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1.
The contents of fungal mycelium have been studied in paleosols of ancient archeological monuments and in surface soils within the steppe, dry steppe, and desert zones of European Russia, on the Stavropol, Privolzhskaya, and Ergeni uplands. The buried paleosols date back to the Bronze Age (4600–4500 and 4000–3900 BP), the Early Iron Age (1900–1800 BP), and the early 18th century (1719–1721). The fungal mycelium has been found in all these paleosols. The biomass of fungal mycelium varies from 2 to 124 μg/g of soil. The distribution patterns of fungal mycelium in the profiles of buried paleosols and surface soils have been identified. It is shown that the dark-colored mycelium is typical of the ancient paleosols. In some cases, the content of the dark-colored mycelium in them may reach 100% of the total mycelium biomass. 相似文献
2.
Adriani O Barbarino GC Bazilevskaya GA Bellotti R Boezio M Bogomolov EA Bonechi L Bongi M Bonvicini V Borisov S Bottai S Bruno A Cafagna F Campana D Carbone R Carlson P Casolino M Castellini G Consiglio L De Pascale MP De Santis C De Simone N Di Felice V Galper AM Gillard W Grishantseva L Jerse G Karelin AV Koldashov SV Krutkov SY Kvashnin AN Leonov A Malakhov V Malvezzi V Marcelli L Mayorov AG Menn W Mikhailov VV Mocchiutti E Monaco A Mori N Nikonov N Osteria G Palma F Papini P Pearce M 《Science (New York, N.Y.)》2011,332(6025):69-72
Protons and helium nuclei are the most abundant components of the cosmic radiation. Precise measurements of their fluxes are needed to understand the acceleration and subsequent propagation of cosmic rays in our Galaxy. We report precision measurements of the proton and helium spectra in the rigidity range 1 gigavolt to 1.2 teravolts performed by the satellite-borne experiment PAMELA (payload for antimatter matter exploration and light-nuclei astrophysics). We find that the spectral shapes of these two species are different and cannot be described well by a single power law. These data challenge the current paradigm of cosmic-ray acceleration in supernova remnants followed by diffusive propagation in the Galaxy. More complex processes of acceleration and propagation of cosmic rays are required to explain the spectral structures observed in our data. 相似文献
3.
B. A. Borisov L. A. Pozdnyakov O. V. Selitskaya L. I. Tribis 《Moscow University Soil Science Bulletin》2016,71(3):109-112
Effect of inoculation of plants by mycorhiza-forming fungus Glomus intraradices on nickel and copper phytoextraction from soddy-podzolic soil has been studied. The soil was intentionally contaminated by these elements. Mycorhization may cause both a rise and a drop in the content of the elements in the above ground parts of plants. It is shown that inoculation of plants by mycorhiza-forming fungus by its application to the soil at seeding does not result in the destabilization of microbe cenoses in the variants with application of heavy metals and in control variants. 相似文献
4.
A. O. Alekseev T. V. Alekseeva M. Hajnos Z. Sokolowska P. I. Kalinin A. V. Borisov 《Eurasian Soil Science》2008,41(13):1424-1432
This work presents the results of a study of changes in the soil mineral components and the related modifications of the chemical
composition and surface properties of soils in the desert-steppe zone in the southern part of the Ergeni Upland. Burial mounds
dating back to the Bronze epoch have been investigated. According to radiocarbon data, their ages are estimated at 5100 ±
50, 4410 ± 100, 4260 ± 120, 4120 ± 70, and 3960 ± 40 years. The substantial transformation of the clay minerals, the molar
chemical coefficients, the magnetic mineralogy, and the surface properties of the soils permits us to assess the rates of
the mineralogical transformations caused by the climate change during the time interval of less than <∼100 years. The ratio
between the content of the mineral phases in the buried soils of different ages testifies to the primary importance of climatic
factor in comparison with the total duration of weathering or the soil existence on the land surface prior to its burial,
i.e., the soil age. 相似文献
5.
The structural state of modern and buried chestnut soils on the Privolzhskaya Upland (Volgograd oblast) was studied in order to determine changes in the soil structure in dependence on the time of soil burying. The soils buried 3500, 1700, and 700 years ago and modern background chestnut soils were examined. The structural state of soils was determined via their fractionation on a set of sieves (10–0.25 mm) in the air-dry state. We determined the contents of coarse aggregates, total aggregates, disperse soil matter, aggregation coefficient, and the degree of differentiation of the soil profiles. It was found that the structure of buried soils is preserved for 3500 years after the soil burying. The structural state of the studied soils changed with time depending on the climatic conditions that existed at the moment of soil burying. In humid periods, the amount of coarse aggregates (lumps) decreased, and the content of aggregated fractions increased; the reverse processes took place in arid epochs. Thus, it was shown that the aggregate composition of soils is specific for each period of soil formation and depends on the degree of climatic humidity. It is preserved in the buried soils independently on the duration of their existence in the buried state. We determined the impact of aggregate size on the Corg tolerance toward mineralization processes. It was shown that the content of organic carbon and its physical protection from mineralization are determined by different mechanisms of its fixing in aggregates of different sizes and depend on the conditions for the development of soil structure before burying and on the duration of the soil existence in the buried state. The results obtained in this study can be used as a retrospective basis for predicting changes in the physical properties of soils under conditions of changing climate. 相似文献
6.
Ancient agricultural terraces in the Kislovodsk Depression: History and modern state of the soils 总被引：1，自引：0，他引：1
A. V. Borisov D. S. Korobov A. N. Simakova O. G. Zanina A. V. Bukhonov V. V. Demidov 《Eurasian Soil Science》2012,45(6):561-577
The results of the investigation into the history of soilscapes in the Kislovodsk Depression are discussed. It is shown that up to 60?C70% of the area of slopes and interfluvial plateaus at the heights of 900?C1500 m a.s.l. was terraced in the Late Bronze-Early Iron ages, during the Kobansk cultural stage (1200?C600 BC). Under these conditions, a sharp change in the climate with a considerable increase in the annual precipitation in the middle of the first millennium BC resulted in the activation of erosion and the formation of a layer of colluvial sediments overlying the buried soil on the terraces. Thus, the middle of the first millennium BC can be considered the zero moment for the modern stage of soil formation in the region. Problems of the current state of the terrace complexes and the development of erosion on them are also discussed. 相似文献
7.
Borisov A. V. Kashirskaya N. N. El’tsov M. V. Pinskoy V. N. Plekhanova L. N. Idrisov I. A. 《Eurasian Soil Science》2021,54(5):665-679
Eurasian Soil Science - The morphological and chemical properties and biological activity of soils on ancient agricultural terraces in the middle-high mountains of the Eastern Caucasus are... 相似文献
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V. A. Demkin A. V. Borisov T. S. Demkina T. E. Khomutova N. N. Kashirskaya 《Eurasian Soil Science》2010,43(13):1515-1526
On the basis of studies of subkurgan pedochronoseries, the main mechanisms of the development of soils of arid and desert
steppes in drained landscapes of the southeastern Russian plain in the Late Eneolithic and Bronze ages (6000−3000 years ago)
were established. During the fourth to third millennia BC, evolution of soils took place at the level of subtypes with a shift
of boundaries of soil subzones toward the north. In each of the studied natural regions (Central Russian Upland, Volga Upland,
Ergeni Hills, and Caspian Depression), an increase in the aridization of the climate in the second half of the third millennium
BC can be distinctly traced, owing to which a convergence of the topsoil with the transformation of dark-chestnut, chestnut,
and light-chestnut soils in chestnut-like semiarid soils, which dominated the region 4200–3900 years ago, occurred. In the
first half of the second millennium BC, another change in the conditions of soil formation occurred that was caused by an
increase in the degree of atmospheric humidity. It induced the divergence of the topsoil with a secondary formation of areas
of zonal chestnut soils and solonetzes in place of chestnut-like soils by the middle of the second millennium BC. The obtained
data gives reason to suggest that the age of modern chestnut solonetz complexes of the region does not exceed 3500 years. 相似文献