779 resultados para Calanus finmarchicus
Resumo:
The Longitudinale 1987-1991dataset contains zooplankton data collected from May to October 1987-1991 in 14 station allong 2 transect paralel to the romanian littoral. Zooplankton sampling was undertaken at 14 stations where samples were collected using a Juday closing net in the 0-10, 10-20, 20-30 and 30-40 layer (depending also on the water masses). The dataset includes samples analysed for mesozooplankton species composition and abundance. Sampling volume was estimated by multiplying the mouth area with the wire length. Taxon-specific mesozooplankton abundance was count under microscope. Total abundance is the sum of the counted individuals. Total biomass Fodder, Rotifera , Ctenophora and Noctiluca was estimated using a tabel with wet weight for each species an stage.
Resumo:
The Est Constanta 1978 dataset contains zooplankton data collected monthly from January 1978 to december 1978 allong a 5 station transect in front of the city Constanta (44°10'N, 28°41.5'E - EC1; 44°10'N, 28°47'E - EC2; 44°10'N, 28°54'E - EC3; 44°10'N, 29°08'E - EC4; 44°10'N, 29°22'E - EC5). Zooplankton sampling was undertaken at 5 stations where samples were collected using a Juday closing net in the 0-10, 10-25, 25-50m layer (depending also on the water masses). The dataset includes samples analysed for mesozooplankton species composition and abundance. Sampling volume was estimated by multiplying the mouth area with the wire length. Taxon-specific mesozooplankton abundance was count under microscope. Total abundance is the sum of the counted individuals. Total biomass Fodder, Rotifera , Ctenophora and Noctiluca was estimated using a tabel with wet weight for each species an stage.
Resumo:
The Gurile Dunarii 1977 dataset contains zooplankton data collected in April and September 1977 in 14 station allong 3 transect in front of the Danube Delta. Zooplankton sampling was undertaken at 14 stations where samples were collected using a Juday closing net in the 0-10, 10-20, 20-30, 30-40 and 40-50m layer (depending also on the water masses). The dataset includes samples analysed for mesozooplankton species composition and abundance. Sampling volume was estimated by multiplying the mouth area with the wire length. Taxon-specific mesozooplankton abundance was count under microscope. Total abundance is the sum of the counted individuals. Total biomass Fodder, Rotifera , Ctenophora and Noctiluca was estimated using a tabel with wet weight for each species an stage.
Resumo:
The MOOGLI dataset contains mesozooplankton data collected in 1998-1999 in the Gulf of Lion (North Western Mediterranean Sea). Zooplankton taxonomy-related abundance per unit volume of the water column.
Resumo:
Feeding activity, selective grazing and the potential grazing impact of two dominant grazers of the Polar Frontal Zone, Calanus simillimus and Rhincalanus gigas, and of copepods < 2 mm were investigated with incubation experiments in the course of an iron fertilized diatom bloom in November 2000. All grazers were already actively feeding in the low chlorophyll waters prior to the onset of the bloom. C. simillimus maintained constant clearance rates and fed predominantly on diatoms. R. gigas and the small copepods strongly increased clearance and ingestion of diatoms in response to their enhanced availability. All grazers preyed on microzooplankton, most steadily on ciliates, confirming the view that pure herbivory appears to be the exception rather than the rule in copepod feeding. The grazers exhibited differences in feeding behavior based on selectivity indices. C. simillimus and R. gigas showed prey switching from dinoflagellates to diatoms in response to the phytoplankton bloom. All grazers most efficiently grazed on large diatoms leading to differences in daily losses for large and small species, e.g. Corethron sp. or Thalassionema nitzschioides. Species-specific diatom mortality rates due to grazing suggest that the high feeding activity of C. simillimus prior to and during the bloom played a role in shaping diatom population dynamics
Resumo:
The SESRU_02_mesozooplankton dataset contains data collected in September 2008 at 15 stations located between 37°E and 39.5°E and between 42.4°N and 44.5°N in the north-eastern Black Sea. Samples were collected with a Juday net. Juday net: Vertical tows of a closing Juday net, with mouth area 0.1 m**2, mesh size 180 µm. Samples were taken from different layers. Towing speed: 1m/s. Samples were preserved by a 4% formaldehyde sea water buffered solution. Sampling volume was estimated by multiplying the mouth area with the wire length. Integrated samples were taken from the lower boundary of the oxic zone to the surface, stratified samples were taken according to CTD-profiles: samples were taken from the following depth strata: 1) the upper mixed layer (UML); 2) the layer of high temperature gradients (from the upper boundary of thermocline to the depth of 8 deg C temperature); 3) cold Intermediate layer (CIL) - the layer with the T< 8 deg C; 4) from the depth of sigma theta = 15.8 (oxycline) to the lower boundary of CIL; 5) from the depth of sigma theta = 16.2 to the depth of sigma theta = 15.8. Samples were analysed for zooplankton species and stage composition and abundance. The entire sample or an aliquot (1/2 to ¼) was analyzed under the binocular microscope. Mesozooplankton species and stages were identified and enumerated; meroplankton were identified and enumerated at higher taxonomic level. Taxonomic identification was done at Shirshov Institute of Oceanology using the relevant taxonomic literature (Rose, 1933, Brodsky, 1950 and Internet resources).
Resumo:
The dataset is based on samples collected in the autumn of 2001 in the Western Black Sea in front of Bulgaria coast. The whole dataset is composed of 42 samples (from 19 stations of National Monitoring Grid) with data of mesozooplankton species composition abundance and biomass. Samples were collected in the layers 0-10, 0-20, 0-50, 10-25, 25-50, 50-100 and from bottom up to the surface at depths depending on water column stratification and the thermocline depth. Zooplankton samples were collected with vertical closing Juday net,diameter - 36cm, mesh size 150 µm. Tows were performed from surface down to bottom meters depths in discrete layers. Samples were preserved by a 4% formaldehyde sea water buffered solution. Sampling volume was estimated by multiplying the mouth area with the wire length. Mesozooplankton abundance: The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Kremena Stefanova using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972). Taxon-specific abundance: The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Copepods and Cladoceras were identified and enumerated; the other mesozooplankters were identified and enumerated at higher taxonomic level (commonly named as mesozooplankton groups). Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Kremena Stefanova using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972).
Resumo:
The dataset is composed of 50 years of approximately monthly mesozooplankton sampling at station Stoncica. The volume of filtered water was estimated assuming 70% efficiency of the Hensen 330 micrometer mesh size net according to Laevastu (1958). Subsamples amounting to 1/20 of the catch were counted for the most representative groups. The whole catch was examined for rare species.The results in the datatables are recalculated to (#/m**3).
Resumo:
The benthic fauna was investigated during the expedition ANT-XXIV/2 (2007/08) in relation to oceanographic features, biogeochemical properties and sediment characteristics, as well as the benthic, pelagic and air-breathing fauna. The results document that Maud Rise (MR) differs distinctly from surrounding deep-sea basins investigated during previous Southern Ocean expeditions (ANDEEP 2002, 2005). Considering all taxa, the overall similarity between MR and adjacent stations was low (~20% Bray-Curtis-Similarity), and analyses of single taxa show obvious differences in species composition, abundances and densities. The composition and diversity of bivalves of MR are characterised by extremely high abundances of three species, especially the small sized Vesicomya spp. Exceptionally high gastropod abundance at MR is due to the single species Onoba subantarctica wilkesiana, a small brooder that may prey upon abundant benthic foraminiferas. The abundance and diversity of isopods also show that one family, Haplomunnidae, occurs with a surprisingly high number of individuals at MR while this family was not found at any of the 40 bathyal and abyssal ANDEEP stations. Similarly, polychaetes, especially the tube-dwelling, suspension-feeder fraction, are represented by species not found at the comparison stations. Sponges comprise almost exclusively small specimens in relatively high numbers, especially a few species of Polymastiidae. Water-column sampling from the surface to the seafloor, including observations of top predators, indicate the existence of a prospering pelagic food web. Local concentrations of top predators and zooplankton are associated with a rich ice-edge bloom located over the northern slope of MR. There the sea ice melts, which is probably accelerated by the advection of warm water at intermediate depth. Over the southern slope, high concentrations of Antarctic krill (Euphausia superba) occur under dense sea ice and attract Antarctic Minke Whales (Balaenoptera bonaerensis) and several seabird species. These findings suggest that biological prosperity over MR is related to both oceanographic and sea-ice processes. Downward transport of the organic matter produced in the pelagic realm may be more constant than elsewhere due to low lateral drift over MR.