Dmitrieva O.A.,Atlantic Scientific Research Institute of Marine Fisheries and Oceanography |
Semenova A.S.,Atlantic Scientific Research Institute of Marine Fisheries and Oceanography
Inland Water Biology | Year: 2011
The seasonal dynamics of phyto- and zooplankton, as well as their trophic interactions, were studied for the shallow freshwater hypereutrophic Curonian Lagoon in the Baltic Sea in 2007-2009. The water temperature and high concentrations of nutrients were the limiting factors in the seasonal dynamics of the studied communities. Decreases in the B z/B ph ratio and the grazing pressure of phytophagous zooplankton were observed over the last few decades due to the eutrophication process and cyanobacteria blooms. The large zooplankton consumes a significant amount of primary production (Chlorococcales and Bacillariophyta) when the predator pressure of the fish fry is absent. This grazing pressure may precondition cyanobacteria scum. © 2011 Pleiades Publishing, Ltd.
Naumenko E.N.,Atlantic Scientific Research Institute of Marine Fisheries and Oceanography
Inland Water Biology | Year: 2010
Regression models are built based on the literature and original data on the abundance, biomass, and production dynamics of zooplankton, taking into account the biology and feeding peculiarities of whitebait (Osmerus eperlanus morpha spirinhus Pallas) and Baltic herring (Clupea harengus membras L.) in the Curonian and Vistula lagoons. These models may be used to predict the commercial planktivorous fish yield. © 2010 Pleiades Publishing, Ltd.
Feldman M.V.,Atlantic Scientific Research Institute of Marine Fisheries and Oceanography
2006 IEEE US/EU Baltic International Symposium, BALTIC 2006 | Year: 2016
One of major components of aquatic ecosystems are macrophytes - the large metaphytes normally develop in conditions of exuberant humidification. This group of hydrobionts represents an initial part in circulation of matter and energy as primary producers of organic matter. Macrophytes influence chemical and physical properties of water by accumulation of nutrients. Besides they are habitats for many organisms at various stages of development, including nesting birds, fish eggs and larvae. That is why assessment of macrophyte store and accumulation of nutrients in macrophyte tissues became the one of important objectives of environmental monitoring and management. In August 2005 the geobotanical mapping of the Curonian Lagoon coast from the research vessel to evaluate distribution of reed (Phragmites communis Trin.) and bulrush (Scirpus lacustris L.) was conducted. The area of macrophyte thickets is approximately 480 ha for reed and 305 ha for bulrush. At the same time biomass samples of reed and bulrush (not less then 10 samples per one plant community, 61 samples in total) were taken along the coastline. The samples were weighed in air-dry state; the data were processed with the computer programs Microsoft Excel 97 and Statistica. The average air-dry biomass is 993 g/m2 for reed, and 470 g/m2 for bulrush. So the macrophyte store in the Russian part of the Curonian Lagoon is approximately 4766,4 tons of air-dry mass for reed and 1433,5 tons for bulrush. The average values of concentrations of phosphorus in tissues of dominating macrophyte species (in mgP/g of dry matter) sampled in August 2005 in the Curonian Lagoon and analysed with a photometer are 6,7 mgP/g for reed and 4,1 mgP/g for bulrush. For concentrations of nitrogen the values are 28,8 and 21,3 mgN/g accordingly. © 2006 IEEE.