GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    facet.materialart.
    Unbekannt
    Population dynamics and life strategies of Rhincalanus nasutus (Copepoda) at the onset of the spring bloom in the Gulf of Aqaba (Red Sea) (2008)
    Oxford Univ. Press
    In:  Journal of Plankton Research, 30 . pp. 655-672.
    Details
    Publikationsdatum: 2018-06-05
    Beschreibung: Abundance, distribution, population structure, lipid content, lipid composition and reproductive and feeding activity of Rhincalanus nasutus were studied in the Gulf of Aqaba and in the northern Red Sea during RV “Meteor”-cruise M 44-2 in February/March 1999. Rhincalanus nasutus occurred in higher numbers in the Gulf of Aqaba (585 ind m−2) than in the northern Red Sea (254 ind m−2). Young developmental stages (nauplii, copepodite stages CI and CII) were absent. In the southern Gulf of Aqaba, the bulk of the population developed from stage CV to adult in the course of the 3-week study period. In contrast, immature CV stages dominated at the adjacent stations in the northern Gulf of Aqaba and in the northern Red Sea. Development was associated with the seasonal vertical migration from wintering mid-water layers and initiation of feeding starting as early as beginning of March in the southern Gulf of Aqaba. No upward migration was observed in the northern parts of the Gulf and in the northern Red Sea, where more than 90% of the females remained immature during our study. Lipids were dominated by wax esters in females and CV. The fatty acid and fatty alcohol compositions of females were very similar throughout the study region and period. Major fatty acids were 18:1(n−9), 16:1(n−7), 16:2(n−4) and 20:5(n−3). Our results support the previous reports of a seasonal dormancy of R. nasutus in the Gulf of Aqaba and suggest that the timing of vertical migration, feeding and maturation is closely coupled to the development of the spring bloom in oligotrophic subtropical waters.
    Materialart: Article , PeerReviewed
    Format: text
    DOI: 10.1093/plankt/fbn029
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    OceanRep: Artikel in einer Fachzeitschrift - begutachtet
  • 2
    facet.materialart.
    Unbekannt
    Microcopepod community structure in the Gulf of Aqaba and the northern Red Sea, with special reference to Oncaeidae (2008)
    Oxford Univ. Press
    In:  Journal of Plankton Research, 30 . pp. 529-550.
    Details
    Publikationsdatum: 2018-06-05
    Beschreibung: The abundance and vertical distribution of microcopepods sampled by nets with 55 μm mesh size was compared for two neighbouring but hydrographically different areas, the Gulf of Aqaba and the northernmost Red Sea, during spring 1999. The vertical structure of the total microcopepod communities differed considerably between the two regimes: In the stratified waters of the Red Sea, calanoids outnumbered oncaeids as well as oithonids at 0–100 m, whereas oncaeids dominated in all meso- and bathypelagic layers below 100 m deep. In the unusually deep vertically mixed waters of the Gulf of Aqaba, calanoids outnumbered each of the non-calanoid taxa as deep as 250 or 350 m, whereas the oncaeid dominated deep water community was restricted to depth ranges below 400 m. Dominant non-calanoid species in both areas were Oncaea bispinosa, Paroithona pacifica, Oithona simplex, Spinoncaea ivlevi, O. tregoubovi and O. cristata. O. scottodicarloi occurred in exceptionally high numbers in the northern Gulf. Pronounced differences between the two areas were found in the vertical distribution of poecilostomatoid species. By comparing the present results with published data from the central and southern Red Sea and other tropical and warm-temperate oceanic areas, intra- and inter-oceanic differences in the structure of microcopepod communities in oligotrophic areas are discussed. The high abundance and vertically extended range of calanoid copepods during spring appears to be a specific feature of the Gulf of Aqaba, indicating an unusual vertical succession in the trophodynamic structure of the copepod fauna in this area.
    Materialart: Article , PeerReviewed
    Format: text
    DOI: 10.1093/plankt/fbn018
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    OceanRep: Artikel in einer Fachzeitschrift - begutachtet
  • 3
    facet.materialart.
    Unbekannt
    Seasonal lipid dynamics of the shrimps Crangon crangon and Pandalus montagui in the German Bight (North Sea) (2019)
    INTER-RESEARCH
    In:  EPIC3Marine Ecology-Progress Series, INTER-RESEARCH, 625, pp. 41-52, ISSN: 0171-8630
    Details
    Publikationsdatum: 2019-10-09
    Beschreibung: Environmental fluctuations can impose energetic constraints on organisms in terms of food shortage or compensation for metabolic stress. To better understand the biochemical strategies that support adaptive physiological processes in variable environments, we studied the lipid dynamics of the brown shrimp Crangon crangon and the pink shrimp Pandalus montagui by analysing their midgut glands during an annual cycle. Both species have an overlapping distribu- tion range in the southern North Sea, but differ in their habitat preferences, reproductive strate- gies, and life-history traits. C. crangon showed minor total lipid accumulation in their midgut glands, ranging between 14 and 17% of dry mass (DM), dominated by phospholipids. In contrast, P. montagui stored significantly larger amounts of total lipid (47−70% DM, mainly triacylglycer- ols) and showed a distinct seasonal cycle in lipid accumulation with a maximum in summer. Fatty acid trophic markers indicated a wide food spectrum for both species, with higher preferences of P. montagui for microalgae. In C. crangon, feeding preferences were less distinct due the low total lipid levels in the midgut gland. PCA based on fatty acid compositions of both species suggested that C. crangon has a broader dietary spectrum than P. montagui. C. crangon seems to have the capacity to use sufficient energy directly from ingested food to fuel all metabolic requirements, including multiple spawnings, without building up large lipid reserves in the midgut gland. P. montagui, in contrast, relies more on the energy storage function of the midgut gland to over- come food scarcity and to allocate lipids for reproduction.
    Repository-Name: EPIC Alfred Wegener Institut
    Materialart: Article , isiRev , info:eu-repo/semantics/article
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    ARTIKEL (OA)
  • 4
    facet.materialart.
    Unbekannt
    Shell disease does not affect biochemical profiles of the North Sea brown shrimp Crangon crangon (2020)
    INTER-RESEARCH
    In:  EPIC3Diseases of Aquatic Organisms, INTER-RESEARCH, 141, ISSN: 0177-5103
    Details
    Publikationsdatum: 2020-11-12
    Beschreibung: The brown shrimp Crangon crangon is a key component of the North Atlantic coastal food web and an important target species for the fishery economy. As the brown shrimp contains large amounts of protein and essential fatty acids, its consumption makes it a beneficial choice for humans. Commercially harvested crustaceans like C. crangon are frequently affected by bacterial shell disease, with necrotizing erosions and ulcerations of the cuticle. To determine whether shell disease influences the nutritional value of C. crangon, total protein and lipid contents, as well as fatty acid compositions of muscle tissue and hepatopancreas, together with the hepatosomatic index, were examined in healthy and affected individuals. The biochemical composition of the tissues did not differ significantly between the 2 groups. Also, the hepatosomatic index, as an indicator of energy reserves in shrimps, was similar between healthy and affected animals. Our results indicate that the nutritional value of C. crangon is not affected by shell disease, as long as it remains superficial as in the present study.
    Repository-Name: EPIC Alfred Wegener Institut
    Materialart: Article , isiRev
    Format: application/pdf
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    ARTIKEL (OA)
  • 5
    facet.materialart.
    Unbekannt
    Seasonal lipid storage and dietary preferences of native European versus invasive Asian shore crabs (2018)
    INTER-RESEARCH
    In:  EPIC3Marine Ecology-Progress Series, INTER-RESEARCH, 602, pp. 169-181, ISSN: 0171-8630
    Details
    Publikationsdatum: 2018-08-24
    Beschreibung: The invasive Asian shore crab Hemigrapsus sanguineus and the native European green crab Carcinus maenas share intertidal habitats along European North Atlantic shores and may compete for food. We evaluated the energy-storing capacities of the 2 species and determined their dietary preferences by means of lipid analysis and fatty acid trophic marker indices. Specimens of both sexes and various sizes were sampled in the rocky intertidal of the island of Helgoland (North Sea) in April, June, August, and October 2015. Total lipids of the midgut glands were significantly higher in H. sanguineus than in C. maenas and followed a distinct seasonal cycle in both sexes (ca. 20−50% of dry mass, DM). The lower lipid contents of C. maenas (ca. 20% of DM) remained at a similar level throughout the seasons. The seasonal differences in the females of H. sanguineus may be due to higher reproductive output and, consequently, lipid turnover, but remain unexplained in males. Trophic indices for Bacillariophyceae, Chlorophyta, and especially Phaeophyceae were higher in H. sanguineus than in C. maenas, suggesting a higher degree of herbivory of the invader. In contrast, the Rhodophyta index was higher in C. maenas. Thus, competition for food between the 2 species will probably be low in habitats rich in macroalgae. The ability of H. sanguineus to utilize mainly energy-poor algae but accumulate high-energy reserves may be an advantage for successfully establishing persistent populations in new habitats.
    Repository-Name: EPIC Alfred Wegener Institut
    Materialart: Article , isiRev
    Format: application/pdf
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    ARTIKEL (OA)
  • 6
    facet.materialart.
    Unbekannt
    The Role of Zooplankton Grazing and Nutrient Recycling for Global Ocean Biogeochemistry and Phytoplankton Phenology (2022)
    American Geophysical Union (AGU)
    In:  EPIC3Journal of Geophysical Research Biogeosciences, American Geophysical Union (AGU), 127(10), ISSN: 2169-8953
    Details
    Publikationsdatum: 2023-06-21
    Beschreibung: Zooplankton plays a notable role in ocean biogeochemical cycles. However, it is often simulated as one generic group and top closure term in ocean biogeochemical models. This study presents the description of three zooplankton functional types (zPFTs, micro-, meso- and macrozooplankton) in the ocean biogeochemical model FESOM-REcoM. In the presented model, microzooplankton is a fast-growing herbivore group, mesozooplankton is another major consumer of phytoplankton, and macrozooplankton is a slow-growing group with a low temperature optimum. Meso- and macrozooplankton produce fast-sinking fecal pellets. With three zPFTs, the annual mean zooplankton biomass increases threefold to 210 Tg C. The new food web structure leads to a 25% increase in net primary production and a 10% decrease in export production globally. Consequently, the export ratio decreases from 17% to 12% in the model. The description of three zPFTs reduces model mismatches with observed dissolved inorganic nitrogen and chlorophyll concentrations in the South Pacific and the Arctic Ocean, respectively. Representation of three zPFTs also strongly affects phytoplankton phenology: Fast nutrient recycling by zooplankton sustains higher chlorophyll concentrations in summer and autumn. Additional zooplankton grazing delays the start of the phytoplankton bloom by 3 weeks and controls the magnitude of the bloom peak in the Southern Ocean. As a result, the system switches from a light-controlled Sverdrup system to a dilution-controlled Behrenfeld system. Overall, the results suggest that representation of multiple zPFTs is important to capture underlying processes that may shape the response of ecosystems and ecosystem services to on-going and future environmental change in model projections.
    Repository-Name: EPIC Alfred Wegener Institut
    Materialart: Article , peerRev
    Format: application/pdf
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    ARTIKEL (OA)
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...