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121.
A. V. Ivanov M. Braun D. G. Zamolodchikov D. V. Lynov E. V. Panfilova 《Eurasian Soil Science》2018,51(10):1164-1171
Forest litter as a component of the carbon cycle in pine–broadleaved forests of different ages was characterized. Field studies of the forest site of the Primorskaya State Agricultural Academy in the south of the Sikhote Alin Range continued for three years. Multiple sampling of forest litter and plant litter fall and measurements of the CO2 emission from the litter and underlying soil horizons were performed on test plots. The maximum litter pool (14.44 ± 0.86 t/ha) was found in the mature stand of Pinus koraiensis; the minimum litter pool (11.52 ± 0.65 t/ha), in the 80-year-old stand. The carbon stock in the litters amounted to 3.7% of the phytomass carbon. The rate of carbon turnover in the forest litters was relatively low in comparison with that in other regions: the ratio of carbon pools in the litter horizons and annual plant falloff reached 3.5. The winter season provided about 10–25% of the annual plant litter fall. The data obtained in this study describe a part of the carbon cycle and contribute to our understanding of the ecosystem function of climate regulation by valuable forest massifs in the south of the Far East of Russia. In this region, the decomposition of forest litters generates the CO2 flux amounting up to 16% of the total CO2 emission from the soil. 相似文献
122.
Current concepts of soil transformation and contamination in iron ore mining areas have been reviewed. Changes of soils and ecosystems in the mining areas are among the largest-scale impacts of economic activity on the nature. Regularities in the radial differentiation, spatial distribution, and accumulation of heavy metals in soils of different natural zones are analyzed. The effects of mining technogenesis and gas–dust emissions from enterprises on soil microbial communities and fauna are considered. In zones of longterm atmotechnogenic impact of mining and processing plants, the stable state of ecosystems is lost and/or a new technoecosystem different from the natural one, with own microbial cenosis, is formed, where communities of soil organisms are in the stress state. In the ore mining regions, embriozems are formed, which pass through specific stages of technogenically-determined development, as well as technosols, chemozems, and technogenic surface formations with variable material compositions and properties. Technogenic soils and soil-like bodies form a soil cover differing from the initial one, whose complexity and contrast are not related to the natural factors of differentiation. 相似文献
123.
Eurasian Soil Science - The development of tomographic studies of soil pore space in Russian soil science in 2011–2018 is discussed. In several years, these studies have evolved from the... 相似文献
124.
Mal’tsev K. A. Ivanov M. A. Sharifullin A. G. Golosov V. N. 《Eurasian Soil Science》2019,52(6):718-727
Eurasian Soil Science - Four river basins located in the forest, forest-steppe, and steppe zones of European Russia were evaluated for two time intervals (1960–1985 and 1986–2015) based... 相似文献
125.
N. G. Kovalev D. A. Ivanov V. A. Tyulin N. V. Grits S. I. Ageeva 《Russian Agricultural Sciences》2008,34(4):234-236
Yield formation of uneven-aged herbaceous stands under various weather and lanscape conditions is investigated in a multifactor experiment. It is shown that yield and adaptive properties of the stands depend in many respects on their age and climatic situation as well as on the properties of the landscape and soil environment. 相似文献
126.
Particle nucleation in the tropical boundary layer and its coupling to marine sulfur sources 总被引:1,自引:0,他引:1
AD Clarke D Davis VN Kapustin F Eisele G Chen I Paluch D Lenschow AR Bandy D Thornton K Moore L Mauldin D Tanner M Litchy MA Carroll J Collins G Albercook 《Science (New York, N.Y.)》1998,282(5386):89-92
New particle formation in a tropical marine boundary layer setting was characterized during NASA's Pacific Exploratory Mission-Tropics A program. It represents the clearest demonstration to date of aerosol nucleation and growth being linked to the natural marine sulfur cycle. This conclusion was based on real-time observations of dimethylsulfide, sulfur dioxide, sulfuric acid (gas), hydroxide, ozone, temperature, relative humidity, aerosol size and number distribution, and total aerosol surface area. Classic binary nucleation theory predicts no nucleation under the observed marine boundary layer conditions. 相似文献
127.
E. V. Krapivina D. V. Ivanov E. P. Vahchekin A. I. Albulov 《Russian Agricultural Sciences》2009,35(5):348-350
Subcutaneous injection of an aqueous chitosan succinate solution into heifer calves promotes an increase of the adaptation
reserve of absorption capacity of neutrophils 1 month after vaccination against leptospirosis, which creates the prerequisites
for a favorable state of the calves 2 months after vaccination. Injection of the preparation 3 days before vaccination is
found to be most effective. 相似文献
128.
Krasimir Ivanov Penka Zaprjanova Violina Angelova Stefan Krustev 《Communications in Soil Science and Plant Analysis》2019,50(7):878-893
Sample preparation is a crucial stage in obtaining correct results for micro- and macro-elements in soil and plants. The current study is a part of systematic research on the methods for soil and plant sample preparation for analysis of the most important macro-elements. The purpose is to determine the limits of the application of the most widely spread standardized and non-standardized methods for sample preparation and to shed more light on the possibilities of using scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS) and X-ray Diffraction (XRD) in soil and plant analysis. The most common methods for extracting macro- elements in soil and plants (dry ashing, acid digestion, and microwave digestion in different variants) were compared using three certified soil samples and the Polish reference material CTR-VTL-2 (Virginia tobacco leaves). Three macro-elements (K, Ca and Mg) in the digest were analyzed using flame AAS and the insoluble fraction after digestion were analysed using XRD and SEM-EDS. It is concluded, that the degree of extraction of the elements from soil and plant materials is highly dependent on the mineralisation method. The X-ray investigation showed the formation of KClO4 when HClO4 was used as a part of the acids mixture. The use of HF at Ca and Mg determination led to the formation of CaF2 and MgF2. The result was verified by SEM-EDS. 相似文献
129.
Irina Gladkikh Margarita Monastyrnaya Elena Zelepuga Oksana Sintsova Valentin Tabakmakher Oksana Gnedenko Alexis Ivanov Kuo-Feng Hua Emma Kozlovskaya 《Marine drugs》2015,13(10):6038-6063
Sea anemones are a rich source of Kunitz-type polypeptides that possess not only protease inhibitor activity, but also Kv channels toxicity, analgesic, antihistamine, and anti-inflammatory activities. Two Kunitz-type inhibitors belonging to a new Heteractis crispa RG (HCRG) polypeptide subfamily have been isolated from the sea anemone Heteractis crispa. The amino acid sequences of HCRG1 and HCRG2 identified using the Edman degradation method share up to 95% of their identity with the representatives of the HCGS polypeptide multigene subfamily derived from H. crispa cDNA. Polypeptides are characterized by positively charged Arg at the N-terminus as well as P1 Lys residue at their canonical binding loop, identical to those of bovine pancreatic trypsin inhibitor (BPTI). These polypeptides are shown by our current evidence to be more potent inhibitors of trypsin than the known representatives of the HCGS subfamily with P1Thr. The kinetic and thermodynamic characteristics of the intermolecular interactions between inhibitors and serine proteases were determined by the surface plasmon resonance (SPR) method. Residues functionally important for polypeptide binding to trypsin were revealed using molecular modeling methods. Furthermore, HCRG1 and HCRG2 possess anti-inflammatory activity, reducing tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) secretions, as well as proIL-1β expression in lipopolysaccharide (LPS)-activated macrophages. However, there was no effect on nitric oxide (NO) generation. 相似文献
130.
Vasil Georgiev Georgiev Jost Weber Eva-Maria Kneschke Petko Nedyalkov Denev Thomas Bley Atanas Ivanov Pavlov 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(2):105-111
Betalains are water-soluble plant pigments that are widely used as food colorants, and have a wide range of desirable biological
activities, including antioxidant, anti-inflammatory, hepatoprotective, anti-cancer properties. They can be produced from
various plants, notably beetroot, but betalain products obtained in this way also have some undesirable properties and are
difficult to standardize. A potentially attractive alternative is to use hairy root cultures. In the study reported here,
we found that betalain extracts obtained from hairy root cultures of the red beetroot B. vulgaris cv. Detroit Dark Red also had higher antioxidant activity than extracts obtained from mature beetroots: six-fold higher 2,2-dyphenyl-1-picrylhydrazyl
radical scavenging ability (90.7% inhibition, EC50 = 0.11 mg, vs 14.2% inhibition, EC50 = 0.70 mg) and 3.28-fold higher oxygen radical absorbance capacity (4,100 μM TE/g dry extract, vs 1,250 μM TE/g dry extract).
The high antioxidant activity of the hairy root extracts was associated with increased concentrations (more than 20-fold)
of total phenolic concomitant compounds, which may have synergistic effects with betalains. The presence of 4-hydroxybenzoic
acid, caffeic acid, catechin hydrate, and epicatechin were detected in both types of extract, but at different concentrations.
Rutin was only present at high concentration (1.096 mg.g−1 dry extract) in betalain extracts from the hairy root cultures, whereas chlorogenic acid was only detected at measurable
concentrations in extracts from intact plants. 相似文献