4 resultados para Euglenophyta

em Publishing Network for Geoscientific


Relevância:

10.00% 10.00%

Publicador:

Resumo:

At present time, there is a lack of knowledge on the interannual climate-related variability of zooplankton communities of the tropical Atlantic, central Mediterranean Sea, Caspian Sea, and Aral Sea, due to the absence of appropriate databases. In the mid latitudes, the North Atlantic Oscillation (NAO) is the dominant mode of atmospheric fluctuations over eastern North America, the northern Atlantic Ocean and Europe. Therefore, one of the issues that need to be addressed through data synthesis is the evaluation of interannual patterns in species abundance and species diversity over these regions in regard to the NAO. The database has been used to investigate the ecological role of the NAO in interannual variations of mesozooplankton abundance and biomass along the zonal array of the NAO influence. Basic approach to the proposed research involved: (1) development of co-operation between experts and data holders in Ukraine, Russia, Kazakhstan, Azerbaijan, UK, and USA to rescue and compile the oceanographic data sets and release them on CD-ROM, (2) organization and compilation of a database based on FSU cruises to the above regions, (3) analysis of the basin-scale interannual variability of the zooplankton species abundance, biomass, and species diversity.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Studies were carried out in the northeastern Sea of Okhotsk, in the zone of interaction of the West Kamchatka and Compensating Currents at the beginning of spring seasonal succession from March 23 to April 14,1998. Samples for analysis of pigmentary and species compositions of phytoplankton were taken from the sea surface layer, depth 0.5 m. To reduce influence of micropatchiness on phytoplankon distribution at each station subsamples 0.7-1 l were collected every 50-100 m. These subsamples were used to make integral samples 4.5-8.0 l. Phytoplankton biomass and concentration of chlorophyll a varied from 18.7 to 490.9 mg/m**3 and from 0.129 to 2.422 mg/m**3, respectively. Total concentration of phytoplankton pigments varied from 0.622 to 6.679 mg/m**3. In samples studied 51 species of microalgae from 5 orders were found. In terms of the number of species, Bacillariophyta (31 species) and Dinophyta (15 species) prevailed. Diatomaceous algae make up more than 80% of the total phytoplankton biomass in waters of the Compensating Current, from 50 to 80% in intermediate waters, and less than 50% in waters of the West Kamchatka Current. Phytoplankton populations consisting primarily of diatoms were characterized by very low chlorophyll a to biomass ratio (0.1 %). It is three times lower than the ratio observed in phytoplankton populations that were close by species composition and size composition in this area in the late April-early May 1996.

Relevância:

10.00% 10.00%

Publicador: