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A. Yu. Lein A. S. Savvichev I. I. Rusanov G. A. Pavlova N. A. Belyaev K. Craine N. V. Pimenov M. V. Ivanov 《Lithology and Mineral Resources》2007,42(3):221-239
Study of biogeochemical processes in water and sediments of the Chukchi Sea in August 2004 revealed atypical maximums of the concentration of biogenic elements (N, P, and Si) and the rate of microbial sulfate reduction in the surface layer (0–3 cm) of marine sediments. The C: N: P ratio in the organic matter (OM) of this layer does not fit the Redfield-Richards stoichiometric model. Specific features of biogeochemical processes in sea are likely related to the complex dynamics of water, high primary productivity (110–1400 mg C/(m2 day)), low depth of basin (<50 m in 60% of the water area), reduced food chain due to low population of zooplankton, high density of zoobenthos (up to 4230 g m?2), and high activity of microbial processes. Drastic decrease in the concentration of biogenic elements, iodine, total alkalinity (Alk), and population of microorganisms beneath the 0–3 cm layer testify to a large-scale OM decay at the water-seafloor barrier. Our original experimental data support the high annual rate of OM mineralization at the bottom of the Chukchi Sea. 相似文献
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N. Pimenov A. Savvichev I. Rusanov A. Lein A. Egorov A. Gebruk L. Moskalev P. Vogt 《Geo-Marine Letters》1999,19(1-2):89-96
Box and gravity cores recovered from the Håkon Mosby mud volcano (HMMV) during cruise 15 of the R/V Professor Logachev were analyzed for bacterial activity and benthic fauna distribution. The high bacterium number (up to 9.6×109 cells cm-3 of the sediment) and marked rates of sulfate reduction (up to 0.155?mg?S?dm-3?day-1) and methane oxidation (up to 9.9?μg?C?dm-3?day-1) were shown for the upper horizons of the sediments of the HMMV peripheral zone. The benthic community is characterized by the presence of two pogonophoran species, Oligobrachia sp. and Sclerolinum sp., harboring symbiotic methanotrophic bacteria. 相似文献
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Vasiliev A. A. Melnikov V. P. Zadorozhnaia N. A. Oblogov G. E. Streletskaya I. D. Savvichev A. S. 《Doklady Earth Sciences》2022,505(1):506-511
Doklady Earth Sciences - The results of studying the emission, content, and isotopic composition of methane in soils of the active layer in the zones of typical and southern shrubby tundra of the... 相似文献
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Kravchishina M. D. Klyuvitkin A. A. Volodin V. D. Glukhovets D. I. Dubinina E. O. Kruglinskii I. A. Kudryavtseva E. A. Matul A. G. Novichkova E. A. Politova N. V. Savvichev A. S. Silkin V. A. Starodymova D. P. 《Oceanology》2022,62(4):572-574
Oceanology - Research regarding the conditions and processes of paleo- and modern sedimentation with an assessment of particles and pollution fluxes, with determination of the rates of... 相似文献
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Seasonal biogeochemical and microbiological studies of small lakes in taiga zone of northwestern Russian (Arkhangelsk Province) 总被引：1，自引：0，他引：1
N. M. Kokryatskaya S. A. Zabelina A. S. Savvichev O. Yu. Moreva T. Ya. Vorobjeva 《Water Resources》2012,39(1):105-117
The results of biogeochemical and microbiological studies of three small lakes in southwestern Arkhangelsk province are presented.
The lakes differ in their morphometric characteristics, thermal and oxygen regimes, and the extent of anthropogenic impact
they experience. In the periods of summer and winter stratification, anaerobic water layers with higher phosphates, ammonium,
and sulfide sulfur (hydrogen sulfide) are found to form in the bottom horizon of deep-water zones of the lakes. The highest
concentrations of sulfide sulfur (150–210 μg dm−3) were recorded in the shallow Beloe Lake during winter low-water period, while in summer, sulfide concentration did not differ
from those obtained in other lakes (∼10 μg dm−3). The abundance of sulfate-reducing bacteria in lake bottom sediments varied from 10 to 100000 cell cm−3, and the rate of sulfate reduction process varied from 29 to 3746 μg S dm−3 day−1. Seasonal variations were revealed in hydrogen sulfide distribution over the water column and in the rate of sulfate reduction
process in the upper horizons of bottom sediments in the examined lakes. 相似文献
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M. D. Kravchishina A. Yu. Lein A. S. Savvichev L. E. Reykhard O. M. Dara M. V. Flint 《Oceanology》2017,57(1):174-191
Authigenic minerals were studied in Holocene shelf sediments of the Laptev Sea (cold methane seep site, water depth 71 m). The study presents the first finds of large hard carbonate concretions with Mg-calcite cement in recent sediments of the Arctic shelf seas. These concretions differ from previously reported glendonites and concretions from bottom sediments of the White Sea, Kara Sea, Sea of Okhotsk, etc. A study of the morphology, microstructure, and composition of these newly reported concretions revealed the multistage formation of carbonates (structural varieties of Mg-calcite and aragonite). It was shown that organic matter played an important role in the formation of authigenic carbonates, i.e., in the formation of sedimentary–diagenetic Mg-calcite. The role of methane as a possible source for authigenic carbonate formation was estimated. It was found that methane-derived Mg-calcite accounts for 17–35% of concretion materials. Mg-calcite had δ13С-Сcarb values between–24 and–23‰ and δ13С-Сorg values between–44.5 and–88.5‰. 相似文献