944 resultados para Acartia clausi, c4, length
Resumo:
The "SESAME_IT3_ZooAbundance_0-50-100m_SZN" dataset contains data of mesozooplankton species composition and abundance (ind. m-3) from samples collected in the Sicily Channel in the early spring of 2008 (17,18 March) during the SESAME-WP2 cruise IT3. Samples were collected by vertical tows with a closing WP2 net (56 cm diameter, 200 µm mesh size) in the following depth layers: 100-200 m, 50-100 m, 0-50 m. Sampling was always performed in light hours with the exception of station S-IT3-03 where zooplankton were collected in dark hours. A flowmeter was applied to the mouth of the net, however, due to its malfunctioning, the volume of filtered seawater was calculated by multiplying the the area by the height of the sampled layer from winch readings. After collection, each sample was split in two halves (1/2) after careful mixing with graduated beakers. Half sample was immediately fixed and preserved in a formaldehyde-seawater solution (4% final concentration) for species composition and abundance. The other half sample was kept fresh for biomass measurements (data already submitted to SESAME database in different files).Here, only the zooplankton abundance of samples in the upper layers 0-50 m and 50-100 m are presented. The abundance data of the samples in the layer 50-100 m will be submitted later in a separate file. The volume of filtered seawater was estimated by multiplying the the area by the height of the sampled layer from winch readings. Identification and counts of specimens were performed on aliquots (1/20-1/5) of the fixed sample or on the total sample (half of the original sample) by using a graduate large-bore pipette. Copepods were identified to the species level and separated into females, males and juveniles (copepodites). All other taxa were identified at the species level when possible, or at higher taxonomic levels. Taxonomic identification was done according to the most relevant and updated taxonomic literature. Total mesozooplankton abundance was computed as sum of all specific abundances determined as explained above.
Resumo:
The SESAME dataset contains mesozooplankton data collected during April 2008 in the North-Western part of Black Sea (between 44°46' N and 42°29'N latitude and 28°64'E and 30°59'E longitude). Mesozooplankton sampling was undertaken at 9 stations where samples were collected using a Hensen net in the 0-10, 10-25, 25-50, 50-100, 100-150, 150-200 m layer. The dataset includes 29 samples analysed for mesozooplankton species composition and abundance. The entire sample or an aliquot (1/2 to 1/4) was analyzed under the binocular microscope. Calculations of zooplankton abundance are made by the following formulae, in accordance with the Report of the third ICES/HELCOM workshop on quality assurance of Biological measurements Warnemünde, Germany, 1996. M - number of counted specimens (ind.), Vf - volume of filtrated water (m³), and K - counted part of sample. (http://www2008.io-warnemuende.de/research/helcom_zp/documents/qa_zp_part.pdf)
Resumo:
Samples of zooplankton were collected in the Barents Sea during cruise 11 of R/V Akademik Sergey Vavilov in September-October 1997. Three different sampling methods were used: 30 l bottle, Judey net, and BR net. More than 40 species of zooplankton were revealed. The greatest species diversity occurred in zones of junction of waters of different origin. Within the 100 m upper water layer zooplankton biomass was rather high: aver. 32 g/m**2. The highest biomass was observed in the northeastern part of the region under study and over the shelf of the Russkaya Gavan' Bay. The lowest biomass occurred in the southern part and in the region of the Gusinaya Banka. The average autumn value of zooplankton biomass in the 100 m upper layer (321 mg/m**3) slightly exceeded the multiannual average for the summer period (200 mg/m**3)