Статьи

ASSESSMENT OF THE IMPACT OF MAJOR LIMITING FACTORS ON THE GROWTH OF A VIMBA BREAM POPULATION (VIMBA VIMBA VIMBA) (CYPRINIDAE) - AN INTRODUCED SPECIES IN THE VOLGOGRAD RESERVOIR

An attempt was made to estimate the impact of major limiting factors on changes of the vimba population size in the Volgograd reservoir. The vimba population size in the reservoir is already close to its limit by one hypothesis, based on the accessibility of spawning area resources. A 15-fold increase in the vimba population size is possible for at least two decades by another hypothesis, providing for the population restriction by food resources.

ON THE SPECIFIC COMPOSITION, DISTRIBUTION AND ECOLOGY OF VOLES (MAMMALIA, CRICETIDAE, MICROTINA) IN THE NORTH-WESTERN CAUCASUS

Molecular-genetic typing was done for voles in the vicinity of the Pslukh forest station (the south of the Caucasus nature reserve), the Krasnaya Polyana, and the Utrish nature reserve (the Abrau peninsula). Based on the nucleotide sequence of the mitochondrial cytochrome b gene, the voles from the Krasnaya Polyana and Pslukh station were attributed to Robert’s snow vole (Chionomys roberti), whereas the animals from the Utrish nature reserve belong to the Eastern-European vole (Microtus rossiaemeridionalis).

ECOLOGICAL-PHYTOCENOTIC ASSESSMENT OF THE POPULATION STATUS OF THE RARE SPECIES DICTAMNUS GYMNOSTYLIS STEV. (RUTACEAE, MAGNOLIOPSIDA) IN THE SOUTHERN URALS

The results of our ecological-phytocenotic assessment of the natural coenopopulations of the rare (in Bashkortostan Republic) species Dictamnus gymnostylis Steven are given. In the Southern Urals, the species is on the northeastern border of its habitat. The ontogenetic, demographic and vitality structures of 20 coenopopulations were studied, the existence optima were found. The majority of the surveyed coenopopulations of D. gymnostylis have densities within 1 - 10 ind./sq.m and an incomplete ontogenetic spectrum, the basic ontogenetic spectrum being centered.

DYNAMICS OF THE ABUNDANCE AND DEMOGRAPHIC STRUCTURE OF POPULATIONS OF THE SMALL WOOD MOUSE (APODEMUS URALENSIS PALLAS, 1811) (RODENTIA, MURIDAE) AT URBANIZED SITES OF THE SOUTHERN TAIGA SUBZONE

The dynamics of abundance and demographic structure of the small wood mouse (Apodemus uralensis Pallas, 1811) at urbanized areas of a pine forest located within the urban limits and exposed to anthropogenic impact of various degree and character was under study during 9 years. No clear relation between the abundance dynamics and the sex ratio dynamics (age ignored) in the populations of A.

DYNAMICS OF THE ABUNDANCE AND COMMUNITY STRUCTURE OF SMALL MAMMALS IN THE SARATOV TRANS-VOLGA REGION

The population of small mammals in different areas of the Saratov Trans-Volga region features long-term and constantly increasing numbers of Sylvaemus uralensis, and its wide distribution in a variety of habitats. The maximum density of S. uralensis is 72.0 ind. per 100 trap-days and the fraction in catches is 73.0%. A tendency is observed to an increasing numbers of Microtus arvalis.

RESTORATION OF A BLACK-HEADED GULL (LARUS RIDIBUNDUS) (CHARADRIIFORMES, AVES) COLONY: THE ROLE OF RELEASERS IN THE FORMATION OF A NEW BIRD COLONY

Our study was conducted on the Kiyovo Lake situated within the limits of the town Lobnya (Moscow region). Formerly, the lake had held a large colony of the Black-headed Gull. Since 1996, these gulls ceased to breed at this lake. During 2009 - 2015, we managed to restore the colony by the usage of artificial measures.

INFLUENCE OF THE AGROCHEMICAL TREATMENT OF OIL-CONTAMINATED SOIL ON THE ABUNDANCE DYNAMICS OF MESOPHILIC AND PSYCHROPHILIC MICROORGANISMS

The influence of a polymeric structure-formation agent, chalk and microorganisms on the numbers of mesophilic and psychrophilic microorganisms in oil-contaminated soil was estimated. A carbamide-formaldehyde structure-formation agent had the most positive effect on microbial growth. Introducing hydrocarbon-degrading bacteria and chalk influenced to a lesser degree.

DEVELOPMENT OF THE SYSTEMATIC APPROACH TO STUDYING AGRICULTURAL LAND AND AGROLANDSCAPE MANAGEMENT

Methodological foundations of agrolandscape-environmental studies and management of agricultural land were developed. They are based on the concept of conservation and reproduction of land and other natural resources used in agriculture, soil fertility, the productive longevity of agro-ecosystems and agro-landscapes (All-Russian Williams Fodder Research Institute); the concept of the ecological frame of agricultural landscapes and ecologo-economic balance (Moscow State University, Institute of Geography Russian Academy of Sciences).

INFLUENCE OF NATURAL AND CLIMATIC FACTORS ON THE NUMBERS OF SAIGAS (SAIGA TATARICA PALL.) (BOVIDAE, ARTIODACTYLA) BETWEEN THE VOLGA AND URAL RIVERS

Characteristics of the Uralian saiga habitats are discussed. Periods of high and low abundance of the animals that alternate depending on the productivity of plant communities and territorial humidity (the number of watering-places) due to climate changes are shown. After the occurring periodic mass death of saigas, their population is quickly restored to its previous level, according to the existing feed and water resources.

PHYSIOLOGICAL AND BIOCHEMICAL ASPECTS OF HALOPHYTE ECOLOGY

Physiological and biochemical features of euhalophytes, сrinohalophytes and glycohalophytes growing in natural conditions in the Elton Lake area were studied. The water content in tissues, lipid peroxidation intensity, and membrane permeability were found to determine the differentiation of plants by their salt accumulation strategy. The concentration of pigments and their ratio are related to the mesostructure of leaves and dependent on the salt accumulation strategy and living form. The membrane complex is connected with the cell structure and photosynthetic apparatus.

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