We provide an expert quality assessment of the data for 1932 1993 and used these data to perform the numerical analysis of the carbonate system of the aerobic zone in the Black Sea. The intraannual and long-term variations of the carbonate system are studied in the abyssal part of the sea for 1960-1993. We propose explanations of the intraannual variations of the analyzed system for various layers of the aerobic zone and reveal long-term variations of the pH values, total alkalinity, and the ratios of the components of the carbonate system. We discover and explain the observed increase in the concentrations of 2 and 2 and the partial pressure of carbon dioxide 2 , as well as a decrease in values and the concentration of 3 2-in waters of the aerobic zone of the Black Sea.The carbonate system is the sum of all inorganic forms of carbon and represents the most important component of the total budget and turnover of carbon in marine media, i.e., of one of the main cycles of the turnover of substances in nature. In seawater, the inorganic carbon has three different forms, namely, carbon dioxide CO 2 (aq) dissolved in seawater, bicarbonate HCO 3 , and carbonate-ions CO 3 2 .The carbonate system is probably the most complicated biogeochemical system of the sea. It is described by the following equations of chemical equilibrium [1, 2]: CO 2 (g) + nH 2 O CO 2 nH 2 O(H 2 CO 3 , CO 2 (aq))where the concentration of CO 2 is determined according to the Henry law [CO 2 ] = K 0 (T , S)pCO 2 (2) and K 0 is the coefficient of solubility of CO 2 in seawater, CO 2 (aq)
Assessment of state and quality of the sea and ocean surface layer waters resulted from binding the data from satellite images and the results of the simultaneously done in situ measurements is the actual direction of modern complex oceanological studies. Further development of this direction the immediate task of which consists in defining hydrochemical composition of water based on satellite data requires selecting the regions in the Black Sea where in situ measurements of water hydrochemical characteristics can be carried out simultaneously with satellite monitoring of the surface water state. The results of analysis of the hydrochemical characteristics' (main elements of nutrient and carbon cycles) spatial distribution in the Blue Bay waters based on the data of the expeditionary research carried out by Marine Hydrophysical Institute in 2002-2014 are represented. It is shown that this region and the stationary oceanographic platform (SOP) located in its southwestern part constitute a convenient ground for synchronous remote and sub-satellite studies of natural oceanological processes and impact of the coastal anthropogenic pollution sources. The data on hydrochemical characteristics of surface water in the SOP region can be used to study background state of the coastal marine environment as well as influence of intense natural processes (storms and (or) upwellings) upon formation and evolution of hydrochemical and optical structure of surface waters, surface water and atmosphere gas exchange, effect of physical, chemical and biological processes on the sea water quality. Influence of two coastal sources of anthropogenic pollution upon the Blue Bay marine environment was studied using synchronous remote and sub-satellite measurements; the results of these investigations provide additional opportunities for developing and certifying the methods of remote study and monitoring of the coastal marine environment state.Keywords: Blue Bay (Crimea), stationary oceanographic platform, remote study, sub-satellite ground, elements of nutrient cycle, elements of carbon cycle, field data of 2002-2014.
The paper investigates the physicochemical regularities (kinetics and isotherm) of phosphorus and beryllium recovery by sorbents based on polyacrylonitrile (PAN) fiber and Fe(OH)3 obtained by various methods: PAN or pre-hydrolyzed PAN with precipitation of FeCl3 with ammonia, using ready-made or electrochemically generated Na2FeO4, pre-hydrolyzed PAN treated with an alkaline solution of Na2FeO4, as well as their comparison with granular aluminum oxide. The Langmuir, Freudlich and Dubinin–Radushkevich models show high performance of materials for sorption of stable P and Be used as tracers for the release of 7Be, 32P, and 33P from seawater. The obtained kinetic data are processed using kinetic models of intraparticle diffusion and the pseudo-first-order, pseudo-second-order, and Elovich models. Optimal conditions for obtaining sorbents are established, namely, the effect of NaOH concentration at the stages of preparation on the properties of sorbents based on the PAN fiber and Fe(OH)3 obtained by various methods.
Purpose. The study of submarine groundwater discharge is one of the most pressing issues of modern hydrogeology and oceanography. The purpose of the paper is to provide a comprehensive study of the submarine groundwater discharge at Cape Ayia using the hydrological, hydrochemical and radiochemical methods, and to determine the flux of submarine groundwater including the nutrients. Methods and Results. The research werecarried out during the coastal expeditions nearby Cape Ayia on March 24, 2019, and on April 22–24, 2019 during the 106th RV “Professor Vodyanitsky” cruise (April 18 – May 13, 2019). The isotopes 226Ra, 228Ra were extracted using the proprietary MnO2-based fibers. After concentration, the sorbent was squeezed to remove excess water, dried and ashed. Then the ash was placed in the Petri dishes and poured with epoxy resin. Activity of the radionuclides was measured on a low-background semiconductor γ-spectrometer with a detector of high-purity germanium (GC3020) 3 weeks after the resin casting. The activity of 226Ra was determined by the daughter radionuclide 214Pb with the energy 351.9 keV (qγ = 37.2 %), and that of 228Ra – by the daughter 228Ac (T1/2 = 6.1 h, qγ = 27.7 %) with the energy 911.6 keV. The basic elements of the main nutrient cycle were determined photocolorimetrically: mineral phosphorus – by molybdenum blue, silicon – by silicon-molybdenum complex. Nitrates (reduced to nitrites) and nitrites were determined by azo dye; ammonium – by indophenol blue also by the photocolorimetric method. Conclusions. Distribution of hydrophysical, hydrochemical and radiochemical parameters in the water area connected with the known submarine groundwater discharges was studied. The distribution of the 226Ra, 228Ra isotopes was studied for the first time. The data on salinity, specific activity of 226Ra, 228Ra and the nutrients concentration permitted to determine the flows of submarine groundwaters in the Cape Ayia area, which amounted to 8220 ± 1200 m3/day. The anthropogenic contribution to pollution of the groundwater forming the submarine sources is shown.
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