Pavel Tishchenko - Academia.edu (original) (raw)
Papers by Pavel Tishchenko
Journal of Chemical & Engineering Data, 2005
The solubility of carbon dioxide in aqueous HCl and NaHCO 3 solutions has been determined by the ... more The solubility of carbon dioxide in aqueous HCl and NaHCO 3 solutions has been determined by the coulometric technique at ambient pressure and at 278, 283, 287, and 298 K. The maximum molality of HCl and NaHCO 3 solutions was 1 and 0.5 mol‚kg-1 , respectively. The error in CO 2 solubility in HCl solutions estimated from parallel experiments was about 0.3%. For bicarbonate solutions, the overall error was larger because the solubility is the difference between the determined dissolved inorganic carbon and sodium bicarbonate molality. Under investigated conditions, errors in solubility data varied from (0.3% for dilute solutions to (1.3% for 0.5 m sodium bicarbonate. Obtained data were treated by the Pitzer method. Pitzer parameters λ CO2,NaHCO3 and λ CO2,HCl were derived as a function of temperature.
Science Bulletin
The goal of achieving carbon neutrality in the next 30-40 years is approaching worldwide consensu... more The goal of achieving carbon neutrality in the next 30-40 years is approaching worldwide consensus and requires coordinated efforts to combat the increasing threat of climate change. Two main sets of actions have been proposed to address this grand goal. One is to reduce anthropogenic CO 2 emissions to the atmosphere, and the other is to increase carbon sinks or negative emissions, i.e., removing CO 2 from the atmosphere. Here we advocate eco-engineering approaches for ocean negative carbon emission (ONCE), aiming to enhance carbon sinks in the marine environment. An international program is being established to promote coordinated efforts in developing ONCE-relevant strategies and methodologies, taking into consideration ecological/biogeochemical processes and mechanisms related to different forms of carbon (inorganic/organic, biotic/abiotic, particulate/dissolved) for sequestration. We focus on marine ecosystem-based approaches and pay special attention to mechanisms that require transformative research, including those elucidating interactions between the biological pump (BP), the microbial carbon pump (MCP), and microbially induced carbonate precipitation (MICP). Eutrophic estuaries, hypoxic and anoxic waters, coral reef ecosystems, as well as aquaculture areas are particularly considered in the context of efforts to increase their capacity as carbon sinks. ONCE approaches are thus expected to be beneficial for both carbon sequestration and alleviation of environmental stresses.
International Journal of Environmental Research and Public Health
The seasonal polycyclic aromatic hydrocarbon (PAH) variability was studied in the estuaries of th... more The seasonal polycyclic aromatic hydrocarbon (PAH) variability was studied in the estuaries of the Partizanskaya River and the Tumen River, the largest transboundary river of the Sea of Japan. The PAH levels were generally low over the year; however, the PAH concentrations increased according to one of two seasonal trends, which were either an increase in PAHs during the cold period, influenced by heating, or a PAH enrichment during the wet period due to higher run-off inputs. The major PAH source was the combustion of fossil fuels and biomass, but a minor input of petrogenic PAHs in some seasons was observed. Higher PAH concentrations were observed in fresh and brackish water compared to the saline waters in the Tumen River estuary, while the PAH concentrations in both types of water were similar in the Partizanskaya River estuary, suggesting different pathways of PAH input into the estuaries. The annual riverine PAH mass flux amounted to 0.028 t/year and 2.5 t/year for the Partiza...
Journal of Marine Science and Engineering, 2022
In this study, we investigated the carbonate system in sediments and water columns from five stat... more In this study, we investigated the carbonate system in sediments and water columns from five stations in the Sea of Japan (East Sea) (JES) during the R/V Hakuho Maru KH-10-2 research cruise in the summer of 2010. The total alkalinity (TA) and pH were measured. Adopting a saturation degree of 91% and 80% for the lysocline depth and calcite compensation depth (CCD), respectively, we found that those depths corresponded to 1360 and 1980 m. A comparison of the calcite saturation depths, lysocline depths, and CCD depths obtained for 1999 and 2010 suggests that acidification of the interior of the JES occurred. Sediment cores were retrieved using a multi-corer. In the sediment cores, a sharp decrease in the pH by 0.3–0.4 pH units was observed in the subsurface horizons (0–10 cm) compared with the pH of the seawater from the bottom horizons. The TA in the porewaters was significantly higher than that in the overlying seawater. The anaerobic degradation of organic matter is probably the mai...
Journal of Marine Science and Engineering
Hydrological conditions are an important factor for aquatic ecosystems. Their contribution to sti... more Hydrological conditions are an important factor for aquatic ecosystems. Their contribution to stimulating phytoplankton bloom in eutrophic estuaries is not quite clear. We present the results of an outbreak of a phytoplankton bloom event observed in the eutrophic Razdolnaya R. estuary in 2022 from January 22 to February 23, when the estuary was covered by ice. The bloom spreads over 21 km from the river mouth bar to upstream in the near-bottom layer below the halocline. The Chl-a concentration in the bloom area increased from 15 to 100 μg/L, and the dissolved oxygen concentration from 350 to 567 μmol/kg at a rate of 11 μmol/(kg day) over the study period, while the CO2 partial pressure was reduced to 108 µatm in the most oxygen-supersaturated waters. The Thalassiosira nordenskioeldii Cleve sea diatom was the dominant phytoplankton species in the bloom area. The opposite trend was observed near the boundary of the saline water wedge penetration over 29 km from the river mouth bar to ...
Estuarine, Coastal and Shelf Science, 2020
It has been established that the waters of the transboundary Razdolnaya (Suifen) and Tumannaya (T... more It has been established that the waters of the transboundary Razdolnaya (Suifen) and Tumannaya (Tumen) Rivers are highly polluted by nutrients. Loads of nutrients supplied by the Razdolnaya and Tumannaya Rivers cause eutrophication and induce seasonal hypoxia in areas off the river mouths in the Amursky Bay (northwestern part of Peter the Great bay (PGB)) and the Far Eastern Marine Biosphere Reserve (FEMBR) area (southwestern part of PGB). In both cases, hypoxia developed in the bottom waters in topographic depressions in the basins after the peak nutrient fluxes that occur in summer due to the monsoon climate. In 2013, anoxia occurred in the FEMBR area as a result of unusually heavy atmospheric precipitation at the end of July. The hypoxic areas expanded over approximately 60 km 2 and 17 km 2 in Amursky Bay and the FEMBR area, respectively. The hypoxia durations were approximately three months in 2011 in the semi-enclosed Amursky Bay and three weeks in 2014 in the more open FEMBR area. The observed hydrochemical anomalies (oxygen, phosphorus, silica, pH, DIC, ammonium) suggest that the main cause of hypoxia is degradation of "excess" diatoms on the water/sediment interface under dynamic water limitation. Mooring observations by a water quality monitoring station registered very high chlorophyll concentrations (approximately 50 mg/m 3) in the bottom waters of the FEMBR area. These high chlorophyll concentrations may be attributed to the topographic depression, which works as a sediment trap and accumulates organic matter. Sharply increasing of transparency of water column in the FEMBR area caused by replacement of coastal waters on the waters of open sea can to develop periphyton on seafloor. There is synchronization in deoxygenation of regional water basins (in our case it is the shelf and open part of the Sea of Japan) and global basins (oceans) which may be caused by variations in the chemical composition of atmosphere.
Journal of Marine Systems, 2021
Abstract The Japan/East Sea is well ventilated and is the most oxygen-rich region in the Pacific.... more Abstract The Japan/East Sea is well ventilated and is the most oxygen-rich region in the Pacific. However, quantitative estimates of the turbulent fluxes are missing due to a lack of observational data. To assess turbulent mixing, we employ data from the moored profiler Aqualog survey of April–October 2015 near the northwestern boundary of this region where the oxygen maximum is observed. The survey allowed observation of collocated depth profiles of conductivity, temperature, ocean current, and dissolved oxygen 8 times per day. The data were processed by using the Mixing (MX) Oceanographic Toolbox based on the fine-scale parameterization of turbulent dissipation. The dissipation rate, the eddy diffusivity and the diapycnal fluxes of heat, salt and oxygen are estimated in the depth range from 130 to 350 m throughout the profiler deployment period. The survey-averaged diffusivity increased with depth from 0.5 × 10−5 to 4.0 × 10−5 m2 s−1. The month-to-month variability in the mixing in the intermediate water is presented. Early in May 2015, a transition in mixing occurred from the winter regime with upward turbulent fluxes of both heat and salt to the summer regime with the downward mixing of heat. The turbulent mixing was elevated in June when large anticyclonic eddies passed the profiler mooring. The application of the eddy diffusivities to the profiler mooring oxygen data yields an average downward oxygen flux of roughly 8.6 mol m−2 month−1.
Journal of Chemical & Engineering Data, 2005
Geophysical Research Letters, 2003
Direct water mass renewal through convection deeper than 1000 m and the independent process of de... more Direct water mass renewal through convection deeper than 1000 m and the independent process of dense water production through brine rejection during sea ice formation occur at only a limited number of sites globally. Our late winter observations in 2000 and 2001 show that the Japan (East) Sea is a part of both exclusive groups. Japan Sea deep convection apparently occurs every winter, but massive renewal of bottom waters through brine rejection had not occurred for many decades prior to the extremely cold winter of 2001. The sites for both renewal mechanisms are south of Vladivostok, in the path of cold continental air outbreaks.
Bulletin of Environmental Contamination and Toxicology, 1992
Progress in Oceanography, 2004
Hydrographic properties from CTD and discrete bottle sample profiles covering the Japan (East) Se... more Hydrographic properties from CTD and discrete bottle sample profiles covering the Japan (East) Sea in summer, 1999, are presented in vertical sections, maps at standard depths, maps on isopycnal surfaces, and as property-property distributions. This data set covers most of the Sea with the exception of the western boundary region and northern Tatar Strait, and includes nutrients, pH, alkalinity, and chlorofluorocarbons, as well as the usual temperature, salinity, and oxygen observations.
Journal of Marine Science and Engineering
Seasonal hypoxia in the bottom waters of the Peter the Great Bay (PGB) of the Japan/East Sea (JES... more Seasonal hypoxia in the bottom waters of the Peter the Great Bay (PGB) of the Japan/East Sea (JES) occurs in summer. Using the empirical relationship between dissolved oxygen (DO) and pH obtained for hypoxic conditions and available historical DO data, acidification rates were estimated. Carefully sampled time-series observations from the northwestern part of the JES, carried out from 1999 to 2014 along the 132°20′ E and 134°00′ E longitudes, were chosen to determine the interannual variability of the sea’s hydrochemical parameters (DO, pH, and TA—the total alkalinity phosphates, nitrate, and silicates). To limit the effects of seasonal and spatial variability, only data obtained in the warm period were used. Additionally, all data from depths shallower than 500 m were discarded because they are affected by high natural variability, mostly due to strong mesoscale dynamic structures. Our results demonstrated that the pH and DO concentrations measured in the Upper Japan Sea Proper Wat...
Marine Biological Journal
Currently, the shallow basins with Zostera marina L. meadows are considered as absorbers of atmos... more Currently, the shallow basins with Zostera marina L. meadows are considered as absorbers of atmospheric carbon dioxide, capable of restraining an increase in its concentration. Due to its high primary productivity, eelgrass releases a large amount of oxygen into the environment. To establish the peculiarities of production activity in shallow-water basins, covered with Z. marina meadows, we conducted monitoring of hydrological and production indicators with different measurement intervals on the example of the Voevoda Bay (the Amur Bay, the Sea of Japan). Observations were carried out for eight and a half months (22.09.2012–07.06.2013). Measurements of temperature, salinity, chlorophyll fluorescence, and turbidity were carried out in Z. marina meadows at a depth of 4 m every three hours by a Water Quality Monitor hydrological station. Dissolved oxygen content was determined every hour by an optical oxygen sensor ARO-USB. Two types of oxygen concentration variability were established...
Polycyclic Aromatic Hydrocarbons
This chapter discusses the level of PAH pollution in the surface and deep waters of the northwest... more This chapter discusses the level of PAH pollution in the surface and deep waters of the northwestern part of the Japan Sea (NWJS). The investigated area included the river estuaries of the NWJS basin, the coastal regions, and the pelagic zone of the Japan Sea. As to spatial distributions, the concentration of 13 total PAHs ranged from 6.5 to 66.5 ng/L for river estuaries of South Primorye, and the concentration of 8 total PAHs was 31.2–105 ng/L for the Amur River Estuary. In the bays, the PAH content was 8–148.7 ng/L. The PAH pollution directly correlated with anthropogenic loads on surrounding territories. The open part of the Japan Sea demonstrates that the particulate PAH concentrations varied from 1.2 to 4.4 ng/L in 2009. There was an increasing trend for PAH content from the northeast of the Japan Sea to the southwest. Additionally, PAHs from coal and wood combustion predominated in surface waters of the north of the Japan Sea, while the main source of PAHs in the southwest of the Japan Sea was oil product combustion. In 2010 total PAH content ranged from 7.4 to 10.2 ng/L. The seasonal variation in the PAH concentrations was associated with emissions from the central and domestic heating systems. The results of the PAH distributions in the water column show that surface and intermediate waters (0–500 m) were more polluted than deep waters. Observed enhanced PAH levels on the depths from 30 to 500 m corresponded to biological pump activity.
Geochemistry International
Abstract —The diagenesis of organic matter (OM) is studied in bottom sediments taken in February,... more Abstract —The diagenesis of organic matter (OM) is studied in bottom sediments taken in February, 2018 from therapeutic mud deposits of the Uglovoi Bay and Voevoda and Ekspeditsiya bights (Peter the Great Bay, Sea of Japan). The carbonate system of bottom sediments and pore water were analyzed for the contents of nutrients, dissolved organic carbon, humic substance, and concentrations of sulfates and chlorides. The concentrations of organic carbon, chlorophyll-a, humic and fulvic acids, and mobile sulfide species are measured in a solid phase of sediment. Underwater photographing shows that sampling localities are covered by Zostera marina meadows in the Voevoda and Ekspeditsiya bights and by diatom mats in Uglovoi Bay. The proportions between dissolved inorganic carbon and alkalinity, as well as data on sulfate–chlorine ratios and mobile sulfide species indicate that the OM degradation in bottom sediments is mainly controlled by sulfate reduction. The Uglovoi Bay and Voevoda and Ekspeditsii bights are characterized by different values of bioturbation coefficients: 3.0, 107.6, and 14.5 cm 2 /day, respectively. The estimated fluxes of organic carbon from water into sediment and of dissolved inorganic carbon from sediment into water significantly differ. The disbalance between organic and inorganic carbons can be caused by the following reasons: (a) ignored CO 2 flux released by marine organisms from bottom sediments through their siphonal system; (b) partial OM consumption in food with its subsequent deposition in it.
Izvestiya TINRO
The Vostok Bay was surveyed on March 16–18, 2016 with measuring of water properties profiles by o... more The Vostok Bay was surveyed on March 16–18, 2016 with measuring of water properties profiles by oceanographic sondes Sea-Bird SBE-19plus V2 and Rinko Profiler ASTD-102 with sensors of pressure, temperature, conductivity, turbidity, chlorophyll fluorescence, dissolved oxygen, and photosynthetically active radiation (PAR) and collecting of water samples by SBE-32 carousel sampler with 10 liter bottles for further measuring of nutrients (P, Si and N in forms of nitrate and ammonium) and chlorophyll a concentration and phyto- and zooplankton abundance and species composition. Assimilation number (Pb ) of phytoplankton was determined using the optical sensor of dissolved oxygen mounted on logger Rinko AR01-USB and primary production was calculated from the measured values of Pb , Chl a and PAR. Values of primary production ranged from 200 to 2100 mgC/(m2.day). The highest phytoplankton growth was detected at the depth of 8–10 m in the northern Vostok Bay and 10–16 m in its southern part....
Doklady Earth Sciences
The hypoxia of the bottom waters in the Razdolnaya River estuary was observed for the first time ... more The hypoxia of the bottom waters in the Razdolnaya River estuary was observed for the first time in September 2014 during the survey. It is formed as in the seaward part: oxygen is absorbed as a result of destruction of excessive phytoplankton biomass that settles to the bottom and is synthesized on the upper horizon. The high value of primary production in the riverine part of the estuary was caused by the pycnocline formed. Thus, phytoplankton "blooms" above and undergoes destruction beneath the pycnocline. Oxygen is distributed symmetrically in both parts of the estuary with respect to a bar: similar oxygen concentrations, which are maximum on the surface and minimum at the bottom, 300 and <60 μm/L, respectively, are recorded. The anomalies of hydrochemical parameters that have been formed during this process are sharply different in the two parts of the estuary, which most vividly manifests itself in the N/P value and the partial pressure of carbon dioxide pCO 2. The causes of this unique situation are discussed.
Izvestiya TINRO
Chemical water parameters in the Partizanskaya River estuary were measured on July 18–19, 2012 in... more Chemical water parameters in the Partizanskaya River estuary were measured on July 18–19, 2012 in conditions of low water discharge (20.1 m3 /s). In these conditions, the cline of salt water at the bottom penetrated up to 11 km upstream from the river mouth and the fresh river water passed the estuarine zone of mixing in approximately 2 days. Salt composition of the mixed water in the estuary had conservative dependence on salinity. By dynamical signs, the estuary could be divided into two zones: i) zone of active exchange between the surface freshwater layer and the bottom salted layer on the distance 5.5 km from the river mouth to the first sandy riverbank that the fresh river water passed in 12 hours, and ii) the upper part of the estuary with limited water exchange. The complex of water environments in the estuary, as good water transparency, strong stratification, and high concentrations of terrestrial nutrients, was favorable for phytoplankton blooming, so the chlorophyll conc...
Izvestiya TINRO
Environmental conditions in the Razdolnaya/Suifen Estuary and adjacent marine area were monitored... more Environmental conditions in the Razdolnaya/Suifen Estuary and adjacent marine area were monitored from 2008 to 2018, by seasons, including winter observations in January 2014 and January 2018. The river discharge in winter was low: 6 m3 /s (mean annual discharge is 73 m3 /s). The estuary was covered by ice. The cline of salt water at the bottom was traced upstream up to 28 km from the river mouth. The currents in the estuary changed in tidal cycle. Increasing of salinity and temperature (> 2о ) at the bottom was observed in the distance 20–24 km from the river bar (this area was distinguished by relatively thin ice, 20 cm, against 40–70 cm in the rest of estuary). Modeling of the water balance in the estuary showed an additional source of salt water in the internal estuary, beyond the direct exchange with the sea over the river bar, that was presumably the water flow through the aquifer. This groundwater discharge was responsible for supporting of the salted bottom layer and for ...
Journal of Chemical & Engineering Data, 2005
The solubility of carbon dioxide in aqueous HCl and NaHCO 3 solutions has been determined by the ... more The solubility of carbon dioxide in aqueous HCl and NaHCO 3 solutions has been determined by the coulometric technique at ambient pressure and at 278, 283, 287, and 298 K. The maximum molality of HCl and NaHCO 3 solutions was 1 and 0.5 mol‚kg-1 , respectively. The error in CO 2 solubility in HCl solutions estimated from parallel experiments was about 0.3%. For bicarbonate solutions, the overall error was larger because the solubility is the difference between the determined dissolved inorganic carbon and sodium bicarbonate molality. Under investigated conditions, errors in solubility data varied from (0.3% for dilute solutions to (1.3% for 0.5 m sodium bicarbonate. Obtained data were treated by the Pitzer method. Pitzer parameters λ CO2,NaHCO3 and λ CO2,HCl were derived as a function of temperature.
Science Bulletin
The goal of achieving carbon neutrality in the next 30-40 years is approaching worldwide consensu... more The goal of achieving carbon neutrality in the next 30-40 years is approaching worldwide consensus and requires coordinated efforts to combat the increasing threat of climate change. Two main sets of actions have been proposed to address this grand goal. One is to reduce anthropogenic CO 2 emissions to the atmosphere, and the other is to increase carbon sinks or negative emissions, i.e., removing CO 2 from the atmosphere. Here we advocate eco-engineering approaches for ocean negative carbon emission (ONCE), aiming to enhance carbon sinks in the marine environment. An international program is being established to promote coordinated efforts in developing ONCE-relevant strategies and methodologies, taking into consideration ecological/biogeochemical processes and mechanisms related to different forms of carbon (inorganic/organic, biotic/abiotic, particulate/dissolved) for sequestration. We focus on marine ecosystem-based approaches and pay special attention to mechanisms that require transformative research, including those elucidating interactions between the biological pump (BP), the microbial carbon pump (MCP), and microbially induced carbonate precipitation (MICP). Eutrophic estuaries, hypoxic and anoxic waters, coral reef ecosystems, as well as aquaculture areas are particularly considered in the context of efforts to increase their capacity as carbon sinks. ONCE approaches are thus expected to be beneficial for both carbon sequestration and alleviation of environmental stresses.
International Journal of Environmental Research and Public Health
The seasonal polycyclic aromatic hydrocarbon (PAH) variability was studied in the estuaries of th... more The seasonal polycyclic aromatic hydrocarbon (PAH) variability was studied in the estuaries of the Partizanskaya River and the Tumen River, the largest transboundary river of the Sea of Japan. The PAH levels were generally low over the year; however, the PAH concentrations increased according to one of two seasonal trends, which were either an increase in PAHs during the cold period, influenced by heating, or a PAH enrichment during the wet period due to higher run-off inputs. The major PAH source was the combustion of fossil fuels and biomass, but a minor input of petrogenic PAHs in some seasons was observed. Higher PAH concentrations were observed in fresh and brackish water compared to the saline waters in the Tumen River estuary, while the PAH concentrations in both types of water were similar in the Partizanskaya River estuary, suggesting different pathways of PAH input into the estuaries. The annual riverine PAH mass flux amounted to 0.028 t/year and 2.5 t/year for the Partiza...
Journal of Marine Science and Engineering, 2022
In this study, we investigated the carbonate system in sediments and water columns from five stat... more In this study, we investigated the carbonate system in sediments and water columns from five stations in the Sea of Japan (East Sea) (JES) during the R/V Hakuho Maru KH-10-2 research cruise in the summer of 2010. The total alkalinity (TA) and pH were measured. Adopting a saturation degree of 91% and 80% for the lysocline depth and calcite compensation depth (CCD), respectively, we found that those depths corresponded to 1360 and 1980 m. A comparison of the calcite saturation depths, lysocline depths, and CCD depths obtained for 1999 and 2010 suggests that acidification of the interior of the JES occurred. Sediment cores were retrieved using a multi-corer. In the sediment cores, a sharp decrease in the pH by 0.3–0.4 pH units was observed in the subsurface horizons (0–10 cm) compared with the pH of the seawater from the bottom horizons. The TA in the porewaters was significantly higher than that in the overlying seawater. The anaerobic degradation of organic matter is probably the mai...
Journal of Marine Science and Engineering
Hydrological conditions are an important factor for aquatic ecosystems. Their contribution to sti... more Hydrological conditions are an important factor for aquatic ecosystems. Their contribution to stimulating phytoplankton bloom in eutrophic estuaries is not quite clear. We present the results of an outbreak of a phytoplankton bloom event observed in the eutrophic Razdolnaya R. estuary in 2022 from January 22 to February 23, when the estuary was covered by ice. The bloom spreads over 21 km from the river mouth bar to upstream in the near-bottom layer below the halocline. The Chl-a concentration in the bloom area increased from 15 to 100 μg/L, and the dissolved oxygen concentration from 350 to 567 μmol/kg at a rate of 11 μmol/(kg day) over the study period, while the CO2 partial pressure was reduced to 108 µatm in the most oxygen-supersaturated waters. The Thalassiosira nordenskioeldii Cleve sea diatom was the dominant phytoplankton species in the bloom area. The opposite trend was observed near the boundary of the saline water wedge penetration over 29 km from the river mouth bar to ...
Estuarine, Coastal and Shelf Science, 2020
It has been established that the waters of the transboundary Razdolnaya (Suifen) and Tumannaya (T... more It has been established that the waters of the transboundary Razdolnaya (Suifen) and Tumannaya (Tumen) Rivers are highly polluted by nutrients. Loads of nutrients supplied by the Razdolnaya and Tumannaya Rivers cause eutrophication and induce seasonal hypoxia in areas off the river mouths in the Amursky Bay (northwestern part of Peter the Great bay (PGB)) and the Far Eastern Marine Biosphere Reserve (FEMBR) area (southwestern part of PGB). In both cases, hypoxia developed in the bottom waters in topographic depressions in the basins after the peak nutrient fluxes that occur in summer due to the monsoon climate. In 2013, anoxia occurred in the FEMBR area as a result of unusually heavy atmospheric precipitation at the end of July. The hypoxic areas expanded over approximately 60 km 2 and 17 km 2 in Amursky Bay and the FEMBR area, respectively. The hypoxia durations were approximately three months in 2011 in the semi-enclosed Amursky Bay and three weeks in 2014 in the more open FEMBR area. The observed hydrochemical anomalies (oxygen, phosphorus, silica, pH, DIC, ammonium) suggest that the main cause of hypoxia is degradation of "excess" diatoms on the water/sediment interface under dynamic water limitation. Mooring observations by a water quality monitoring station registered very high chlorophyll concentrations (approximately 50 mg/m 3) in the bottom waters of the FEMBR area. These high chlorophyll concentrations may be attributed to the topographic depression, which works as a sediment trap and accumulates organic matter. Sharply increasing of transparency of water column in the FEMBR area caused by replacement of coastal waters on the waters of open sea can to develop periphyton on seafloor. There is synchronization in deoxygenation of regional water basins (in our case it is the shelf and open part of the Sea of Japan) and global basins (oceans) which may be caused by variations in the chemical composition of atmosphere.
Journal of Marine Systems, 2021
Abstract The Japan/East Sea is well ventilated and is the most oxygen-rich region in the Pacific.... more Abstract The Japan/East Sea is well ventilated and is the most oxygen-rich region in the Pacific. However, quantitative estimates of the turbulent fluxes are missing due to a lack of observational data. To assess turbulent mixing, we employ data from the moored profiler Aqualog survey of April–October 2015 near the northwestern boundary of this region where the oxygen maximum is observed. The survey allowed observation of collocated depth profiles of conductivity, temperature, ocean current, and dissolved oxygen 8 times per day. The data were processed by using the Mixing (MX) Oceanographic Toolbox based on the fine-scale parameterization of turbulent dissipation. The dissipation rate, the eddy diffusivity and the diapycnal fluxes of heat, salt and oxygen are estimated in the depth range from 130 to 350 m throughout the profiler deployment period. The survey-averaged diffusivity increased with depth from 0.5 × 10−5 to 4.0 × 10−5 m2 s−1. The month-to-month variability in the mixing in the intermediate water is presented. Early in May 2015, a transition in mixing occurred from the winter regime with upward turbulent fluxes of both heat and salt to the summer regime with the downward mixing of heat. The turbulent mixing was elevated in June when large anticyclonic eddies passed the profiler mooring. The application of the eddy diffusivities to the profiler mooring oxygen data yields an average downward oxygen flux of roughly 8.6 mol m−2 month−1.
Journal of Chemical & Engineering Data, 2005
Geophysical Research Letters, 2003
Direct water mass renewal through convection deeper than 1000 m and the independent process of de... more Direct water mass renewal through convection deeper than 1000 m and the independent process of dense water production through brine rejection during sea ice formation occur at only a limited number of sites globally. Our late winter observations in 2000 and 2001 show that the Japan (East) Sea is a part of both exclusive groups. Japan Sea deep convection apparently occurs every winter, but massive renewal of bottom waters through brine rejection had not occurred for many decades prior to the extremely cold winter of 2001. The sites for both renewal mechanisms are south of Vladivostok, in the path of cold continental air outbreaks.
Bulletin of Environmental Contamination and Toxicology, 1992
Progress in Oceanography, 2004
Hydrographic properties from CTD and discrete bottle sample profiles covering the Japan (East) Se... more Hydrographic properties from CTD and discrete bottle sample profiles covering the Japan (East) Sea in summer, 1999, are presented in vertical sections, maps at standard depths, maps on isopycnal surfaces, and as property-property distributions. This data set covers most of the Sea with the exception of the western boundary region and northern Tatar Strait, and includes nutrients, pH, alkalinity, and chlorofluorocarbons, as well as the usual temperature, salinity, and oxygen observations.
Journal of Marine Science and Engineering
Seasonal hypoxia in the bottom waters of the Peter the Great Bay (PGB) of the Japan/East Sea (JES... more Seasonal hypoxia in the bottom waters of the Peter the Great Bay (PGB) of the Japan/East Sea (JES) occurs in summer. Using the empirical relationship between dissolved oxygen (DO) and pH obtained for hypoxic conditions and available historical DO data, acidification rates were estimated. Carefully sampled time-series observations from the northwestern part of the JES, carried out from 1999 to 2014 along the 132°20′ E and 134°00′ E longitudes, were chosen to determine the interannual variability of the sea’s hydrochemical parameters (DO, pH, and TA—the total alkalinity phosphates, nitrate, and silicates). To limit the effects of seasonal and spatial variability, only data obtained in the warm period were used. Additionally, all data from depths shallower than 500 m were discarded because they are affected by high natural variability, mostly due to strong mesoscale dynamic structures. Our results demonstrated that the pH and DO concentrations measured in the Upper Japan Sea Proper Wat...
Marine Biological Journal
Currently, the shallow basins with Zostera marina L. meadows are considered as absorbers of atmos... more Currently, the shallow basins with Zostera marina L. meadows are considered as absorbers of atmospheric carbon dioxide, capable of restraining an increase in its concentration. Due to its high primary productivity, eelgrass releases a large amount of oxygen into the environment. To establish the peculiarities of production activity in shallow-water basins, covered with Z. marina meadows, we conducted monitoring of hydrological and production indicators with different measurement intervals on the example of the Voevoda Bay (the Amur Bay, the Sea of Japan). Observations were carried out for eight and a half months (22.09.2012–07.06.2013). Measurements of temperature, salinity, chlorophyll fluorescence, and turbidity were carried out in Z. marina meadows at a depth of 4 m every three hours by a Water Quality Monitor hydrological station. Dissolved oxygen content was determined every hour by an optical oxygen sensor ARO-USB. Two types of oxygen concentration variability were established...
Polycyclic Aromatic Hydrocarbons
This chapter discusses the level of PAH pollution in the surface and deep waters of the northwest... more This chapter discusses the level of PAH pollution in the surface and deep waters of the northwestern part of the Japan Sea (NWJS). The investigated area included the river estuaries of the NWJS basin, the coastal regions, and the pelagic zone of the Japan Sea. As to spatial distributions, the concentration of 13 total PAHs ranged from 6.5 to 66.5 ng/L for river estuaries of South Primorye, and the concentration of 8 total PAHs was 31.2–105 ng/L for the Amur River Estuary. In the bays, the PAH content was 8–148.7 ng/L. The PAH pollution directly correlated with anthropogenic loads on surrounding territories. The open part of the Japan Sea demonstrates that the particulate PAH concentrations varied from 1.2 to 4.4 ng/L in 2009. There was an increasing trend for PAH content from the northeast of the Japan Sea to the southwest. Additionally, PAHs from coal and wood combustion predominated in surface waters of the north of the Japan Sea, while the main source of PAHs in the southwest of the Japan Sea was oil product combustion. In 2010 total PAH content ranged from 7.4 to 10.2 ng/L. The seasonal variation in the PAH concentrations was associated with emissions from the central and domestic heating systems. The results of the PAH distributions in the water column show that surface and intermediate waters (0–500 m) were more polluted than deep waters. Observed enhanced PAH levels on the depths from 30 to 500 m corresponded to biological pump activity.
Geochemistry International
Abstract —The diagenesis of organic matter (OM) is studied in bottom sediments taken in February,... more Abstract —The diagenesis of organic matter (OM) is studied in bottom sediments taken in February, 2018 from therapeutic mud deposits of the Uglovoi Bay and Voevoda and Ekspeditsiya bights (Peter the Great Bay, Sea of Japan). The carbonate system of bottom sediments and pore water were analyzed for the contents of nutrients, dissolved organic carbon, humic substance, and concentrations of sulfates and chlorides. The concentrations of organic carbon, chlorophyll-a, humic and fulvic acids, and mobile sulfide species are measured in a solid phase of sediment. Underwater photographing shows that sampling localities are covered by Zostera marina meadows in the Voevoda and Ekspeditsiya bights and by diatom mats in Uglovoi Bay. The proportions between dissolved inorganic carbon and alkalinity, as well as data on sulfate–chlorine ratios and mobile sulfide species indicate that the OM degradation in bottom sediments is mainly controlled by sulfate reduction. The Uglovoi Bay and Voevoda and Ekspeditsii bights are characterized by different values of bioturbation coefficients: 3.0, 107.6, and 14.5 cm 2 /day, respectively. The estimated fluxes of organic carbon from water into sediment and of dissolved inorganic carbon from sediment into water significantly differ. The disbalance between organic and inorganic carbons can be caused by the following reasons: (a) ignored CO 2 flux released by marine organisms from bottom sediments through their siphonal system; (b) partial OM consumption in food with its subsequent deposition in it.
Izvestiya TINRO
The Vostok Bay was surveyed on March 16–18, 2016 with measuring of water properties profiles by o... more The Vostok Bay was surveyed on March 16–18, 2016 with measuring of water properties profiles by oceanographic sondes Sea-Bird SBE-19plus V2 and Rinko Profiler ASTD-102 with sensors of pressure, temperature, conductivity, turbidity, chlorophyll fluorescence, dissolved oxygen, and photosynthetically active radiation (PAR) and collecting of water samples by SBE-32 carousel sampler with 10 liter bottles for further measuring of nutrients (P, Si and N in forms of nitrate and ammonium) and chlorophyll a concentration and phyto- and zooplankton abundance and species composition. Assimilation number (Pb ) of phytoplankton was determined using the optical sensor of dissolved oxygen mounted on logger Rinko AR01-USB and primary production was calculated from the measured values of Pb , Chl a and PAR. Values of primary production ranged from 200 to 2100 mgC/(m2.day). The highest phytoplankton growth was detected at the depth of 8–10 m in the northern Vostok Bay and 10–16 m in its southern part....
Doklady Earth Sciences
The hypoxia of the bottom waters in the Razdolnaya River estuary was observed for the first time ... more The hypoxia of the bottom waters in the Razdolnaya River estuary was observed for the first time in September 2014 during the survey. It is formed as in the seaward part: oxygen is absorbed as a result of destruction of excessive phytoplankton biomass that settles to the bottom and is synthesized on the upper horizon. The high value of primary production in the riverine part of the estuary was caused by the pycnocline formed. Thus, phytoplankton "blooms" above and undergoes destruction beneath the pycnocline. Oxygen is distributed symmetrically in both parts of the estuary with respect to a bar: similar oxygen concentrations, which are maximum on the surface and minimum at the bottom, 300 and <60 μm/L, respectively, are recorded. The anomalies of hydrochemical parameters that have been formed during this process are sharply different in the two parts of the estuary, which most vividly manifests itself in the N/P value and the partial pressure of carbon dioxide pCO 2. The causes of this unique situation are discussed.
Izvestiya TINRO
Chemical water parameters in the Partizanskaya River estuary were measured on July 18–19, 2012 in... more Chemical water parameters in the Partizanskaya River estuary were measured on July 18–19, 2012 in conditions of low water discharge (20.1 m3 /s). In these conditions, the cline of salt water at the bottom penetrated up to 11 km upstream from the river mouth and the fresh river water passed the estuarine zone of mixing in approximately 2 days. Salt composition of the mixed water in the estuary had conservative dependence on salinity. By dynamical signs, the estuary could be divided into two zones: i) zone of active exchange between the surface freshwater layer and the bottom salted layer on the distance 5.5 km from the river mouth to the first sandy riverbank that the fresh river water passed in 12 hours, and ii) the upper part of the estuary with limited water exchange. The complex of water environments in the estuary, as good water transparency, strong stratification, and high concentrations of terrestrial nutrients, was favorable for phytoplankton blooming, so the chlorophyll conc...
Izvestiya TINRO
Environmental conditions in the Razdolnaya/Suifen Estuary and adjacent marine area were monitored... more Environmental conditions in the Razdolnaya/Suifen Estuary and adjacent marine area were monitored from 2008 to 2018, by seasons, including winter observations in January 2014 and January 2018. The river discharge in winter was low: 6 m3 /s (mean annual discharge is 73 m3 /s). The estuary was covered by ice. The cline of salt water at the bottom was traced upstream up to 28 km from the river mouth. The currents in the estuary changed in tidal cycle. Increasing of salinity and temperature (> 2о ) at the bottom was observed in the distance 20–24 km from the river bar (this area was distinguished by relatively thin ice, 20 cm, against 40–70 cm in the rest of estuary). Modeling of the water balance in the estuary showed an additional source of salt water in the internal estuary, beyond the direct exchange with the sea over the river bar, that was presumably the water flow through the aquifer. This groundwater discharge was responsible for supporting of the salted bottom layer and for ...