Electron paramagnetic resonance of phytofulgurite     

Izotov  V. G.  Mamin  G. V.  Orlinskii  S. B.  Silkin  N. I.  Sitdikov  D. T.  Sitdikova  L. M.  Salakhov  M. Kh.  Lysyuk  A. Yu.  Yushkin  N. P. 《Doklady Earth Sciences》2011,437(1):424-427

Doklady Earth Sciences -  相似文献   

Systems Research of Sedimentation in the European Arctic during the 84th Cruise of the Research Vessel Akademik Mstislav Keldysh     

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   

The phenomenon of bloom development of the invasive potentially toxic dinoflagellate <Emphasis Type="Italic">Gonyaulax polygramma</Emphasis> in deep water areas of the Caspian Sea     

L. A. Pautova  M. D. Kravchishina  V. A. Silkin  A. P. Lisitzin 《Doklady Earth Sciences》2017,474(2):657-661

This work presents the first data on the occurrence of the invasive, potentially toxic dinoflagellate Gonyaulax polygramma in the composition of plankton phytocenoses in the Caspian Sea. It was revealed that G. polygramma plays the key role in the quantitative characteristics of summer plankton phytocenoses and its bloom during the summer seasons of 2010 and 2013 was comparable in biomass (15–16 g/m³) to a “red tide.” In addition, the correlation between the G. polygramma bloom and the wind upwelling system in the eastern mid-Caspian region was established. For the first time, it is suggested that “bloom” of G. polygramma can also occur in deep-water halistatic areas (Derbent depression), remote from the upwelling system.  相似文献   

Structure of plankton phytocoenoses in the shelf waters of the northeastern Black Sea during the <Emphasis Type="Italic">Emiliania huxleyi</Emphasis> bloom in 2002–2005     

L. A. Pautova  A. S. Mikaelyan  V. A. Silkin 《Oceanology》2007,47(3):377-385

It is shown that, in 2002–2005, the mass development of the coccolithofore Emiliania huxleyi on the Gelendzhik shelf occurred annually and in May–June its abundance reached 1.5 × 10⁶ cells/l. In 2004–2005, the bloom of E. huxleyi was accompanied by a mass development of the diatom alga Chaetoceros subtilis var. abnormis f. simplex (0.6–0.9 × 10⁶ cells/l); for the first time, it was registered as a dominating form of the Black Sea phytoplankton. Small flagellates and picoplankton algae played a noticeable role in the phytoplankton throughout the entire period of the studies. Meanwhile, in the early summer period, the bulk of the biomass consisted of coccolithophores (50–60%), while, in the late summer period, diatomaceous algae dominated (50–70%). Among the ecological factors that favor the coccolithophore development one may note the microstratification of the upper mixed layer at a high illumination level and high temperature in the surface waters (18–21°C). The terrigenous runoff during the rainy period had a negative effect on the E. huxleyi development, while storms dispersed the population over the upper mixed layer. The wind-induced near-shore upwelling stimulated the development of diatoms.  相似文献   

Pelagic Ecosystem of the Nansen Basin under the Influence of Variable Atlantic Water Inflow: The Mechanism Forming Diatom Bloom in the Marginal Ice Zone     

Pautova  L. A.  Silkin  V. A.  Kravchishina  M. D.  Yakubenko  V. G.  Kudryavtseva  E. A.  Klyuvitkin  A. A.  Lobkovsky  L. I. 《Doklady Earth Sciences》2021,499(1):590-594

Doklady Earth Sciences - Unique data were obtained on the abnormally high level of phytoplankton biomass (30 g m–3) in the marginal ice zone of the deep-water High Arctic (the Nansen Basin,...  相似文献   

Coccolithophorids in the Black Sea: Their interannual and long-term changes     

A. S. Mikaelyan  V. A. Silkin  L. A. Pautova 《Oceanology》2011,51(1):39-48

A five-year study of the interannual changes observed in May–June during the mass reproduction of coccolithophorids was carried out in the northeastern part of the Black Sea. The long-term dynamics were analyzed using the data on the phytoplankton collected during the last 40 years. The fraction of coccolithophorids represents either 20 or 60% of the total biomass of the algae and does not depend on either the previous winter conditions or the nitrogen content and the N: P ratio in the surface water layer. Our studies have revealed the dependency between the phosphate content and the size of the coccolythophorids’ fraction in the total phytoplankton biomass. The long-term population dynamics includes three periods. Until the mideighties, the coccolythophorid fraction in the Black Sea phytoplankton was insignificant (3%). The average biomass was equal to 8 μg/l. In the late eighties, the average biomass increased up to 106 μg/l. Since the midnineties, coccolythophorids often prevail in the number and mass among the other phytoplankton species. The general tendency for the growth of the coccolythophorid fraction in the phytoplankton cenoses coincides with the increase in the phosphate concentration in the near-surface water observed within the last 40 years. This fact corresponds to the experimental results, which demonstrate that the coccolythophorid development during May–June is phosphate-limited.  相似文献   

The Biological Calcium Carbonate Pump in the Norwegian and Barents Seas: Regulation Mechanisms     

Pautova  L. A.  Silkin  V. A.  Kravchishina  M. D.  Chultsova  A. L.  Lisitzin  A. P. 《Doklady Earth Sciences》2020,490(1):46-50

Doklady Earth Sciences - This paper reports on a study of the phytoplankton calcium carbonate pump in the Norwegian and Barents seas in July–August 2017. Coccolithophores, a unique marine...  相似文献   

Vertical distribution of suspended particulate matter in the Caspian Sea in early summer     

M. D. Kravchishina  A. Yu. Lein  L. A. Pautova  A. A. Klyuvitkin  N. V. Politova  A. N. Novigatsky  V. A. Silkin 《Oceanology》2016,56(6):819-836

The features of the vertical distribution of chlorophyll a, particulate organic carbon and its isotopic composition, total suspended particulate matter (SPM), and the structure of the phytoplankton community in the Middle and South Caspian Sea in May–June 2012 are discussed. The subsurface chlorophyll a maximum (SCM) was found everywhere at depths of ~20 to 40–60 m. The position of this layer is confined to the depth of the seasonal thermocline, which is determined by the development of a cold-water (dark) phytocenosis. The genesis of this layer was studied. The increase in chlorophyll a concentration in this layer is caused by an abundance of phytoplankton or an increased concentration of this phytopigments per algal cell. The highest values of the studied organic compounds and phytoplankton biomass are revealed as close to the seasonal thermocline extending from the southern periphery of the Derbent Depression to the Apsheron Sill, which is determined by the bottom topography. The presence of chlorophyll a at depths exceeding 300 m (up to ≥1 mg/m³) was revealed. This was supported by findings of individual algal cells containing chlorophyll a and even their accumulations in the deep water layer. The most probable mechanisms responsible for the presence of these cells at the deep water level are discussed in the paper. The vertical distribution of the values of the organic carbon isotopic composition is primarily controlled by the vertical structure of phytoplankton and chlorophyll a in the water column up to ~500 m and by biogeochemical processes at the redox barrier (~600 m layer). The relative stability of chlorophyll a and the stability of pheophytin a in anaerobic environments were verified. A significant amount of weakly transformed chlorophyll a was found close the sea bottom.  相似文献