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1.
The influence of regulatory forest policy tools on biodiversity measures for forests in Ukraine 总被引：1，自引：0，他引：1
The transition from a state-oriented forest economy to a market-oriented one requires a critical analysis of the set of tools designed to implement state forest policies. One of the important goals of Ukrainian forest policy is conservation of the biodiversity of forest ecosystems. This paper analyzes the influence of two of the regulatory forest policy instruments (zoning and prohibition of final harvesting) on the diversity of woody vegetation using Tobit regression. Data on the forest resources of the Sumy administrative province in Ukraine are used for the analysis. Additionally, we look at how diversity of woody vegetation is affected by the form of forest tenure. 相似文献
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E. N. Baranova A. A. Gulevich V. Yu. Polyakov P. N. Kharchenko 《Russian Agricultural Sciences》2007,33(4):236-238
The anatomic structure of cotyledons of clone 124 and cultivar Nadezhda during germination in various isosmotic sodium chloride and mannitol concentrations is compared. The possibility of using a quantitative method for revealing the character of salt tolerance in plants obtained by biotechnological methods is shown. 相似文献
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E. N. Baranova A. V. Bakulina I. G. Shirokikh O. N. Shuplechova I. A. Chaban A. A. Gulevich V. Y. Polyakov 《Russian Agricultural Sciences》2011,37(5):358-363
The structural organization of roots, induced in the callus cultures of barley genotypes differing in aluminum tolerance:
cv Kupetz, cv 999-93 and its somaclonal form R 999-93 was studied. The goal of this research was to determine how the toxic
effects of aluminum at low pH affects the structure of the root and any cells damage of different tissues meristematic zone.
At pH 5.8–6.0 root callus from different genotypes had specific features, manifested in the structure root cap, the epidermis,
the form of roots. In the presence of 40 mg/1 Al3+ ions and pH 3.7–3.8 in the roots, callus was obtained from the cv Kupetz, there is strong damage to the epidermis, root cap
and some other tissues, which, although and resulted in the death of cells, however, were not lethal character. In roots,
callus derived from varieties 999-93, under the influence Al3+ ions was observed irreversible changes that lead either to compaction cytoplasm and nuclei, especially in the central part
of the root or to the plasmolysis and the destruction of cells, especially in the meristematic zone. On transverse sections
was found damaged cells of the central part of the root, formation of the densified outer cell wall of epidermal cells. At
the investigation of R 999-93 callus roots it was be shown that most of the cells of meristematic zone of root retained their
viability at influence of Al3+ ions. So, the somaclon from cv 999-93, obtained earlier in callus culture by selection on Al-tolerance,
differs from the original form at the level of mesostructure. 相似文献
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Tatiana A. Sorkina Alexander Yu. Polyakov Natalia A. Kulikova Anastasia E. Goldt Olga I. Philippova Alina A. Aseeva Alexey A. Veligzhanin Yan V. Zubavichus Denis A. Pankratov Eugene A. Goodilin Irina V. Perminova 《Journal of Soils and Sediments》2014,14(2):261-268
Purpose
Humic substances (HS) being natural polyelectrolyte macromolecules with complex and disordered molecular structures are a key component of the terrestrial ecosystem. They have remarkable influence on environmental behavior of iron, the essential nutrient for plants. They might be considered as environmental friendly iron deficiency correctors free of synthetic iron (III) chelates disadvantages. The main goal of this study was to obtain water-soluble iron-rich humic compounds (IRHCs) and to evaluate their efficiency as chlorosis correctors.Materials and methods
A facile preparation technique of IRHCs based on low-cost and available parent material was developed. The iron-containing precursor (ferrous sulfate) was added dropwisely into alkaline potassium humate solution under vigorous stirring and pH-control. A detailed characterization both of organic and inorganic parts of the compounds was provided, the iron species identification was carried out jointly by EXAFS and Mössbauer spectroscopy. Bioassay experiments were performed using cucumber Cucumis sativus L. as target plants. Plants were grown in modified Hoagland nutrient solution, prepared on deionized water and containing iron in the form of IRHCs. Total iron content in dry plants measured by spectrophotometry after oxidative digestion and the chlorophyll a content determined after acetone extraction from fresh plant were used as parameters illustrating plants functional status under iron deficiency condition.Results and discussion
The high solubility (up to130 g/l) and iron content (about 11 wt%) of the IRHCs obtained allow considering them to be perspective for practical applications. A set of analytical methods has shown that the main iron species in IRHCs are finely dispersed iron (III) oxide and hydroxide nanoparticles. An application of the precursor solution acidification allows to obtain compounds containing a significant part of total iron (up to 30 %) in the form of partly disordered iron (II–III) hydroxysulphate green rust GR(SO4 2?). Bioavailability of iron from IRHCs was demonstrated using bioassay in cucumber plants grown up on hydroponics under iron deficiency conditions.Conclusions
The application of iron oxides chemistry for humic substance containing solution was proved to be an effective approach to synthesis of IRHCs. Using bioassay on cucumber plants C. sativus L. under iron deficiency conditions, the efficiency of compounds obtained as chlorosis correctors was demonstrated. Application of water-soluble IRHCs led to significant increase of chlorophyll a content (up to 415 % of the blank) and iron content in plants (up to 364 % of the blank) grown up on hydroponics. 相似文献7.
Polyakov D. G. Arkhangelskaya T. A. Ryabukha A. G. Kovda I. V. 《Eurasian Soil Science》2021,54(9):1328-1336
Eurasian Soil Science - Thermal diffusivity of the cryomorphic soils formed on limestone in the Orenburg oblast (Russia) has been studied. Soils are identified as cryomorphic basing on the... 相似文献
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Eurasian Soil Science - Development of carbon polygons for monitoring the emission and deposition of carbon compounds in terrestrial ecosystems is one of the priority tasks in the case of climate... 相似文献
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The results of investigating third-generation matrix silicon solar cells with an efficiency of more than 25% during conversion
of concentrated solar radiation are given. Electrical and optical characteristics are discussed. Modern technologies of semiconductor
electronics and nanotechnology will soon allow increasing the efficiency of matrix silicon solar cells to 40%. 相似文献
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Polyakov Maksym Rowles Alexei D. Radford James Q. Bennett Andrew F. Park Geoff Roberts Anna Pannell David 《Landscape Ecology》2013,28(2):329-341
Landscape Ecology - The removal, alteration and fragmentation of habitat are key causes of biodiversity decline worldwide. In Australia, temperate woodlands have been disproportionately cleared... 相似文献