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Analysis of the afforestation status in the arid conditions of Western Kazakhstan. – Àkhmedenov K. M. - The current status of the forest fund is considered, the agroforestry melioration potential of the Western Kazakhstan region is assessed. The modern silviculture stage on the area studied is described. The biodiversity depletion is noted, the possibilities of conservation of the existing natural and artificial protective plantings in the extreme conditions of the Western Kazakhstan region are assessed. Floodplain forests, chopping sand massifs and estuary-type depressions, gully and ravine forests are considered as key botanical and landscape territories of the surveyed area. Three key areas, namely: the experimental planting at the Dzhanybek research station, the aspen on the Bolshaya Ichka Mountain, and the Pershinsky forest are characterized. The necessity of applying new agroforestry land uses and practices is justified.
Key words: forest fund, forest cover, forest outposts, gully and ravine forests, àgroforestry melioration, floodplain forest, degradation.
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Reproductive biology of Cypripedium guttatum Sw. (Orchidaceae, Monocotyledones) at the northern border of its habitat. – Kirillova I. A., Pestov S. V., and Kirillov D. V. - The paper presents data on the reproductive biology of Cypripedium guttatum Sw. (Orchidaceae) in the Komi Republic, at the northern border of its habitat. Bees (Lasioglossum calceatum and L. brevicorne) are pollinators of C. guttatum in the region. The pollination efficiency is 21%. C. guttatum seeds are the largest ones among those of other orchid species in the region (1.11x0.22 mm). The size of seeds depends on the growing conditions of mother plants. The seed productivity of C. guttatum is rather high: every fruit contains 5 thousand seeds on the average, and more than 88% of them are of high quality. The seed crop is 2 – 22.6 thousand seeds per square meter.
Key words: Cypripedium guttatum, Orchidaceae, fruit, pollination, seeds, coenopopulation
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Viral infection of picocyanobacteriae in the Rybinsk reservoir during the freeze-up period. – Kopylov A. I., Kosolapov D. B., and Zabotkina E. A. - The virioplankton and planktonic picocyanobacteria abundances in the deep and shallow waters of the Rybinsk reservoir during the freeze-up period (the water temperature within 0.3 – 0.9°C) varied within (37.1 – 84.1)x106 ((57.3±2.1)x106 on the average) particles/ml and (13.5 – 75.0)x103 ((48.7±3.4)x103 on the average) cells/ml, respectively. The fraction of picocyanobacteria with viruses attached to their cell surface was 6.5 – 29.0% (12.0±0.8% on the average). The proportion of visible infected cells was 0.7 – 7.6% (2.2±0.3% on the average) of the numbers of picocyanobacteriae. Apparently, viruses play an important role in the picocyanobacteriae abundance regulation during the freeze-up period.
Key words: picocyanobacteria, virioplankton, virus-induced cyanobacteria mortality, freeze-up period, Rybinsk reservoir.
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Specific composition and abundance of the winter zooplankton in the Rybinsk reservoir. – Lazareva V. I. and Sokolova E. A. - The specific composition, seasonal dynamics, vertical and horizontal zooplankton distribution were studied in the pelagic zone and littoral of the Rybinsk reservoir in the winters of 2008 – 2016. The zooplankton abundance was found to be low (the abundance < 10,000 ind./m3, the biomass < 0.1 g/m3), by an order of magnitude lower than the values recorded in the 1970 – 1980s. As earlier, the abundance peak was observed in March. The cryophilic Cyclops kolensis prevailed among the crustaceans. A reproducing population of C. bohater (new for the reservoir) was recorded for the first time. The numbers of the previously abundant rotifers from the Notholca and Conochiloides natans genera decreased. They have been replaced by representatives of the Synchaeta genus (S. kitina and S. tremula) which formed ~50% (on the average) of the rotifer population under ice. The replacement of the under-ice zooplankton species and features of the phenology and dynamics of the Cyclops kolensis population are discussed.
Key words: Rybinsk reservoir, winter zooplankton, specific composition, dynamics, abundance distribution.
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Trophometabolic potential of Esenia fetida Savigny, 1826 (Oligochata, Lumbricidae) caused by copper nanoparticles and copper oxide in the soil. – Lebedev S. V., Sizova E. A., and Gavrish I. A. - Depending on the concentrations of Cu and CuO nanoparticles (NPs) (50, 100 and 500 mg/kg dry matter) introduced into an artificial soil, the influence of Cu NPs upon E. fetida is much stronger than similar CuO doses. In particular, this was reflected in higher mortality (80%) and a 50% weight reduction of the worm (p ≤ 0.05) when the dose of Cu NPs was 500 mg/kg, whereas the validity limit of the test (20%) was not exceeded with a similar dose of CuO. Copper hyperaccumulation in the body of E. fetida under the influence of Cu NPs was noted, while at exposure in a medium with CuO NPs, copper accumulated up to a level of 29 mg/kg with subsequent reduction. As to the activity of antioxidant enzymes, the rates of malondialdehyde , superoxide dismutase decreased and that of catalase increased. The enzymatic activity was quite opposite in the presence of CuO NPs.
Key words: Eisenia fetida, mortality, enzyme activity, accumulation rate, Cu uptake.
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Abundance of Tetrax tetrax L. 1758 (Otididae, Aves) in the Saratov region. – Oparin M. L., Kondratenkov I. A., Oparina O. S., and Mamayev A. B. - Based on the count data obtained by various methods and their statistical processing, the abundance of the autumn population of Tetrax tetrax in the Saratov Trans-Volga region was estimated from the late 1990s till now. From 2012 to 2016 it averaged about 30,000 individuals, and in the Right Volga Bank region it was one or two orders lower, the species’ distribution there was sporadic. When studying the T. tetrax abundance dynamics, an increase in its population on the studied territory in the first half of the 2000s was established. The necessity of carrying out count work in the future for monitoring the population is substantiated.
Key words: Tetrax tetrax, distribution, abundance, Saratov region.
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Percularities of hydrocarbon degradation by bacteria isolated from drill sludge. – Pleshakova Ye. V., Belyakov A. Yu., and Deev D. V. - Some microorganisms isolated from drill sludge (Bacillus circulans NSh, B. firmus OBR 1.1, B. firmus OBR 3.1, Solibacillus silvestris OBR 3.2, B. circulans OBR 3.3, Halomonas sp. OBR 1, and Erwinia rhapontici OBR 4.1) have been shown to be capable of degrading crude oil, mineral oil, and diesel fuel. It has been established that the B. circulans NSh and B. firmus OBR 1.1 bacteria degrade 62 and 32% of crude oil, respectively, in an alkaline medium (pH 9) for 14 days and degrade 42 and 22%, respectively, in a saline medium (10% NaCl). It was demonstrated that under high salinity and alkalinity conditions the B. circulans NSh and S. silvestris OBR 3.2 bacteria effectively degraded petroleum hydrocarbons not only solely but also in combination with the crude-oil-oxidizing Dietzia maris AM3 microorganism. The efficiency of crude oil degradation by the B. circulans NSh + D. maris AM3 association was higher than that by each monoculture.
Key words: drill sludge, petroleum hydrocarbons, microbial strains, degradation.
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Chemical signals of conspecifics and their role in the seasonal relationships in the Mongolian hamster (Allocricetulus curtatus) (Cricetinae, Rodentia). – Feoktistova N. Yu., Kropotkina M. V., and Kuznetsova E. V. - The hormonal response of males of the Allocricetulus curtatus hamster to the natural excreta (urine and midventral gland secretion [MVGS]) of conspecific females during several seasons of the year was studied when the animals were kept in the conditions of natural light and temperature. In the autumn, no significant changes in the testosterone level in the blood of males for any of the signals presented were observed. In the winter and summer, there was a trend of increasing this indicator in response to the smells of urine and MVGS of females in their diestrus state. In the spring, presentation of the urine of conspecific females in their estrous state led to a significant increase in the levels of both testosterone and cortisol, and the level of cortisol did not increase in response to exposure of the smells of females in their diestrus state in any season of the year. The level of progesterone significantly increased only when MVGS was presented in the spring and summer periods, and the absolute values of this indicator were significantly higher in the spring than in the summer. Differences in the responses to chemocommunication signals in two closely related Eversmann species (the Eversmann and Mongolian hamsters) are discussed in connection with intraspecific social relation peculiarities.
Key words: Allocricetulus curtatus, chemical signals, natural excreta, testosterone, progesterone, cortisol.
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Regularities of the ratio of the shell length to the individual weight of mollusks from the Dreissena genus (Dreissenidae, Bivalvia) in the Volgograd reservoir. – Filinova E. I., Kolozin V. A., and Malininà Y. À. - A regression analysis of the size and weight structure of the dreissenidae (D. bugensis and D. polymorpha) from the Volgograd reservoir was carried out. The power-dependence parameters in the resulting equation are different for the two mollusk species studied (W = 0.036L3.33 for D. bugensis and W = 0.064L3.32 for D. polymorpha). The established regression relationship between the individual body weight (W) and the mollusk’s shell length (L) has a high correlation degree: R2 = 0.96 for p = 0.01. Our results can be used for reconstruction of the individual mollusk weight from the shell length during trophological studies in the Lower-Volga reservoirs.
Key words: Volgograd reservoir, Dreissena, mollusks, regression analysis, shell length, individual weight.
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