Zooplankton communities in the Drake Passage through environmental boundaries: a snapshot of 2010, early spring.

Background: Spatial distribution of zooplankton communities influenced by various environmental factors is always important for understanding pelagic ecosystems. The area of the Drake Passage (Southern Ocean) is of particular interest owing to the high spatial and temporal variability of hydrological parameters affecting marine fauna. This study provides a survey of zooplankton composition and spatial distribution along a transect in the Drake Passage sampled during the 31th Cruise of RV "" in November, 2010.

Effect of invasive ctenophores Mnemiopsis leidyi and Beroe ovata on low trophic webs of the Black Sea ecosystem.

The study focuses on the impact of life excretion and mucus released by the "biological pollutants" invasive ctenophore Mnemiopsis leidyi and its predator Beroe ovata on the marine environment and lower trophic levels of the Black Sea ecosystem (bacteria, pico-phytoplankton, nano-autotrophic/heterotrophic flagellates, micro-phytoplankton, chlorophyll a, primary production (PP), micro-zooplankton). The chemical and biological variables were analysed in two sets of lab experiments with natural communities from mesotrophic (Gelendzhik) and eutrophic (Varna) coastal waters. While both species altered the chemical properties of experimental media, exerting structural and functional changes in the low food-web biological compartments, the results showed a stronger effect of B.

[Vertical distribution of radiolarians and their role in epipelagic communities of the West Pacific rise and the Gulf of California].

Vertical distribution of different groups of radiolarians and mesozooplankton (I = 0.2-3.0 mm) and the contribution of radiolarians to total biomass of bathometer-sampled zooplankton were studied in the epipelagic West Pacific Rise and the Gulf of California during 49th cruise of R/V "Akademik Mstislav Keldysh" (September-October, 2003).