Home – Home – Jornals – Contemporary Problems of Ecology 2010 number 4

The biogenic detritus that accumulated for more than 7 months in the microcosms with Viviрarus viviрarus, Unio pictorum, Ceratophyllum demersum, contained several elements. The concentrations of those elements in the detritus of this type were measured for the first time using neutron activation analysis (NAA). The concentrations of the elements decreased in the order: Ca > Zn > Ba > Br > Ce > Se > Nd > La > U > Hf > Sb > Th > Sm > S> Cs > Au. The new data added some new information to the modern vision of the polyfunctional role of the biota in the functioning of water systems.

This study anаlyses in detail and classifies the factors of negative anthropogenic impacts on hydrophilic flora. The natural local and regional changes dependent on the climatic factors of the studied territory are considered.
The disappearing species and the species requiring protection are revealed.

Chemical composition of Propadayushchiy Stream that drains radioactive waste piles at the Kurung 1 Site (Mine 2) of Yuzhnoye deposit has been studied and the level of radioactive pollution of surface waters in the Elkon ore-bearing region within the territory of South Yakutia has been estimated. We found that the main source of anthropogenic pollution of surface waters in this region is radioactive waste piles which appeared in the zone of hypergenesis because of long-term and large-scale geological surveys for radioactive raw material.

In the phytoplankton of some studied waterbodies of the north-eastern part of West Siberia, Bacillariophyta belongs to the dominant group among 7 algae orders, with respect to the species diversity with the occurrence of the representatives of the class Centrophyceae from 27 up to 100 %. With the help of electron microscopy, the first complete data on the species composition of Centrophyceae class dominаting in the phytoplankton of Lake Delingde, the Delingde and the B. Kheta rivers were obtained (Aulacoseira - 3, Cyclostephanos - 1, Cyclotella - 5, Discostella - 1, Melosira - 1, Pliocaenicus - 1, Puncticulata - 1, Stephanodiscus - 6).
The list of the representatives of Centrophyceae class in River Taz was supplemented with Puncticulata radiosa. For the first time for the flora of West Siberia, the new species of Cyclotella genus were found: : C. arctica, C. comensis, C. vorticosa. This allowed us to define more exactly the ranges of these rare taxa and broaden the diagnoses of C. comensis and Stephanodiscus invisitatus.

Data on phytoplankton structure and physical-chemical parameters of the waters of the Anаbar, a large river of the Arctic basin, were obtained for the first time, The patterns of development of plankton algal groupings and the formation of the hydrochemical water regime in different sites of the river were determined. We also found a decrease in water quality at the river site where the enterprises of mining industry operate. The background data on the structure of phytoplankton and physicochemical parameters of the upper part of the Anabar will be the basis for monitoring under the industrial development of this river part in future.

Species composition and biomass indices of net animal plankton in four large lakes and 35 small ones from 10 regions situated between 69,5 and 67,5° of the northern latitude and ~87 and 92° of the eastern longitude examined in July-August 2001 and 2003-2004 are reported. The distribution of separate species and changes of the structure of the animal plankton are discussed from the viewpoint of the possible influence of climate warming.

Diatom complex found in the bottom sediments of mountainous, oligotrophic lakes of the Amguema river basin (Ervynajgytgyn, Matachingajgytkhyn, Ekitiki) is presented for the first time. In total, 385 species and subspecies of Bacillariophyceae from 69 genera were found in the sediments of the above-mentioned lakes. More than a quarter of the species comprising the revealed complex belongs to taxa characterized by limited distribution; half of them are characterized as rare forms. For each taxon, the data on the frequency of occurrence for Beringia region are provided. Three new combinations are suggested.

The degree of particiрation of the heat shock proteins of the low-molecular (small) HTP family (lmHSP) in the mechanisms of therm- and toxoresistivity in fresh-water organisms was investigated. Four endemic species of Lake Baikal were studied: Gmelinoides fasciatus (Stebb.), Eulimnogammarus cyaneus (Dyb.), E. vittatus (Dyb.), Ommatogammarus flavus (Dyb.) and the representative of the palaearctic fauna Gammarus lacustris Sars. The effect of temperature factor was evaluated in course of exposure at temperatures 20, 25, 30 °C, the action of the toxic factor was evaluated by exposure in cadmium chloride solutions with the concentrations 50, 10, 5, 0.5 and 0.05 mg/l. A trend to increasing content of the proteins of lmHSP family was observed as a common feature of all the species investigated; however, species-specific peculiarities of the character of synthesis of the protein under investigation were observed. It was concluded that the lmHSP participate in the mechanisms of thermo- and toxoresistivity in the investigated amphipoda species.

Results of the investigation of the species composition and distribution of the bacteria of Enterococcus genus in the water of Lake Baikal are presented, the degree of stability to antibiotics is also described. It is demonstrated that these bacteria live in the littoral regiosn of the lake. The microorganisms under investigation were not detected in the deep-water part of the lake. The number of isolated strains is 120, they were identified as E. faecium, E. avium, E. faecalis, E. mundii, E. hirae, E. durans, E. gallinаrum. In general, the enterococcus strains isolated from the water of Lake Baikal are characterized as sensitive to antibiotics. Nevertheless, enterococcus strains stable to antibiotics were isolated from the collection under investigation, including the strains for which an intermediate level of stability to vancomycin is characteristic.

It was established that the microbial community of the destructor bacteria in bottom sediments and crust of the soda lake Khilganta is able to develop within a broad range of pH and mineralization. The community of destructor bacteria functions in the most active manner under neutral or weakly alkaline conditions and at not very high salt concentration. The simultaneous action of two factors - high рН and salinity of the medium - leads to a decrease in the number of cells and a decrease in the destruction activity of the community.
The data obtained confirm the previous assumption that the destruction processes are suppressed in the case of high mineralization, which causes accumulation of the organic matter.

The composition of animal plankton was studied in thermokarst, glacial and meteorite lakes, canals, former river-beds of the basin of the Anаdyr, river. The number of taxa detected there is 174: 78 Rotatoria, 55 Cladocera, 41 Copepoda. The most diverse is the lake fauna: 51 taxa of Rotatoria, 48 Cladocera, and 37 Copepoda. In thermokarst lake Mayorskoe, 68 taxa were detected: 31 - Rotatoria, 14 - Cladocera, and 23 - Copepoda, whereas in the cold ultraoligotrophic lake Elgygytgyn there is only one cyclop species of the group scutifer Cyclops neymanаe Strel., though Rotatoria and Cladocera are present as allochthons. For Copepoda as example, the connections of the fauna of the Anadyr' with the European, North American and Japanese faunas were revealed.

The possibilities to use the Novosibirsk Water Reservoir for water-supply manаgement, including drinking water supply to the megapolis and the surrounding territories are considered. The features of the perennial formation of the hydrologo-hydrochemical regime and its influence on the ecological conditions of water consumption were revealed.

In the bottom sediments of the Magnitogorskoye reservoir, the total content of 35 elements was determined by means of X-ray fluorescence spectrometry using synchrotron radiation, and the concentrations of mobile forms of 10 metals were evaluated by means of atomic absorption spectrophotometry. The features of the statistical analysis of incomplete data were considered, and also the reasons of similarity and discrepancies of the data obtained by different chemical-analytical methods were discussed. With the use of principal component analysis, 4 paragenetic associations of elements were detected in the structure of the bottom sediments: the elements in the organic matter, the pelite fraction, pollutants from the Magnitogorsk metallurgical combine and pollutants from motor vehicles.

Studies of invertebrates inhabiting the stones of the shoal of a cooler reservoir demonstrated predominance of Oligochaeta from Naididae family in number, and Plumatella emarginаta in biomass. With the biomass of zooperiрhyton exceeding 100 g/m², the substrate roughness and brightness were found to affect the number and biomass; a correlation between the biomass of Plumatella emarginаta and the number of Oligochaeta was revealed.

Results of the accumulation of chemical elements in scum formed by evaporation of underground water used by the population of the Irkutsk and Tomsk Regions for water supply are presented in the paper. The levels of accumulation of heavy metals, including rare earth and radioactive ones, in the dry residues of scum are established.