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
Filter
Publikationsart
Schlagwörter
Verlag/Herausgeber
Sprache
Erscheinungszeitraum
  • 11
    Digitale Medien
    Digitale Medien
    Laboratory experiments on the impact of biofilms on the plankton of a large river (2003)
    Oxford, UK : Blackwell Science Ltd
    Freshwater biology 48 (2003), S. 0 
    Details
    ISSN: 1365-2427
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: 1. Benthic organisms can have a strong effect on the plankton in rivers, although normally only members of the macrofauna are considered as important consumers. In the present study we conducted experiments on four different dates (in December, March, June and September) to assess the potential role of periphytic heterotrophic flagellates (HF), ciliates and rotifers in the control of potamoplankton (bacteria, algae, HF and ciliates).2. Natural periphyton was established on the walls of circular flow channels by exposing them to river water (River Rhine, Germany). The experimental channels (with periphyton) and control channels (without periphyton) were filled with riverine water and the increase rates of planktonic bacteria, algae, HF and oligotrich ciliates were determined for the two treatments.3. The abundance of periphytic ciliates and rotifers at the beginning of the four experiments showed large differences with low values in December and March, and high values in June and September. Dominant potential consumers of plankton were the heterotrich ciliate Stentor sp. and bdelloid rotifers.4. The rates of increase of planktonic algae, HF and ciliates were significantly smaller in the presence of periphyton compared with those in their absence. Significant interactions between the treatment (with and without periphyton) and the time of experiment were found for the planktonic HF and algae, indicating that the impact of the periphyton varied temporarily. The planktonic groups responded differently to the periphyton with the planktonic HF showing the highest loss rate. Significant differences were also found among the loss rates of different HF groups and different diatom size classes.5. These laboratory experiments demonstrate that periphytic ciliates and rotifers are potentially important consumers of different planktonic groups. The quantitative impact of periphyton on plankton with respect to the selective feeding needs further attention.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1046/j.1365-2427.2003.01144.x
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 12
    Digitale Medien
    Digitale Medien
    Experimental demonstration of chaos in a microbial food web (2005)
    [s.l.] : Macmillian Magazines Ltd.
    Nature 435 (2005), S. 1226-1229 
    Details
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Discovering why natural population densities change over time and vary with location is a central goal of ecological and evolutional disciplines. The recognition that even simple ecological systems can undergo chaotic behaviour has made chaos a topic of considerable interest among theoretical ...
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1038/nature03627
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 13
    Digitale Medien
    Digitale Medien
    Rotifers as predators on components of the microbial web (bacteria, heterotrophic flagellates, ciliates) — a review (1993)
    Springer
    Hydrobiologia 255-256 (1993), S. 231-246 
    Details
    ISSN: 1573-5117
    Schlagwort(e): rotifers ; feeding ; bacteria ; ciliates ; heterotrophic flagellates ; microbial web
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Recent investigations have shown that processes within the planktonic microbial web are of great significance for the functioning of limnetic ecosystems. However, the general importance of protozoans and bacteria as food sources for rotifers, a major component of planktonic habitats, has seldom been evaluated. Results of feeding experiments and the analysis of the food size spectrum of rotifers suggest that larger bacteria, heterotrophic flagellates and small ciliates should be a common part of the food of most rotifer species. About 10–40 per cent of rotifers' food can consist of heterotrophic organisms of the microbial web. Field experiments have indicated that rotifer grazing should generally play a minor role in bacteria consumption compared to feeding by coexisting protozoans. However, according to recent experiments regarding food selection, rotifers should be efficient predators on protozoans. Laboratory experiments have revealed that even nanophagous rotifers can feed on ciliates. Preliminary microcosm and chemostat experiments have indicated that rotifers, due to their relatively low community grazing rates compared to the growth rates of bacteria and protozoans, should generally not be able (in contrast to some cladocerans) to suppress the microbial web via grazing, though they may structure it. Filter-feeding nanophagous rotifers (e.g. brachionids) seem to be significant feeders on the smaller organisms of the microbial web (bacteria, flagellates, small ciliates), whereas grasping species (e.g. synchaetids and asplanchnids) seem to be efficient predators on larger organisms (esp. ciliates). Another important role of rotifers is their feedback effect on the microbial web. Rotifers provide degraded algae, bacteria and protozoans to the microbial web and may promote microbial activity. Additional experimental work is necessary for a better understanding of the function of rotifers in aquatic ecosystems.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00025844
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 14
    facet.materialart.
    Unbekannt
    Potential contribution of surface-dwelling Sargassum algae to deep-sea ecosystems in the southern North Atlantic (2018)
    Elsevier
    In:  Deep Sea Research Part II: Topical Studies in Oceanography, 148 . pp. 21-34.
    Details
    Publikationsdatum: 2021-02-08
    Beschreibung: Deep-sea ecosystems, limited by their inability to use primary production as a source of carbon, rely on other sources to maintain life. Sedimentation of organic carbon into the deep sea has been previously studied, however, the high biomass of sedimented Sargassum algae discovered during the VEMA Transit expedition in 2014/2015 to the southern North Atlantic, and its potential as a regular carbon input, has been an underestimated phenomenon. To determine the potential for this carbon flux, a literature survey of previous studies that estimated the abundance of surface water Sargassum was conducted. We compared these estimates with quantitative analyses of sedimented Sargassum appearing on photos taken with an autonomous underwater vehicle (AUV) directly above the abyssal sediment during the expedition. Organismal communities associated to Sargassum fluitans from surface waters were investigated and Sargassum samples collected from surface waters and the deep sea were biochemically analyzed (fatty acids, stable isotopes, C:N ratios) to determine degradation potential and the trophic significance within deep-sea communities. The estimated Sargassum biomass (fresh weight) in the deep sea (0.07 − 3.75 g/m2) was several times higher than that estimated from surface waters in the North Atlantic (0.024 – 0.84 g/m2). Biochemical analysis showed degradation of Sargassum occurring during sedimentation or in the deep sea, however, fatty acid and stable isotope analysis did not indicate direct trophic interactions between the algae and benthic organisms. Thus, it is assumed that components of the deep-sea microbial food web form an important link between the macroalgae and larger benthic organisms. Evaluation of the epifauna showed a diverse nano- micro-, meio, and macrofauna on surface Sargassum and maybe transported across the Atlantic, but we had no evidence for a vertical exchange of fauna components. The large-scale sedimentation of Sargassum forms an important trophic link between surface and benthic production and has to be further considered in the future as a regular carbon input to the deep-sea floor in the North Atlantic.
    Materialart: Article , PeerReviewed
    Format: text
    Format: text
    DOI: 10.1016/j.dsr2.2017.10.002
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    OceanRep: Artikel in einer Fachzeitschrift - begutachtet
  • 15
    facet.materialart.
    Unbekannt
    Vertical distribution of epibenthic megafauna of a large seamount west of Cape Verde islands (tropical North Atlantic) (2024)
    Springer
    Details
    Publikationsdatum: 2024-02-05
    Beschreibung: Seamounts are thought to function as hotspots of megafauna diversity due to their topology and environmental characteristics. However, assessments of megafauna communities inhabiting seamounts, including diversity and density, are scarce. In this study, we provide megafauna diversity and density estimates for a recently discovered, not yet characterized seamount region (Boetius seamounts) west of Cape Verde (N17° 16′, W29° 26′). We investigated the distribution of epibenthic megafauna over a large depth gradient from the seamount’s summit at 1400 m down to 3200 m water depth and provided qualitative and quantitative analyses based on quantified video data. In utilizing an ocean floor observation system (OFOS), calibrated videos were taken as a horizontal transect from the north-eastern flank of the seamount, differentiating between an upper, coral-rich region (−1354/−2358 m) and a deeper, sponge-rich region (−2358/−3218 m). Taxa were morphologically distinguished, and their diversity and densities were estimated and related to substrate types. Both the upper and deeper seamount region hosted unique communities with significantly higher megafauna richness at the seamount’s summit. Megafauna densities differed significantly between the upper (0.297 ± 0.167 Ind./m 2 ) and deeper community (0.112 ± 0.114 Ind./m). The seamount showed a vertical zonation with dense aggregations of deep-sea corals dominating the seamount’s upper region and colonies of the glass sponges Poliopogon amadou dominating the deeper region. The results are discussed in light of detected substrate preferences and co-occurrence of species and are compared with findings from other Atlantic seamounts.
    Materialart: Article , PeerReviewed
    Format: text
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    OceanRep: Artikel in einer Fachzeitschrift - begutachtet
  • 16
    facet.materialart.
    Unbekannt
    Maximum ingestion and maximum clearance rate of Nanoflagellates determined experimentally (2014)
    PANGAEA
    Details
    Publikationsdatum: 2024-01-26
    Schlagwort(e): Biomass as carbon per individual; Clearance rate per individual; EXP; Experiment; Nanoflagellates_FEEDEXP; Taxon/taxa; Treatment: temperature; Uniform resource locator/link to reference
    Materialart: Dataset
    Format: text/tab-separated-values, 15 data points
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    DATA PANGAEA
  • 17
    facet.materialart.
    Unbekannt
    Raw multibeam EM122 data: transits of METEOR cruise M139 (Tropical Atlantic) (2017)
    PANGAEA
    Details
    Publikationsdatum: 2024-02-27
    Schlagwort(e): AtlantOS; Bathymetry; CT; DATE/TIME; File format; File name; File size; LATITUDE; LONGITUDE; M139; M139-track; Meteor (1986); Optimizing and Enhancing the Integrated Atlantic Ocean Observing System; Swath-mapping system Simrad EM122 (Kongsberg Maritime AS); Underway cruise track measurements; Uniform resource locator/link to raw data file
    Materialart: Dataset
    Format: text/tab-separated-values, 2608 data points
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    DATA PANGAEA
  • 18
    facet.materialart.
    Unbekannt
    Multibeam bathymetry raw data (EM 120 echosounder entire dataset) of RV SONNE during cruise SO223T (2024)
    PANGAEA
    Details
    Publikationsdatum: 2024-04-20
    Beschreibung: Multibeam bathymetry raw data using the ship's own Kongsberg (Simrad) EM 120 multibeam echosounder was not continuously recorded during RV SONNE cruise SO223T. Data was recorded on 10 days between 2012-09-13 and 2012-10-03. This dataset contains a mostly elongated transit survey in the Philippine Sea, also crossing the NW Rota-1 Seamount, Kengyu Seamount, Nishi-Yusei Seamount, Furo Seamount and Kanami Seamount. The approximate average depth of the entire dataset is around 4500m. The data are archived at the Federal Maritime and Hydrographic Agency of Germany (Bundesamt für Seeschifffahrt und Hydrographie, BSH) and provided to PANGAEA database for data curation and publication. No ancillary sound velocity profiles (SVP) files from the cruise are archived at the BSH, thus no SVP files are added to this dataset. However, data analysis of the multibeam raw data revealed that SVP has been changed during the survey. This publication is conducted within the efforts of the German Marine Research Alliance in the core area 'Data management and Digitalization' (Deutsche Allianz Meeresforschung, DAM). Data are unprocessed and therefore contains incorrect depth measurements (artifacts) without further processing. Note that refraction errors can be expected due to the lack of proper SVP. Overall, it appears that the data quality is rather good since the gridded hillshade data showed relatively few obstacles. Data can be processed e.g. with the open source software package MB-System (Caress, D. W., and D. N. Chayes, MB-System: Mapping the Seafloor, http://www.mbari.org/products/research-software/mb-system/, 2023).
    Schlagwort(e): Bathymetry; Binary Object; Binary Object (File Size); Binary Object (MD5 Hash); Binary Object (Media Type); Comment; DAM_Underway; DAM Underway Research Data; Data file recording distance; Data file recording duration; DATE/TIME; ELEVATION; Event label; Extracted from file; Extracted with MB-System; File content; Kongsberg datagram raw file name; LATITUDE; LONGITUDE; Multibeam Echosounder; Number of pings; Ship speed; SO223T; SO223T_0_Underway-1; Sonne; Start of data file, depth; Start of data file, heading; Start of data file recording, date/time; Start of data file recording, latitude; Start of data file recording, longitude; Stop of data file, depth; Stop of data file, heading; Stop of data file recording, date/time; Stop of data file recording, latitude; Stop of data file recording, longitude; Swath-mapping system Simrad EM-120 (Kongsberg Maritime AS); TransGeoBioOc
    Materialart: Dataset
    Format: text/tab-separated-values, 7366 data points
    Standort Signatur Einschränkungen Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    DATA PANGAEA
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...