Articoli di riviste: "Hydrochemical modeling"

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Dzombak, David A., e M. Ashraf Ali. "Hydrochemical Modeling of Metal Fate and Transport in Freshwater Environments". Water Quality Research Journal 28, n. 1 (1 febbraio 1993): 7–50. http://dx.doi.org/10.2166/wqrj.1993.003.

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Abstract During the last decade there has been growing interest in the development of hydrochemical models (coupled transport-chemistry-biology models) for better understanding and, eventually, for predicting the fate and transport of metals in freshwater environments. While there has been much discussion of such models and their submodels, and detailed examinations of the mechanistic descriptions and mathematics involved in their formulation, there has been relatively little attention focused on how well they perform in describing field data. This paper provides a look at the state-of-the art in hydrochemical modeling of metal fate and transport in groundwater, riverine and lacustrine systems through review of reported model validation attempts. Focus is on those models that have been applied to describe field data; the degree of success achieved and related factors are examined. Key observations drawn from our review of available hydrochemical models and attempted applications to field data are as follows: (1) most existing models consider steady one-dimensional flow only; (2) most existing models consider only one or a few chemical reaction mechanisms, with sorption-desorption being the most common; (3) local equilibrium is assumed in most models, though kinetic formulations for some chemical processes have been incorporated in some models; and (4) interaction of metals with biota have been considered in only a few models and in a very simplified manner. The most advanced hydrochemical models for metal fate and transport appear to be those for groundwater systems, followed in order by those for rivers and lakes. From a larger perspective, however, hydrochemical models for metals are still at an early stage of development for all freshwater environments.

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Пичугина, Анна Игоревна, e Ирина Геннадьевна Критова. "MODELING OF HYDROCHEMICAL OXIDATION OF HEAZLEWOODITE WITH NITRIC ACID". Вестник Тверского государственного университета. Серия: Химия, n. 3(41) (10 novembre 2020): 65–72. http://dx.doi.org/10.26456/vtchem2020.3.7.

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В работе представлены результаты математического моделирования окислительного растворения хизлевудита в растворах азотной кислоты в условиях равнодоступной поверхности вращающегося диска с применением метода полного факторного эксперимента. Получены и проанализированы зависимости скорости процесса гидрохимического окисления сульфида никеля (W, моль/смс) от продолжительности взаимодействия (τ, с), влияния концентрации азотной кислоты (С, моль/дм), частоты вращения диска (ω, с) и температуры (Т, К). Определены основные кинетические параметры: константа скорости и эффективная энергия активации процесса. Установлены режимы взаимодействия хизлевудита с азотной кислотой, выявлены вероятные лимитирующие стадии взаимодействия. The paper presents the results of mathematical modeling of the oxidative dissolution of hizlewudite in solutions of nitric acid using the rotating disk method and the factor experimental design. The dependences of specific speed of dissolution of sulfide of nickel Nickel sulfide (W, mol/cmc) on the duration of interaction (τ, s), the influence of nitric acid concentration (C, mol/dm), frequencies of rotation disk (ω, s) and temperatures (T, K) were obtained and analyzed. The main kinetic parameters are determined: the rate constant and the activation energy of the process. Established modes of interaction heazlewoodite with nitric acid, identified probable limiting stage of the interaction.

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Yang, Nuan, Guangcai Wang, Zheming Shi, Dan Zhao, Wanjun Jiang, Liang Guo, Fu Liao e Pengpeng Zhou. "Application of Multiple Approaches to Investigate the Hydrochemistry Evolution of Groundwater in an Arid Region: Nomhon, Northwestern China". Water 10, n. 11 (16 novembre 2018): 1667. http://dx.doi.org/10.3390/w10111667.

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Groundwater is a critical water resource for human survival and economic development in arid and semi-arid areas. It is crucial to understand the groundwater circulation and hydrochemical evolution for sustainable management and utilization of groundwater resources in those areas. To this end, an investigation of the hydrochemical characteristics of surface water and groundwater was conducted in Nomhon, an arid area located in the Qaidam Basin, northwest China, by using hydrochemical (major and trace elements) and stable isotopes (δD and δ18O) approaches. Stable isotopes and ion ratios were analyzed to determine the recharge sources, hydrochemistry characteristics, and major hydrogeochemical processes. Meanwhile, inverse geochemistry modeling was applied to quantitatively determine the mass transfer of hydrogeochemical processes. The results showed that groundwater in the study area is mainly recharged by atmospheric precipitation in mountainous areas, and the groundwater in the center of basin might originate from ancient water in cold and humid environments. Along the groundwater flow path, the TDS of groundwater increased gradually from fresh to salty (ranging from 462.50 to 19,604.40 mg/L), and the hydrochemical type changed from Cl·HCO3–Na·Mg·Ca to Cl–Na. Groundwater chemical composition and mass balance modeling results indicated that from alluvial fan to lacustrine plain, the main hydrogeochemical processes changed from the dissolution of halite and albite and the precipitation of dolomite and kaolinite to the dissolution of halite and gypsum, precipitation of calcite, redox (SO42− reduction), and cation exchange. This study would be helpful for water resources management in this area and other similar areas.

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Korshenko, A. N., A. R. Alyautdinov e L. A. Ushakova. "MODELING AND ANALYSIS OF SPATIAL HYDROCHEMICAL STATE OF NEVA BAY WATERS". Proceedings of the International conference “InterCarto/InterGIS” 1, n. 22 (1 gennaio 2016): 120–27. http://dx.doi.org/10.24057/2414-9179-2016-1-22-120-127.

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El Alfy, Mohamed. "Hydrochemical Modeling and Assessment of Groundwater Contamination in Northwest Sinai, Egypt". Water Environment Research 85, n. 3 (1 marzo 2013): 211–23. http://dx.doi.org/10.2175/106143012x13560205145055.

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IWATSUKI, Teruki, Takashi MIZUNO, Takanori KUNIMARU, Yuki AMANO, Tatsuji MATSUZAKI e Takeshi SEMBA. "Expert system of hydrochemical modeling methods for geological disposal of HLW". Journal of Nuclear Fuel Cycle and Environment 19, n. 2 (2012): 51–64. http://dx.doi.org/10.3327/jnuce.19.51.

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Olariu, Andra, e Marin Palcu. "The origin of ammonium in carbonated mineral waters and its underground transport to one production well in Middle Ciuc Depression from Eastern Carpathians". SIMI 2019, SIMI 2019 (20 settembre 2019): 259–78. http://dx.doi.org/10.21698/simi.2019.fp34.

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In many cases in Romania, the mineral waters (in the Neogene Volcanic area of the Eastern Carpathians), especially the carbonate waters, have ammonium in concentration over 0.5 mg/l. The main issue regarding the presence of ammonium is identifying if the concentration is due to the anthropogenic pollution or it is of endogenic origin. The geological, hydrogeological and hydrochemical data analysis resulted in a conceptual model of the aquifer’s spatial position, groundwater movement and mineralization, and ammonium occurrence. The geological and tectonic aspects, aquifer’s recharging, groundwater flow direction, absence of surface pollution sources and correlation of hydrochemical data, all indicate the underground origin of ammonium. The aquifer is generated in pliocene - quaternary granular deposits. In the basement of these granular deposits, in the fracture areas, the groundwater is mixed with carbon dioxide and ammonium emissions, produced in the volcanic chambers. The surface data correlation and the hydrochemical data analysis resulted in the confirmation of the deep ammonium origin. After groundwater flow modeling and ammonium transport simulation, the ammonium plume size and preferential transport directions have been finally elucidated.

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Пичугина, Анна Игоревна, e Дарья Дмитриевна Гончар. "MECHANISM OF HYDROCHEMICAL OXIDATION OF HEAZLEWOODITE IN NITRIC ACID". Вестник Тверского государственного университета. Серия: Химия, n. 4(42) (21 dicembre 2020): 83–89. http://dx.doi.org/10.26456/vtchem2020.4.9.

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В работе представлена математическая модель гидрохимического окисления хизлевудита в разбавленных растворах азотной кислоты. Дана физико-химическая интерпретация основных кинетических характеристик процесса растворения: константа скорости и эффективная энергия активации. Установлены режимы взаимодействия хизлевудита с азотной кислотой, выявлены вероятные лимитирующие стадии. По наблюдаемым кинетическим закономерностям при моделировании процесса, предложен механизм гидрохимического окисления хизлевудита. The paper presents a mathematical model of the hydrochemical oxidation of heazlewoodite in dilute solutions of nitric acid. A physicochemical interpretation of the main kinetic characteristics of the dissolution process is given: the rate constant and the effective activation energy. The modes of interaction of heazlewoodite with nitric acid have been established, and probable limiting stages have been identified. According to the observed kinetic regularities in modeling the process, a mechanism for the hydrochemical oxidation of heazlewoodite has been proposed.

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Raffensperger, J. P., e G. Garven. "The formation of unconformity-type uranium ore deposits; 2, Coupled hydrochemical modeling". American Journal of Science 295, n. 6 (1 giugno 1995): 639–96. http://dx.doi.org/10.2475/ajs.295.6.639.

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Titov, Konstantin V., Alexander Levitski, Pavel K. Konosavski, Andrey V. Tarasov, Yuri T. Ilyin e Michel A. Buès. "Combined application of surface geoelectrical methods for groundwater flow modeling: A case history". GEOPHYSICS 70, n. 5 (settembre 2005): H21—H31. http://dx.doi.org/10.1190/1.2076747.

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Electrical methods [electrical profiling and sounding, induced polarization (IP), and self-potential (SP)], combined with geochemical and hydrochemical surveys, were applied to characterize shallow sediments at a site contaminated by oil-related brines. The site is located within the Romashkinskoye oil field (Tatarstan Republic, Russian Federation). Results of geochemical and hydrochemical surveys, as well as those of electrical profiling, revealed no individual haloes of contaminant in the soil and groundwater, which suggests that the entire site is contaminated. Vertical electrical IP soundings (VES-IP) allowed us to obtain the stratigraphic characteristics of the site and to distinguish a shallow aquifer among clayey aquitards. Interpretation of SP data on the basis of forward numerical modeling helped us to develop a groundwater-flow model of the site. To reduce ambiguities, we kept fixed the values of layer resistivity derived from the inverted VES-IP data. Boundary conditions on water head and water flow were based on drilling and sampling data. We varied only the values of hydraulic conductivity to fit the calculated SP values to the measured SP values. We found a strong misfit between the measured and calculated SP values for the one-aquifer model. By inferring a second, deeper-seated aquifer, we computed a two-aquifer model that produced a satisfactory SP fit.

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Beretta, Giovanni Pietro, Monica Avanzini, Tomaso Marangoni, Marino Burini, Giacomo Schirò, Jacopo Terrenghi e Gaetano Vacca. "Groundwater modeling of the withdrawal sustainability of Cannara artesian aquifer (Umbria, Italy)". Acque Sotterranee - Italian Journal of Groundwater 7, n. 3 (25 settembre 2018): 47–60. http://dx.doi.org/10.7343/as-2018-333.

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The Cannara aquifer (Umbria, Italy) has been known for more than a century, and is one of the main drinking water supplies in the Umbria Region. In the beginning it was used for irrigation purposes, since this area was mainly agricultural up to the 1960s. The groundwater—exploited by Umbra Acque S.p.A. (a Company supplying drinking water)—is 150 m under ground level and is contained in a porous confined aquifer, which originally had artesian characteristics. Exploitation of 200–300 l/s with nine wells caused a reduction of piezometric level, maintaining the confined aquifer conditions, except for a very short period during which the aquifer was depressurised by drought, and for increase of emergency withdrawals replacing other water supplies (from springs) for drinking purposes. The occasional presence of iron and ammonium ions confirms the confinement of the groundwater and their hydrochemical facies in a redox environment, while in nearby areas and shallow aquifers anthropogenic contaminants (nitrates and chlorinated solvents) are reported. For the protection of this aquifer of strategic interest (the most important well field in Umbria), all hydrological and hydrochemical data available have been reviewed, and the aquifer recharge studied. Sustainable rates of withdrawal, and groundwater protection areas have been identified using a numerical flow model. Further action for monitoring groundwater of both shallow and artesian aquifers, together with well-revamping, have been proposed.

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Siddique, Jamil, Jin Menggui, Munir H. Shah, Asfandyar Shahab, Faisal Rehman e Umair Rasool. "Integrated Approach to Hydrogeochemical Appraisal and Quality Assessment of Groundwater from Sargodha District, Pakistan". Geofluids 2020 (29 dicembre 2020): 1–15. http://dx.doi.org/10.1155/2020/6621038.

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Hydrochemical characteristics and aquifer properties present a better understanding of the mitigation of groundwater pollution, which has become one of the leading environmental concerns and threats to the sustainable ecosystem. Seventy-seven groundwater samples were collected from Sargodha District (Pakistan) and characterized for their physical and chemical properties. The analytical data were processed for the evaluation of the processes that control the groundwater chemistry using various drinking and agricultural indices with statistical and hydrochemical modeling. The predominant hydrochemical type was found to be Ca-HCO3 type, followed by Na-HCO3 and Mg-Ca-Cl types. The present study showed that the main factors controlling the groundwater chemistry were the prevalent rock dominance alongside the weathering of silicates, solubilization of carbonates, and cation exchange processes. Entropy water quality index (EWQI) revealed that 6.51% represented “poor water,” while 7.79% were considered “extremely poor” for drinking purposes. However, USSL classification, Wilcox diagram, and other agricultural indices (RCS, SAR, %Na, MH, PI, and PS) showed that the majority of the samples were classified as suitable for irrigation purpose. However, 16% of the samples for %Na and 24% of the samples for MH were not suitable for agricultural purposes. Overall, the groundwater quality was affected by the anthropogenic stress in the study area.

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Wästeby, Niklas, Alasdair Skelton, Elin Tollefsen, Margareta Andrén, Gabrielle Stockmann, Lillemor Claesson Liljedahl, Erik Sturkell e Magnus Mörth. "Hydrochemical monitoring, petrological observation, and geochemical modeling of fault healing after an earthquake". Journal of Geophysical Research: Solid Earth 119, n. 7 (luglio 2014): 5727–40. http://dx.doi.org/10.1002/2013jb010715.

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Mohebbi Tafreshi, Ghazaleh, e Amin Mohebbi Tafreshi. "Statistical approaches and hydrochemical modeling of groundwater in the Golpayegan Plain aquifer, Iran". Modeling Earth Systems and Environment 6, n. 4 (6 giugno 2020): 2391–404. http://dx.doi.org/10.1007/s40808-020-00822-w.

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Sasamoto, Hiroshi, Mikazu Yui e Randolph C. Arthur. "Hydrochemical characteristics and groundwater evolution modeling in sedimentary rocks of the Tono mine, Japan". Physics and Chemistry of the Earth, Parts A/B/C 29, n. 1 (gennaio 2004): 43–54. http://dx.doi.org/10.1016/j.pce.2003.11.003.

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Chen, Kouping, e Jiu Jimmy Jiao. "Modeling freshening time and hydrochemical evolution of groundwater in coastal aquifers of Shenzhen, China". Environmental Earth Sciences 71, n. 5 (27 novembre 2013): 2409–18. http://dx.doi.org/10.1007/s12665-013-2641-3.

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Sha, Jian, Xue Li e Jingjing Yang. "Estimation of Watershed Hydrochemical Responses to Future Climate Changes Based on CMIP6 Scenarios in the Tianhe River (China)". Sustainability 13, n. 18 (9 settembre 2021): 10102. http://dx.doi.org/10.3390/su131810102.

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The impacts of future climate changes on watershed hydrochemical processes were assessed based on the newest Shared Socioeconomic Pathways (SSP) scenarios in Coupled Model Intercomparison Project Phase 6 (CMIP6) in the Tianhe River in the middle area of China. The monthly spatial downscaled outputs of General Circulation Models (GCMs) were used, and a new Python procedure was developed to batch pick up site-scale climate change information. A combined modeling approach was proposed to estimate the responses of the streamflow and Total Dissolved Nitrogen (TDN) fluxes to four climate change scenarios during four future periods. The Long Ashton Research Station Weather Generator (LARS-WG) was used to generate synthetic daily weather series, which were further used in the Regional Nutrient Management (ReNuMa) model for scenario analyses of watershed hydrochemical process responses. The results showed that there would be 2–3% decreases in annual streamflow by the end of this century for most scenarios except SSP 1-26. More streamflow is expected in the summer months, responding to most climate change scenarios. The annual TDN fluxes would continue to increase in the future under the uncontrolled climate scenarios, with more non-point source contributions during the high-flow periods in the summer. The intensities of the TDN flux increasing under the emission-controlled climate scenarios would be relatively moderate, with a turning point around the 2070s, indicating that positive climate policies could be effective for mitigating the impacts of future climate changes on watershed hydrochemical processes.

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Dar’ya Ivanovna, PETROVA. "Technogenic transformation of the underground hydrosphere of Kazan. Lower Kazanian aquifer complex". NEWS of the Ural State Mining University, n. 2 (15 giugno 2021): 114–22. http://dx.doi.org/10.21440/2307-2091-2021-2-114-122.

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Relevance. By the beginning of the XXI century, the growth of cities, population concentration and the revival of industrial production led to an intense technogenic pressure on the underground hydrosphere. In ecological and hydrogeological studies, it becomes necessary to conduct monitoring observations of groundwater based on GIS technologies. Purpose of the work: study of the hydrogeochemical characteristics of underground waters of the aquiferous lower Kazanian carbonate-terrigenous complex to provide Kazan with high-quality drinking water from protected underground sources. Research methodology. Hydrochemical data from geological reports and archival materials for the period from 1960 years to 2019 years were used. Methods of mathematical statistics (basic, cluster and factor analyzes) made it possible to differentiate into natural and man-made components. Geographic information modeling using the “ArcGisMap” package showed the spatial variability of the main components in the waters of the Neogene complex at the turn of the 20th and 21st centuries. Conclusion. The hydrochemical parameters of the aquiferous lower Kazanian complex are assessed as favorable, since practically all the main components do not exceed the MPC values for drinking water.

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Glok Galli, M., D. E. Martínez e E. E. Kruse. "The carbon budget of a large catchment in the Argentine Pampa plain through hydrochemical modeling". Science of The Total Environment 493 (settembre 2014): 649–55. http://dx.doi.org/10.1016/j.scitotenv.2014.06.032.

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Olofinlade, W. S., S. O. Daramola e O. F. Olabode. "Hydrochemical and statistical modeling of groundwater quality in two constrasting geological terrains of southwestern Nigeria". Modeling Earth Systems and Environment 4, n. 4 (15 giugno 2018): 1405–21. http://dx.doi.org/10.1007/s40808-018-0486-1.

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Bergström, S., B. Carlsson, G. Sandberg e L. Maxe. "Integrated Modelling of Runoff, Alkalinity, and pH on a Daily Basis". Hydrology Research 16, n. 2 (1 aprile 1985): 89–104. http://dx.doi.org/10.2166/nh.1985.0008.

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Based on the experience from runoff and groundwater recharge simulation a model system has been developed for terrestrial, hydrochemical, and hydrological simulations. The system emphasizes the role of temporary or long term storage in the aquifers of a basin and, separately, accounts for each rainfall or snowmelt event from its entrance into the ground until mixing in the river system. The model is primarily intended for simulation of natural short term variations in alkalinity and pH in running waters. The hydrochemical processes are modelled in a semi-empirical way without assumption of complete hydrochemichal mass-balance. In the paper a brief hydrochemical background is given, and a model with two alternative hydrochemical sub-structures is described. Examples of daily simulations of runoff alkalinity and pH from three different basins are given.

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Moran-Ramirez, Janete, e Jose Alfredo Ramos-Leal. "The VISHMOD Methodology with Hydrochemical Modeling in Intermountain (Karstic) Aquifers: Case of the Sierra Madre Oriental, Mexico". Journal of Geography and Geology 6, n. 2 (7 maggio 2014): 132. http://dx.doi.org/10.5539/jgg.v6n2p132.

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Hydrogeochemistry can be studied qualitatively using graphics such as scatter plots and Piper, Durov, and Schoeller diagrams, among others, and quantitatively by applying mass balance mixing models. The VISHMOD methodology (Virtual Samples in Hydrochemical Modeling) combines these two forms of hydrogeochemical characterizations. It is performed by applying hydrogeochemical modeling to virtual samples. This method makes standardization and control possible in order to demonstrate the extent to which a model is able to reproduce field measurements. Therefore, hydrogeochemical models of hydrogeological systems must be calibrated. This methodology was applied to carbonate and homogeneous media in the Sierra Madre Oriental in Mexico. Using the VISHMOD methodology in this region resulted in the classification of the water type as calcium bicarbonate (Ca-HCO3), representing a ternary mixture in which 45.5% was associated with local flow, 38.5% to intermediate flow and 16.5% to water-rock interaction. The main mineral phases were saturated calcite and sub-saturated dolomite, both from limestone contained in the Tamaulipas Formation.

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Pinault, J. L., V. Plagnes, L. Aquilina e M. Bakalowicz. "Inverse modeling of the hydrological and the hydrochemical behavior of hydrosystems: Characterization of Karst System Functioning". Water Resources Research 37, n. 8 (agosto 2001): 2191–204. http://dx.doi.org/10.1029/2001wr900018.

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Varotsos, Costas A., Vladimir F. Krapivin, Ferdenant A. Mkrtchyan e Yong Xue. "Optical Spectral Tools for Diagnosing Water Media Quality: A Case Study on the Angara/Yenisey River System in the Siberian Region". Land 10, n. 4 (27 marzo 2021): 342. http://dx.doi.org/10.3390/land10040342.

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This paper presents the results of spectral optical measurements of hydrochemical characteristics in the Angara/Yenisei river system (AYRS) extending from Lake Baikal to the estuary of the Yenisei River. For the first time, such large-scale observations were made as part of a joint American-Russian expedition in July and August of 1995, when concentrations of radionuclides, heavy metals, and oil hydrocarbons were assessed. The results of this study were obtained as part of the Russian hydrochemical expedition in July and August, 2019. For in situ measurements and sampling at 14 sampling sites, three optical spectral instruments and appropriate software were used, including big data processing algorithms and an AYRS simulation model. The results show that the water quality in AYRS has improved slightly due to the reasonably reduced anthropogenic industrial impact. Chemical concentrations in water have been found to vary along the Angara River depending on the location of the dams. The results of in situ measurements and modeling evaluations are given. To overcome the uncertainties in the data caused by the large monitoring area, it is recommended to use the combined AYRS simulation model and the universal 8-channel spectrophotometer installed on a fixed platform for continuous monitoring.

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Peiyue, Li, Qian Hui e Wu Jianhua. "Hydrochemical Formation Mechanisms and Quality Assessment of Groundwater with Improved TOPSIS Method in Pengyang County Northwest China". E-Journal of Chemistry 8, n. 3 (2011): 1164–73. http://dx.doi.org/10.1155/2011/251918.

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Inverse geochemical modeling was used in this paper to quantitatively study the formation mechanisms of groundwater in Pengyang County, China. An improved TOPSIS method based on entropy weight was used to perform groundwater quality assessment in this area. The assessment results show that the groundwater in the study area is fit for human consumption and the high concentrations of some elements can be attributed to the strong water-rock interactions. The inverse geochemical modeling reveals that the dominant reactions in different parts of the study area are different. In the south part of the study area, the precipitation of sodium montmorillonite, calcite and the dissolution of gypsum, fluorite, halite, albite and dolomite as well as CO2dissolution and cation exchange are the major water-rock interactions, while in the north part, the leading reactions are the precipitation of gypsum, dolomite, sodium montmorillonite, fluorite, the dissolution of calcite and albite and the CO2emission and cation exchange are also important. All these reactions are influenced by the initial aquatic environment and hydrodynamic conditions of the flow path.

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Pinault, J. L., H. Pauwels e C. Cann. "Inverse modeling of the hydrological and the hydrochemical behavior of hydrosystems: Application to nitrate transport and denitrification". Water Resources Research 37, n. 8 (agosto 2001): 2179–90. http://dx.doi.org/10.1029/2001wr900017.

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Delsman, J. R., K. R. M. Hu-a-ng, P. C. Vos, P. G. B. de Louw, G. H. P. Oude Essink, P. J. Stuyfzand e M. F. P. Bierkens. "Paleo-modeling of coastal saltwater intrusion during the Holocene: an application to the Netherlands". Hydrology and Earth System Sciences 18, n. 10 (2 ottobre 2014): 3891–905. http://dx.doi.org/10.5194/hess-18-3891-2014.

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Abstract. Coastal groundwater reserves often reflect a complex evolution of marine transgressions and regressions, and are only rarely in equilibrium with current boundary conditions. Understanding and managing the present-day distribution and future development of these reserves and their hydrochemical characteristics therefore requires insight into their complex evolution history. In this paper, we construct a paleo-hydrogeological model, together with groundwater age and origin calculations, to simulate, study and evaluate the evolution of groundwater salinity in the coastal area of the Netherlands throughout the last 8.5 kyr of the Holocene. While intended as a conceptual tool, confidence in our model results is warranted by a good correspondence with a hydrochemical characterization of groundwater origin. Throughout the modeled period, coastal groundwater distribution never reached equilibrium with contemporaneous boundary conditions. This result highlights the importance of historically changing boundary conditions in shaping the present-day distribution of groundwater and its chemical composition. As such, it acts as a warning against the common use of a steady-state situation given present-day boundary conditions to initialize groundwater transport modeling in complex coastal aquifers or, more general, against explaining existing groundwater composition patterns from the currently existing flow situation. The importance of historical boundary conditions not only holds true for the effects of the large-scale marine transgression around 5 kyr BC that thoroughly reworked groundwater composition, but also for the more local effects of a temporary gaining river system still recognizable today. Model results further attest to the impact of groundwater density differences on coastal groundwater flow on millennial timescales and highlight their importance in shaping today's groundwater salinity distribution. We found free convection to drive large-scale fingered infiltration of seawater to depths of 200 m within decades after a marine transgression, displacing the originally present groundwater upwards. Subsequent infiltration of fresh meteoric water was, in contrast, hampered by the existing density gradient. We observed discontinuous aquitards to exert a significant control on infiltration patterns and the resulting evolution of groundwater salinity. Finally, adding to a long-term scientific debate on the origins of groundwater salinity in Dutch coastal aquifers, our modeling results suggest a more significant role of pre-Holocene groundwater in the present-day groundwater salinity distribution in the Netherlands than previously recognized. Though conceptual, comprehensively modeling the Holocene evolution of groundwater salinity, age and origin offered a unique view on the complex processes shaping groundwater in coastal aquifers over millennial timescales.

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Gkiougkis, Ioannis, Christos Pouliaris, Fotios-Konstantinos Pliakas, Ioannis Diamantis e Andreas Kallioras. "Conceptual and Mathematical Modeling of a Coastal Aquifer in Eastern Delta of R. Nestos (N. Greece)". Hydrology 8, n. 1 (29 gennaio 2021): 23. http://dx.doi.org/10.3390/hydrology8010023.

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In this paper, the development of the conceptual and groundwater flow model for the coastal aquifer system of the alluvial plain of River Nestos (N. Greece), that suffers from seawater intrusion due to over-pumping for irrigation, is analyzed. The study area is a typical semi-arid hydrogeologic environment, composed of a multi-layer granular aquifers that covers the eastern coastal delta system of R. Nestos. This study demonstrates the results of a series of field measurements (such as geophysical surveys, hydrochemical and isotopical measurements, hydro-meteorological data, land use, irrigation schemes) that were conducted during the period 2009 to 2014. The synthesis of the above resulted in the development of the conceptual model for this aquifer system, that formed the basis for the application of the mathematical model for simulating groundwater flow. The mathematical modeling was achieved using the finite difference method after the application of the USGS code MODFLOW-2005.

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Hussien, Bayan Muhie. "Modeling the impact of groundwater depletion on the hydrochemical characteristic of groundwater within Mullusi carbonate aquifer-west Iraq". Environmental Earth Sciences 70, n. 1 (14 dicembre 2012): 453–70. http://dx.doi.org/10.1007/s12665-012-2139-4.

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Fu, Changchang, Wenjing Zhang, Shengyu Zhang, Xiaosi Su e Xueyu Lin. "Identifying key hydrochemical processes in a confined aquifer of an arid basin using multivariate statistical analysis and inverse modeling". Environmental Earth Sciences 72, n. 1 (7 maggio 2014): 299–310. http://dx.doi.org/10.1007/s12665-014-3290-x.

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Scanlon, Todd M., Jeff P. Raffensperger e George M. Hornberger. "Modeling transport of dissolved silica in a forested headwater catchment: Implications for defining the hydrochemical response of observed flow pathways". Water Resources Research 37, n. 4 (aprile 2001): 1071–82. http://dx.doi.org/10.1029/2000wr900278.

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Kim, Ji-Hyun, Kyoung-Ho Kim, Nguyen Thi Thao, Bayartungalag Batsaikhan e Seong-Taek Yun. "Hydrochemical assessment of freshening saline groundwater using multiple end-members mixing modeling: A study of Red River delta aquifer, Vietnam". Journal of Hydrology 549 (giugno 2017): 703–14. http://dx.doi.org/10.1016/j.jhydrol.2017.04.040.

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Wolford, Ross A., e Roger C. Bales. "Hydrochemical modeling of Emerald Lake watershed, Sierra Nevada, California: Sensitivity of stream chemistry to changes in fluxes and model parameters". Limnology and Oceanography 41, n. 5 (luglio 1996): 947–54. http://dx.doi.org/10.4319/lo.1996.41.5.0947.

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Choi, Byoung-Young, Seong-Taek Yun, Kyoung-Ho Kim, Hyeon-Su Choi, Gi-Tak Chae e Pyeong-Koo Lee. "Geochemical modeling of CO2–water–rock interactions for two different hydrochemical types of CO2-rich springs in Kangwon District, Korea". Journal of Geochemical Exploration 144 (settembre 2014): 49–62. http://dx.doi.org/10.1016/j.gexplo.2014.02.009.

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35

Kozhin, V. N., A. V. Grishagin, O. S. Fedotkina, D. V. Kashaev e O. V. Gladunov. "Computer modeling software for applied engineering analysis in the field of assessing the hydrochemical processes of oil and gas production". Neftyanoe khozyaystvo - Oil Industry, n. 8 (2021): 81–83. http://dx.doi.org/10.24887/0028-2448-2021-8-81-83.

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Masoud, Alaa A., e Ali A. Aldosari. "Groundwater Quality Assessment of a Multi-Layered Aquifer in a Desert Environment: A Case Study in Wadi ad-Dawasir, Saudi Arabia". Water 12, n. 11 (28 ottobre 2020): 3020. http://dx.doi.org/10.3390/w12113020.

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Sustainable management of groundwater in desert environments dictates better knowledge of the quality status and the controlling processes. To this end, an integrated analysis of hydrochemical and statistical assessment was carried out for 692 groundwater samples collected from the multi-layered aquifer system in Wadi ad-Dawasir area (Saudi Arabia). The four water-bearing formations arranged upwards, namely Lower Wajid, Upper Wajid, Khuff-Kumdah, and Quaternary, were investigated. The prime objective was to delineate the baseline conditions and the dominant process controlling the groundwater evolution that can help make resource management better. We used fifteen indicators, namely the total dissolved solid (TDS), total hardness, Eh, pH, temperature °C, turbidity, Fe2+, dissolved oxygen (DO), NH4, HCO3−, NO3−, F, NO2−, PO42−, and SiO2. Descriptive statistics, violation of the international standards, geostatistical modeling, and factorial analyses (FA) were performed. Geologic, soil, topographic, and climatic factors controlling the quality were investigated. The Quaternary aquifer was the most polluted by TDS, total hardness, NO3−, SiO2, Fe2+, F, and HCO3−. Khuff-Kumdah showed largest means of DO and NH4. Upper Wajid was the largest in NO2−. Lower Wajid proved largest in PO42−. Violation of the international standards clarified largest emergence of the pH for the Lower Wajid; Fe2+ and NO3− for the Upper Wajid; and total hardness, TDS, Fluoride, turbidity, and NH4 for the Quaternary aquifer. Rock interaction and evaporation are the dominant processes that contributed largely to the hydrochemical evolution of the groundwater. FA distinguished six main factors that explained for over 60.8% of the total groundwater quality variation lead byF1 (44.23%) that clarified strong positive loads of TDS (0.98), total hardness (0.95), nitrate NO3− (0.84), turbidity (0.78), NH4 (0.67), moderately loaded by fluoride (0.47), and Fe2+ (0.31).

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Krapivin, Vladimir F., Costică Nitu, Ferdenant A. Mkrtchyan, Vladimir Yu Soldatov e Anda Sabena Dobrescu. "INFORMATION-INSTRUMENTAL TOOLS OF MICROWAVE AND OPTICAL ENVIRONMENTAL MONITORING". Scientific Bulletin of Electrical Engineering Faculty 18, n. 1 (1 aprile 2018): 11–18. http://dx.doi.org/10.1515/sbeef-2017-0016.

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Abstract Informational capabilities of microwave and optical tools for environmental monitoring are assessed when they are located on the mobile platforms. This paper presents new approach to the combined use of microwave and optical sensors as basic elements of environmental monitoring system architecture oriented on the registration of information about characteristics of hydrological and hydrochemical objects. Geoecological in-formation-modeling system (GIMS) is proposed as the GIS generalization with regard to the solution of series of the tasks arising in the agriculture, water quality assessment and operational diagnostics of stressful natural processes. Algorithms and models are characterized to be as the GIMS components that realize the decision making procedures providing the monitoring regime optimization and reconstruction of spatial image of the controlled environmental object using anisotropic data fluxes. Functional characteristics of several mobile platforms equipped by microwave radiometers are given as tools for the monitoring of hydrological objects. Two optical instruments are represented and their functions are characterized.

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Kozak, V., A. Tovmachenko e M. Gertsiuk. "Methodological aspects of assessment of the state of chemical pollution and water quality of surface waters in Ukraine". Zurnal Hromatograficnogo tovaristva 20, n. 66 (16 ottobre 2020): 33–61. http://dx.doi.org/10.15407/zht2020.66.033.

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The main sources of chemical pollution of surface water bodies of Ukraine are shown and it is noted that the ecosystem of the environment and water resources, being under constant man-caused load, tend to steadily deteriorate the ecological condition. Methods for assessing the quality of surface waters using the maximum allowable concentrations of harmful substances in water and a comprehensive assessment of the ecological status of surface water by integrated hydrochemical parameters are described. International approaches to the assessment of the state of surface water bodies are considered. It is noted that the most complete information on the state of the aquatic ecosystem can be obtained using a set of physicochemical and biological parameters. There are shortcomings in the monitoring of organic micro-pollutants in surface waters. The analysis of the international experience of determination of water quality and parameters of toxicological action of organic micro-pollutants with application of chemo-informative methods for modeling of an ecological condition of water systems is carried out.

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Azevedo da Silva, Talita, Fátima Ferreira do Rosário e Gerson Cardoso da Silva Júnior. "Environmental isotopes and hydrochemical tracers applied to hydrogeological conceptual modeling of the southwest portion of the Amazon Aquifer System (Acre, Brazil)". Applied Geochemistry 120 (settembre 2020): 104670. http://dx.doi.org/10.1016/j.apgeochem.2020.104670.

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40

Slimani, Rabia, Abdelhamid Guendouz, Fabienne Trolard, Adnane Souffi Moulla, Belhadj Hamdi-Aïssa e Guilhem Bourrié. "Identification of dominant hydrogeochemical processes for groundwaters in the Algerian Sahara supported by inverse modeling of chemical and isotopic data". Hydrology and Earth System Sciences 21, n. 3 (21 marzo 2017): 1669–91. http://dx.doi.org/10.5194/hess-21-1669-2017.

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Abstract. Unpublished chemical and isotopic data taken in November 1992 from the three major Saharan aquifers, namely the Continental Intercalaire (CI), the Complexe Terminal (CT) and the phreatic aquifer (Phr), were integrated with original samples in order to chemically and isotopically characterize the largest Saharan aquifer system and investigate the processes through which groundwaters acquire their mineralization. Instead of classical Debye–Hückel extended law, a specific interaction theory (SIT) model, recently incorporated in PHREEQC 3.0, was used. Inverse modeling of hydrochemical data constrained by isotopic data was used here to quantitatively assess the influence of geochemical processes: at depth, the dissolution of salts from the geological formations during upward leakage without evaporation explains the transitions from CI to CT and to a first end member, a cluster of Phr (cluster I); near the surface, the dissolution of salts from sabkhas by rainwater explains another cluster of Phr (cluster II). In every case, secondary precipitation of calcite occurs during dissolution. All Phr waters result from the mixing of these two clusters together with calcite precipitation and ion exchange processes. These processes are quantitatively assessed by the PHREEQC model. Globally, gypsum dissolution and calcite precipitation were found to act as a carbon sink.

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Manakos, Antonios, Maria Ntona, Nerantzis Kazakis e Konstantinos Chalikakis. "Enhanced Characterization of the Krania–Elassona Structure and Functioning Allogenic Karst Aquifer in Central Greece". Geosciences 9, n. 1 (27 dicembre 2018): 15. http://dx.doi.org/10.3390/geosciences9010015.

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The present study highlights the importance of geological, hydrogeological, and hydrogeochemical characterization of a karst aquifer in building a conceptual model of the system. The karst system of Krania–Elassona in central Greece was chosen for this application. Hydrogeological research included geological mapping and hydrogeological analysis. Additionally, hydrochemical analysis of water samples was performed in boreholes, rivers, and the system’s main spring. The Krania–Elassona aquifer consists of three horizons of marbles and is characterized by mature karstification. The karst aquifer is characterized by allogenic recharge mainly from the River Deskatis that accounts for up to 92% of the total flow. Groundwater and spring water are generally characterized as good quality and are suitable for irrigation and domestic use. The water type of the spring water is classified as Mg-HCO3. The application of a SARIMA (Seasonal Autoregressive Integrated Moving Average Model) model verified the conceptual model and successfully simulated spring discharge for a two-year period. The results of this study highlight the importance of basic hydrogeological research and the initial conceptualization of karst systems in reliably assessing groundwater vulnerability and modeling.

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Frenierre, Jeff La, e Bryan G. Mark. "A review of methods for estimating the contribution of glacial meltwater to total watershed discharge". Progress in Physical Geography: Earth and Environment 38, n. 2 (30 gennaio 2014): 173–200. http://dx.doi.org/10.1177/0309133313516161.

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Glaciers store water over a range of temporal scales with important implications for downstream human and natural systems. Assessment of the contribution of glacial meltwater runoff to total watershed discharge is an essential part of climate change risk assessment and sustainable water management in glacierized watersheds. Over the past decade, a range of techniques for quantifying the proportional contribution of glacial meltwater has been presented in the scientific literature. Here we examine five different methodological approaches: direct discharge measurement, glaciological approaches, hydrological balance equations, hydrochemical tracers, and hydrological modeling. After a brief summary of the role of glaciers in watershed hydrology, we evaluate each approach, with regard to their respective data requirements, assumptions, and associated uncertainties. Next, we discuss factors that researchers must consider in deciding upon a particular methodological approach, then conclude with a discussion of future research needs. We underscore the need for expanded meteorological, hydrological, and glaciological monitoring networks in glacierized watersheds worldwide, for more comprehensive assessment of uncertainty and for better integration of research with the specific needs of watershed stakeholders.

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Gubareva, T. S., B. I. Gartsman, V. V. Shamov, T. N. Lutsenko, A. G. Boldeskul, N. K. Kozhevnikova e S. Yu Lupakov. "Runoff components of small catchments in Sikhote-Alin: summarizing the results of field measurements and tracer modeling". Izvestiya Rossiiskoi akademii nauk. Seriya geograficheskaya, n. 6 (17 dicembre 2019): 126–40. http://dx.doi.org/10.31857/s2587-556620196126-140.

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The article summarizes results of the systematic study of the streamflow formation of two small catchments in the upper part of the Ussuri River. The study was carried out by the hydrograph separation technique (using detailed data of the hydrochemical and hydrological monitoring) and the use of a tracer mixing model in conjunction with EMMA. Performed in the period from 2011 to 2016 the studies allowed to calculate the river runoff components of the summer-autumn period at 3 gauge-stations and evaluate their mutual dynamics at different time scales. It is shown that in the case of landscape uniformity of the catchment (the Medvezhiy Creek), the river flow can be represented as a result of 3 sources mixing. This, the most common, scheme for the hydrograph separation includes following sources: a direct rainfall flow, an organic soil water component, and an underground baseflow. If the catchments landscape structure is clearly heterogeneous (the Elovy Creek), the river flow can be represented as a result of 4 sources mixing. In this case, the fourth source appears as a result of the separation of soil water component into individual components organic and mineral. This separation is due to the spread in the basin of the cold upper belt of fir-spruce forests, whose soils are characterized by a lower rate of organic matter destruction and a deeper illuviation process of DOC. Statistically significant dependencies of the some runoff components proportions against river discharges were identified, systematization of which makes them promising for practice in hydrological monitoring and forecasting.

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MASOUD, Alaa A. "Trends and Causes of Deterioration in the Shallow Groundwater Conditions in an Arid Agriculture Area through GIS-based Spatial Hydrochemical and Hydrodynamics Modeling". GEOINFORMATICS 24, n. 1 (2012): 3–13. http://dx.doi.org/10.6010/geoinformatics.24.3.

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45

Delsman, J. R., K. R. M. Hu-a-ng, P. C. Vos, P. G. B. de Louw, G. H. P. Oude Essink, P. J. Stuyfzand e M. F. P. Bierkens. "Palaeo-modeling of coastal salt water intrusion during the Holocene: an application to the Netherlands". Hydrology and Earth System Sciences Discussions 10, n. 11 (13 novembre 2013): 13707–42. http://dx.doi.org/10.5194/hessd-10-13707-2013.

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Abstract. Management of coastal fresh groundwater reserves requires a thorough understanding of the present-day groundwater salinity distribution and its possible future development. However, coastal groundwater often still reflects a complex history of marine transgressions and regressions, and is only rarely in equilibrium with current boundary conditions. In addition, the distribution of groundwater salinity is virtually impossible to characterize satisfactorily, complicating efforts to model and predict coastal groundwater flow. A way forward may be to account for the historical development of groundwater salinity when modeling present-day coastal groundwater flow. In this paper, we construct a palaeo-hydrogeological model to simulate the evolution of groundwater salinity in the coastal area of the Netherlands throughout the Holocene. While intended as a perceptual tool, confidence in our model results is warranted by a good correspondence with a hydrochemical characterization of groundwater origin. Model results attest to the impact of groundwater density differences on coastal groundwater flow on millennial timescales and highlight their importance in shaping today's groundwater salinity distribution. Not once reaching steady-state throughout the Holocene, our results demonstrate the long-term dynamics of salinity in coastal aquifers. This stresses the importance of accounting for the historical evolution of coastal groundwater salinity when modeling present-day coastal groundwater flow, or when predicting impacts of e.g. sea level rise on coastal aquifers. Of more local importance, our findings suggest a more significant role of pre-Holocene groundwater in the present-day groundwater salinity distribution in the Netherlands than previously recognized. The implications of our results extend beyond understanding the present-day distribution of salinity, as the proven complex history of coastal groundwater also holds important clues for understanding and predicting the distribution of other societally relevant groundwater constituents.

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Borcia, Constantin. "Aspects on the History of Observations and Measurements in the Black Sea Coastal Zone, Rehabilitation Projects and Marine Modeling Issues". Ovidius University Annals of Constanta - Series Civil Engineering 20, n. 1 (1 dicembre 2018): 31–42. http://dx.doi.org/10.2478/ouacsce-2018-0003.

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Abstract Over time, the content, scope and objectives of hydrological research in the Romanian Black Sea coastal area varied according to the state of society development, technology development and financial resources. Along with the activities of capitalizing on natural resources, water use, river and sea navigation, there have been demands for knowledge of the water regime and the interaction between the resource potential and the characteristics of the hydrological regime. As a result, hydrographic and hydrological research was started and developed in the Black Sea coastal zone. These researches developed in the first half of the nineteenth century, and then continued throughout this century and later in the twentieth century, with interruptions caused by the two world wars. Among the important activities that have taken place over time, there have been hydro-technical works. The design and elaboration of the projects of these works were based on the knowledge of the hydrographic and hydrological characteristics of the Black Sea coastal zone. This knowledge has evolved over time so that there is currently an important pool of data and information related to the hydrological, morphological, hydrochemical, hydrobiological characteristics of the water bodies mentioned. The paper presents briefly the most important moments of the history of the monitoring activity carried out over time in the Black Sea coastal zone, the types of coastal and transitional waters in Romania, coastal rehabilitation projects of the Black Sea, hydrological features, the structure of the marine complex model pom / ersem III) BREG / BSHELF.

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Gopchenko, E. D., J. S. Medvedєva e J. A. Makedonskay. "Water balance systems of lakes Yalpuh – Kugurluy (in the period 2006-2014 yy.)". Ukrainian hydrometeorological journal, n. 16 (29 ottobre 2017): 176–83. http://dx.doi.org/10.31481/uhmj.16.2015.23.

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Introduction. Violation of natural water exchange in the lake Yalpug - Kugurluy led to the deterioration of water quality in lakes and their shoaling and silting of lakes and overgrown with reeds. Purpose. Water system study mode lakes Yalpug - Kugurluy based on water balance equation and the definition and analysis components of the water balance equation system oz.Yalpuh - Kugurluy. Based on this analysis needs to develop to offer optimal functioning oz.Yalpuh - Kugurluy, in terms of its tiered and hydrochemical regimes as well as perform mathematical modeling of reservoir operation in different administrative actions. Methods. The article used the methods of analysis in theory, the method of water balance. Results. Established that the greatest impact on the water regime of lakes in incoming parts are precipitation, the expenditure - the evaporation from the water surface of lakes and water exchange мagee system of lakes Yalpug - Kugurluy and Danube river. Conclusion. It should be a more detailed investigation of the water regime of lakes, the adoption of recommendations for the improvement of water exchange in lakes as well as improve the quality of water for agricultural purposes.

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Gruzinov, V. M., N. N. Dyakov, I. V. Mezenceva, Yu A. Malchenko, N. V. Zhohova e A. N. Korshenko. "Sources of coastal waters pollution near Sevastopol". Океанология 59, n. 4 (17 settembre 2019): 579–90. http://dx.doi.org/10.31857/s0030-1574594579-590.

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The results of current ecological investigations of marine waters in Sevastopol region are presented. The main sources of water pollution described for Sevastopol Bay and other part of coastal line from cup Lukull till cup Foros were described. The position of Waste Water Treatment Plant underwater outlets, the volume of waste-waters discharges and the degree of their purification were estimated. With the help of the side-scan sonar, the state of the heads of the sewage treatment plants in the region was examined. The features of the vertical distribution of hydrological and hydrochemical characteristics are shown. The preliminary estimation of the currents near the sewages outlets were studied using autonomic buoys and mathematical modeling. Based on historical data and results of recent cruises in 2016–2017 the nutrient concentration, and total petroleum hydrocarbons and organic matter by biological oxygen demand BOD5 content were described. The nutrients content for all studied forms was much lower then Maximum Allowed Concentration and no significant difference between different parts of Crimea coastal waters were marked. Marine waters pollution by TPHs is much higher in Sevastopol region and in Kerch Strait in comparison with Yalta port.

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Luiz, Thiago Boeno Patricio, e José Luiz Silvério da Silva. "CARACTERIZAÇÃO DE PROCESSOS HIDROGEOQUÍMICOS EM ÁGUAS SUBTERRÂNEAS DO SISTEMA AQUÍFERO SANTA MARIA, NA REGIÃO CENTRAL DO RIO GRANDE DO SUL". Ciência e Natura 39, n. 2 (23 maggio 2017): 308. http://dx.doi.org/10.5902/2179460x25911.

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A study was carried out of the hydrogeochemical processes involving the groundwater of the western portion of the Santa Maria Aquifer System (SMAS) in the central region of Rio Grande do Sul. The objective of this study was to characterize the behavior of a portion of the groundwater between São Pedro do Sul, Santa Maria and Restinga Seca municipalities, based on a model between water/rock interaction. Mineralogical and hydrochemical information were analyzed, aiming to model the hydrogeochemical evolution of the aquifer in these municipalities. For this purpose, a processing of the information in a geochemical modeling code was performed, using as previous reference mineralogical studies. The results pointed out the main geochemical interactions responsible for groundwater chemistry, which is strongly dependent of the chemical composition of the recharge waters and the mineralogical contribution of the sedimentary rocks of this aquifer system. The groundwater saturation states showed subsaturation processes tending to the balance of carbonate minerals, indicating the dissolution of these minerals, mainly calcite, as well as supersaturation of clay-minerals ilite, montmorillonite (smectite) and kaolinite, in both cases tending to the alkalinization of the environment. The characterization of the hydrogeochemical properties of aquifers is important for a correct understanding of the processes that occur in it and dominate the regional hydrogeology.

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Güler, Cüneyt, Geoffrey D. Thyne, Hidayet Tağa e Ümit Yıldırım. "Processes Governing Alkaline Groundwater Chemistry within a Fractured Rock (Ophiolitic Mélange) Aquifer Underlying a Seasonally Inhabited Headwater Area in the Aladağlar Range (Adana, Turkey)". Geofluids 2017 (2017): 1–21. http://dx.doi.org/10.1155/2017/3153924.

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The aim of this study was to investigate natural and anthropogenic processes governing the chemical composition of alkaline groundwater within a fractured rock (ophiolitic mélange) aquifer underlying a seasonally inhabited headwater area in the Aladağlar Range (Adana, Turkey). In this aquifer, spatiotemporal patterns of groundwater flow and chemistry were investigated during dry (October 2011) and wet (May 2012) seasons utilizing 25 shallow hand-dug wells. In addition, representative samples of snow, rock, and soil were collected and analyzed to constrain the PHREEQC inverse geochemical models used for simulating water-rock interaction (WRI) processes. Hydrochemistry of the aquifer shows a strong interseasonal variability where Mg–HCO3 and Mg–Ca–HCO3 water types are prevalent, reflecting the influence of ophiolitic and carbonate rocks on local groundwater chemistry. R-mode factor analysis of hydrochemical data hints at geochemical processes taking place in the groundwater system, that is, WRI involving Ca- and Si-bearing phases; WRI involving amorphous oxyhydroxides and clay minerals; WRI involving Mg-bearing phases; and atmospheric/anthropogenic inputs. Results from the PHREEQC modeling suggested that hydrogeochemical evolution is governed by weathering of primary minerals (calcite, chrysotile, forsterite, and chromite), precipitation of secondary minerals (dolomite, quartz, clinochlore, and Fe/Cr oxides), atmospheric/anthropogenic inputs (halite), and seasonal dilution from recharge.

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