Home – Home – Jornals – Contemporary Problems of Ecology 2012 number 3

Vegetational changes, namely pyrogenic, lithogenic, floodplain, Aeolian, and waterlogging, are briefly characterized. Fire events are among the basic ecological factors determining the differentiation of plant cover and vegetation diversity over the territory under consideration.

New procedure was proposed for the investigation of atmospheric radioactivity in the surface air layer through evaluation of specific activity of artificial and natural radionuclides in aerosol sink. Dry deposition of aerosol particles was described. Collection of aerosol is carried out using a passive sampler in which chemically inert fibrous and powdered materials are used as sorption substrate. Analysis of experimental results characterizing the features of radionuclide distribution in aerosol sink during their introduction into coniferous tree stand is presented.

Threshold concentrations of elements in fresh water necessary for the survival of Spirogira sp. were determined.
The concentrations of sodium, potassium, calcium, magnesium in the algae was maintained at a level of (84,3 ± 0,8), (23,9 ± 0,5), (3,5 ± 0,2), (8,5 ± 0,2) mmol/kg of dry mass, respectively, and water (92,5 ± 0,21) %. It was shown that the threshold concentrations of sodium, potassium, calcium, magnesium in water, determining the boundaries of the range of Spirogyra sp. in fresh water reservoirs are equal to 0,003-0,007, 0,002-0,003, 0,0017-0,0022, 0,0012-0,0018 mmol/l, respectively. A decrease in water mineralization was accompanied by a substantial increase in the gradient of cation concentration between the algae and the environment, thus enhancing the load on the systems maintaining water-salt metabolism. It was shown on the basis of comparative analysis that Spirogyra sp., being the primary link of the trophic chain, possesses a more efficient ability to extract ions from water in comparison with freshwater animals.

This article deals with the results of the study of diatom algae of lake Shira. The list of found algae contains 95 species (including subspecific taxa - 126). Brief ecological and geographical anаlysis of the algal flora is made.

In the studied waterbodies of the north-east of Western Siberia, Bacillariophytas dominаte in the flora of planktonic organisms by species abundance. Among them, class Pennаtophyceae is distinguished by the highest species richness. The first electro-microscopic studies of pinnate diatom algae allowed obtaining complete data on the species composition of Pennаtophyceae at the modern level. 213 taxa from 53 genera including 98 new for the region, 56 new and rare for the flora of Russia and forms identified only to the genus have been found. The taxonomy of the genera Nitzchia, Stauroneis, Pinnularia, Navicula s.s. is the most rich.

Mass vegetation of cyanobacteriae Spirulina fusiformis Woronich. was discovered during the examination of shallow lake Solyonoe situated at the territory of Omsk. Large resources of the raw biomass of spirulina in summer make it possible to use the lake as a source of valuable biological raw material.

Complexes of microscopic fungi of seven polliniferous species at an apiary in the Zalesovo District of the Altay Territory were studied during two years with different weather conditions. A comparative analysis of fungal cenoses of vegetative, generative organs and pollent grains of plants was carried out.

The human selenium status in 32 districts of Omsk region was determined, serum selenium being in the range 73-116 µg/L. An indirect correlation was found between serum selenium concentrations and whole mortality, malignаncy from lung cancer, ovarian cancer and rectal cancer. Significant differences in selenium accumulation coefficient in plants were shown to depend on the type of soil. Methods of the human selenium status optimization are discussed.

Results of the investigation of qualitative composition and relative concentrations of readily volatile compounds of needles in two natural pine populations situated in the forest-steppe zone in the south of Middle Siberia are presented. The number of components distinguished is 89. Anаlysis of intra- and interpopulation variability of 31 terpenoids (of mono- and sesquiterpene fractions) was carried out. The spatial structure of the dispersion of signs was anаlyzed. Reliable interpopulation differences in the concentrations of the majority of compounds were marked. It was established that worsening of growth conditions inside populations causes an increase in the mass concentration of light-weight monoterpene compounds, especially α-pinene, a decrease in the qualitative diversity of the components of volatile oils. Groups of terpenoids with relative content connected to different extents with interpopulation differences and diversity of conditions for tree growth inside populations were distinguished.

The dynаmics of damage and litter of the needles of pine Pinus sylvestris (L.) and spruce Picea obovata Ledeb.  P. abies (L.) Karst. in the basin of the Northern Dvina under atmospheric pollution was studied. Correlations of morphometric parameters of the assimilation apparatus with the distance to the source of emissions and concentrations of pollutants in the air, snow, soil, and heavy metals in needles were revealed.

The influence of PC "Mondi Syktyvkar Timber Industry Complex" on the chemical composition of pine needles was studied. Comparative anаlysis of the mineral composition of pine needles showed that the age dynamics of the concentrations of the majority of elements under investigation for the background region and for the zone affected by emissions have common trends. The total content of chemical elements in bilberry pine forests did not differ over the needle age or over the distance from the pollution source. Examination carried out in 2007 revealed that the total concentration of elements in the one-year needles of pine is higher than that in the needles of older ages. During the period of studies, a decrease in pine needle mineralization was observed under the conditions of pollution in comparison with the background territory. Under the aerotechnogenic emissions of nitrogen and sulfur oxides, carbon compounds, their accumulation in pine needles was not detected (except for the impacted region at 1.3 km).

In the region of the Middle Urals copper smelting plant, in two contrast zones of atmospheric pollution we evaluated the dimensional and reproductive characteristics of the thalli of epiphytic lichen Hypogymnia physodes (L.) Nyl. and determined the concentrations of heavy metals (Cu, Fe, Cd, Zn, Pb) in them. The nonuniformity of populations both over the dimensional and reproductive characteristics and over metal content was demonstrated. The high heterogeneity of subpopulations growing on different photophytes was discovered. It is recommended to optimise data collection by taking the samples from a large number of trees (20-30) with smaller number of thalli (10-20) from one photophyte.

Biomass of epiphytic lichens on Pinus sylvestris varies from 130 to 1090 g. The major biomass is comprised by the lichens of three genera: Bryoria (45 %), Hypogymnia (34 %) and Evernia (12 %). The majority of lichens are located on tree branches (96 %) in the zone of maximal development (at the height of 9-13.5 m) (66 %). The biomass of lichens on tree trunks is insignificant (4 %) and is concentrated by 70 % at the trunk bases.

Basing on the concept of the effect of landscape structure on the water regime of territory and on the space survey data for the basins of rivers on the northern macro-slope of West Sayan, the landscape hydrogeological classification of natural complexes was made and evaluation of their hydrogeological functions was carried out. At the background of general altitudinаl belt regularities, local features of the distribution of water balance characteristics were revealed.

Possibility to construct the growth class scale for Pinus sylvestris on the basis of the data on the course of growth of separate trunks with maximal height was analyzed. Two principles of the classification of tree stands over growth course are discussed: 1) over the parameters of Mitscherlich function - b₁(upper limit), b₂ (slope), b₃(shape), 2) over the inflection of the curve of tree elongation (h_m is the height at the moment of maximal apical growth rate, t_m is the age of achievement of the maximal apical growth rate).

Sexual systems and the associations with several ecological and life history attributes were examined for 977 native angiosperms of subclass Rosidae in Siberia. The majority of angiosperms in Siberia are hermaphrodites (87,7 %, N = 857). The most widespread forms of sexual differentiation are andromonoecy, gynodioecy and dioecy. The rarest forms of sexual differentiation are monoecy, trioecy and androdioecy. Seven of the 34 families are the richest in species with sexual differentiation: Aceraceae, Elaeagnаceae, Haloragaceae, Rhamnаceae, Diрsacaceae, Apiaceae, Geraniaceae.

Ecological evolution of the species of ebracteatae section of Typha L. genus since eozen is proposed. Typha and Engleria (Leonova) Tzvel. sections were formed in different geological periods and in different regions of Eurasia. The bloom of section Typha contacts the Poltava flora, while section Engleria was formed under the severe conditions of Arcto-Tertiary flora of East Siberia. A noticeable role in the ecological evolution of the sections was played by the West Siberian Sea.
Taxonomic variety and the sizes of areas of the investigated sections, with cold snаps outlined in Pliocene, came to the end in Pleistocene with depletion and insularization. The tendency to convergence in the evolution of the sections of Typha genus was outlined in Holocene.