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The quantitative distribution and grain-size composition of the suspended particulate matter (SPM) in the marginal filter
of the Severnaya Dvina River during the summer low-water periods of 2001–2005 were first analyzed in seawater on board of
the vessel immediately after its sampling (without preliminary treatment) using a Coulter counter. This analysis revealed
the main regularities in the transformation of the grain-size spectra at successive salinity steps of the marginal filter
as well as the boundaries between these steps based on the data obtained by direct complex studies of the SPM dispersion.
It is established that the water salinity is the main factor that controls the changes in the grain-size distribution and
the composition of the particulate matter in the marginal filter. The concentrations of the pelitic fraction and the salinity
demonstrate negative correlations between each other. It is shown that the areas characterized by the mass development of
phytoplankton are located along the outer boundary of the marginal filter (at the biological step), where the salinity amounts
to 23–24 psu. The content of the suspended forms of some chemical (lithogenic) elements and the Corg indicating the SPM’s genetic composition and their relations with the grain-size composition of the latter and the environments
are studied. 相似文献
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Novigatsky A. N. Lisitzin A. P. Shevchenko V. P. Klyuvitkin A. A. Kravchishina M. D. Politova N. V. 《Oceanology》2020,60(3):372-383
Oceanology - A new approach has been applied to studying marine sedimentation using dispersed sedimentary material in sediment traps compared to the surface layer of bottom sediments. Based on... 相似文献
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Oceanology - The article presents the results of studying the distribution and composition of dispersed sedimentary matter (suspended particulate matter, SPM) in the Barents Sea water column. The... 相似文献
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M. D. Kravchishina A. A. Klyuvitkin V. N. Lukashin N. V. Politova A. N. Novigatsky A. P. Lisitsyn 《Russian Meteorology and Hydrology》2018,43(10):697-705
The distribution of suspended particulate matter (SPM) and chlorophyll a in the Caspian Sea water column from April to November in 2008–2016 is analyzed. It is shown that the spatiotemporal variability of SPM concentration is defined by its sources, especially by the autochthonous (primary production) and allochthonous (particulate river runoff, aerosols) components. The effect of marginal filters of rivers on the volume of coming allochthonous SPM is considered. It is revealed that chlorophyll a is a reliable marker of the autochthonous component of SPM and biogenic sedimentation conditions. The stable vertical stratification defines the distribution of allochthonous and autochthonous SPM in the water column. Vertical profiles of these SPM components in the active layer (its thickness is usually up to ~60 m, more rarely to ~100 m) of the sea are similar in April and October-November and differ much in May-September. 相似文献
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The concentrations of suspended particulate matter (SPM) and particulate forms of the organic compounds (hydrocarbons, lipids, and chlorophyll a) were determined in the surface water layers of the Atlantic and Southern oceans during February to May of 2012 and 2014. It was found that the distribution of concentrations of the studied components is mainly affected by the location of frontal zones. When ice cover forms in the Southern Ocean, the changes in water temperature and phytoplankton development at the ice–water interface result in an increase of the concentrations of SPM, chlorophyll a, and, to a lesser extent, of lipids and hydrocarbons in the surface water layer. The occasional sharp increase of hydrocarbon concentrations caused by anthropogenic pollution was registered at local parts of water areas in the east of the Atlantic Ocean, as well as in the North and Baltic seas. 相似文献
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L. V. Ilyash L. S. Zhitina T. A. Belevich V. P. Shevchenko M. D. Kravchishina A. N. Pantyulin A. V. Tolstikov A. L. Chultsova 《Oceanology》2016,56(3):372-381
The species composition and biomass of phytoplankton, concentrations of chlorophyll a (Chl a) and nutrients, and accompanying hydrophysical conditions have been studied in the White Sea on July 6–11, 2009. The temperature of the surface water layer was lower than the multiyear average in July. Dinoflagellates dominated in the entire studied area; this was not the typical event for July. We suggest that domination of dinoflagellates was caused by low water temperature, when the nutrient regeneration rate was insufficient to support diatom growth. The abundance of microalgae and the structure of the phytoplankton community depended on the water structure. Variations in the phytoplankton community structure were caused not by substitution of specific species but rather by variability of the abundance of a single species, Heterocapsa triquetra. The highest phytoplankton biomass has been recorded in weakly stratified waters, where tidal mixing supplied the income of inorganic nutrients. The income of nutrients to the photic layer was limited in the stratified waters of Dvina Bay during the summer low-water period, so the phytoplankton abundance was low. We suggest that the lens of surface desalinated water presumably originated from the outlet of the Dvina River was registered in the central part of the White Sea. 相似文献
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A. P. Lisitzin A. A. Klyuvitkin V. I. Burenkov M. D. Kravchishina N. V. Politova A. N. Novigatsky V. P. Shevchenko T. S. Klyuvitkina 《Doklady Earth Sciences》2016,466(1):78-81
The main purpose of this work is to study the real distribution and spatial–temporal variations of suspended particulate matter and its main components in surface waters of the Atlantic Ocean on the basis of direct and satellite measurements for development of new and perfection of available algorithms for converting satellite data. The distribution fields of suspended particulate matter were calculated and plotted for the entire Atlantic Ocean. It is established that its distribution in the open ocean is subordinate to the latitudinal climatic zonality. The areas with maximum concentrations form latitudinal belts corresponding to high-productivity eutrophic and mesotrophic waters of the northern and southern temperate humid belts and with the equatorial humid zone. Phytoplankton, the productivity of which depends primarily on the climatic zonality, is the main producer of suspended particulate matter in the surface water layer. 相似文献
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Lithology and Mineral Resources - A model of the Ba geochemical cycle in the ocean is discussed based on a few own and published data. Barium ion reacts with the sulfate ion in various fluids (pore... 相似文献