|
Genetic markers in studies on dreissenides (Dreissenidae, Bivalvia). – Voroshilova I. S. – This review summarizes literature data of the genetic markers used in studies of dreissenide invasions. Causes of genetic differences between local populations are discussed. It is shown that information about the genetic diversity of populations obtained by marker polymorphism analysis should be compared to study invasion directions.
Key words: invasion, Dreissenidae, genetic markers.
<<< To Contents
Underyearlings of Dreissena (Dreissenidae, Bivalvia) in the phytophylic communities in the mouth area of the Rybinsk reservoir tributary. – Zhgareva N. N. – Data on the distribution, numbers and biomass of dreissenid underyearlings in macrophyte thickets in several zones of the mouth area of a small tributary to the Rybinsk reservoir are presented. The highest density and biomass of underyearlings are observed in the transient zone of the reservoir and the river mouth cross-section line. It is shown that the number of dreissenid underyearlings inhabiting the mouth area has not changed considerably in the years unfavorable by meteorological conditions.
Key words: dreissenids, underyearlings, number, biomass, river mouth area, reservoir tributary.
<<< To Contents
Impact of Dresissenid (Bivalvia) irradiation on the benthic communities composition in Middle Kama reservoirs. – Istomina A. M. – Dreissenid irradiation and quantitative rates in the benthic communities of the Kama and Votkinsk reservoirs are discussed. The impact of these mollusks on the structure of benthic communities of the studied water bodies is estimated.
Key words: Dreissena polymorpha, D. bugensis, macrobenthiñ community, Kama reservoir, Votkinsk reservoir.
<<< To Contents
Antioxidant status of freshwater bivalves Dreissena polymorpha and D. bugensis (Dreissenidae, Bivalvia) from the Volga reach of the Rybinsk reservoir. – Klimova Y. S. and Chuiko G. M. – Peculiarities of the antioxidant defense system (ADS) in the soft tissues of the freshwater bivalves Dreissena polymorpha and D. bugensis from the Volga Reach of the Rybinsk reservoir were studied. The activities of several antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione reductase (GR), and the content of a low-molecular-weight antioxidant such as reduced glutathione (GSH), as well as the content of the products of lipid peroxidation (LPO) – malondialdehyde (MDA), and those of oxidative modification of proteins (OMP) – carbonyl groups (CG), were evaluated. Comparative analysis of ADS components and LPO and OMP products in mollusks depending on species, sex, size, and season was conducted. Specific peculiarities of the examined indicators have been revealed. It is found that D. polymorpha differs from D. bugensis by lower levels of antioxidant enzyme activities and MDA and CG contents, but at the same time it has a higher level of reduced GSH. Analysis of seasonal features of ADS has revealed that, regardless of gender, the values of such indicators as CAT, SOD, and reduced GSH in both bivalve species increase from November till May. Other parameters change in different directions: they either increase or decrease both in females and males.
Key words: antioxidant enzymes, lipid peroxidation, oxidative modification of proteins, freshwater bivalves.
<<< To Contents
Veliger larvae of Dreissena (Bivalvia, Dreissenidae) in the plankton foodweb of the Rybinsk reservoir. – Lazareva V. I., Kopylov A. I., Sokolova E. A., and Pryanichnikova E. G. – The abundance dynamics of adult dreissenids (Dreissena polymorpha (Pallas) and D. bugensis Andrusov) and their larvae, the spatial distribution of the abundance of veligers and their role in functioning of the plankton community have been analyzed on the basis of the data of our long-term monitoring (2004 – 2013) in the Rybinsk reservoir. Dreissena veligers are most abundant in the summer (July – August) when their number is comparable with that of crustaceans filter feeders and their biomass is similar to that of rotifers. Before 2010 the production of veligers during the vegetation season was 5% of the production of metazooplankton, and the food intake was ~1% of the primary production of phytoplankton. Pelagic invertebrate predators consumed about 90% of the production of veligers for the vegetation period. After 2010, the abundance of dreissenid larvae and their functional characteristics decreased by 5 – 6 times. Trophic relationships between zooplankton and veligers are discussed.
Key words: reservoir, plankton, veliger larvae of Dreissena, abundance, production, food requirements, trophic interaction.
<<< To Contents
Dreissenids (Bivalvia, Dreissenidae) in the mouth areas of small tributaries of the Rybinsk reservoir. – Perova S. N. – The distribution of two dreissenids species in the river mouth areas of tributaries of the Rybinsk reservoir were studied. The highest abundance and biomass of Dreissena polymorpha and D. bugensis mussels were recorded in the river mouth ranges and in the reservoir. It is noted that the abundance of the dreissenids in 2010 – 2011 was significantly lower as compared with 2007 – 2008.
Key words: dreissenids, small river, mouth area, reservoir, tributary.
<<< To Contents
Dreissenid species (Mollusca, Dreissenidae) in the Upper Volga reservoirs. – Pryanichnikova E. G. – The results of our long-term studies of populations of two dreissenid species (Dreissena polymorpha Pallas, 1771 and D. bugensis Andrusov, 1897) in the Rybinsk and Gorky reservoirs are analyzed. New habitats of D. bugensis in the Rybinsk reservoir were disclosed.
Key words: mollusks, Dreissena polymorpha, Dreissena bugensis.
<<< To Contents
Macrozoobenthos of joint communities of two dreissenid species (Mollusca, Dreissenidae) in the Rybinsk reservoir. – Pryanichnikova E. G. – The results of our studies of the macrozoobenthos structure in joint communities of two dreissenid species (Dreissena polymorpha Pallas, 1771 and D. bugensis Andrusov, 1897) in the Rybinsk reservoir are presented. The maximum species richness and macrozoobenthos abundance are typical for a biocenosis where D. polymorpha predominates. With the increase of D. bugensis these values reliably reduce. In both types of dreissenid biocenoses the most important role is played by oligochaetes with the predominance of Potamothrix moldaviensis Vejdovsky et Mrazek, 1902.
Key words: macrozoobenthos, Dreissena polymorpha, Dreissena bugensis, Rybinsk reservoir.
<<< To Contents
Perennial dynamics of dreissenid (Dreissenidae, Bivalvia) populations and communities in the benthos and periphyton of the cooling pond of the Chernobyl NPS. – Silayeva A. A., Protasov A. A., and Morozovskaya I. A. – The results of our long-term research of the communities of Zebra mussel and Quagga mussel in the cooling pond of the Chernobyl nuclear power plant (Ukraine) are presented. Peculiarities of the sequential invasion of these two Dreissenid species and the formation of consortium-type communities by them are considered.
Key words: Dreissenids, Dre³ssena polymorpha, Dre³ssena bugensis, periphyton, benthos, population, community, cooling pond, Chernobyl nuclear power plant.
<<< To Contents
Effect of anomalously high temperatures on the abundance of dreissenid veligers (Bivalvia, Dreissenidae) in plankton of the Rybinsk reservoir. – Sokolova E. A. – The abundance of dreissenid veligers in the plankton of the Rybinsk reservoir was estimated during several years with different temperature conditions. The abundance of dreissenid veligers and their fraction in the total zooplankton abundance decreased significantly at an extremely high water temperature in 2010 and at temperatures higher than the average one in 2011, when the species richness and abundance of zooplankton increased. The decrease in the dreissenid veligers abundance was most significant in 2010.
Key words: dreissenid veligers, abundance, zooplankton, Rybinsk reservoir, anomalously high temperature.
<<< To Contents
Some issues of weight reconstruction of Dreissena polymorpha (Pallas) (Dreissenidae, Bivalvia) consumed by fish. – Bezmaternykh V. V. – The form and parameters of the equation relating the fresh weight and the size of the umbo-myophorous structure (i.e. the umbo thickness plus the septa median size) for the Kama, Votkinsk, Karman and Rybinsk reservoirs Dreissena polymorpha (Pall.) were revealed. The parameters of the said relation differ between the water bodies studied, the generalized equation being W = 71.37 × U3 and having a high determination coefficient (0.9).
Key words: Dreissena polymorpha, fish trophology, equation, weight, reconstruction.
<<< To Contents
|
