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1.
Data are presented on the content and composition of hydrocarbons (HC) (aliphatic, AHC and polyaromatic, PAH) in the filtered particulate matter and in the surface layer of the bottom sediments on the northern shelf of the Caspian Sea and related to the data on their content in the Volga River estuary. Because of the transformation and precipitation of anthropogenic and natural compounds, the HC composition in the particulate matter and bottom sediments undergoes transformations caused by the mixing of fresh and saline waters (in the bottom sediments, within the concentration ranges 70.4–4557.9 μ g/g for AHC and 3.8–4800 ng/g for PAH). It was found that the greatest concentrating of HC proceeds in the region of the avalanche sedimentation, and their content is independent of the grain-size type of the sediments. The anthropogenic HC (oil and pyrogenous) do not get over the marginal filter of the Volga River and do not pass to the open part of the sea. 相似文献
2.
I. A. Nemirovskaya 《Oceanology》2010,50(5):716-728
Data are presented on the content of aliphatic and polycyclic aromatic hydrocarbons (AHC and PAH, respectively) in the interstitial
waters and bottom sediments of the Kara Sea compared to the distribution of the particulate matter and organic carbon. It
was found that the AHC concentrations within the water mass (16 μg/l on average) are mainly formed by natural processes. The
AHC distribution represents the variability of the hydrological and sedimentation processes in different regions of the sea.
The widest ranges of the concentrations were registered in the Ob Bay-Kara Sea section: in the water (10–310 μg/l for the
AHC and 0.4–7.2 ng/l for the PAH) and in the surface layer of the bottom sediments (8–42 μg/l for the AHC and 9–94 ng/g for
the PAH). The differentiation of the hydrocarbons (HC) in the different media follows the marginal filter’s regularities;
therefore, no oil and pyrogenic compounds are supplied to the open parts of the sea. In the sediment mass, the HC content
is determined by the variations in the oxidative conditions in the sediment and its material’s composition. 相似文献
3.
Data on the contents and compositions of the hydrocarbons (HCs)—aliphatic (AHCs) and polycyclic aromatic (PAHs)—are provided
in comparison with the contents of the total organic carbon (Corg), the lipids in the particulates, and the Corg in bottom sediments. Particular attention has been paid to the distribution of the HCs in the water area of the Kravtsov
oil field. It has been established that the concentrations of AHCs in the water are governed by the content of particulates,
and the elevated AHC concentrations are confined to the coastal areas. In the water area of platform D-6, the sandy bottom
sediments were notable for the great variability of the HC concentrations, both laterally and from year to year. In the summer
of 2010, the content of AHCs averaged 40 μg/g (19% in the Corg), and that of PAHs, 23 ng/g. Natural seepage from the sediment mass is considered to be a source of HCs along with oil contamination. 相似文献
4.
In three sections in the Kara Sea, the contents of the dissolved and particulate organic carbon (the DOC and POC, respectively),
as well as of the organic carbon of the bottom sediments (Corg) were determined. The contents of varied from 6.3 to 2400 μg/l for the DOC and from 0.84 to 12.2 mg of C/l for the POC. The
average concentrations for all the samples tested amounted to 200 μg/l for the DOC (n = 78, σ = 368) and 2.7 mg/l for the POC (n = 92, σ = 2.7). The concentrations of Corg in the samples of the upper layer of the bottom sediments of the area treated
varied from 0.13 to 2.10% of the dry substance at an average value of 0.9% (n = 21, σ= 0.49%). It is shown that the distribution of the different forms of organic matter (OM) is an indicator of the supply
and spreading of the particulate matter in the Kara Sea and that the DOC and POC of the Kara Sea are formed under the impact
of the runoff of the Ob and Yenisei river waters. It is found that the distribution of the OM of the bottom sediments in the
surveyed area of the Kara Sea is closely related to their grain-size composition and to the structure of the currents in the
area studied. The variations in the Corg content in the bottom sediment cores from the zone of riverine and marine water mixing
represent the variability of the OM burial. 相似文献
5.
635 samples of suspended particulate matter (SPM), collected in the St. Lawrence river and estuary during periods of high and low river flow from a series of individual and anchor stations on a transect traversing the turbidity maximum zone, as well as two sediment box cores, were analyzed for Al, Si, Ca, Mg, Fe and Mn.An abrupt change in elemental composition occurs when traversing the front at the landward edge of the turbidity maximum. As the SPM concentration increases across the front from 20–200 mg l?1, the Ca/Al and Mg/Al ratios of the SPM increase and the Si/Al, Fe/Al and Mn/Al ratios decrease. The almost 50% decrease of the Mn/Al ratio is not related to changes in salinity. Within the turbidity maximum the tidal-averaged Si/Al, Ca/Al, Mg/Al and Fe/Al ratios of the SPM do not differ significantly from the landward to the seaward end of the turbidity zone, but on one tidal station the ratios of Si, Ca and Fe to Al are significantly lower at high river flow than at low flow. The Mn/Al ratio is insensitive to the extreme variations of either salinity (0.6–30‰) or SPM concentrations (10–480 mg l?1) within the turbidity zone. A tendency for higher Mn/Al ratios to be associated with near-bottom SPM, observed in the center of the turbidity zone during the low river flow period, is well developed in the lower reaches of the zone.Diagenetic mobilization within the rare fine-grained bottom sediments of the turbidity maximum is responsible for changes in Mn and Fe content of particulate matter, and early settling of coarse-grained components and size sorting within the zone are responsible for other compositional changes. Local sources, desorption and precipitation are apparently of secondary importance. The depletion of both Mn and Fe in the SPM and sediment of the upper estuary implies a net seaward escape of diagenetically mobilized metal. 相似文献
6.
Composition of the organic matter of the water,suspended matter,and bottom sediments in Nha Trang Bay in Vietnam in the South China Sea 总被引：1，自引：0，他引：1
V. I. Peresypkin A. V. Smurov N. A. Shulga E. S. Safonova T. G. Smurova Ch. V. Bang 《Oceanology》2011,51(6):959-968
Research has been conducted in Nha Trang Bay (Southern Vietnam, the South China Sea) at the section from the estuary of the
Cai River to the marine part of the bay, as well as in the area of coral reefs. The objects of the studies are the river and
sea waters, the suspended matter, and the bottom sediments. Data on the dissolved organic carbon and the total nitrogen in
the water are obtained. The organic carbon content is estimated in the suspended matter; the organic carbon and the molecular
and group composition of the n-alkanes are determined in the bottom sediments. The molecular and group composition of the n-alkanes in the bottom sediments of the landfill have made it possible to identify three types of organic matter (OM): marine,
mixed, and of mainly terrigenous origin. All the types of OM are closely related to the specificity of the sedimentation and
the hydrodynamics of the waters in this water area. 相似文献
7.
M. D. Kravchishina V. P. Shevchenko A. S. Filippov A. N. Novigatskii O. M. Dara T. N. Alekseeva V. A. Bobrov 《Oceanology》2010,50(3):365-385
The grain-size and mineral composition of the suspended particulate matter (SPM) of the Severnaya Dvina River mouth is studied,
as well as the content of several lithogenic elements in the SPM during the spring flood in May 2004. The data published on
the composition of the riverine SPM in the White Sea basin are very poor. The spring flood period when more than half of the
annual runoff is supplied from the river to the sea in a short time is understood more poorly. The report considers the comparison
results for the grain-size compositions of the SPM and the bottom sediments. The data of laser and hydraulic techniques of
the grain-size analysis are compared. The short-period variations of the SPM concentration and composition representing two
diurnal peaks of the tide level are studied. It is found that the SPM is mainly transferred during the spring flood as mineral
aggregates up to 40 μm diameter. The sandysilty fraction of the riverine SPM settles in the delta branches and channels, and
the bulk of the fine pelitic matter is supplied to the sea. The mineral and chemical composition of the Severnaya Dvina River
SPM is determined by the supply of substances from the drainage basin. This substance is subjected to intense mechanic separation
during the transfer to the sea. The key regularities of the formation of the mineral composition of the SPM during the flood
time are revealed. The effect of the grain-size composition of the SPM on the distribution of the minerals and elements studied
in the dynamic system of the river mouth are characterized. 相似文献
8.
Isotope parameters (δD, δ<Superscript>18</Superscript>O) and sources of freshwater input to Kara Sea
The isotope characteristics (δD, δ18О) of Kara Sea water were studied for quantitative estimation of freshwater runoff at stations located along transect from Yamal Peninsula to Blagopoluchiya Bay (Novaya Zemlya). Freshwater samples were studied for glaciers (Rose, Serp i Molot) and for Yenisei and Ob estuaries. As a whole, δD and δ18O are higher in glaciers than in river waters. isotope composition of estuarial water from Ob River is δD =–131.4 and δ18O =–17.6‰. Estuarial waters of Yenisei River are characterized by compositions close to those of Ob River (–134.4 and–17.7‰), as well as by isotopically “heavier” compositions (–120.7 and–15.8‰). Waters from studied section of Kara Sea can be product of mixing of freshwater (δD =–119.4, δ18O =–15.5) and seawater (S = 34.9, δD = +1.56, δ18O = +0.25) with a composition close to that of Barents Sea water. isotope parameters of water vary significantly with salinity in surface layer, and Kara Sea waters are desalinated along entire studied transect due to river runoff. concentration of freshwater is 5–10% in main part of water column, and <5% at a depth of >100 m. maximum contribution of freshwater (>65%) was recorded in surface layer of central part of sea. 相似文献
9.
A total of 150 samples were collected at a 10-days' anchor station in the Bornholm basin (55° 31.1′N, 15° 32.1′E) and analyzed for dissolved (< 0.4 μm) and particulate trace metals. For dissolved Mn, large gradients have been found in the vertical distribution with minimum concentrations (< 0.2 μgl?1) in the halocline zone and considerably higher values in the deep waters (up to 50 μgl?1). Ultrafiltration studies indicate that dissolved Mn is probably present as Mn2+ in the oxygenated bottom layer. The primary production process was not evident in the particulate Mn profile; the suspended particulate material (SPM), however, shows a considerable enrichment with depth, apparently due to Mn-oxide precipitation.The distribution of dissolved Fe was rather homogeneous, with average concentrations throughout the water column between 0.86 and 1.1 μgl?1, indicating that the oxidation of Fe2+ ions released from the sediments must already be complete in the very near oxidation boundary layer. Relatively high concentrations of particulate Fe were actually measured in the bottom layer, with the maximum mean of 11.2 μgl?1 at 72 m. Similarly to Mn, the profile of particulate Fe does not reflect the SPM curve of the eutrophic layer. On average, about 70% of the total Fe in surface waters was found to be particulate.The average concentrations of dissolved Zn, Cd and Cu were found to be rather homogeneous in the water column but showed a relatively high variability with time. A simplified model on trace-metal uptake by phytoplankton indicates no significant change in dissolved metal concentrations during the period of investigation. On average, only 1.7% Zn, 3.3% Cd and 9.8% Cu of the total metal concentrations were found in particulate form. SPM analyses showed significant correlations of Zn, Cd and Cu with Fe, indicating that particulate iron is an important carrier for particulate trace metals in Baltic waters. 相似文献
10.
Rare earth elements (REEs) of 91 fine-grained bottom sediment samples from five major rivers in Korea (the Han, Keum, and
Yeongsan) and China (the Changjiang and Huanghe) were studied to investigate their potential as source indicator for Yellow
Sea shelf sediments, this being the first synthetic report on REE trends for bottom sediments of these rivers. The results
show distinct differences in REE contents and their upper continental crust (UCC)-normalized patterns: compared to heavy rare
earth elements (HREEs), light rare earth elements (LREEs) are highly enriched in Korean river sediments, in contrast to Chinese
river sediments that have a characteristic positive Eu anomaly. This phenomenon is observed also in primary source rocks within
the river catchments. This suggests that source rock composition is the primary control on the REE signatures of these river
sediments, due largely to variations in the levels of chlorite and monazite, which are more abundant in Korean bottom river
sediments. Systematic variations in ΣLREE/ΣHREE ratios, and in (La/Yb)–(Gd/Yb)UCC but also (La/Lu)–(La/Y)UCC and (La/Y)–(Gd/Lu)UCC relations have the greatest discriminatory power. These findings are consistent with, but considerably expand on the limited
datasets available to date for suspended sediments. Evidently, the REE fingerprints of these river sediments can serve as
a useful diagnostic tool for tracing the provenance of sediments in the Yellow Sea, and for reconstructing their dispersal
patterns and the circulation system of the modern shelf, as well as the paleoenvironmental record of this and adjoining marginal
seas. 相似文献
11.
The thermohaline and hydrochemical characteristics of the Lena River’s estuarine zone were investigated in the Buor-Khaya
Bay and the southeastern Laptev Sea in September of 2005. A tongue of river water with high nutrient content and increased
turbidity was identified in the bay. It is shown that the two-layer structure in the bay is disturbed by warm freshwater lenses.
The strong vertical stratification in the shelf zone results in sharply contrasting characteristics of the surface and bottom
waters. It is established that the concentrations of biogenic elements regularly change depending on the thermohaline characteristics
of the waters and their stratification degree. Stagnant bottom waters with low dissolved oxygen contents and high concentrations
of phosphates, nitrates, and ammonium are recorded in the eastern part of the bay. The bottom waters have different hydrochemical
characteristics due to their different origin. 相似文献
12.
Methane in the water and bottom sediments of the mouth area of the Severnaya Dvina River (White Sea)
The mouth area of the Severnaya Dvina River is characterized by a high level of methane in the water (from 1.0 to 165.4 μl/l)
and in the bottom sediments (from 14 to 65000 μl/kg), being quite comparable to the productive mouth areas of the rivers in
the temperate zone. The maximum methane concentrations in the water and sediments were registered in the delta in the segments
of channels and branches with low rates of tidal and runoff currents to which domestic and industrial wastewaters are supplied.
In the riverine and marine water mixing zone with its upper boundary situated far into the delta and displaced depending on
the phase of the tidal cycle, a decrease of the methane amount with the salinity increase was observed. The prevailing role
in the formation of the methane content level in the water of the mouth area pertains to the bottom sediments, which is testified
to by the close correlation between the gas concentrations in these two media. The existence of periodicity in the variations
of the methane content level in the water of the river downstream caused by the tidal effects was found. 相似文献
13.
Spatiotemporal variability of the organic matter and the rates of its transformation in the Ob Inlet
The data on the qualitative and quantitative variability of the organic matter (OM) and its transformation rates in the waters of the Ob Inlet during different seasons are considered. The OM distribution was quite nonuniform over the entire Ob Inlet aquatic area: the concentrations of Corg varied from 2.8 to 14.1 mg/L and from 0.32 to 4.59 mg/L for the dissolved and particulate forms, respectively. The maximum concentrations of dissolved OM were registered in the main flow of the Ob River water supplied to the bay, whereas the minimum concentrations were characteristic for the near-bottom layers formed by the Kara Sea waters of high salinity in the northern part of the bay. Both in the summer and in the autumn, the fraction of particulate matter within the total OM reached its maximum values in the mixing zone of the Taz and Ob riverine waters, as well as in the mixing zone of the Ob River and Kara Sea waters. These boundary zones were characterized by the widest variability of the elemental (C: N: P) and biochemical (proteins and carbohydrates) composition of the OM, as well as of its transformation rates measured by the activities of the enzymes (alkaline phosphatase and the electron transport system). 相似文献
14.
黄河入海口壬基酚污染分布特征 总被引：2，自引：0，他引：2
黄河口表、底层水体和沉积物中壬基酚的浓度分布特征研究结果表明,表层水体中壬基酚浓度为15.7~148.6 ng/L,平均值为47.5 ng/L;底层水体中壬基酚浓度为15.8~52.7ng/L,平均值为31.0 ng/L;表层沉积物中壬基酚浓度为2.31~5.47 ng/g,平均浓度为3.87ng/g。黄河口水体中壬基酚浓度呈现由河道向出海口外逐渐降低的趋势;河道中表层沉积物壬基酚含量高于出海口外。黄河口水体中壬基酚浓度低于文献中报道的海河口水体中的浓度,表层沉积物中壬基酚含量低于珠江口文献报道值。水体中壬基酚浓度超过抑制藤壶附着浓度(10 ng/L),河道最上游的站点水体中的浓度超过影响太平洋牡蛎幼苗的发育并增加幼苗死亡率的浓度(100 ng/L)。 相似文献
15.
Kh. M. Saidova 《Oceanology》2009,49(4):499-504
Based upon the composition of the dominant species of benthic foraminifers in the bottom sediments sampled at 50 sampling
stations in the White Sea, their six assemblages (communities) were defined and mapped. The ranges of these communities depend
on the environmental factors determined by the bathymetric, latitudinal, and circum-continental sea zonalities, the sea currents,
the bottom upwellings, the continental runoff, the productivity of the waters, and the CaCO3 content in the near-bottom water layers and bottom sediments. 相似文献
16.
O. N. Zezina 《Oceanology》2008,48(6):832-836
Of particular interest in the vertical biological zoning of the continental slope in seas and oceans are the substantial differences in the composition, diversity, and abundance (biomass and production) of benthic faunal communities populating the upper and lower subzones of the bathyal zone. The upper bathyal subzone (down to depths of 1500 ± 500 m) resembles the neritic (shelf) one, while its lower subzone is characterized by both reduced diversity and biomass, being similar in its biological parameters to the near-slope abyssal zone (>3000 m). The study of the bottom contour currents and related sediments (contourites) made the geological prerequisites for such differences understandable. Based on a comparative analysis of the bionomical boundaries and core depths of the contour currents in the North Atlantic and Gulf of Alaska, a changing of trophic zones, as well as quantitative and production characteristics of benthic communities, are established. It is shown that the differences between the biological parameters of the upper and lower bathyal subzones (the benthic biomass, the feeding mode of invertebrates, the growth rate, and the maximal sizes of adult specimens) are related to geological agents such as roiling and redeposition of the sediments. 相似文献
17.
D. M. Polyakov 《Oceanology》2016,56(3):406-414
The REE contents (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) are determined by atomic emission spectroscopy in the subcolloidal fraction of bottom sediments in the Razdol’naya River–Amur Bay section. The mean contents of lanthanides in soils and river bottom sediments (before the mixing zone) are calculated. The increase in REE content and the fractioning in the series from light to middle and heavy REE in sediments of different estuary zones (river, water mixing, and marine), with the latter related to flocculation, sorption on iron and manganese hydroxides, clay minerals (hydromica, smectites), and lifetime accumulation of marine plankton, are dtermined. Via extraction of 0.5 N sodium hydroxide solution, the content of lanthanides associated with humic substances of subcolloidal fraction from the Amur Bay sediments are determined: 1.3 to 8.2% of La; 1.1 to 11% of Ce; and 0.3 to 1.5 of Gd. 相似文献
18.
I. A. Nemirovskaya 《Oceanology》2006,46(3):348-357
The data on the content and composition of lipids and aliphatic hydrocarbons (HC) in aerosols and surface waters obtained during the spring-summer periods of 2001 and 2003 along the vessel route from the North Sea to the Antarctic and backwards are presented. It was shown that the distribution of organic compounds is caused by the influence of the zonal supply of eolian matter from land, anthropogenic, and marine autochtonous sources. The concentrations of organic compounds in the aerosols varied from 0.22 to 13.04 ng/m3 for the lipids and from 0.04 to 7.03 ng/m3 for the aliphatic HC; in the surface waters, it from 9 to 84 and from 1 to 53 μg/l, respectively. There is a correlation between the fluxes of the lithogenic fraction of the aerosols, HC, and lipids. The growth of the aquatic area productivity increases the levels of the HC in the surface waters but to a lower degree than the HC supply with oil contamination. 相似文献
19.
20.
Ye. I. Polyakova Ye. A. Novichkova A. P. Lisitzin V. P. Shevchenko M. D. Kravchishina 《Oceanology》2016,56(2):289-300
Diatom algae, aquatic palynomorphs, and the grain-size of surface sediments from bays of the White Sea were investigated in a program dedicated to the study of marginal filters (MF) in the Severnaya Dvina, Onega, and Kem rivers. Three microalgal assemblages are established in surface sediments, which replace each other successively with distance from river mouths and are characterized by a gradual decrease in a share of freshwater species of diatoms and Chlorophyceae algae, significantly varying concentrations of marine diatoms and dinocysts due to changes in water salinity, grain-size composition of sediments, quantitative distribution of suspended particulate matter (SPM), and water productivity at different marginal filter stages. 相似文献