共查询到20条相似文献，搜索用时 31 毫秒
1.
S. I. Pogosyan A. M. Durgaryan I. V. Konyukhov O. B. Chivkunova M. N. Merzlyak 《Oceanology》2009,49(6):866-871
A device for integrating cavity absorption measurements (ICAM) with an internal diameter of 80 mm suitable for field research
is described. The spectral features of the light absorption by some cyanobacteria, green algae, and diatoms in the integrating
sphere were studied and the dependences of the absorption on the cell concentration were determined in comparison with the
conventional measurements in a 1-cm cuvette. The sensitivity of the chlorophyll estimation with the ICAM reached 0.2–0.5 mg
m−3. The results of the ICAM application for the direct analysis of the natural phytoplankton and dissolved organic (“yellow“)
matter in the Black Sea and the Sea of Japan are described. 相似文献
2.
3.
Noboru Okami Motoaki Kishino Shigehiko Sugihara Noburu Takematsu Sanae Unoki 《Journal of Oceanography》1983,38(6):362-372
The spectral measurements of the attenuation coefficient of sea water and the absorption coefficient of suspended particles and of yellow substance were made with a spectrophotometer for the sea waters sampled in Tokyo Bay. These parameters can be used to compute the expected spectral irradiance reflectance. Some relationships between the optical properties of sea water and the concentration of dissolved organic carbon, the dry weight of suspended matter and chlorophyll-a concentration are presented. On the basis of these results, the possibility of modelling the relationship between optical and material properties is discussed. 相似文献
4.
The absorption coefficient of chromophoric dissolved organic matter (aCDOM) has been found to be correlated with fluorescence emission (excitation at 355 nm). In the coastal European Atlantic area and in the Western Mediterranean Sea (Gulf of Lions), a significant statistical dependence has been found between aCDOM and fluorescence with dissolved organic carbon (DOC) concentration. The relationship shows that, in the river plume areas (Rhine in the North Sea and Rhône in the Gulf of Lions), a consistent fraction of DOC (from 40% to 60% of the average of the DOC measured) is non-absorbing in visible light range, where the dissolved organic matter (DOM) is typically absorbent. In comparison, in the open sea, apparently not affected by the continental inputs, the entire DOC belongs to the chromophoric DOM whose specific absorption is lower (5 to 10 times) than that found in the river plume areas. 相似文献
5.
On the basis of the generalized data of multiannual observations (1985–1994), we analyze the seasonal variability of the vertical
and spatial distributions and composition (Csos, Nsos, Csos/cha, and C/N) of suspended organic substances (SOS) in the shelf zone and in the upper active layer of the abyssal part of the
Black Sea. The results of our analysis enable us to conclude that only a narrow coastal band of the shelf in the northwest
and west parts of the sea suffers to an extremely pronounced anthropogenic impact, which manifests itself in a significant
increase in the mass of suspended organic substances. The formation of new organic substances and, hence, the mass of suspended
organic substances in these regions attain the level of eutrophic waters in the late-spring and summer periods. In the open-sea
region, the anthropogenic impact is less pronounced and the spatial distribution of suspended organic substances is determined
by the general dynamics of waters and the intensity of phytoplankton production.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
6.
D. V. Alekseev V. A. Ivanov E. V. Ivancha V. V. Fomin L. V. Cherkesov 《Physical Oceanography》2007,17(1):1-16
The processes of roiling of the bottom sediments, diffusion transport of the suspension, and its repeated sedimentation on
the northwest shelf of the Black Sea caused by a moving cyclone are studied by using a numerical sigma-coordinate model. It
is supposed that bottom sediments are formed by particles of the same type. We determine the regions of the most intense rise
of the suspension, directions of its transport by the flows of water, and the vertical profiles of concentration of suspended
bottom sediments in different regions. In particular, it is shown that the distribution of suspended substances at a distance
of 1 m from the bottom reflects the location of the active and inactive centers of erosion.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 3–20, January–February, 2007. 相似文献
7.
Suhaimi Suratman Keith Weston Naomi Greenwood David B. Sivyer David J. Pearce Tim Jickells 《Estuarine, Coastal and Shelf Science》2010
The aim of this study was to investigate the cycling of dissolved inorganic and organic nutrients using moored instrumented buoys (SmartBuoys) during the spring bloom in the North Sea. The instrumentation on the buoys enabled high frequency measurements of water-column integrated irradiance and in situ chlorophyll to be made, and also preserved water sample collection which were used for dissolved inorganic and organic nutrient analyses. The SmartBuoys were located in the year-round well-mixed plume zone associated with the River Thames and in the summer stratified central North Sea. These site locations allowed comparison of nutrient concentrations and cycling, and spring bloom development at two contrasting sites. The spring bloom was expected to be initiated at both stations due to increasing insolation and decreasing suspended load leading to higher water-column integrated irradiance. Due to differences in suspended load between the sites, the spring bloom started ∼2 months earlier in the central North Sea. The spring bloom in the Thames plume also resulted in higher maximum phytoplankton biomass due to the higher pre-bloom nutrient concentrations associated with riverine input. The use of SmartBuoys is also shown to allow the cycling of dissolved organic nutrients to be examined over the critical, and often undersampled, spring bloom period. Dissolved Organic Nitrogen (DON) clearly increased during the spring bloom in the central North Sea compared to winter concentrations. DON also increased in the Thames plume although showing greater winter variability related to higher riverine and sedimentary dissolved organic matter input at this shallow (∼18 m) coastal site. DON increase during the spring bloom was therefore related to primary production at both sites probably due to active release by phytoplankton. At both stations DON decreased to pre-bloom concentrations as the bloom declined suggesting the released DON was bioavailable and removed due to heterotrophic uptake and production. The preserved nutrient samples from the central North Sea site were also suitable for Dissolved Organic Phosphorus (DOP) analysis due to their low suspended load with similar trends and cycling to DON, albeit at lower concentrations. This suggested similar processes controlling both DON and DOP. The variable timing of short term events such as the spring bloom makes sampling away from coastal regions difficult without the use of autonomous technology. This study demonstrates for the first time the applicability of using preserved samples from automated buoys for the measurement of dissolved organic nutrients. 相似文献
8.
《Journal of Sea Research》1999,41(1-2):35-53
Suspended matter samples filtered from surface waters and two depth profiles from the Flores Sea and Makasar Strait were investigated by electron probe X-ray microanalysis (EPXMA) and laser microprobe mass analysis (LAMMA). EPXMA yielded discrete morphological and chemical analysis of the major particle types of suspended matter. Cluster analysis revealed that thirteen main particle types described the composition of suspended matter of the Flores Sea and Makasar Strait. Silicates, aluminosilicates and Fe-oxyhydroxides were the predominant particle types. Suspended matter of the basins studied contained high levels of tin-bearing particles. On the basis of their composition, tin particles can be divided into three groups: (1) tin oxide/hydroxides (cassiterite, romarchite, hydroromarchite); (2) iron-oxyhydroxides with adsorbed tin; and (3) mixed oxidation state tin hydroxysulphates. Only ultra-fine cassiterite particles enter the seawater in suspended state. Dissolved tin species entering the sea have three alternatives: (1) to be scavenged by Fe-oxyhydroxides; (2) to precipitate as tin oxide/hydroxides (romarchite, hydroromarchite); (3) to precipitate as tin hydroxysulphates. The conclusion is that dissolved and suspended tin originate from local sources in the land frame of the basins as well as from remote sources in the Indonesian Archipelago. Four different sectors of the waters studied have suspended matter with different composition: (1) the Mahakam River–Delta zone; (2) the open Flores Sea; (3) the landlocked Saleh Bay; (4) the Makasar Strait proper. The depth distribution of suspended particle types is mainly influenced by: (1) the bottom nepheloid layer and calcite lysocline in the Flores Sea; (2) the high bioproduction in the surface water layer and the vertical distribution of organic matter in the Makasar Strait. 相似文献
9.
Preliminary study on the distribution of nutrients, organic matter, trace metals in sea surface microlayer in Xiamen Bay and Jiulong Estuary 总被引：1，自引：0，他引：1
-The enrichment of nutrients (NOa-, NOa-, PO43-), suspended particles, organic matter (POC, PON,DOC) , and trace metals (Cu, Ni, Cd) was determined in the sea surface microlayer of Xiamen Bay and Jiulong Estuary. The mean enrichment factors ([Xi]microlayer/[Xi ]15cm in depth) mostly ranged between 1 . 0 and 2. 0. The dissolved forms were the major forms of the components measured, the enrichment of dissolved organic matter and suspended particles could lead to the changes in the total amount and speciation of nutrients and trace metals. No correlation was observed between sample concentrations, speciation, enrichment factors and sample locations. However, some evidence shows that these parameters are correlated with sea state, indicating the complexity and dynamic nature of the sea surface microlayer. 相似文献
10.
We demonstrate the possibility of determination of the spectral characteristics of absorption and backward scattering of light
in the Black Sea according to the data of a SeaWiFS satellite device. We use specially selected data of observations obtained under favorable atmospheric conditions. It is shown
that the results of calculations performed by using different methods are almost identical and weakly depend on the model
parameters of the spectral course of the coefficients of absorption of light by yellow substance and its scattering by suspended
particles. 相似文献
11.
We present the data on the values of the coefficients of vertical attenuation and diffusive reflection of light in the Black
Sea in spring 1993 and 1995, compute the depths of one-percent quantum irradiation and the parameter Μ specifying the fraction
of attenuation of directed light as a result of scattering: Μ = σ/ɛ, and compare the characteristics of underwater irradiation
in the sea in different seasons for 1989–1995.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 44–48, May–June, 2005. 相似文献
12.
V. I. Man'kovsky 《Physical Oceanography》2001,11(3):299-304
On the basis of the data of optical investigations performed in the Black Sea, we develop a method for the evaluation of the
spectral values of underwater quantum irradiance within the band of photosynthetically active radiation according to the depth
of visibility of a Secchi disk and the intensity of illumination of the sea in luxes. The method is based on the use of the
correlations between the following optical parameters: of the vertical daylight attenuation factor α with the depth of visibility
of a Secchi disk and of the spectral values of α(λ) within the band of photosynthetically active radiation with α(λmin) for sea waters. This method is applicable in the winter-spring period when the seasonal thermocline is absent, the upper
layers of the sea are mixed, and the vertical distribution of α is uniform.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
13.
V. I. Man’kovsky 《Physical Oceanography》2012,21(5):305-319
We compute model spectra of the beam attenuation coefficient in surface waters of the Mediterranean Sea. These spectra are
used to determine the contribution of the components of seawater (suspended matter, yellow substance, pigments of phytoplankton,
and pure water) to the beam attenuation coefficient in different types of seawater. For the surface waters, we establish the
relationship between the light scattering coefficient and the attenuation coefficient at a wavelength of 547 nm and determine
the background (limiting minimum) value of the coefficient of absorption by the yellow substance in waters of the Mediterranean
Sea. It is compared with the values of the same parameter for some other basins (Black Sea, Lake Baikal, Baltic Sea, and oceanic
waters). 相似文献
14.
The distributional patterns of the dissolved forms of the major ions, biogenic elements, and trace elements were analyzed
in the mouth areas of small watersheds of the southern coast of the Kola Peninsula (the stream in the Por’ya Inlet, the Indera
River, and the Chavan’ga River). These results were compared to the data obtained under hydrochemical studies performed in
the river mouth areas of the White Sea basin. During the productive period, dissolved phosphates (20–46%) and dissolved silica
(3–22%) are removed from the continental runoff along the White Sea coast due to the biological assimilation of these elements.
The migrations of the major ions, as well as F, Rb, Cs, Sr, Mo, U, and Ni, may be described by the equation of the conservative
mixing of the riverine and seawater masses. The distribution of Ba is characterized by pronounced spatial variability and
is governed, apparently, by the sorption-desorption processes. An increase of the chloride concentration, which gradually
slows down at the marginal filter area, is observed together with the sharp decrease of the Fe, Al, Y, and rare earth elements
(La, Ce, Nd, and Dy), as well as for Ti and Zr. Presumably, this decrease is caused by the removal of these elements from
the solution by coagulation and flocculation as organic and organic-mineral colloids. The behavior of the dissolved Mn is
characterized by specific features in the river mouth areas of the White Sea, including the increase of its concentration
at the initial stages of the riverine-seawater mixing, which, in turn, is a result of its desorption from the terrigenous
suspended matter. This increase is followed by a nonlinear decrease, possibly, due to the flocculation of colloids. 相似文献
15.
16.
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
17.
南海北部生源要素的垂直输运和保存及其与东太平洋的对比研究 总被引：1，自引：0，他引：1
通过对南海北部夏、冬两个季节的生源要素垂直输运剖面和时间系列沉积物捕获器的测量资料进行综合研究表明:南海北部颗粒物质主要是由钙质生物壳、生物硅、海洋浮游生物的有机质以及岩源物质组成,颗粒物质通量在1 000 m处大约为90.0 mg/(m2·d);研究还表明颗粒有机碳在进入沉积物保存之前被大量溶解,南海北部来自底层顺坡搬运的有机碳远大于垂直沉降;与开阔大洋(东太平洋海域)的对比研究表明,边缘海对于季节的变化更加敏感,而东太平洋调查区位于热带赤道高生产力带,生物作用十分明显,其海洋生物呼吸和物质转移同样也较活跃. 相似文献
18.
《Journal of Sea Research》2002,47(3-4):303-315
Factors controlling the dynamics of suspended particulate matter (SPM), its influence on sea-leaving radiance and in-water optical properties, and the consequences of optical variation for phytoplankton growth, were studied at the ‘Processes of Vertical Exchange in Shelf Seas’ (PROVESS) project's southern North Sea site during April 1999. The optical properties of Netherlands coastal water were not unexpectedly found to be primarily determined by suspended sediment (Case 2) and were classified as Jerlov type 7 ‘relatively turbid coastal water’. During the study period, vertical mixing periodically resuspended optically active particles from the bed fluff layer throughout the water column and into the near-surface layer. These particles influenced sea surface radiance reflectance, and the red/green ratio of radiance reflectance, both of which can be observed by remote sensing. Linear relationships between sea surface radiance reflectance and SPM concentration were primarily determined by the inorganic fraction, as organic SPM varied little in concentration throughout the cruise period. The inorganic fraction was an important scatterer of light at all wavelengths, whereas the organic fraction displayed a greater tendency for light absorption at shorter wavelengths. Although the euphotic layer (depth of 1% surface irradiance) was only 8–10 m deep, vertical mixing ensured that phytoplankton throughout the water column (∼18 m) had access to PAR in excess of the estimated compensation illumination.Growth rates of microplankton (which includes pelagic microheterotrophs as well as phytoplankters) were calculated using an algorithm from the PROWQM model. These ranged from 0.1 to 0.3 d−1, and implied loss rates of 3–25% which were mostly attributed to mesozooplankton grazing. Estimated oxygen production, however, was in near equilibrium with oxygen demand observed in dark bottles, and implied a significant oxygen demand due to detrital respiration and nitrification. This was estimated as 3–6 mmol O2 m−3 d−1.In an order of magnitude timescale analysis, vertical mixing was found to be the single most important factor controlling the dynamics of SPM under mixed or stratified conditions. For a mixed water column microplankton aggregation and fluff layer resuspension also had the potential to redistribute material in the water column several times per day, whilst under stratified conditions horizontal exchange and inorganic particle sinking were more important. Resuspended material in a stratified water column remained below the pycnocline and had little impact on the near-surface layer optics. Other factors varied in importance with the level of stratification, which was recognised as a significant factor in determining the dynamics of SPM in this region of freshwater influence (ROFI). 相似文献
19.
Thomas R. Anderson Vladimir A. Ryabchenko Michael J.R. Fasham Victor A. Gorchakov 《Deep Sea Research Part I: Oceanographic Research Papers》2007,54(12):2082-2119
A three-dimensional hydrodynamic-ecosystem model was used to examine the factors determining the spatio-temporal distribution of denitrification in the Arabian Sea. The ecosystem model includes carbon and nitrogen as currencies, cycling of organic matter via detritus and dissolved organic matter, and both remineralization and denitrification as sinks for material exported below the euphotic zone. Model results captured the marked seasonality in plankton dynamics of the region, with characteristic blooms of chlorophyll in the coastal upwelling regions and central Arabian Sea during the southwest monsoon, and also in the northern Arabian Sea during the northeast monsoon as the mixed layer shoals. Predicted denitrification was 26.2 Tg N yr−1,the greatest seasonal contribution being during the northeast monsoon when primary production is co-located with the zone of anoxia. Detritus was the primary organic substrate consumed in denitrification (97%), with a small (3%) contribution by dissolved organic matter. Denitrification in the oxygen minimum zone was predicted to be fuelled almost entirely by organic matter supplied by particles sinking vertically from the euphotic zone above (0.73 mmol N m−2 d−1) rather than from lateral transport of organic matter from elsewhere in the Arabian Sea (less than 0.01 mmol N m−2 d−1). Analysis of the carbon budget in the zone of denitrification (north of 10°N and east of 55°E) indicates that the modelled vertical export flux of detritus, which is similar in magnitude to estimates from field data based on the 234Th method, is sufficient to account for measured bacterial production below the euphotic zone in the Arabian Sea. 相似文献
20.
The results of the analysis of samples of the Northern Dvina River’s suspended particulate matter obtained by the sedimentation
method from large water volumes in the periods of the spring high water and summer low water are presented. By the method
of sequential leaching using different reagents, four fractions have been separated: the F1 is the sorbed complex and carbonates,
the F2 is the amorphous hydroxides of Fe and Mn, the F3 is the form connected with the organic matter, and the F4 is the residual
or silicate-detrital (inert) form. The data have shown that all ten elements determined were grouped with respect to the ratio
of the distinguished forms: F4 is the predominant form for Al and Fe (73–88% of all the forms; however, the summer sample
contains only 38% of this form of iron, and F2 is the predominant form for this period with 46.6%). As to Mn, the F1, F2,
and F4 are nearly equally distributed in the spring high water samples, and only the F3 form is less important (5.4%). In
the summer sample, the manganese sorbed complex is predominant (53.5%); for Cu, Ni, Cr, and Co, the inert F4 form is predominant
(60–70%) in the sample of the spring suspended matter. The summer low water suspended matter has a lower F4 contribution (25–45%);
for Zn, Pb, and Cd, the equal distribution of the forms in the spring samples is typical, while the summer suspended matter
differs by the F2 form’s predominance (53–61% for Zn and Pb). The main conclusion from the acquired data is that the geochemical
mobility of all the studied elements, except for cadmium, in the summer low water suspended matter is higher than in the spring
suspended matter. The more intensive biogeochemical processes in August, the high level of organic matter, and the higher
contribution of phytoplankton lead to the intensification of the metals’ geochemical activity in the Northern Dvina suspended
matter in the end of the summer compared to the spring high water period when the physical processes are predominant over
the biogeochemical ones due to the high speeds of the freshened waters flow. 相似文献