point Defects and the Relation with Bulk Properties, New York, Elsevier, vol. 1, no. 16, pp. 410-412, 417-420, (ISBN 0080419208)
    Publication Date: 1986
    Keywords: Geomagnetics ; Earthquake precursor: prediction research ; Earthquake precursor: magnetic ; Geoelectrics ; Physical properties of rocks
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    facet.materialart.
    Unknown
    Elsevier
    In:  Fisheries Research, 8 (1). pp. 35-44.
    Publication Date: 2017-01-10
    Description: In Moreton Bay, Queensland, the catch obtained using monofilament polyamide (PA) otter trawl-nets with multifilament polyethylene (PE) cod ends was compared with that obtained using multifilament PE trawl-nets of identical mesh opening (38 mm). Monofilament PA otter trawl-nets retained fewer small prawns ( 〈 24 mm carapace length) than conventional multifilament PE nets, but both nets caught similar quantities of larger prawns ( 〉 24 mm carapace length). The higher retention rate of small prawns by multifilament PE gear was reflected in the greater catch weights of Peraeus plebejus, Metapenaeus bennettae and Metapenaeopsis novaeguineae in those nets. Catch weights of larger prawn species such as Penaeus esculentus and Metapenaeus endeavouri did not differ between nets. Winter whiting (Sillago maculata) and squid (Loligo spp.) were trawled in similar abundance in both nets, although the monofilament retained fewer squid 〈 50 mm mantle length. More marketable ( 〉 15 cm carapace width) sand crabs (Portunus pelagicus) were caught in the monofilament net. There was not significant difference in the trash (noncommercial component) weight caught in both nets. Over the range of towing speeds tested (1.7–2.3 kn), use of monofilament nets significantly reduced total gear drag.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2020-07-31
    Description: Distribution and abundance of the horned octopus Eledone cirrhosa in the Tyrrhenian Sea are described on the basis of stratified-random bottom trawl surveys in spring and summer of the years 1985–1987. Specimens were caught between 25 and 630 m depth (higher densities between 50 and 200 m depth); mature males were found to prefer deeper bottoms than mature females. Young specimens occurred in spring samples from the Western Ligurian Sea and in summer samples from the Lower Tyrrhenian Sea, but were scarcely represented in the Higher Tyrrhenian Sea. Thus recruitment seems to be progressively delayed later in the season from north to south. The greatest abundance was recorded in the Higher Tyrrhenian Sea; wide seasonal variations of minimum stock biomass estimates have been observed and total biomass decreased from 1985 to 1987 in the surveyed areas.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    facet.materialart.
    Unknown
    Elsevier
    In:  Journal of Experimental Marine Biology and Ecology, 163 (2). pp. 261-276.
    Publication Date: 2017-03-29
    Description: An investigation was carried out on the morphology, growth and microstructure of statoliths of 833 specimens of Sthenoteuthis pteropus (Steenstrup) mantle length (ML): 2–548 mm collected in the open waters of the Gulf of Guinea in 1984–1988. Statolith morphology is similar to that of other species of the subfamily Ommastrephinae and is similar to the sibling species S. oulaniensis. Statolith development includes five stages resembling those of Illex illecebrosus and other ommastrephids. Statolith growth is characterized by negative allometry. Increments visible in ground sections of statoliths can be grouped into four main growth zones, differing mainly in colour and increment width. Age and growth rates of S. pteropus were calculated using increment counts. The life span of females of all size groups does not exceed 1 yr, that of males is 1–2 months shorter, probably due to preliminary mating. Instantaneous relative growth rage (G) of paralarvae is high (up to 16% of body weight (BW)). G values for juveniles decline, but remain relatively high (7–8% BW). Juveniles attain 100–110 mm ML by age 100–110 days. G values for adults are the lowest (1.8–2% BW), but daily growth rates reach maximum values (40–70 g per day in large females of 450–500 mm ML). Each ontogenetic phase of S. pteropus corresponds to features of morphology, growth and microstructure of the statolith.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2020-05-14
    Description: The volcanic arc of the Hellenic subduction zone with its four volcanic centers is of major relevance when evaluating the seismovolcanic hazard for the Aegean region. We present results from a 22-station temporary seismic network (CYCNET) in the central Hellenic Volcanic Arc (HVA). CYCNET recordings allow to analyze the level and spatio-temporal evolution of microseismic activity in this region for the first time. A total of 2175 events recorded between September 2002 and July 2004 are analyzed using statistical methods, cluster analysis and relative relocation techniques. We identify distinct regions with significantly varying spatiotemporal behavior of microseismicity. A large portion of the seismic activity within the upper crust is associated with the presence of islands representing horst structures that were generated during the major Oligocene extensional phase. In contrast, the central part of the Cyclades metamorphic core complex remains aseismic considering our magnitude threshold of 1.8 except one spot where events occur swarm-like and with highly similar waveforms. The highest activity in the study area was identified along the SW–NE striking Santorini–Amorgos zone. Within this zone the submarine Columbo volcano exhibits strong temporal variations of seismic activity on a high background level. This activity is interpreted to be directly linked to the magma reservoir and therein the migration of magma and fluids towards the surface. NE of Columbo where no volcanic activity has yet been reported we observe a similar seismicity pattern with small-scaled activity spots that might represent local pathways of upward migrating fluids or even developing volcanic activity within this zone of crustal weakness. In contrast, the Santorini and Milos volcanic complexes do not show significant temporal variations and low to moderate background activity, respectively. Relating our results to the distribution of historical earthquakes and the GPS-derived horizontal velocity field we conclude that the Santorini–Amorgos zone is presently in the state of right-lateral transtension reflecting a major structural boundary of the volcanic arc subdividing it into a seismically and volcanically quiet western and an active eastern part.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2020-06-03
    Description: Mean intracellular pH (pHi) and PCO2 (PiCO2) have been analysed based on pH and total CO2 measurements in tissue homogenates. Tissues were sampled from undisturbed worms (Sipunculus nudus), squid (Illex illecebrosus), trout (Salmo gairdneri), toads (Bufo marinus), and rats. Homogenate metabolism was inhibited by the addition of potassium fluoride and nitrilotriacetic acid (NTA). Model calculations revealed that the influence of dilution, medium buffers, and contamination by extracellular fluids was negligible. In white muscle tissue the resulting pHi values were virtually the same as found in studies using DMO (dimethyloxazolidinedione). If large fractions of mitochondria were present (e.g. in heart muscle), DMO derived pHi values were considerably higher, probably representing overestimates. Homogenate derived pHi values are concluded to represent the effective mean pHi by taking into account pH gradients, and the volumes and buffering of cellular compartments. High time resolution and small variability make this method especially useful to assess rapid changes in pHi, e.g. in exercising animals.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    facet.materialart.
    Unknown
    Elsevier
    In:  Journal of Experimental Marine Biology and Ecology, 177 (1). pp. 73-78.
    Publication Date: 2020-07-27
    Description: The periodicity of deposition of growth increments in the cuttlebone of juvenile Sepia officinalis was investigated under controlled conditions for a short period after hatching (19 days). The slope of time elapsed and increment counts was significantly different from 1 indicating that lamellae are not deposited on a daily basis. The relationship between increment counts and juvenile length was, however, highly significant. Also significant were the relationships between the number of growth increments and shell length and increment counts and cuttlebone area. These data show that the number of growth increments is related primarily to the growth rate of the juvenile rather than to its chronological age. Taking into account these data, the cuttlebone lamellae cannot be used for age determination in the juvenile cuttlefish just after hatching.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    facet.materialart.
    Unknown
    Elsevier
    In:  Organic Geochemistry, 39 (8). pp. 1000-1006.
    Publication Date: 2017-06-26
    Description: The anaerobic oxidation of methane (AOM), by converting methane to bicarbonate which is then precipitated as extensive carbonate crusts, is an important methane sink in the Earth’s ocean systems. Here we employ a multidisciplinary approach to investigate the role of microorganisms in carbonate precipitation using biomarker analysis, scanning electron microscopy (SEM) and X-ray diffraction. We examined two microbial mats from the Black Sea and found that one comprised carbonate in both aragonite and Mg calcite forms and most likely ANME-1 archaea, whereas the other contained only Mg calcite and most likely ANME-2 archaea. We conclude, as have others, that the different microbial communities could impart different influences on carbonate mineralogy and morphology. Although further research is needed, this is a contribution to our understanding of those relationships, which could prove critical in the interpretation of ancient sedimentary deposits.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2017-06-27
    Description: There is growing concern about the transfer of methane originating from water bodies to the atmosphere. Methane from sediments can reach the atmosphere directly via bubbles or indirectly via vertical turbulent transport. This work quantifies methane gas bubble dissolution using a combination of bubble modeling and acoustic observations of rising bubbles to determine what fraction of the methane transported by bubbles will reach the atmosphere. The bubble model predicts the evolving bubble size, gas composition, and rise distance and is suitable for almost all aquatic environments. The model was validated using methane and argon bubble dissolution measurements obtained from the literature for deep, oxic, saline water with excellent results. Methane bubbles from within the hydrate stability zone (typically below 500 m water depth in the ocean) are believed to form an outer hydrate rim. To explain the subsequent slow dissolution, a model calibration was performed using bubble dissolution data from the literature measured within the hydrate stability zone. The calibrated model explains the impressively tall flares (〉1300 m) observed in the hydrate stability zone of the Black Sea. This study suggests that only a small amount of methane reaches the surface at active seep sites in the Black Sea, and this only from very shallow water areas (〈100 m). Clearly, the Black Sea and the ocean are rather effective barriers against the transfer of bubble methane to the atmosphere, although substantial amounts of methane may reach the surface in shallow lakes and reservoirs.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2018-03-07
    Description: Structure-based inhibitor design has led to the discovery of a number of potent inhibitors of glycogen phosphorylase b (GPb), N-acyl derivatives of β-d-glucopyranosylamine, that bind at the catalytic site of the enzyme. The first good inhibitor in this class of compounds, N-acetyl-β-d-glucopyranosylamine (NAG) (Ki = 32 μM), has been previously characterized by biochemical, biological and crystallographic experiments at 2.3 Å resolution. Bioisosteric replacement of the acetyl group by trifluoroacetyl group resulted in an inhibitor, N-trifluoroacetyl-β-d-glucopyranosylamine (NFAG), with a Ki = 75 μM. To elucidate the structural basis of its reduced potency, we determined the ligand structure in complex with GPb at 1.8 Å resolution. To compare the binding mode of N-trifluoroacetyl derivative with that of the lead molecule, we also determined the structure of GPb–NAG complex at a higher resolution (1.9 Å). NFAG can be accommodated in the catalytic site of T-state GPb at approximately the same position as that of NAG and stabilize the T-state conformation of the 280s loop by making several favourable contacts to Asn284 of this loop. The difference observed in the Ki values of the two analogues can be interpreted in terms of subtle conformational changes of protein residues and shifts of water molecules in the vicinity of the catalytic site, variations in van der Waals interaction, and desolvation effects.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    facet.materialart.
    Unknown
    Elsevier
    In:  Journal of Experimental Marine Biology and Ecology, 162 (2). pp. 229-241.
    Publication Date: 2018-03-16
    Description: The presented data on indirect and direct calorimetry in Halicryptus spinulosus, a species with prominent ecological significance in parts of the Baltic Sea, provide a basis for a better understanding of the metabolic adaptation of these animals to low oxygen availability in their environment. Metabolic rates in H. spinulosus were measured respirometrically as oxygen consumption and calorimetrically as heat dissipation. Oxygen uptake rates are in the range of M O2 = 3.81 ± 1.37 μmol O2·g−1 dry mass·h−1. Upon reimmersion into normoxic seawater after an anoxic incubation of 7 days, the animals exhibit an overshoot of oxygen consumption by a factor of 2.4. It takes at least 2 days for the animals to balance their oxygen consumption to previously measured rates. Direct calorimetry exhibits different strategies of H. spinulosus to cope with declining oxygen and anoxia. During the first 2 transitional days to anoxia in the calorimeter, the animals decreased heat dissipation moderately down to 53.4 and 26%, respectively, of aerobic values. The animals are not necessarily quiescent at the beginning of anoxia, but at the end of the experiments after 14 days metabolic rates have dropped substantially down to ≈2% of normoxic values. These findings are discussed with regard to an effective adaption to frequently changing oxygen regimes in deeper parts of the Baltic Sea.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2018-03-15
    Description: CO2 partial pressure in surface water was measured in the Northeast Atlantic and in the Hebride Shelf/North Sea area during a cruise with R.V. Poseidon in June 1991. A mean pCO2 of 303 μatm was found in the Atlantic between 50°N and 60°N. For an atmospheric CO2 content of 357.5 ppm(v) this corresponds to a partial pressure difference of −55 μatm. This supports the view that the subarctic Atlantic is a significant sink within the CO2 cycle between the ocean and the atmosphere. A comparison of our measurements with other data reveals that the pCO2 distribution changes significantly during May/June. This explained by seasonal warming, CO2 exchange with the atmosphere and biomass production. The contribution by each of these processes to the seasonal variations is calculated. It was found that during a plankton bloom the production of biomass is the dominating factor and may lower seawater pCO2 by almost 100 μatm. The shelf areas are charactrized by strong pCO2 gradients which are explained by water exchange with the Atlantic, temperature effects and biomass production.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    facet.materialart.
    Unknown
    Elsevier
    In:  Marine Pollution Bulletin, 26 (3). pp. 152-155.
    Publication Date: 2018-03-22
    Description: Skin and hair samples of harbour seals (Phoca vitulina) found dead along the west coast of northern Germany in 1988 were analysed for total mercury, cadmium and lead. Cadmium and lead concentrations were below the detection limit in most skin samples. The mercury content of the hair (median: 23.1 μg g−1 wet wt) was several magnitudes higher than the mercury content of the skin (0.27 μg g−1 wet wt). Mercury concentrations in hair samples were significantly higher than lead concentrations (0.54 μg g−1 wet wt), which significantly exceeded cadmium levels (0.09 μg g−1 wet wt). Female seals revealed lower cadmium concentrations in the hair than male seals. Accumulations of metals with age were observed for cadmium and lead in hair samples and for mercury in skin samples of male seals. A connection between metal accumulation and pigmentation or rather moult was clearly recognizable.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    facet.materialart.
    Unknown
    Elsevier
    In:  Deep Sea Research Part I: Oceanographic Research Papers, 40 (2). pp. 267-291.
    Publication Date: 2018-03-22
    Description: The spreading of Mediterranean Water (MW) released through the Straits of Gibraltar is studied with hydrographic data, oxygen, nutrients and for the first time with chlorofluoromethane (CFM, compounds F11 and F12) distributions along seven sections in the Gulf of Cadiz, and with measurements in the Western Alboran Sea and west of the Gulf. The properties of MW entering the Gulf are deduced from CFM-salinity correlations east and west of the Straits as well as from property-depth profiles in the Western Alboran Sea. At the time of the survey, the outflow originated from depths above the salinity maximum of the Intermediate Water in the Alboran Sea. It turned out that the F11/F12 ratio of the outflow is equal to the ratios found in the Atlantic water in the Gulf of Cadiz; thus the ratio carries no time information in the region. A model is developed to describe mixing of the MW undercurrent with overlying North Atlantic Central Water (NACW) from different depths. The contribution of each layer to the mixing is parameterized by a weighting factor, which has to satisfy the balances of potential temperature (θ), CFMs, oxygen and nutrients in the MW undercurrent. It is shown that entrainment of water from shallower depths into the undercurrent is important near the Iberian Continental Shelf. Farther west and south, the undercurrent mainly mixes with water from near the salinity minimum of the NACW. For regions where the undercurrent has left the bottom, additional mixing with North Atlantic Deep Water (NADW) has to be taken into account. The percentage of MW in the undercurrent decreases from 76% hear the Straits to about 34% at 7°30′W for the lower core (MI) and about 22–24% for the upper core (Mu). Assuming an outflow of undiluted MW through the Straits of 1.0 Sv, the transport of the undercurrent can be calculated by determining an average dilution factor for each section. The undercurrent transports 2.0 Sv just west of the Straits and 3.6 Sv leave the Gulf of Cadiz. At 36°N, 9°54′W, a meddy with unusually high temperatures and salinities below 500 m was found, covering the density range for both cores, Mu and Ml. From the θ−S characteristics and the evaluated mixing scheme of the meddy it appears to have formed near 7°W in the Gulf, a region up to now not proposed in the literature, and moved westward without much further mixing.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    facet.materialart.
    Unknown
    Elsevier
    In:  Advances in Parasitology, 68 . pp. 111-137.
    Publication Date: 2020-04-23
    Type: Article , PeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2020-07-28
    Description: Carbohydrates on parasite surfaces have been shown to play an important role in host–parasite coevolution, mediating host non-self recognition and parasite camouflage. Parasites that switch hosts can change their surface molecules to remain undetected by the diverse immune systems of their different hosts. However, the question of individual variation in surface sugar composition and its relation to infectivity, virulence, immune evasion and growth of a parasite in its different hosts is as yet largely unexplored. We studied such fitness consequences of variation in surface sugars in a sympatric host–parasite system consisting of the cestode Schistocephalus solidus and its intermediate hosts, a copepod and the three-spined stickleback. Using lectins to analyse the sugar composition, we show that the tapeworm changes its surface according to the invertebrate or vertebrate host. Importantly, sugar composition seems to be genetically variable, as shown by differences among tapeworm sibships. These differences are related to variation in parasite fitness in its second intermediate host, i.e. infectivity and growth. Surface sugar composition may thus be a proximate correlate of the evolutionarily relevant variability in infectivity and virulence of parasites in different hosts.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    facet.materialart.
    Unknown
    Elsevier
    In:  International Journal for Parasitology, 23 (6). pp. 749-755.
    Publication Date: 2018-03-23
    Description: In April 1990, 488 marine fish belonging to 30 species from central Phillipine waters were examined for flesh parasitic infections that may affect their consumability. One species of hemirhamphids and 3 species of belonids harboured plerocercoids of Otobothrium penetrans Linton, 1907 (Proceedings of the U.S. National Museum33, 85–126). This is the first record of this parasite from Pacific fish species. The highest intensity of infection found was 8 in Tylosurus crocodilus. Most of the larvae were located between the dorsal spines of the vertebral column, only 32% were found in the fillets. Based on the present material we give a description of the plerocercoid stage of the species using scanning electron microscopy of the armature and morphometrical measurements. Comparison to results from earlier findings of O. penetrons by Linton (1907; 1924, Proceedings of the U.S. National Museum64, 1–114) and to O. kurisi by Shields (1985, International Journal for Parasitology15: 635–643) lead to the conclusion that the latter species is a synonym for O. penetrans.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    facet.materialart.
    Unknown
    Elsevier
    In:  Fisheries Research, 9 (4). pp. 367-371.
    Publication Date: 2016-12-09
    Description: The growth of “Growing Sealife”™ plastic squid was tested against the principles of the von Bertalanffy growth theory. The von Bertalanffy growth curve fits the data well on visual inspection, although the Schnute curve actually provides a statistically superior fit. If the von Bertalanffy growth curve provides a reasonable fit to data, this is frequently interpreted as evidence for anabolic and catabolic changes. The results of this paper for plastic squid are intended to provide a warning that such an interpretation does not necessarily follow.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2018-03-21
    Description: Nine large box cores collected in the western Greenland-Iceland-Norwegian (GIN) Sea were analyzed for calcium carbonate content and coarse fraction components. Stratigraphic control is based on oxygen isotope records performed on four of the cores. All cores were correlated using oxygen and carbon isotope data, fluctuations in calcium carbonate content, coarse terrigenous particle content and volcanic ash beds. Glacial and interglacial cycles are documented by a number of terrigenous particle events and differentiated calcium carbonate production which can be correlated to major paleoceanographic and paleoclimatic shifts. In the older core sections, extensive deposition of ice-rafted detritus (IRD) persisted until about oxygen isotope stage 9 and document a relatively stable environment in this area, strongly influenced by cold surface water masses. The following interval was characterized by variations in the general surface water circulation pattern, although high amounts of IRD are still present in Iceland Sea sediments. Pronounced shifts in terrigenous input and pelagic carbonate records were identified close to the oxygen isotope stage Full-size image (〈1 K) and Full-size image (〈1 K) boundaries, indicating massive melting of icebergs in the western GIN Sea. These enormous inputs of debris were followed by an increase in calcium carbonate production caused by maximum intrusion of warm Atlantic surface waters. Relatively high calcium carbonate contents also show that only little dilution by fine-grained material and a minimum of ice melting occurred during these warm phases. During oxygen isotope stage 5, conditions were more uniform indicating a less pronounced westward penetration of Atlantic waters as compared to the Holocene. The last glacial (stages 4-2) is characterized by the occurrence of “Heinrich”-like events, although high IRD contents were present throughout this interval. A distinct contrast between the northernmost cores and the cores in the south is indicative of a rather strong westward penetration of Atlantic water in the north and of an area dominated by cold water east of the Kolbeinsey Ridge during the Holocene. However, conditions west of Jan Mayen seem to have remained constantly dominated by cold surface waters throughout the whole time investigated.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    facet.materialart.
    Unknown
    Elsevier
    In:  Fisheries Research, 8 (4). pp. 335-350.
    Publication Date: 2017-01-18
    Description: Methodology for assessing squid fisheries is presented focusing on the estimation of exploitation rate, stock size and the fishing power of the vessels. The assessment is designed to provide input into management decisions for effort limited fisheries. The fishery for Illex argentinus around the Falkland Islands is used as an example for the methods. The development of a management policy for this fishery is described more fully in a related paper. The methods are based on modifications to standard Leslie-Delury analysis. Various regression methods are utilized depending on the number of fleets for which detailed data are available. The statistical procedures also yield estimates of the standard errors of the estimates for evaluating the assessment advice.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    facet.materialart.
    Unknown
    Elsevier
    In:  Journal of Experimental Marine Biology and Ecology, 158 (1). pp. 105-121.
    Publication Date: 2017-01-23
    Description: Sixteen samples (588 individuals) of the Argentine shortfin squid Illex argentinus were collected by commercial vessels from Falkland and surrounding waters (42°06–51°17S) between February and May 1990 and subjected to starch gel electrophoresis. Levels of electrophoretically detectable generic variability and the extent of population differentiation were determined from allele frequencies at 25 enzyme-coding loci. Low levels of genetic variability were detected, with the overall proportion of polymorphic loci, P = 0.28, mean heterozygosities per locus, H1 = 0.011, and the average effective number of alleles, Nc = 1.23. Marked population differentiation was indicated by significant differences in allele frequency among samples, and unbalanced genotypic distributions with heterozygote deficits at most loci. Nei's mean genetic distances (D) and identities (I) ranged from 0.000 to 0.130 and 1.000 to 0.878, respectively, underlining the marked genetic divergence detected. Some evidence of microgeographic differentiation (between replicates within sites) was observed. Individuals collected from northerly limits of the sampled area (42: 06 S, 58:09 W) were most genetically distinct (I = 0.878−0.904), suggesting the existence of a hitherto unrecognised subspecies or species of Illex. Emphasis is placed on the need to delimit putative stock boundaries, and develop appropriate population models to ensure conservation of genetic resources.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    facet.materialart.
    Unknown
    Elsevier
    In:  Fisheries Research, 8 (4). pp. 303-321.
    Publication Date: 2017-01-31
    Description: The biology of exploited cephalopod stocks is reviewed. Individual growth rates are high, slowing drastically or becoming erratic at sexual maturity. Growth estimates depend on aquarium studies and population modal analysis. In some cases, ring markings in the statolith appear to be age-related, but at present there is no generally applicable method of age determination. Sexes are separate and fertilization is normally by direct mating. Rapid maturation is followed by a single spawning season and, with few exceptions, an early death. Methods for estimation of fecundity are poorly developed. Annual recruitment to the population is essential and depends critically on each year's breeding success and the survival of eggs and hatchlings. Many cephalopod species have a planktonic stage of variable duration but no specialized larval stages. Cephalopods are carnivorous animals with very high gross growth efficiency. They are also consumed in large quantities by higher trophic levels leading to suggestions that cephalopods are potentially capable of supporting significantly increased levels of exploitation. The difficulties of modelling these populations are recognized
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Publication Date: 2017-04-06
    Description: We employ a combined interpretation of Hydrosweep swath bathymetry and high resolution multi-channel seismic reflection data to investigate the development of Cap Timiris Canyon, a newly discovered submarine canyon offshore Mauritania. The dominantly V-shaped and deeply entrenched canyon exhibits many fluvial features including dendritic and meander patterns, cut-off loops and terraces, and is presently incising. Distal meander patterns, confined within a narrow fault-controlled corridor, show several stages of evolution, the latest of which is dominated by a down-system meander-loop migration. Terraces exhibit a variety of internal structures suggesting they originated through different processes including sliding/slumping, uplift-induced incision and lateral accretion. We ascribe canyon origin to an ancient river system in the adjacent presently arid Sahara Desert that breached the shelf during a Plio/Pleistocene sea level lowstand and delivered sediment directly into the slope area. Our data suggest that the initial invading unchannelised sheet of sand-rich turbidity flows initiated canyon formation by gradually mobilising along linear seafloor depressions and fault-controlled zones of weakness. We propose that the development of canyon morphology and structure was influenced by the stages of active flow of the coupling river system, and hence could act as a proxy for understanding the paleo-climatic evolution of a ‘green’ Sahara since Plio/Pleistocene times.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    facet.materialart.
    Unknown
    Elsevier
    In:  Tissue and Cell, 22 (2). pp. 191-197.
    Publication Date: 2020-05-05
    Description: The organization of the chitin-proteoglycan in Loligo vulgaris pen was examined ultrastructurally and related to the molecular order indicated by X-ray diffraction. There is a centrosymmetric striated repeat of 22 nm in the system which is based upon dark and light bands of unequal width. The banding is orientated perpendicular to the direction of the major molecular axis of the chitin fibres. The chitin molecules are laid down in sheets with a mutual, though irregular, twist to produce a laminated ‘plywood’ material.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2020-07-15
    Description: Chemical disparities at the interface between subducting oceanic crustal rocks and the harzburgitic mantle lead to the formation of reaction zones in the mantle above the subducting slabs composed of hybrid rocks that may carry exotic trace-element patterns and isotopic signatures. Subsequent burial of these metasomatised rocks as part of the progressively subducted slab could deliver trace elements and volatiles to the source region of arc magma. A natural laboratory to study reactions at the slab–mantle interface maybe found in exhumed high-pressure mélanges, where sedimentary, mafic and ultramafic lithologies are juxtaposed and metamorphosed at high-P/T conditions. A mélange zone of that type is found in northern Syros, where metasomatic reaction zones (“blackwalls”) formed on a metre scale at the contact of metasedimentary blueschists and serpentinite. Five different zones within such a contact display the assemblages (I) glaucophane+garnet+phengite+epidote, (II) glaucophane+epidote+chlorite, (III) chlorite+epidote+omphacite±albite (IV) chlorite±titanite±rutile±apatite and (V) serpentine+chromite. Accessory phases, such as apatite, allanite, rutile, titanite, tourmaline, zircon and monazite are abundant in zones II to IV. The observed succession of assemblages together with whole-rock major and trace-element compositions reflect the two dominant processes that are thought to have operated along the lithological contact: (A) diffusion of chemical components driven by the compositional contrast of the juxtaposed rocks, and (B) flux of hydrous fluids along the contact, which depleted (e.g., LILE, SiO2) or enriched (e.g., B, LREE) certain elements in various zones. Thermodynamic modelling is able to closely predict the succession of mineral assemblages as they are expected from diffusion of Mg and Ca across the contact zone. Employed to various P–T conditions and different juxtaposed rock types, this type of modelling could be used to access and evaluate larger portions of the subduction system. Our results support existing models that suggest that mixing and redistribution of major and trace elements in subduction zones may be related to the formation of hybrid rocks in mélange zones
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2017-06-27
    Description: In several fields of cell biology, correlative microscopy is applied to compare the structure of objects at high resolution under the electron microscope with low resolution light microscopy images of the same sample. It is, however, difficult to prepare samples and marker systems that are applicable for both microscopic techniques for the same specimen at the same time. In our studies, we used microbial mats from Cold Seep communities for a simple and rapid correlative microscopy method. The mats consist of bacterial and archaeal microorganisms, coupling reverse methanogenesis to the reduction of sulfate. The reverse methanogenic pathway also generates carbonates that precipitate inside the mat and may be the main reason for the formation of a microbial reef. The mat shows highly differentiated aggregates of various organisms, tightly interconnected by extracellular polysaccharides. In order to investigate the role of EPS as adhesive mucilage for the biofilm and as a precipitation matrix for carbonate minerals, samples were embedded in a hydrophilic resin (Lowicryl K4 M). Sections were suitable for light as well as electron microscopy in combination with lectins, either labeled with a fluorescent marker or with colloidal gold. This allows lectin mapping at low resolution for light microscopy in direct comparison with a highly resolved electron microscopic image.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2017-06-27
    Description: Samples collected from the shelf-edge wedge using surface grab samples and the Jago submersible constrain the KwaZulu-Natal shelf-edge wedge to a late Pliocene age on the basis of the absence of Gephyrocapsa oceanica s.l. and Discoaster brouweri, and the presence of Calcidiscus macintyrei. This correlates with proposed Tertiary sea-level curves for southern Africa and indicates relative sea-level fall during the late Pliocene coupled with hinterland uplift. Exposed failure scarps in the upper portions of submarine canyons yield sediment samples of early Pleistocene ages, indicating the uppermost age of deposition of clinoform topsets exposed in the scarp walls. Partially consolidated, interbedded silty and sandy deposits of similar age outcrop in the thalweg of Leven canyon at a depth of 150 m. These sediments provide an upper age limit of the shelf-edge wedge of early Pleistocene, giving a sedimentation rate of this wedge of 162–309 m/Ma. The distribution of widespread basal-most Pleistocene sediments on the upper slope indicates that these sediments escaped major reworking during sea-level falls associated with Pleistocene glaciations and remain as relict upper slope veneers. The absence of more recent sediments suggests that this area has been a zone of sediment bypass or starvation since the early Pleistocene. Areas where younger sediments mantle deposits of early Pleistocene ages represent areas of offshore bedload parting, re-distributing younger Holocene sediment offshore and downslope.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2018-03-09
    Description: Prompted by recent data analyses suggesting that the flux of particulate organic carbon sinking into deep waters is determined by fluxes of mineral ballasts, we undertook a study of the relationships among organic matter (OM), calcium carbonate, opal, lithogenic material, and excess aluminum fluxes as part of the MedFlux project. We measured fluxes of particulate components during Spring and Summer of 2003, and Spring of 2005, using a swimmer-excluding sediment trap design capable of measuring fluxes both in a time-series (TS) mode and in a configuration for obtaining particle settling velocity (SV) profiles. On the basis of these studies, we suggest that distinct OM–ballast associations observed in particles sinking at a depth of ∼200 m imply that the mechanistic basis of the organic matter–ballast association is set in the upper water column above the Twilight Zone, and that the importance of different ballast types follows the seasonal succession of phytoplankton. As in other studies, carbonate appears to enhance the flux of organic matter over opal. Particles must be at least half organic matter before their settling velocity is affected by ballast concentration. This lack of change in ballast composition with SV in particles with 〈40% OM content suggests that particle SV reaches a maximum because of the increasing importance of inertial drag. Relative amounts of OM and opal decrease with depth due to decomposition and dissolution; carbonates and lithogenic material contribute about the same amount to total mass, or increase slightly, throughout the water column. The high proportion of excess Al cannot be explained by its incorporation into diatom opal or reverse weathering, so Al is most likely adsorbed to particulate oxides. On shorter time scales, dust appears to increase particle flux through its role in aggregation rather than by nutrient inputs enhancing productivity. We suggest that the role of dust as a catalyst in particle formation may be a central mechanism in flux formation in this region, particularly when zooplankton fecal pellet production is low.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Publication Date: 2020-08-12
    Description: The four naturally-occurring radium isotopes (223Ra, 224Ra, 226Ra and 228Ra) were used to estimate the submarine groundwater discharge (SGD) in the Isola La Cura marsh area in the northern Venice Lagoon (Italy). By determining the radium contributors to the study area (river, coastal ocean and sediments) the radium excess in the lagoon water was quantified through a mass balance model. This radium excess is attributed to a submarine groundwater discharge source and represents the most important input of radium. Possible endmembers were considered from analysis of groundwater samples (subtidal and marsh piezometers, marsh wells and seepage meters) that were enriched in Ra by one to two orders of magnitude relative to surface waters. In particular, a permeable layer at 80 cm depth in the surrounding marsh is considered to be representative of the most likely SGD source, although similar radium activities were measured in other subtidal porewater samples collected in the Isola La Cura area. The estimated SGD flux to the study area ranged from 1 · 109 to 6 · 109 L·d− 1, the same order of magnitude as the overall riverine input to the lagoon (3 · 109 L·d− 1). A major fraction of this SGD flux is likely recirculated seawater, as evidenced by the endmember salinity. The water residence time of 2 days was estimated by both using the shortest-lived radium isotope and estimating the volume of water exchanged between the lagoon and the open sea during a tidal cycle (tidal prism approach). This SGD flux could be used to estimate the input of other chemical species (metals, nutrients, etc.) via SGD which might affect the Venice Lagoon ecosystem.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Publication Date: 2020-08-12
    Description: There is increasing evidence that submarine groundwater discharge (SGD) in many areas represents a major source of dissolved chemical constituents to the coastal ocean. In Great South Bay, NY, previous studies have shown that the discharge of nutrients with SGD may cause harmful algal blooms. This study estimates SGD to Great South Bay during August 2006 by performing a mass balance for each of the dissolved Ra isotopes (224Ra, 223Ra, 228Ra, 226Ra). The budget indicates a major unknown source (between 30 and 60% of the total input) of Ra to the bay. This imbalance can be resolved by a flux of Ra-enriched groundwater on the order of 3.5–4.5 × 109 L d− 1, depending on the Ra isotope. The Ra-estimated SGD rates compare well with those previously estimated by models of flow that decreases exponentially away from shore. Compared to previous reports of fresh groundwater discharge to the bay, the Ra-estimated discharge must comprise approximately 90% recirculated seawater. The good agreement between Ra- and model-estimated flow rates indicates that the primary SGD endmember may be best sampled at shallow depths in the sediments a short distance bayward of the low tide line.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Publication Date: 2018-03-09
    Description: Seasonal (Spring and Summer 2002) concentrations of dissolved (〈0.22 μm) trace metals (Ag, Al, Co, Cu, Mn, Ni, Pb), inorganic nutrients (NO3, PO4, Si), and DOC were determined in groundwater samples from 5 wells aligned along a 30 m shore-normal transect in West Neck Bay, Long Island, NY. Results show that significant, systematic changes in groundwater trace metal and nutrient composition occur along the flowpath from land to sea. While conservative mixing between West Neck Bay water and the groundwaters explains the behavior of Si and DOC, non-conservative inputs for Co and Ni were observed (concentration increases of 10- and 2-fold, respectively) and removal of PO4 and NO3 (decreases to about half) along the transport pathway. Groundwater-associated chemical fluxes from the aquifer to the embayment calculated for constituents not exhibiting conservative behavior can vary by orders of magnitude depending on sampling location and season (e.g. Co, 3.4 × 102– 8.2 × 103 μmol d−1). Using measured values from different wells as being representative of the true groundwater endmember chemical composition also results in calculation of very different fluxes (e.g., Cu, 6.3 × 103 μmol d−1 (inland, freshwater well) vs. 2.1 × 105 μmol d−1(seaward well, S = 17 ppt)). This study suggests that seasonal variability and chemical changes occurring within the subterranean estuary must be taken into account when determining the groundwater flux of dissolved trace metals and nutrients to the coastal ocean.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    Publication Date: 2018-03-09
    Description: A mass balance for the naturally-occurring radium isotopes (224Ra, 223Ra, 228Ra, and 226Ra) in Jamaica Bay, NY, was conducted by directly estimating the individual Ra contributions of wastewater discharge, diffusion from fine-grained subtidal sediments, water percolation through marshes, desorption from resuspended particles, and water exchange at the inlet. The mass balance revealed a major unknown source term accounting for 19–71% of the total Ra input, which could only be resolved by invoking a source from submarine groundwater. Shallow (〈 2 m depth) groundwater from permeable sediments in Jamaica Bay was brackish and enriched in Ra relative to surface bay waters by over two orders of magnitude. To balance Ra fluxes, a submarine groundwater input of 0.8 × 109–9.0 × 109 L d− 1 was required. This flux was similar for all four isotopes, with individual estimates varying by less than a factor of 2. Our calculated groundwater flux was 6- to 70-fold higher than the fresh groundwater discharge to the bay estimated by hydrological methods, but closely matched direct flow rates measured with seepage meters. This suggests that a substantial portion of the discharge consisted of recirculated seawater. The magnitude of submarine groundwater discharge varied seasonally, in the order: summer 〉 autumn 〉 spring. Chemical analyses suggest that the recirculated seawater component of submarine groundwater delivers as much dissolved nitrogen to the bay as the fresh groundwater flux.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Publication Date: 2018-03-09
    Description: Distributions of dissolved vitamin B12 and total dissolved Co were measured to gain an understanding of the cycling of these interdependent micronutrients in six marine settings including; an upwelling location, a semi-enclosed bay, two urban coastal systems, and two open ocean locations. Along the coast of Baja California, Mexico, concentrations of B12 and dissolved Co varied from 0.2 to 11 pM and 180 to 990 pM, respectively. At a nearby upwelling station, vitamin B12 and Co concentrations ranged from 0.3 to 7.0 pM and 22 to 145 pM, and concentrations did not correlate with upwelling intensity. Concentrations of B12 were highest within Todos Santos Bay, a semi-enclosed bay off the coast of Baja California, Mexico, during a dinoflagellate bloom, ranging from 2 to 61 pM, while Co concentrations varied between 61 and 194 pM. In the anthropogenically impacted Long Island Sound, NY, U.S.A., B12 levels were between 0.1 and 23 pM and Co concentrations varied from 60 to 1900 pM. However, anthropogenic inputs were not evident in B12 levels in the San Pedro Basin, located outside Los Angeles, Ca, U.S.A., where concentrations of B12 were 0.2–1.8 pM, approximating observed open ocean B12 concentrations. In the Southern Ocean and North Atlantic Ocean, B12 levels were 0.4–4 pM and 0.2–2 pM, respectively. Total Co concentrations in the Southern Ocean and North Atlantic tended to be low; measuring 26–59 pM and 15–80 pM, respectively. These low Co concentrations may limit B12 synthesis and its availability to B12-requiring phytoplankton because the total dissolved Co pool is not necessarily entirely bioavailable.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    facet.materialart.
    Unknown
    Elsevier
    In:  Tectonophysics, 173 (1-4). pp. 83-93.
    Publication Date: 2019-05-08
    Description: A deep Seismic reflection profile collected by DEKORP and BELCORP in the western Rhenish Massif was supplemented by wide-angle measurements. Signals from a vibrator source were successfully recorded to a distance of 60 km. A passive recording array was operated that recorded all shots along the profile. The wide-angle and near-vertical data were used to construct a velocity model for the profile. Most of the wide-angle reflections coincide with strong near-vertical reflections or bands of high reflectivity. The North Variscan Deformation Front, seen as a prominent shallow reflection on many profiles in this region, separates an upper crust with rather nigh velocities from a layer with lower velocities underneath. At a depth of 20–22 km a thin (2–3 km thick) layer of high velocities is found. The Moho is not reflective either in the near-vertical or in the wide-angle data, suggesting the presence of a thick crust-mantle transition zone.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    facet.materialart.
    Unknown
    Elsevier
    In:  Tectonophysics, 405 (1-4). pp. 121-140.
    Publication Date: 2019-04-29
    Description: The Hawaiian–Emperor Seamount chain records the motion of the Pacific Plate relative to the Hawaiian mantle hotspot for ~80 m.y. A notable feature of the chain is the pronounced bend at its middle. This bend had been widely credited to a change in plate motion, but recent research suggests a change in hotspot motion as an alternative. Existing paleomagnetic data from the Emperor Chain suggest that the hotspot moved south during the Late Cretaceous and Early Tertiary, but reached its current latitude by the age of the bend. Thus, data from area of the bend are important for understanding changes in plume latitude. In this study, we analyze the magnetic anomalies of five seamounts (Annei, Daikakuji-W, Daikakuji- E, Abbott, and Colahan) in the region of the bend. These particular seamounts were chosen because they have been recently surveyed to collect multibeam bathymetry and magnetic data positioned with GPS navigation. Inversions of the magnetic and bathymetric data were performed to determine the mean magnetization of each seamount and from these results, paleomagnetic poles and paleolatitudes were calculated. Three of the five seamounts have reversed magnetic polarities (two are normal) and four contain a small volume of magnetic polarity opposite to the main body, consistent with formation during the Early Cenozoic, a time of geomagnetic field reversals. Although magnetization inhomogene ties can degrade the accuracy of paleomagnetic poles calculated from such models, the seamounts give results consistent with one another and with other Pacific paleomagnetic data of approximately the same age. Seamount paleolatitudes range from 13.7 to 23.7, with an average of 19.4F7.4 (2j). These values are indistinguishable from the present-day paleolatitude of the Hawaiian hotspot. Together with other paleomagnetic and geologic evidence, these data imply that the Hawaiian hotspot has moved little in latitude during the past ~45 m.y.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    facet.materialart.
    Unknown
    Elsevier
    In:  Cretaceous Research, 29 (5-6). pp. 725-753.
    Publication Date: 2018-02-07
    Description: The Cretaceous is a special episode in the history of the Earth named for a unique rock type, chalk. Chalk is similar to modern deep-sea calcareous ooze and its deposition in epicontinental seas occurred as these areas became an integral part of the ocean. The shelf-break fronts that today separate inshore from open-ocean waters cannot have existed during the Late Cretaceous probably because the higher sea level brought the base of the wind-mixed Ekman layer above the sea floor on the continental margins. A second peculiarity of the Cretaceous is its warm equable climate. Tropical and polar temperatures were warmer than today. Meridional and ocean-continent temperature gradients were lower. The warmer climate was a reflection of higher atmospheric levels of greenhouse gasses, CO2 and possibly CH4, reinforced by higher water vapor content in response to the warmer temperatures. Most of the additional energy involved in the meridional heat transport system was transported as latent heat of vaporization of H20 by the atmosphere. Poleward heat transport may have been as much as 1 Petawatt (20%) greater than it is today. C3 plants provided for more efficient energy transport into the interior of the continents. Circulation of the Cretaceous ocean may have been very different from that of today. It is impossible for large areas of the modern ocean to become anoxic, but episodes of local anoxia occurred during the earlier Cretaceous and became regional to global during the middle of the Cretaceous. The present ocean structure depends on constant wind systems, which in turn depend on stability of the atmospheric pressure systems forced by polar ice. During most of the Cretaceous the polar regions were ice free. Without polar ice there were seasonal reversals of the high-latitude atmospheric pressure systems, resulting in disruption of the mid- and high latitude wind systems. Without constant mid-latitude westerly winds, there would be no subtropical and polar fronts in the ocean, no well-developed ocean pycnocline, and no tropical subtropical gyres dominating ocean circulation. Instead the ocean circulation would be accomplished through mesoscale eddies which could carry warmth to the polar regions. Greater knowledge and understanding of the Cretaceous is critical for learning how the climate system operates when one or both polar regions are ice free.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    facet.materialart.
    Unknown
    Elsevier
    In:  Continental Shelf Research, 11 (8-10). pp. 1155-1179.
    Publication Date: 2018-03-02
    Description: The inner Scotian Shelf off the Eastern Shore of Nova Scotia forms an irregular surface that extends some 25–30 km seaward of the present coastline to water depths of about 100 m where it drops off into Emerald Basin. The distribution of Late Quaternary deposits is highly variable both along and across the shelf. These sediments preserve a record of Late Wisconsinan glaciation, ice recession, and late- and post-glacial changes of relative sea level. Glaciomarine deposits occur in a valley complex extending seaward from Halifax Harbour. East of Halifax, we observe a three-part zonation across the inner shelf. The innermost zone extends to water depths of about 50 m. It is characterized by acoustic basement (Meguma Group metasediments), either outcropping or overlain by acoustically unstratified deposits, interpreted as glacial diamict, and by a unit interpreted as stratified outwash. These units are overlain by stratified valleyfill deposits representing Holocene lacustrine and estuarine facies, which have been sampled in a number of cores. Much of the inner shelf is covered by a thin veneer of sand and gravel, generally less than 1 m thick. Further seaward, the sea floor is an erosional unconformity that truncates acoustic units interpreted as glacial diamict and stratified drift. The stratified estuarine deposits found in the inner zone appear to be absent here, but thin patches of transgressive lag deposits occur throughout the area. The outer part of the inner shelf is dominated by outcrop of acoustic basement, with very limited surficial sediment cover. This zone of rugged outcrop occupies half or more of the inner shelf width over much of the study area. The extensive outcrop is attributed to a combination of glacial and/or glaciofluvial erosion, limited recessional deposition, and reworking of any remaining sediment cover by energetic long-period surface gravity waves under lower postglacial sea levels. Seaward of the outcrop zone, there is a transitional area between the inner shelf and Emerald Basin. This zone is characterized by high relief, with exposures of acoustic basement rising up to 60 m above intervening depressions. The depressions are partially filled by stratified glaciomarine and marine deposits up to 55 m thick. Lateral transitions between stratified and unstratified facies along a morainal ridge in northern Emerald Basin suggest the presence of a partially grounded floating ice margin in this area. Late-glacial relative sea level changes remain poorly defined. Several lines of evidence suggest high relative sea level early in the process of glacial recession from the inner shelf, followed by a rapid drop resulting from glacio-isostatic rebound. Samples of estuarine and salt-marsh deposits collected in cores from the inner part of the inner shelf provide evidence of Holocene marine transgression from below −40 m at 11,000 years BP, continuing to the present.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    facet.materialart.
    Unknown
    Elsevier
    In:  Deep Sea Research Part II: Topical Studies in Oceanography, 40 (3). pp. 783-800.
    Publication Date: 2018-03-05
    Description: Horizontal distribution of myctophid fishes were studied from two transects in the Arabian Sea in 1987. Species numbers exhibited a south-north decline in diversity, with only half of the fish taxa occupying the northeastern region. Diaphus arabicus was the dominant species both in the south and north. All recorded myctophid fish species migrate in a diel pattern, residing during daytime at depths of extremely low oxygen levels (〈0.1 ml O2 1−1) and foraging in the oxygen-rich surface layer at night. Feeding patterns were determined for the six most abundant myctophid species. All species appeared to be opportunistic predators that prey on a comparatively narrow food spectrum consisting principally of small to medium sized copepods. Numerically, non-calanoid copepods (with Oncaea conifera and O. venusta dominating) made up to 70% of the diet of D. arabicus and Bolinichthys longipes. Of the 26 calanoid copepod species identified from the six myctophid taxa, the genera Euchaeta, Pleuromamma and Candacia generally dominated in the stomachs, with P. indica constituting between 21 and 95% (by numbers) of the calanoid copepod prey.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    facet.materialart.
    Unknown
    Elsevier
    In:  Deep Sea Research Part I: Oceanographic Research Papers, 40 (6). pp. 1155-1168.
    Publication Date: 2018-03-05
    Description: Particulate fluxes of aluminium, cadmium, cobalt, copper, iron, manganese, nickel, phosphorus, lead, vanadium and zinc in the northeast subtropical Atlantic Ocean have been determined from sediment trap samples collected between 1 December 1986 and 30 April 1987 at 1020 and 4120 m below the ocean surface. The fluxes of most elements (except Cd and P) show small variations between the different layers, and are closely associated with the vertical transport of aluminium. Elemental composition and flux rates suggest that aerosol loadings from northeast trade winds are the major contributor of these elements to depositing material. Extremely low fluxes of copper, lead and zinc also indicate that anthropogenic perturbations are of insignificant importance in this region.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Publication Date: 2018-03-05
    Description: Within the framework of the JGOFS Pilot Study in 1989 mesozooplankton (0.2–20 mm) was sampled by means of a Hydro-Bios multinet in five depth strata (0–25, 25–50, 50–100, 100–200, 200–500 m) during four Lagrangian drift experiments of 8–14 days' duration at 18, 33, 46 and 58°N, to follow the seasonal progress of the phytoplankton spring bloom development in the northeast Atlantic. Mesozooplankton standing stock, measured as dry weight and ash-free dry weight, increased by a factor of about 6 from 18 to 58°N. Day/night differences amounted to 10–20% of the average and were—with one exception at 18°N—not statistically significant. Using the data on weight-specific respiration rates measured by colleagues on the same cruise, the ingestion rates and potential community grazing of mesozooplankton on phytoplankton within the upper 100 m of the water column were calculated. During all four drift experiments, quasi-steady-state conditions were observed in phyto- and zooplankton standing stock, primary production and daily sedimentation at 100 m depth. The maximum potential grazing rate by mesozooplankton accounted for about half of the daily primary production. Since sedimentation of fresh phytoplankton was negligible, it is concluded that the grazing pressure exercised by mesozooplankton together with micro- and nanozooplankton was responsible for keeping the phytoplankton standing stock at a more or less constant level during the investigated spring bloom in the four areas. Particle flux was thus dominated by zooplankton faecal material.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    facet.materialart.
    Unknown
    Elsevier
    In:  Journal of Chromatography A, 642 (1-2). pp. 425-434.
    Publication Date: 2019-02-27
    Description: Accurate congener-specific determination of chlorobiphenyl congeners (all 209 congeners) is finally possible with the use of multidimensional gas chromatography-electron-capture detection techniques. The effectiveness of this technique for environmental analyses is enhanced by ultraclean laboratory practices, non-destructive extraction and clean-up steps and the use of low-volume, high-efficiency HPLC separation for various classes of organic contaminants. In the light of these new developments conventional procedures for chlorobiphenyl analysis are evaluated.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    facet.materialart.
    Unknown
    Elsevier
    In:  Deep Sea Research Part II: Topical Studies in Oceanography, 40 (3). pp. 711-735.
    Publication Date: 2018-03-05
    Description: The productivity regime and size structure of phytoplankton are described for three different epipelagic systems in the Arabian Sea during the inter-monsoon period in spring 1987: (1) the coast of Oman; (2) the central Arabian Sea; and (3) the shelf off Pakistan. These results are related to the functioning of the specific ecosystem. Off the coast of Oman, the transition from a surface maximum of autotrophic biomass and production to a more oligotrophic system, with a chlorophyll subsurface maximum, was observed. Concomitantly, the size spectrum changed towards a higher significance of picoplankton. In the central Arabian Sea, a typical oligotrophic system with a pronounced subsurface maximum of autotrophic biomass and primary production was encountered. Here, the epipelagic system could be divided into two distinct sub-systems: the surface layer “regenerated” production, the predominance of picophytoplankton and minor losses due to sedimentation, thus a “closed” system; and the subsurface maximum layer at the nutricline characterized by higher sedimentation losses and more diatoms. Both sub-systems showed about the same productivity, the turnover in the surface layer having been much greater than in the subsurface maximum. The system on the shelf off Pakistan is seen as a decay stage of the open ocean system when water from offshore is transported onto the shelf during the onset of monsoon winds.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Publication Date: 2018-03-14
    Description: Helium (RA = 3.0 to 5.6) and carbon (δ13C from −7.2 to −3.4‰) isotopic compositions, and relative CO2, CH4, N2, He and Ar contents of CO2-rich gases from Lakes Nyos and Monoun, Cameroon; Laacher See, Germany; Dieng Volcanic Plateau, Indonesia, and a well at Mt. Gambier, Australia, point to a common, essentially magmatic origin. Absorption of the original magmatic gases into deeply circulating groundwater and equilibration of the resulting solutions with crustal rock at temperatures of about 300°C fix CO2 and CH4 contents. On further rise, the solutions start to boil separating gas-rich vapors which, on encountering an impermeable barrier, may accumulate to form gas pockets with steadily increasing pressures. In the case of sufficiently high gas contents, the pressures may exceed lithostatic pressures leading to a blow-out or a “pneumatic” eruption (Dieng). Otherwise, gas may accumulate to form a stable pocket (Mt. Gambier). Minor leakage from such pockets may lead to surface discharges of CO2-rich gases as at Laacher See, re-absorption into shallow groundwater to the formation of the low-salinity, CO2-charged waters encountered at Lakes Nyos and Monoun. The occurrence of these high-CO2, low-temperature systems is likely to be favored in tectonically active regions, allowing deep, possibly mantle gases to rise, but with sufficiently low regional heat flows to prevent the establishment of large-scale geothermal activity.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
  • 86
    Publication Date: 2018-06-15
    Description: The levels of four trace metals (Cd, Cu, Pb, and Zn) in the whole soft body and in different organs of the ocean quahog Arctica islandica were evaluated from four stations in Kiel Bay, Western Baltic. The relationships between the contents and concentrations of these metals and body size (weight and length) were also investigated. Double logarithmic plots of metal contents and concentrations against dry body weight and shell length, respectively, show straight-line relationships. The results indicate that smaller individuals have higher concentrations of Cu and Zn, two essential metals, while larger individuals have higher concentrations of Cd and Pb, two non-essential metals. The calculated regression slopes of metal content against dry-body weight revealed that Cd and Cu appear to be affected by maturation since two different slopes are observed for both metals before and after maturation. This was not obvious for Pb and Zn. Pooled slopes of metal content against dry-body weight for all animal sizes indicated that Cu and Zn have a one common slope of (0.82) and Cd and Pb another common one of (1.51). Plots of metal concentrations against shell length indicated also that Cu and Zn have one common slope of (−0.54) and Cd and Pb another one of (1.56). Moreover, it was possible to calculate one final slope of (1.53) for Cd and Pb from both content/weight and concentration/length plots. This indicates that A. islandica may have one metabolic strategy for the essential metals and another for the non-essential metals.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    facet.materialart.
    Unknown
    Elsevier
    In:  Brain Research, 519 (1-2). pp. 315-323.
    Publication Date: 2020-06-23
    Description: Brain pathways controlling the chromatophores of the squidLolliguncula brevis are described using cobalt iontophoresis. The results show several input and output pathways of the anterior and posterior chromatophore and lateral basal lobes. These connections allow coordination and modification of the chromatophore motor program throughout the motor pathway. Unlike other cephalopod species, there seems to be no direct input from the optic lobes to the lateral basal lobes inL. brevis. This species displays only a few simple patterns; therefore the underlying neural pathways for chromatophore control may be different from those of other cephalopods with more extensive patterning repertoires.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Publication Date: 2017-06-23
    Description: Coccolith and dinoflagellate cyst assemblages have been investigated in five sediment cores from the Norwegian Sea and Fram Strait. Both fossil groups are characterized by similar patterns of composition. The assemblages contain high proportions of single species. The coccolith flora is of low diversity and consists almost entirely of Coccolithus pelagicus and Emiliania huxleyi. The dinoflagellate cysts are generally dominated by Operculodinium centrocarpum and Nematosphaeropsis labyrinthus. Other species, especially Bitectatodinium tepikiense, Peridinium faeroense and Impagidinium pallidum, sometimes contribute considerably to the assemblages. Based on the abundance of the assemblages and the ratio change between the dominating species it has been possible to establish three intervals of distinct major changes in surface water mass conditions. Sparse occurrences of coccoliths and dinoflagellate cysts have been observed before 10,000 yrs. B.P., indicating harsh environmental conditions with a distinct influence of meltwater and temporarily very slight inflow of Atlantic water. The modern surface-water circulation pattern was reinitiated during Termination IB. The assemblages suggest slightly cooler and probably less saline surface water conditions than are present today until 7500 yrs B.P. Solar insolation may have caused a first temperature peak which is responsible for the early Holocene productivity maximum. A considerable change in the composition of dinocyst and coccolith assemblages occurs corresponding approximately to the onset of the Holocene climatic optimum. This change was most probably linked to an almost synchronous reorganization of the hydrographic properties in the entire North Atlantic realm after the ice sheets had vanished. Since 6000 yrs B.P. the Norwegian Current with its modern oceanographic and ecological properties has been fully established.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    facet.materialart.
    Unknown
    Elsevier
    In:  Animal Behaviour, 28 (4). pp. 1123-1126.
    Publication Date: 2017-02-01
    Description: Pairs of individually recognizable male Octopus vulgaris were observed in a large seawater tank containing two suitable homes (brick pots or plastic buckets). None of the animals established exclusive occupancy of one home and for much of the time both animals were associated together at the same site. Usually one of the two homes was preferred and its occupant was most likely to be the larger animal, or the earlier resident if they were of equal size. Large animals were observed to take food forcefully from smaller octopus. An arm alignment interaction is described which, it is suggested, may be a means by which two octopuses establish their relative sizes.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2020-07-30
    Description: The South Aegean Active Volcanic Arc consists of a chain of five volcanic centers, the most active of which is the Santorini Volcano. A local radio-linked seismological network is installed on the island consisting of five permanent and four temporary stations. The temporary stations have been in operation periodically during the period 1994–1996 and two of them were installed on adjacent islands. All stations are equipped with vertical-component short period seismometers. During the period 1994–2002 a significant number of earthquakes has been recorded, with local (duration) magnitudes, MD, up to 5.0 and focal depths varying between 0 km and 35 km. Two clusters of epicenters have been located in the broader area of the Santorini Volcano. The first cluster is located in the caldera of the volcano and is associated with the volcanic process in the Kameni Island. The second (larger) cluster is located near the northern edge of the Santorini Island at the Kolumbo Reef and is connected with the volcanic process at this reef. These clusters can be appropriately associated with the two main tectonic features (faults) in the area under study. The first one (N60°E direction) corresponds to the continuation of the Amorgos fault in the area, while the secondary tectonic line (EW direction) is probably related with the southern edge of a submarine graben, which is located between the islands Amorgos and Santorini. Using the data set of the best-located earthquakes, recorded during the period 1994–2002, an attempt has been made to derive an appropriate equivalent 1 –D earth model for the area under study, in order to improve the accuracy of the determined hypocenters, as well as to obtain a preliminary knowledge of the volcano structure.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    facet.materialart.
    Unknown
    Elsevier
    In:  Aquaculture, 128 (1-2). pp. 143-152.
    Publication Date: 2017-05-11
    Description: A simple method of providing a regular supply of live food for the experimental culture of paralarval cephalopods is described. The primary food source utilized was hatched zoeae of large laboratory populations of the hermit crab, Pagurus prideaux. Zoeal size, swimming behaviour, and distribution in the water column make these zoeae a suitable live prey for rearing early post-hatching planktonic stages of cephalopods and probably other marine zooplanktivores. Ovigerous P. prideaux females were collected from the sea throughout the year at depths between 10 and 90 m in the NW Mediterranean and maintained at densities of up to 500 specimens · m−2. One month after spawning in aquaria, 38% of the females of P. prideaux started to incubate a second clutch of eggs. Other decapod crustacean species, such as Liocarcinus depurator and Dardanus arrosor, were maintained to use their zoeae as a food source for cephalopod paralarvae. P. prideaux zoeae were used as the sole or main food resource for rearing Loligo vulgaris and Octopus vulgaris, during the first 2 months of life. First feeding and initial growth in L. vulgaris and O. vulgaris paralarvae can be successfully stimulated using decapod zoeae with a total length equivalent to 50–100% of the cephalopod's mantle length.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Publication Date: 2017-07-10
    Description: A total of 131 current meter records of between 6 and 24 month duration are analysed to describe the deep flow field of the eastern North Atlantic from 19° to 54°N and from the Continental Slope to the Mid Atlantic Ridge. Mean flows are weak and may be statistically indeterminate in some records and locations, but appear to indicate cyclonic circulations around the Iberia and Porcupine abyssal plains with a generally southward flow along the Mid Atlantic ridge and a deep northward slope current (where measurements exist) along the eastern boundary. The deepest inflow to the north-eastern basin that has been identified to date takes place through the Discovery Gap of 〉4,700 m sill-depth at 37° 25′N 15° 45′W in the Azores-Portugal ridge. South of that ridge, observations are sparse and no systematic circulation is yet evident. These observations are discussed in relation to recent geostrophic estimates of the deep circulation.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Publication Date: 2018-03-02
    Description: Sediments on high Arctic shelves result from modern processes and the effect of former glaciations. Based on data from the northern Barents Sea, an area with input from large and numerous surging glaciers, we define two principal zones with different environmental regimes and corresponding sedimentary facies: (1) a glacier-proximal zone influenced by grounding-line processes and the immediately adjacent areas affected by glacial sediment input, and (2) a glacier-distal, sea-ice and current-controlled zone, which also includes a wide sediment-starved region dominated by biogenic carbonate accumulation. Characteristic of the glacier-proximal zone are glacial surges which affect sedimentation rates and leave a diagnostic pattern of sea-floor morphologies. Extensive ice gouging causes a homogeneous sediment texture. In the glacier-distal zone, fine-grained mud supplied from sea ice and infrequent coarser material deposited from icebergs is reworked by modern oceanographic processes. On shallow banks, in 30–50 m of water, carbonates accumulate from a prolific bottom fauna formed in response to extensive reworking and nutrient supply.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Publication Date: 2018-03-07
    Description: In February 1988, 60 near surface samples were taken on a track between 2°W in the English Channel, the Pentland Firth and the inner German Bight. Determinations were made on filtered and unfiltered samples. Concentrations of dissolved metals in the North Sea normalized to a salinity of 34.5 were Al 31, Cd 0.13, Co 0.13, Cu 3.4, Mn 6.2 and Ni 3.9 nM. In July 1984 the equivalent concentrations were Al 11, Cd 0.15, Co 0.15, Cu 4.3, Mn 12 and Ni 3.6 nM. Distinct regional differences were detectable which can be related to the origin of the water, differing river inputs, and solution-solid phase exchange reactions. The degree of the influence of exchange reactions was investigated through the concept of Kd, the distribution coefficient. A Kd of 105 ml g−1 for Al is consistent with other observations and explains the relatively high concentrations of dissolved Al detected in the English Channel on this cruise. The data suggest a higher Kd for Mn approaching 106 ml g−1. The high Mn Kd coupled to higher suspended sediment loads in winter may be sufficient to explain the lower concentration of dissolved Mn in winter. Comparison of concentrations across the shelf break suggests that for all the metals studied, the European Shelf is a source of dissolved metals to the deep sea. Calculations based on the limited available data indicate that this export is of similar magnitude to the fresh water input of dissolved metals.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    facet.materialart.
    Unknown
    Elsevier
    In:  Deep Sea Research Part II: Topical Studies in Oceanography, 40 (1-2). pp. 91-114.
    Publication Date: 2018-03-05
    Description: An overview is given of the multinational investigations carried out at 47°N 20°W for the period 24 April–31 May, with the main emphasis on the succession of plankton communities and the flux of organic carbon through various plankton components. The depth of the upper mixed layer decreased rapidly after 25 April, triggering the start of the spring bloom that developed within a 2-week period. Chlorophyll a stocks integrated to 80 m water depth reached peak concentrations during the first 10 days in May. The observed decline was partly due to the seasonal development, but also may have been influenced by changes in water masses associated with a cyclonic eddy. Primary production ranged from 50 to 150 mmol C m−2 day−1 with highest values in the first half of May. After the first bloom phase, dominated by diatoms, nanophytoplankton gained more importance as primary producers when silicate was depleted. Stocks of bacteria, microzooplankton and mesozooplankton increased in the second half of May. Bacterial production averaged 30% of primary production and probably metabolized a large amount of dissolved organic carbon (DOC) per day, but due to uncertain carbon conversion efficiencies total bacterial carbon consumption is difficult to estimate. Largely daily changes in the DOC standing stock could not be reconciled with the measured primmary production and are probably an expression of spatial rather than temporal variations. Microzooplankton was found to consume around 64% of primary production in the second half of May. Grazing estimates for mesozooplankton varied but seem to be small (〈5% of primary production) for most of the investigation period. The small mesozooplankton size classes (〈1 mm) dominated biomass and grazing. Vertical particulate organnic carbon (POC) flux measured by sediment traps in 150 m depth was around 9.8 mmol C m−2 day−1 representing approximately 11% of primary production. The spring bloom pulse of particle flux reached the deep ocean and benthos 4–6 weeks after the surface water peak.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Publication Date: 2018-03-22
    Description: Altimetric data from Geosat and some critical hydrographic measurements were used to estimate in real time the mesoscale physical oceanographic environment surrounding the Joint Global Ocean Flux Study (JGOFS) 1989 North Atlantic Bloom Experiment. Three cyclonic eddies, including an exceptionally large one, evolved and interacted over the 10 weeks of observations. Subsequent analysis of all available hydrographic data confirmed the real time estimates and provided further quantitative information concerning the mesoscale and submesoscale structure of the upper ocean. Remotely sensed indicators of near-surface chlorophyll content reveal significant biological variability on these wavelengths. The altimetric and hydrographic data have been assimilated into a dynamical model to produce optimal estimates of physical fields of interest as they evolve in time for use in physical and biological process studies
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    facet.materialart.
    Unknown
    Elsevier
    In:  Marine Pollution Bulletin, 28 (7). pp. 413-416.
    Publication Date: 2018-04-09
    Description: As long as salinity in the Baltic Sea was high (as it was between 1948 and 1982) the depth range between 70 and 100 m suffered frequent anoxia. However, when salinity was low and when the position of the halocline was deep (as it was in the first half of the century) oxygen conditions were good and long-lived macrofauna occurred. Should the present trend to lower salinities continue (building bridges across the Belt Sea and reducing salt water inflow would be helpful) one can foresee a recolonization by macrofauna in the depth range 70–100 m.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Publication Date: 2018-03-22
    Description: The influence of increasing amounts of surfactants on the toxicity of hydrocarbons was determined using the bioluminescence inhibition test (Microtox test). Three biogenic and three synthetic surfactants were tested against the water-soluble fractions (WSF) of crude and weathered Ekofisk oil, phenol, and naphthalene. Surfactant concentrations below 100 mg litre−1 lowered the toxicity of the WSF, indicating an antagonistic interaction reducing the toxicities of surfactants and hydrocarbons. At concentrations greater than 100 mg litre−1 the toxicity rose again and was higher than the untreated WSF. The point of reversal seemed to be the critical micelle concentration, at which the formation of oil/water emulsions is possible.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    facet.materialart.
    Unknown
    Elsevier
    In:  Journal of Experimental Marine Biology and Ecology, 183 (1). pp. 41-52.
    Publication Date: 2019-09-23
    Description: The reproductive cycle of the sponge Halichondria panicea was investigated at Boknis Eck in the Western Kiel Bight over 2 yr, and over 1 yr on the island Helgoland in the North Sea and was compared with material collected earlier at Tjärnö at the Swedish west coast. Temperature and salinity were monitored at the different stations in order to determine whether different hydrographic conditions could be linked to differences in seasonal patterns of the reproductive cycle. The results showed H. panicea to be gonochoristic at all stations. The ratio of males to females varied between populations and years, but females predominated consistently. Comparison of the reproductive cycle in the years 1987 and 1989 at the brackish-water station Boknis Eck shows that high ambient winter and spring temperatures in 1989 resulted in a shorter period of oogenesis and earlier larval release, as compared to the year 1987. The reproductive cycle of the sponges at the fully marine station at Helgoland in 1989 and the brackish-water station at Tjärnö in 1978 under temperature and salinity conditions similar to those at Boknis Eck in 1989 showed the same seasonal pattern. We conclude that the lower salinities found at both Boknis Eck and Tjärnö do not cause a delay or slow-down of reproduction at these stations as compared to Helgoland. Under favourable temperature conditions, oogenesis was highly synchronous within the different populations, while it was more spread over time under the low ambient water temperatures at Boknis Eck in 1987.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    facet.materialart.
    Unknown
    Elsevier
    In:  Journal of Colloid and Interface Science, 76 (2). pp. 541-556.
    Publication Date: 2016-11-30
    Description: A general method for simulating aerosol size distribution dynamics is developed. The method, based on dividing the particle size domain into sections and dealing only with one integral quantity in each section (e.g., number, surface area, or volume), has the advantages that the integral quantity is conserved within the computational domain and coagulations between all particle sizes are properly accounted for. To demonstrate the simplicity and accuracy of the method for a practical problem, the evolution of a power plant plume aerosol undergoing coagulation is simulated.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...