Zooplankton in hollow-pools (using raised bogs in Vologda oblast, Russia, as an example)

Data on the biodiversity, structure, and seasonal dynamics of zooplankton communities in hollowpools of raised bogs in Vologda oblast are presented for the first time. The fauna of zooplankton communities in hollow-pools totals 38 species of plankton invertebrates (Rotatoria, 12; Cladocera, 19; and Copepoda, 7), and is mainly presented by acidophilic and sphagnophilic species. The water bodies are characterized by a high abundance and biomass of zooplankton organisms. The diversity and productivity of the zooplankton community increase with an increase in the area and depth of hollow-ponds. The seasonal dynamics of the abundance and biomass of zooplankton is similar in all groups of hollow-pools and depends on changes in the dominant complex of invertebrates.     

Peculiarities of under-ice zooplankton in the Curonian and Vistula Lagoons of the Baltic Sea

In the Vistula and Curonian lagoons, respectively, 7 and 9 taxa of under-ice zooplankton have been recorded. Copepoda and rotifera were dominant. Throughout the year, the complex of dominant species was generally constant in the Vistula Lagoon and changed considerably in the Curonian Lagoon. The zooplankton accumulation was found in the surface layer in the Curonian Lagoon, which was due to favorable oxygen conditions and phytoplankton accumulation under the ice.     

Long-term variability of the trophic status of the Curonian and Vistula Lagoons of the Baltic Sea

Based on an analysis of long-term (1991–2007) hydrological and hydrochemical data, as well as data on phytoplankton primary production, the ecological state of the Curonian and Vistula Lagoons of the Baltic Sea is assessed. The main abiotic factors influencing the trophic status of the lagoons are indicated. Water temperature is the key factor determining phytoplankton production and abundance in the Curonian Lagoon. An intensive warming-up of the lagoon water in the 1990s and 2000s (a possible result of climate warming) combined with freshwater and a slow-flow velocity created the conditions for the mass development of bluegreen algae. Despite a significant reduction in the external nutrients load, the occurrences of water hyperblooms” become more frequent, which points to a continuation of the eutrophication processes in the lagoon. The biological productivity of the Vistula Lagoon is below the potentially possible level because hydrodynamic activity and brackish water prevent the intensive development of blue-green algae. The increase in water temperature in the 1990s and 2000s had no significant effect on the ecological state of the lagoon.     

Correlation of enzyme thermostability and its surface hydrophobicity (using a modified alpha-chymotrypsin as an example)

Basing on the hypothesis that contact of hydrophobic surface clusters of proteins with water is thermodynamically disadvantageous, it is suggested to carry out the hydrophilization of protein surface by covalent modification in order to increase its thermostability. Hydrophilic fragments were introduced into the surface of alpha-chymotrypsin using acylation by anhydrides of aromatic carboxylic acids and reductive alkylation by aliphatic aldehydes. As a result of the hydrophilization the stability of the enzyme against irreversible thermoinactivation increased thousand-fold. The correlation is observed between the degree of hydrophilization of the protein surface and the increase in thermostability of modified alpha-chymotrypsin. The level of thermostability achieved by covalent modification of alpha-chymotrypsin is practically equal to thermostability of proteinases from extreme thermophiles, the most stable proteolytic enzymes currently known.     

Plankton and ecological status of watercourses in territories of various types (an example of Voronezh oblast)

The differences in the bacterio- and zooplankton communities of small- and medium-sized watercourses classified on the specifics of natural processes and consequences of anthropogenic activity in the territory of Voronezh oblast are described. Soil erosion, along with contamination of surface waters by industrial and municipal sewage and pesticides, has the greatest impact. The water current velocity, contamination by organic matter and nutrients, and the extent of macrophyte overgrowth affect the quantitative and qualitative composition of plankton in local parts of the studied watercourses.     

Sulfate reduction, methanogenesis, and methane oxidation in the upper sediments of the Vistula and Curonian Lagoons, Baltic Sea

Microbiological, biogeochemical, and isotope geochemical investigations of the upper sediments of the Vistula and Curonian lagoons, Baltic Sea, were carried out. High content of organic matter in the sediments was responsible for the high numbers (over 10¹⁰ cells cm^?3) and activity of heterotrophic microorganisms. The calculated integral rates of dark CO₂ assimilation for the upper 30 cm of the sediments varied 12.5 to 38.8 mmol m^?2 day^?1 and were somewhat higher in the Curonian Lagoon than in the Vistula Lagoon. Integral rates of sulfate reduction were higher in the more saline Vistula Lagoon. Rapid consumption of sulfates of the pore water resulted in intensified methanogenesis, with significantly higher rates detected in the silts of the Curonian Lagoon. High rates of methanogenesis in the Curonian Lagoon correlated with higher methane levels in its upper sediments and near-bottom water. The highest rates of methane oxidation were detected in the uppermost sediment horizons (oxidized or slightly reduced), which was an indication of the barrier role of aerobic methanotrophic bacteria. The calculated methane flows from the sediments into the water column were 0.45 and 0.007 mmol m^?2 day^?1 for the Vistula and Curonian Lagoons, respectively. Low methane flow from the sediments of the Curonian Lagoon resulted probably from the specific weather (wind) conditions during sampling. The near-stormy conditions in the Curonian Lagoon caused sediment detachment, resulting in methane release into the water column.     

Changes in the properties of enterocyte membrane structures in acholia using carbohydrases with different microtopographies as an example

The level of surface and intracellular carbohydrases was compared in rats with complete chronic loss of bile. The function of glycocalyx marke (adsorbed amylase) proved to be deranged much more in comparison with the function of the plasmic membrane proper marker (invertase).     

Population of hortobiontic heteropterans in urbanized territories (with Kemerovo as an example)

Hortobiontic Heteroptera in the city of Kemerovo are represented by 71 species of 50 genera and 12 families, with the dominating family Miridae. The richest assemblages as to the number of species were observed in lawns.     

Reproductive strategy of the alien Ponto-Caspian cladocerans Cercopagis pengoi (Ostroumov, 1891) in the Baltic Sea (by example of the Vistula Lagoon)

Early and prolonged sexual reproduction has been registered in the population of Cercopagis pengoi within the Vistula Lagoon relative to its original habitat. Decrease in the role of parthenogenesis and increase in the frequency of gamogenesis have been registered in the population under study. It has been accompanied by reduction in the average number of parthenogenetic eggs per female and increase in the production of gamogenetic eggs relative to the Caspian Sea.     

DNA-repair modulation using derivatives of 1,4-dihydroisonicotinic acid as an example

The influence of two derivatives of 1,4-dihydroisonicotinic acid on DNA-repair involved in chemical mutagenesis in Drosophila germ cells has been investigated. The compounds tested decreased the level of EMS-induced chromosome breakage and point mutations due to stimulation of maternal repair of DNA primary damage induced in spermatozoa as well as due to activation of DNA-repair in larvae and imago premeiotic stages of Drosophila males. Deficiency of DNA-repair systems leads to decrease in female and male germ-cell sensitivity to antimutagen action.     

Suitability of different vegetation structure types as habitat for the whinchat (Saxicola rubetra)

In biocoenological investigations in grasslands of southwestern Germany vegetation structure types were distinguished by considering physiognomical characteristics. The mapping of these types formed the basis for the determination of habitat preferences of the whinchat. By comparing supply and demand for the various structure types the (relative) habitat preference could be quantified. There was a dependency of the habitat utilization on the density of available hunting perches, on the food supply and on the mowing dates of grassland. By assigning the structure types to the plant associations of the investigation area the spectrum of structure types within each plant association could be shown and the suitability of vegetation types for the whinchat delineated.Paper delivered: XIX Congress of the Gesellschaft für Ökologie (FRG), Osnabrück, FRG: 1989-10-9/12     

Cytogenetic peculiarities of cell genesis in apical meristems under gametophytic apomixis (using autonomous apomicts of the Asteraceae as an example)

Cytogenetic peculiarities of cell genesis in apical meristems of apomicts has been analyzed using a series of the Asteraceae species as an example. The extent to which aneu- and mixoploids are spread among plants in the investigated populations of the Asteraceae species is so high (up to 30-60% of the studied plants and their offspring), that it seems reasonable to suppose that their rise is a natural phenomenon. It has been shown that in the aposporous facultative apomict Pilosella officinarum microgametophyte is a relatively stable element of the seed reproduction system from the point of view of caryotypical variation.     

Analysis of fish parasitofauna in Vistula Lagoon (the Baltic Sea)

The characteristics of parasitofauna (81 species) of 15 fish species from Vistula Lagoon (the Baltic Sea) are given. Parasites with a direct developmental cycle dominate. Parasites with a complicated developmental cycle are represented mainly by species developed through zoobenthos. Some of the parasites testify to the deterioration of the ecological state of the lagoon. A zoogeographic analysis of fish parasitofauna has shown the presence of five faunistic complexes. In Vistula Lagoon freshwater species dominate, but marine species are also recorded. Species that appeared in the lagoon as a result of human commercial activity are also registered.