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1.
E. V. Lapygina L. V. Lysak E. A. Bakulina D. G. Zvyagintsev 《Eurasian Soil Science》2006,39(11):1228-1232
It was determined that bacteria in soils are characterized by a high resistance to short (1 day) treatments with saturated solutions of mineral salts, 96% ethanol, 1 N HCl, and 1 N NaOH. The soil treatment with acid and alkali did not cause any significant decrease of the bacteria number (staining with acridine orange) in the studied samples of alluvial meadow soil and ordinary chernozem; a significant amount of cells (10 to 30%) preserved the undisturbed structure of their DNA. The shock effects of the saturated salt solutions and ethanol on the bacteria were much weaker as compared with the acid and alkali treatments: 60 to 90% of the cells preserved an undisturbed structure of their DNA. The biocide treatments had significant effects on the number of saprotrophic bacteria grown on a glucose-peptone-yeast medium and manifested themselves in a decrease of the amount and taxonomic diversity, as well as in the essential rearrangement of the structure, of the saprotrophic bacterial complex: the absolute domination of bacilli and almost complete inhibiting of Gram-negative bacteria were observed. The proteobacteria and cytophagous bacteria appeared to be most sensitive to the biocide soil treatments; the bacteria of the actinomycetic line and bacilli were less sensitive. The cells resistant to the applied treatments were almost always found among the representatives of the Arthrobacter, Rhodococcus, Micrococcus, Myxococcus, and Polyangium genera. 相似文献
2.
Nikitin D. A. Lysak L. V. Mergelov N. S. Dolgikh A. V. Zazovskaya E. P. Goryachkin S. V. 《Eurasian Soil Science》2020,53(4):467-484
Eurasian Soil Science - The biomass of prokaryotes and fungi, organic carbon stocks, and CO2 emission were studied in the Cryosols and Leptosols of Franz Josef Land. The highest carbon stocks were... 相似文献
3.
Eurasian Soil Science - The results of experiments on possible reduction of soil allelotoxicity level for grain crops are presented. It was found that autoclaving of soils significantly reduces... 相似文献
4.
Urbanozems (Urbic Technosols) contaminated by heavy metals and polychlorbiphenyls (Urbic Technosols Toxic) and intruzems (Urbic Technosols Toxic) were studied in Moscow; additionally, we studied recreazems (Urbic Technosols Thaptohumic) and culturozems (Urbic Technosols Pantohumic) on the territory of the Botanical Garden of Moscow State University (Aptekarskii Ogorod, the Apothecaries’ Garden). In the soils contaminated with heavy metals and oil products, the number of viable cells of bacteria decreased, whereas the content of filterable forms of bacteria increased. The taxonomic structure of saprotrophic bacterial complexes in contaminated urban soils was transformed towards an increase in the diversity of bacterial taxa atypical of natural undisturbed soils. Rhodococci (Rhodococcus genus) predominated in the soils contaminated with oil and polychlorbiphenyls, enterobacteria (Escherichia, Enterobacter, and Klebsiella genera) predominated in the soils contaminated with municipal wastes, and Arthrobacter genus was dominant in the soils contaminated with cement dust. Soils of both Botanical Gardens of Moscow State University were characterized by the high population density and specific distribution of bacteria in the profile; the structure of their saprotrophic bacterial complex had some similarity with that in the soils of more southern regions. The obtained data on the bacterial diversity of urban soils attest to considerable transformation of bacterial communities both in the contaminated urban soils and in the soils of botanical gardens. 相似文献
5.
The population density, physiological state, and taxonomic composition of bacterial nanoforms were first studied in soils
of Russia. It was demonstrated with the help of fluorescent microscopy that the populations of nanoforms in the studied soils
are very high and comprise tens and hundreds of millions of cells per 1 g of soil. The portion of cells with undamaged cell
membranes was significantly higher in the nanoforms (95–98%) than in the cells of common size (about 50%), and this fact suggests
the viability of the nanoforms. The taxonomic diversity of the nanoforms is great; the representatives of the main phylogenetic
groups widespread in the soils were found among the nanoforms, namely, Archaea, Actinobacteria, Cytophaga, and Proteobacteria.
The results allow assuming that the transformation of the cells into nanoforms is a relatively common event in the life of
soil bacteria, allowing them to remain viable under unfavorable conditions and participate actively in soil processes. 相似文献
6.
The effect of bacterial-humus preparations on the biological activity of soils contaminated with diesel fuel was studied. The influence of the preparations was judged from the intensity of the CO2 emissions from the soil, the total number of bacteria, and the structure of the saprotrophic bacterial complex. The ability of bacterial-humus preparations to enhance the biological activity of contaminated soils was shown. The possibility of maintaining target populations of bacteria in the soil for at least two months was proved. 相似文献
7.
I. V. Chistyakov S. Ya. Trofimov L. V. Lysak A. A. Stepanov 《Moscow University Soil Science Bulletin》2013,68(1):48-52
By gel filtration on Sephadex G-50 and G-75, we investigated the changes in the composition and ratio of the molecular fractions of humic acids under the influence of native soil microbial complexes. The highest degree of decomposition of the initial humic acid was observed when ammonium nitrate was used as a source of additional energy in the mineral nutrient medium without a yeast extract. The appearance of a low molecular fraction of organic substances on chromatograms may be associated with the synthesis by bacteria of simple organic substances on the medium with humic acids as a single source of carbon. 相似文献
8.
L. V. Lysak M. S. Kadulin I. A. Konova E. V. Lapygina A. V. Ivanov D. G. Zvyagintsev 《Eurasian Soil Science》2013,46(6):668-675
It is shown for the first time that a significant part of the bacteria (up to 40%) in the iron-manganic concretions of soddy-podzolic and soddy meadow soils are represented by nanoforms; their number reaches 600–700 million cells/g. Judging from the specific luminescent coloration, the fraction of viable cells among the bacterial nanoforms is very high in the concretions and amounts up to 88–99%. For the first time, the following phyla were identified among the bacterial nanoforms in the concretions with the use of the FISH method: Alphaproteobacteria, Betaproteobacteria, Gammaproteobateria, Deltaproteobacteria, Acidobacteria, and Planctomycetes. The Gammaproteobacteria phylum predominated in the concretions from the soddy-podzolic soil, and the Deltaproteobacteria phylum predominated in the concretions from the soddy meadow soil. In the alluvial meadow soil, the Alphaproteobacteria, Betaproteobacteria, and Acidobacteria phyla were found. The significant number and portion of bacterial nanoforms in the concretions, their high vitality, and their taxonomic diversity allow us to conclude that the bacterial nanoforms play an important role in the processes taking place in the concretions. 相似文献
9.
I. G. Shirokikh G. M. Zenova O. V. Merzaeva E. V. Lapygina G. A. Batalova L. V. Lysak 《Eurasian Soil Science》2007,40(2):158-162
The bacterial population, the length of the actinomycetal mycelium, the total biomass of prokaryotes, and the taxonomic composition of mycelial prokaryotes have been determined in the rhizosphere of hullless and chaffy subspecies of oats (Avena sativa L.) grown in a field experiment on a soddy-podzolic soil. The antifungal potential of actinomycetes associated with the roots of chaffy and naked (hull-less) oats have been compared. 相似文献
10.
T. A. Sokolova I. I. Tolpeshta L. V. Lysak T. S. Chalova 《Moscow University Soil Science Bulletin》2015,70(4):139-146
The total number of bacteria, the length of the fungal mycelium, and some chemical properties are evaluated in the rhizosphere of fir (Picea abies) trees and out of the rhizosphere zone in the AEL horizon of podzolic soil in the Central Forest State Nature Biosphere Reserve (CFSNBR). In the rhizosphere soil, the total number of bacteria is found to be 1.5 times greater and the fungal mycelium length two times greater than in the soil outside of the rhizosphere. The rhizosphere soil is characterized by consistently higher content of C org in the whole soil and in the clay and fine silt fractions due to the increase in microbial biomass and the continuous supply of organic substances from dead cells and root exudates. The rhizosphere soil has consistently lower values of pH in water and salt extracts and higher values of exchangeable acidity because of the more active functioning of soil biota and the input of protons with root exudates. The content of exchangeable potassium in the rhizosphere is higher than in the nonrhizosphere soil. This difference can be explained by the increase in potassium mobility in the illite–expandable minerals buffer system under more acid conditions and more active functioning of biota. 相似文献