259 resultados para Vladimir Mayakovsky


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Primary production in water column (P_p) varied from 107 to 312 mg C/m**2/day in Yenisey Bay: from 25 to 63 mg C/m**2/day in Obskaya Guba: and from 20 to 359 mg C/m**2/day in the open sea, that is: in the western Kara Sea and Ob-Yenisey shoals. The average concentration of chlorophyll a in the photosynthesis layer (C_ph) ranged from 0.2 to 1.8 mg/m**3 in these two regions, lower than in the estuaries of Ob (1.6-21.7 mg/m**3) and Yenisey (2.0-5.2 mg/m**3) Rivers. An inverse relation between surface salinity (S) and chlorophyll concentration (C_s) and chlorophyll concentration in the photosynthesis layer was found for all of the regions. The highest values of C_s and C_ph (0.8-22 mg/m**3) were measured at S<10 ppt, and the lowest values (0.2-0.8 mg/m**3) at S>22 ppt. A similar correlation of S with values of Pp occurred only in the Yenisey Bay and offshore regions. Obtained results agree well with the "outwelling" hypothesis. It states that large part of organic matter produced in estuaries is not used in estuarine trophic chains but is transported into adjacent sea areas and increases their productivity. Low values of Pp in the study regions may be attributed to such unfavorable factors as deficiency in nutrients, low temperature and turbidity, and lack of solar radiation.

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From July 4 to 18,1995 surface chlorophyll a concentrations (C_cs) and integral primary production (C_ps) were studied in the northeastern part of the Norwegian Sea (73°42'N; 13°16'E), over a test area where an accident of the nuclear submarine Komsomolets had taken place. It was found that during this interval C_cs decreased by factor of about 3.3 (from 0.78 to 0.24 mg/m**3); average chlorophyll concentration within the photo-synthetic layer (C_cl) decreased by factor of about 3.5 (from 0.97 to 0.28 mg/m**3). The value of C_ps in the water column varied slightly (from 445 to 539 mg C/m**2 per day), since decrease in C_cl was compensated both by 1.5-fold growth of the photosynthetic layer thickness (from 40 to 60 m) and by 2.1-fold increase in its average assimilation number (from 0.58 to 1.20 mg C/mg chl a per hour). Monthly averages of C_ps were obtained from published data on seasonal C_cs changes and on the level of incident solar irradiation. They were found to be less than 100 mg C/m**2 per day in March and October and 100-500 mg C/m**2 per day in April-June. Annual primary production calculated from above values was equal to 105 g C/m**2.

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Combined geodetic, geophysical and glaciological in situ measurements are interpreted regarding surface height changes over subglacial Lake Vostok and the local mass balance of the ice sheet at Vostok station. Repeated GPS observations spanning 5 years and long-term surface accumulation data show that the height of the lake surface has not changed over the observation period. The application of the mass conservation equation to purely observational data yields an ice mass balance for Vostok station close to equilibrium.

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This set provides 1779 CTD profiles of temperature and salinity measured with a russian "Zond-Bathometer" by the research vessels Yakov Gakkel and Vladimir Parshin, of the former Soviet Union, during 1987-1990. It is dedicated to the memory of Professor Ivan Ovchinnikov (1931-07-14 to 2000-06-10) who initiated the soviet program of research of the Mediterranean Sea and contributed significantly to the investigation of physical processes in the Mediterranean Sea.

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Results of comprehensive geological, geophysical and geochemical studies carried out in the Cape Verde Fracture Zone (Central Atlantic) during Cruise 9 of R/V ''Antares'' (1990-1991) are published in the book. Detailed characterization of various bedrock complexes (ultrabasites, gabbroids, dolerites, basalts, metamorphic rocks) is given. Geological conditions of newly found hydrothermal mineralization in the area are described. Problems of ore melts are under consideration. New data on hydrochemical anomalies and heat flow are given. The book contains original materials on sedimentary formations of the area.

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Mineralogy of suspended matter from surface and bottom waters has been studied at two sites in the Barents Sea. Along with terrigenous minerals, particulate matter samples contain authigenic mineral phases of iron and manganese oxyhydroxides. Mn-feroxyhite, Fe-vernadite, goethite, and proto-ferrihydrite have been identified in samples from the surface waters, whereas birnessite and non-ferruginous vernadite have been found in samples from the bottom waters. Formation of suspended manganese minerals in the bottom waters is explained by an additional Mn supply from underlying reduced sediments during their early diagenesis and oxygen depletion in the near-bottom nepheloid layer. Bacteria are supposed to take part in the authigenic mineral formation.