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Role of grassy plant communities in the formation of biogenic cycles of chemical elements. – Bezel V.S. and Zhuikova T.V. – The role of environmental factors in the formation of the biogenic cycles of chemical elements was studied. Under background conditions and chemical pollution, such biogeochemical and biocenosic factors as the specific composition of a community and the specific nature of chemical element accumulation, the biomass of individual species, and the productivity of phytocenosis play a significant role. The determinant factor for chemical element accumulation in the plant biomass is not the direct toxic influence of increasing concentrations of elements in soils but the chemical environmental degradation caused by it and manifesting itself as changes in the specific composition and decreasing the total phytocenosis biomass.
Key words: chemical elements, chemical environmental pollution, specific phytocenosis composition, productivity of communities, environmental factors.
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Flora adaptation in the Southern Volga Height to anthropogenic influence. – Berezutsky M.A. – Analyzed is the flora of all the basic types of anthropogenous biotops of the Southern Volga Height (within the Saratov region), namely, urbanized territories, technogenic places, artificial wood plantings, and agrocenoses. Of 1379 vascular plant species of the flora in the surveyed territory, only 908 ones are met on anthropogenous places. Among various types of anthropogenous places, the maximum (636) and minimum (438) numbers of species were revealed on technogenic sites and in agrocenoses, respectively. The structure of the flora's aboriginal fraction in the Southern Volga Height is hypothesized to have buffer properties and to be basically preserved even if 2/3 species would be lost.
Key words: flora, anthropogenic influence, adaptation, Saratov region.
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Influence of supreme water vegetation and filamentous seaweed on the succession of microperiphytic communities. – Bykova S.N., Borisovskaya E.V., and Vinogradov G.A. – The effect of some aquatic plants (Ceratophyllum demersum, Eleocharis acicularis, Elodea canadensis, Leptodictium riparium, and Mougeotia elegantula) on the succession of microperiphytic communities was studied in laboratory conditions. Both similarity and distinctive features in the formation of periphyton communities are shown. The dependence of the taxonomical diversity of communities on the physiological state of plants, their vital and postmortem excretion has been established.
Key words: microperiphyton, aquatic plants, succession of communities.
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Diatoms (Centrophyceae) in the Kama reservoir phytoplankton. – Genkal S.I. and Okhap-kin A.G. – On the basis of the results of our phytoplankton survey in the Lower-Kama and Votkinsk reservoirs, the species composition of diatoms (class Centrophyceae) has been determined. In the Lower-Kama reservoir, 20 species and varieties belonging to 8 genera (Aulacoseira Thwaites, Cyclostephanos Round, Cyclotella (Kutzing), Discostella Houk et Klee, Melosira Agardh, Sceletonema Greville, Stephanodiscus Ehrenberg, and Thalassiosira Cleve) were recorded for the first time. In the Votkinsk reservoir, 15 taxa of centric diatoms were found, of which 9 were new for the reservoir's flora, including representatives of the new genera Cyclostephanos and Thalassiosira. In view of our survey, 19 species from 9 genera (Aulacoseira, Cyclostephanos, Cyclotella, Discostella, Melosira, Puncticulata Hakansson, Sceletonema, Stephanodiscus, and Thalassiosira) were recorded in the reservoir.
Key words: diatoms, phytoplankton, Kama River, Lower-Kama and Votkinsk reservoirs.
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Biological peculiarities of xylotrophic basidiomycetes species in the forest-steppe of the Right-Volga-Bank region in situ and ex situ. – Il'ina G.V. and Lykov Yu.S. – The growth and development features of wood-destructive basidiomycetes prevalent in the Right-Volga-Bank forest-steppe were studied in natural conditions and in pure culture. The strains of parasitic species are characterized by low growth rates and an increased demand for easily accessible carbon sources. The strains of saprotrophic species, even those of different substrate origin, grow well in pure culture. The positive effect of extra sources of cellulose and lignin on the growth of saprotrophic strains was found.
Key words: xylotrophic basidiomycetes, pure culture, cellulose and lignin sources.
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Plankton of a highly-eutrophic lake under the influence of the vital activity products of a Grey Heron (Ardea cinerea L.) colony. – Kulakov D.V., Kosolapov D.B., Krylov A.V., Korneva L.G., Malin M.I., and Pavlov D.D. – The vital activity products of colonial grey herons (Ardea cinerea) promote structural changes in a planktonic organism community in the littoral zone of a highly-eutrophic lake. A number of signs specify an increase in the organic and nutrient loading in comparison with a background site and are similar to the changes observed under anthropogenic load. Some changes in the plankton community which are not usually observed under increased anthropogenic eutrophication are noted as well.
Key words: lake plankton community, species number, abundance, biomass, zoogenic impact.
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Parameters of productivity and biochemical composition of two species from Taraxacum L. growing in different vertical belts. – Mezhunts B.Kh., Navasardian M.A., and Sargsian T.A. – Peculiarities of leaf surface formation, dry matter accumulation and net productivity of photosynthesis in seasonal dynamics, and the content of photosynthetic pigments, bioenergy and organic matter in the flowering stage of dandelion (Taraxacum officinale Wiggers, 1780) growing in different vertical belts in the Geghama ridge (Armenia) were studied. Specific ecological conditions of these vertical belts inadequately influence the studied parameters of T. officinale. In particular, the plants in the meadow steppe zone attained their maximum indices of productivity and leaf surface much earlier than in the dry steppe zone. Some differences in other parameters of productivity, biochemical composition, and gross energy of dandelion (T. officinale) were revealed, although these variations had mostly irregular character and corresponded to no condition changes along the vertical belts. Results related to the content of organic matter and bioenergy in another dandelion (T. stevenii De Candolle, 1838) species widely spread in the alpine belt are presented as well.
Key words: Taraxacum, leaf surface, biomass, bioenergy, Geghama ridge, Armenia.
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Beaver (Castor fiber) usage mode of the Pra river plain reservoirs in the Oka nature reserve. – Pankova N.L. and Pankov A.B. – Specific features of the location of beaver settlements in the Pra river plain were studied. The beavers use 83% of all the plain waterbodies, 48% of which they employ for wintering. The beaver usage mode of waterbodies depends on the hydrological regime and composition of the water vegetation. Deep and macrophyte-rich river oxbows are heavily occupied by beavers and used by a beaver family all the year round. The beavers inhabiting the river stream or macrophyte-deficient reservoirs use several additional waterbodies besides their main location.
Key words: Beaver, plain reservoirs, water vegetation, Ryazan region, Russian Federation.
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Characteristics of vegetative communities with Hypericum perforatum L. in the Saratov region. – Parkhomenko V.M. and Kashin A.S. – 28 communities with Hypericum perforatum L. from five biotops in 17 districts of the Saratov region were surveyed. 325 vascular plant species (197 genera, 52 families) were revealed. In most communities the wood-edge and steppe species and those of anthropogenous biotops prevailed. On the southeast border of its habitat, H. perforatum behaves as an explerent by its ecological strategy. The places of its location are limited by the disturbance degree of the structure of communities rather than by the taxonomic composition of these communities.
Key words: Hypericum perforatum, community, floristic variety, abundance, vital forms, ecomorphs, cenomorphs.
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Comparative studies of the vegetative pigment content in the bottom sediments of the Gorky and Cheboksary reservoirs. – Sigareva L.Ye., Timofeeva N.A., and Zakonnov V.V. – The distribution of plant pigments and typological characteristics of the bottom sediments in two Volga reservoirs (the Gorky and Cheboksary ones) were studied. The vegetative pigment content was determined in several fractions with grain sizes > 0.1, 0.1 – 0.01, and < 0.01 mm. The differences in the plant pigment content agree with the horizontal distribution of the bottom sediments. A series of regression equations describing the dependence between the chlorophyll and pheopigment content and the properties of the bottom sediments was obtained. Peculiarities of the pigment distribution were found.
Key words: plant pigments, bottom sediments, Volga reservoirs.
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Effect of seed priming on germination and seedling growth of Festuca arundinacea Schreb and Agropyron desertorum (Fisch. ex Link) J.A. Schultes. – Tilaki Ghasem Ali Dianati, Behtari Behzad, Alizadeh Mohammad Ali, and Jafari Ali Ashraf – A study was made on two major forage plants Festuca arundinacea Schreb and Agropyron desertorum (Fisch. ex Link) J.A. Schultes in laboratory conditions. Hydropriming (distilled water) and osmopriming (KNO3, PEG-6000) were used in the study to prime seeds. The results indicated that priming improved the germination percentage, mean germination time, uniformity, and vigor index in F. arundinace. None of the priming treatments tested showed a beneficial effect on A. desertorum, but its primed seeds enhanced the mean of shoot and root length, and fresh weight seedling of the treated seeds. This study suggests that PEG (2.2 MPa) with 1-day duration is the most suitable seed priming to improve the germination percentage, uniformity, and vigor index, especially in F. arundinace. In addition, 3-day priming with KNO3 (2.2 MPa) is recommended as the best one to enhance the mean shoot and root length, and fresh weight seedling of treated seeds.
Key words: Festuca arundinacea, Agropyron desertorum, hydropriming, osmopriming, germination.
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First breeding records of Black Redstart Phoenicurus ochruros (S.G. Gmelin, 1774) in St. Petersburg. – Iovchenko N.P. and Zanin S.L. – Black Redstart Phoenicurus ochruros has been found in the Leningrad region since 1984, mainly during its seasonal migrations. In 2008 – 2009, two first (for the region) nests were found in St. Petersburg City (59°49'N, 30°04'E). This is the north-easternmost confirmed breeding place in the North-Western Russia. In the breeding season, the species favors overgrown areas with abandoned farms, factories, and other old or unfinished buildings. Lately, it has started to use the urbanized landscape.
Key words: Phoenicurus ochruros, expansion, breeding records, habitats, Leningrad region.
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Furca structure as a sign to provide Carabus granulatus' ability to flying. – Kolbachev L.E. – Properties of the Carabus granulatus furca texture are considered. Features enabling insects to fly are listed. With an example of C. granulatus, the relation between the furca structure and species ecology is shown.
Key words: Carabus granulatus, furca, flying, morphoecology.
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