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Artykuły w czasopismach na temat "Estuaire inverse"
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Descroix, Luc, Yancouba Sané, Mamadou Thior, Sylvie-Paméla Manga, Boubacar Demba Ba, Joseph Mingou, Victor Mendy i in. "Inverse Estuaries in West Africa: Evidence of the Rainfall Recovery?" Water 12, nr 3 (28.02.2020): 647. http://dx.doi.org/10.3390/w12030647.
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In West Africa, as in many other estuaries, enormous volumes of marine water are entering the continent. Fresh water discharge is very low, and it is commonly strongly linked to rainfall level. Some of these estuaries are inverse estuaries. During the Great Sahelian Drought (1968–1993), their hyperhaline feature was exacerbated. This paper aims to describe the evolution of the two main West African inverse estuaries, those of the Saloum River and the Casamance River, since the end of the drought. Water salinity measurements were carried out over three to five years according to the sites in order to document this evolution and to compare data with the historical ones collected during the long dry period at the end of 20th century. The results show that in both estuaries, the mean water salinity values have markedly decreased since the end of the drought. However, the Saloum estuary remains a totally inverse estuary, while for the Casamance River, the estuarine turbidity maximum (ETM) is the location of the salinity maximum, and it moves according to the seasons from a location 1–10 km downwards from the upstream estuary entry, during the dry season, to a location 40–70 km downwards from this point, during the rainy season. These observations fit with the functioning of the mangrove, the West African mangrove being among the few in the world that are markedly increasing since the beginning of the 1990s and the end of the dry period, as mangrove growth is favored by the relative salinity reduction. Finally, one of the inverse estuary behavior factors is the low fresh water incoming from the continent. The small area of the Casamance and Saloum basins (20,150 and 26,500 km² respectively) is to be compared with the basins of their two main neighbor basins, the Gambia River and the Senegal River, which provide significant fresh water discharge to their estuary.
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Shaha, Dinesh Chandra, Yang-Ki Cho, Bong Guk Kim, M. Rafi Afruz Sony, Sampa Rani Kundu i M. Faruqul Islam. "Spatiotemporal variation of Van der Burgh's coefficient in a salt plug estuary". Hydrology and Earth System Sciences 21, nr 9 (13.09.2017): 4563–72. http://dx.doi.org/10.5194/hess-21-4563-2017.
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Abstract. Salt water intrusion in estuaries is expected to become a serious global issue due to climate change. Van der Burgh's coefficient, K, is a good proxy for describing the relative contribution of tide-driven and gravitational (discharge-driven and density-driven) components of salt transport in estuaries. However, debate continues over the use of the K value for an estuary where K should be a constant, spatially varying, or time-independent factor for different river discharge conditions. In this study, we determined K during spring and neap tides in the dry (< 30 m−3 s−1) and wet (> 750 m−3 s−1) seasons in a salt plug estuary with an exponentially varying width and depth, to examine the relative contributions of tidal versus density-driven salt transport mechanisms. High-resolution salinity data were used to determine K. Discharge-driven gravitational circulation (K ∼ 0.8) was entirely dominant over tidal dispersion during spring and neap tides in the wet season, to the extent that salt transport upstream was effectively reduced, resulting in the estuary remaining in a relatively fresh state. In contrast, K increased gradually seaward (K ∼ 0.74) and landward (K ∼ 0.74) from the salt plug area (K ∼ 0.65) during the dry season, similar to an inverse and positive estuary, respectively. As a result, density-driven inverse gravitational circulation between the salt plug and the sea facilitates inverse estuarine circulation. On the other hand, positive estuarine circulation between the salt plug and the river arose due to density-driven positive gravitational circulation during the dry season, causing the upstream intrusion of high-salinity bottom water. Our results explicitly show that K varies spatially and depends on the river discharge. This result provides a better understanding of the distribution of hydrographic properties.
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Lorenz, Marvin, Knut Klingbeil i Hans Burchard. "Impact of Evaporation and Precipitation on Estuarine Mixing". Journal of Physical Oceanography 51, nr 4 (kwiecień 2021): 1319–33. http://dx.doi.org/10.1175/jpo-d-20-0158.1.
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AbstractRecent studies could link the quantities of estuarine exchange flows to the volume-integrated mixing inside an estuary, where mixing is defined as the destruction of salinity variance. The existing mixing relations quantify mixing inside an estuary by the net boundary fluxes of volume, salinity, and salinity variance, which are quantified as Knudsen or total exchange flow bulk values. So far, river runoff is the only freshwater flux included, and the freshwater exchange due to precipitation and evaporation is neglected. Yet, the latter is the driving force of inverse estuaries, which could not be described by the existing relations. To close this gap, this study considers evaporation and precipitation to complete the existing mixing relations by including cross-surface salinity variance transport. This allows decomposing the mixing into a riverine and a surface transport contribution. The improved relations are tested against idealized two-dimensional numerical simulations of different combinations of freshwater forcing. The mixing diagnosed from the model results agrees exactly with the derived mixing relation. An annual hindcast simulation of the Persian Gulf is then used to test the mixing relations, both exact and approximated, e.g., long-term averaged, for a realistic inverse estuary. The results show that the annual mean mixing contributions of river discharge and evaporation are almost equal, although the freshwater transport due to evaporation is about one order of magnitude larger than the river runoff.
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BITTENCOURT, ABÍLIO C. S. P., GUILHERME C. LESSA, JOSÉ M. L. DOMINGUEZ, LOUIS MARTIN, GERALDO S. VILAS BÔAS i FÉLIX F. FARIAS. "High and low frequency erosive and constructive cycles in estuarine beaches: an example from Garcez Point, Bahia/Brazil". Anais da Academia Brasileira de Ciências 73, nr 4 (grudzień 2001): 599–610. http://dx.doi.org/10.1590/s0001-37652001000400013.
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Monitoring of the morphodynamic variations of the beaches associated with an estuary contiguous with Garcez Point, Bahia, Brazil, and the superposition of aerial photographs from the region, show the presence of distinctive erosive and constructive cycles of low and high frequencies. Between 1959 and 1989, one event of shoreline erosion and progradation was recognized on the oceanic beaches just outside the estuary. Inside the estuary, an erosion phase at the southern margin coincides with a constructive phase at the other side, and vice-versa. On the southern estuarine beach, low-frequency cycles of erosion and progradation are also perceived, but with the inverse trend when compared to the contiguous oceanic beach. During the beach monitoring period (February/1991 to July/1992), the oceanic beach showed retreat rates varying from 23.7m/year, at the channel entrance, to 1.0m/year, three kilometers away from it. During the same period, the estuarine beach advanced at a rate of 60.3m/year. The long-term dynamics of the shoreline position in both sides of the estuarine entrance appears to be related to the position of the channel in the ebb-tidal delta.
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Panfili, Jacques, Jean-Dominique Durand, Khady Diop, Béatrice Gourène i Monique Simier. "Fluctuating asymmetry in fish otoliths and heterozygosity in stressful estuarine environments (West Africa)". Marine and Freshwater Research 56, nr 5 (2005): 505. http://dx.doi.org/10.1071/mf04138.
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Fluctuating asymmetry (FA) is assumed to reflect the developmental instability caused by environmental or genetic stress. Fish otoliths represent a very good tool for investigating the consequence of different effects on FA. Otolith FA analysis, coupled with genetic analysis, has been undertaken on two common West African estuarine species, Ethmalosa fimbriata (EFI) and Sarotherodon melanotheron (SME), in two neighbouring estuaries, in order to highlight the impact of salinity on developmental stability. The Gambia estuary has a normal functioning and the Saloum estuary is inverse (saltier waters in the upper river), reaching extremely high salinities (>100 psu) and constituting severe environmental stress. Five sub-populations of EFI and six of SME were studied along a salinity gradient. The differences between right and left otoliths were estimated with image processing by measuring five dimensions (area, perimeter, diameter, rostrum and posterior radii). Analyses of genetic differentiation at three EPIC and one anonymous nuclear gene loci for EFI and six polymorphic enzymatic loci for SME were carried out to measure the level of heterozygosity. Absolute FA in all otolith traits examined was unaffected by gender but increased significantly with fish size. Size-corrected absolute FA did not show any significant difference among sites differing largely in salinity, although a higher asymmetry in otolith area was recorded in the saltiest site. These findings suggest that otolith asymmetry is a poor indicator of osmotic stress. The individual heterozygosity level did not seem to have an effect on otolith FA for either species, even though a slight correlation appeared with otolith area or perimeter. Otolith FA cannot be considered to be a useful indicator for estimating changes linked with environmental or genetic stress in these estuaries.
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Hofmann, A. F., F. J. R. Meysman, K. Soetaert i J. J. Middelburg. "Factors governing the pH in a heterotrophic, turbid, tidal estuary". Biogeosciences Discussions 6, nr 1 (7.01.2009): 197–240. http://dx.doi.org/10.5194/bgd-6-197-2009.
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Abstract. A method to quantify the influence of kinetically modelled biogeochemical processes on the pH of an ecosystem with time variable acid-base dissociation constants is presented and applied to the heterotrophic, turbid Scheldt estuary (SW Netherlands, N Belgium). Nitrification is identified as the main process governing the pH profile of this estuary, while CO2 degassing and advective-dispersive transport "buffer" the effect of nitrification. CO2 degassing accounts for the largest proton turnover per year in the whole estuary. There is a clear inverse correlation between oxygen turnover and proton turnover. The main driver of long-term changes in the mean estuarine pH from 2001 to 2004 is a changing freshwater flow which influences the pH "directly" via [∑CO2] and [TA] and to a significant amount also "indirectly" via [∑NH4+] and the nitrification rates in the estuary.
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Medeiros, AMA, JEL Barbosa, PR Medeiros, RM Rocha i LF Silva. "Salinity and freshwater discharge determine rotifer distribution at the Mossoró River Estuary (Semiarid Region of Brazil)". Brazilian Journal of Biology 70, nr 3 (sierpień 2010): 551–57. http://dx.doi.org/10.1590/s1519-69842010000300011.
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The present study aimed at evaluating differences in rotifer distribution in three estuarine zones in an inverse estuary located in the Semiarid Region of Brazil. Zones were chosen based on their proximity to the ocean and river border as a means of reflecting a horizontal salinity gradient. High freshwater discharge during the rainy season was the major determinant of rotifer composition. On the other hand, due to higher salinity values during the dry season, very low values of species richness and abundance were observed in all zones. Therefore, the study highlights the constraints of salinity and the positive influence of seasonality and river proximity on rotifer species in a semiarid estuarine environment.
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Cai, Huayang, Ping Zhang, Erwan Garel, Pascal Matte, Shuai Hu, Feng Liu i Qingshu Yang. "A novel approach for the assessment of morphological evolution based on observed water levels in tide-dominated estuaries". Hydrology and Earth System Sciences 24, nr 4 (16.04.2020): 1871–89. http://dx.doi.org/10.5194/hess-24-1871-2020.
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Abstract. Assessing the impacts of both natural (e.g. tidal forcing from the ocean) and human-induced changes (e.g. dredging for navigation and land reclamation) on estuarine morphology is particularly important for the protection and management of the estuarine environment. In this study, a novel analytical approach is proposed for the assessment of estuarine morphological evolution in terms of tidally averaged depth on the basis of the observed water levels along the estuary. The key lies in deriving a relationship between wave celerity and tidal damping or amplification. For given observed water levels at two gauging stations, it is possible to have a first estimation of both wave celerity (distance divided by tidal travelling time) and tidal damping or amplification rate (tidal range difference divided by distance), which can then be used to predict the morphological changes via an inverse analytical model for tidal hydrodynamics. The proposed method is applied to the Lingdingyang Bay of the Pearl River Estuary, located on the southern coast of China, to analyse the historical development of the tidal hydrodynamics and morphological evolution. The analytical results show surprisingly good correspondence with observed water depth and volume in this system. The merit of the proposed method is that it provides a simple approach for understanding the decadal evolution of the estuarine morphology through the use of observed water levels, which are usually available and can be easily measured.
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Burchard, Hans. "Combined Effects of Wind, Tide, and Horizontal Density Gradients on Stratification in Estuaries and Coastal Seas". Journal of Physical Oceanography 39, nr 9 (1.09.2009): 2117–36. http://dx.doi.org/10.1175/2009jpo4142.1.
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Abstract The aim of this one-dimensional water column study is to combine modified versions of three characteristic parameters for periodic tidal flow under the influence of a longitudinal buoyancy gradient—the horizontal Richardson number, the inverse Strouhal number, and the inverse Ekman number—into a parameter space study, including constant wind forcing from various directions. It is shown how the underlying dynamical equations can be cast into nondimensional form, depending mainly on these three nondimensional parameters plus the relative wind speed and the wind direction. Idealized model simulations are carried out for the whole realistic range of horizontal Richardson and inverse Strouhal numbers for various latitudes, showing the amplitude of the tidally induced stratification for a wide range of scenarios. It is found that classical threshold values for the horizontal Richardson number, indicating the switch from periodic stratification to permanent stratification, are valid only for special cases, and that this switch also strongly depends on the inverse Strouhal number, the inverse Ekman number, and the wind vector. The transverse residual flow is close to the thermal wind balance for a variety of parameters, and nondimensionalized longitudinal residual flow shows the classical estuarine exchange flow pattern with little variation in the near-bed onshore component. Wind straining is confirmed as an important estuarine and coastal process, enhancing estuarine circulation for offshore (down estuary) winds and vice versa. Agreement with field data from Liverpool Bay is good, including the explanation of a flood tide local maximum of the dissipation rate in the upper half of the water column. An equation for the second time derivative of the potential energy anomaly is derived for quantifying the dynamical processes leading to stratification due to the straining of the horizontal density gradient.
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Abdul Aziz, Nandi, Yonvitner, Sigid Hariyadi, Syamsul Bahri Agus i I. Wayan Nurjaya. "Sedimentation Profile in Coastal Water Jakarta Bay". Journal of Tropical Fisheries Management 6, nr 1 (12.01.2023): 35–44. http://dx.doi.org/10.29244/jppt.v6i1.43452.
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The waters of Jakarta Bay are one of the waters that are influenced by several fresh water flows that enter from the DKI Jakarta area and its surroundings. Sediment that enters the waters of Jakarta Bay is produced by the activities of the people who live in the Jakarta area and its surroundings. This study aims to analyze the sedimentation and distribution of suspended solids in the Jakarta Bay estuary using an observational approach and spatial analysis. This study uses the Inverse Distance Weighting (IDW) interpolation method. The dominant distribution of sediment in Jakarta Bay is sand with a size ranging from 0.25 to 0.125 mm. TSS (Total Suspended Solids) levels in 11 estuaries in Jakarta Bay ranged from 21 to 150 mg/L in first period and 11 ˗ 259 mg/L in second period. Sedimentation rates that occurred in 11 Jakarta Bay estuaries ranged from 11.12 g/cm2/day to 619.5 g/cm2/day in period one and 10.96 g/cm2/day to 1232.06 g/cm2/day in the second period which is located in Muara Cilincing in both periods. There is a suitable relationship between the TSS value and the sedimentation rate. Estuary TSS values and sedimentation rates are influenced by seasons and anthropogenic activities that occur in the estuary such as reclamation.
Rozprawy doktorskie na temat "Estuaire inverse"
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Sané, Babacar. "Ecophysiologie de l'arche (Senilia senilis), approche expérimentale pour une meilleure compréhension de ses traits d'histoires de vie dans l'estuaire inverse du Sine-Saloum". Electronic Thesis or Diss., Brest, 2024. http://theses-scd.univ-brest.fr/2024/These-2024-SML-Biologie_marine-SANE_Babacar.pdf.
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Dans l’estuaire inverse du Sine-Saloum (Sénégal), l’arche (Senilia senilis) est une espèce de bivalve clé pour les communautés de femmes qui les exploitent depuis des millénaires. Or, le manque d’informations sur sa biologie ne nous permet pas de prédire la réponse de l’espèce aux variations de ses conditions de vie, en particulier dans un contexte de changement global. Pour répondre à cette problématique, trois questions de recherche ont été posées : (1) Quelles sont ses limites de tolérance physiologique à la température et à la salinité ? (2) Quelles sont les variations saisonnières de sa croissance et la phénologie de sa reproduction dans les principaux sites de pêche artisanale du Sine-Saloum ? (3) Comment la saisonnalité du gradient de salinité à l’échelle du delta influence-t-elle son écologie trophique et sa croissance ? Pour répondre à ces questions, une approche intégrative a été mise en œuvre, combinant des expérimentations en laboratoire, in-situ et des protocoles d’échantillonnage saisonnier. Les résultats de cette étude permettent de décrire l’effet majeur des gradients de salinité, pilotés par la mousson, dans la régulation des traits d’histoire de vie des arches du Sine-Saloum. Bien que l’on démontre que l’espèce supporte une large gamme de variations de salinité, comprise entre 12 à 60, et des températures élevées (seuil à 39°C), ses performances de croissance et la phénologie de sa reproduction suivent un schéma saisonnier et une hétérogénéité spatiale étroitement liés aux variations de salinité. Son écologie trophique apparaît également fortement structurée par le cycle saisonnier de mousson, avec des sources de nourriture variant conjointement en fonction de la saison et de la distance à l’embouchure. Ces résultats contribuent à faire progresser notre connaissance de la niche écologique de l’espèce. Ils constituent à ce titre des jalons indispensables pour contribuer à l'élaboration d'approches de modélisation, de l'échelle individuelle à l'échelle de la population. Ce sont des éléments fondamentaux pour soutenir la durabilité de l’activité de pêche artisanaleIn the inverse estuary of the Sine-Saloum (Senegal), the bloody cockle (Senilia senilis) is a key bivalve species for the communities of women who have exploited it for thousands of years. Yet very little information is available about its biology. It is therefore impossible to predict the species'response to variations in its living conditions, particularly in the context of global change. To address this issue, three research questions were posed: (1) What are its physiological tolerance limits to temperature and salinity? (2) What are the seasonal variations in its growth and the phenology of its reproduction in the main artisanal fishing sites in the Sine-Saloum ? (3) How does the seasonality of the salinity gradient at estuary scale influence its trophic ecology and growth? To answer these questions, an integrative approach was implemented, combining laboratory and in situ experiments and seasonal sampling protocols Our results highlight the major effect of salinity gradients, driven by the monsoon, in regulating the life-history traits of S. senilis in the Sine-Saloum. Although the species has been shown to tolerate a wide range of salinity variations, from 12 to 60, and high temperatures (threshold at 39°C), its growth performance and reproductive phenology follow a seasonal pattern and spatial heterogeneity closely linked to salinity variations. Its trophic ecology also appears to be strongly structured by the seasonal monsoon cycle, with food sources varying according to season and distance from the estuary’mouth. These results help to advance our knowledge of the species' ecological niche. As such, they are essential milestones for contributing to the development of modelling approaches, from the individual to the population scale. These are fundamental elements in supporting the sustainability of small-scale fishing
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Gning, Cisse Ndombour. "Écologie trophique des juvéniles de quatre espèces de poissons dans l'estuaire inverse du Sine-Saloum (Sénégal) : influence des conditions de salinité contrastées". Montpellier 2, 2008. http://www.theses.fr/2008MON20151.
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L'estuaire inverse du Sine-Saloum (Sénégal) caractérisé par une situation de salinité aval-amont contrastée héberge de fortes populations de jeunes poissons. L'écologie trophique des juvéniles des espèces suivantes : Eucinostomus melanopterus, Ethmalosa fimbriata, Monodactylus sebae et Sarotherodon melanotheron, a été abordée par deux approches simultanées : la méthode d'analyse des contenus stomacaux et celle d'analyse des isotopes stables. La première approche a révélé que les jeunes poissons exploitent une grande communauté d'invertébrés dont la plupart est inféodé aux zones de mangroves et en constitue généralement une faune typique connue sous le nom de périphyton. Des changements du type de ressources alimentaires exploitées par les juvéniles de poissons ont été identifiés avec la taille des individus chez toutes les espèces étudiées, ainsi que des variations spatiales importantes. L'analyse des isotopes stables a montré que le réseau trophique aboutissant aux jeunes poissons est affecté par ce contraste et fonctionne différemment entre les deux extrémités de l'estuaire. En aval, où les salinités sont voisines de 40, où la mangrove est présente et le peuplement est dense et diversifié, le réseau trophique est pélagique et avec comme ligne de base le phytoplancton. Aucune contribution de la mangrove n'a été détectée à ce niveau. Tandis qu'en amont, où les salinités sont très élevées (voisines de 100 et plus), le réseau trophique est plutôt benthique et soutenu le microphytobenthos. L'écologie trophique des juvéniles de poissons est affectée par les conditions locales de salinités. La plasticité trophique observée chez les jeunes poissons peut être considéré comme une stratégie d'adaptation parmi d'autres dans le Sine-Saloum, face au stress environnementalThe Sine-Saloum inverse estuary, characterized by contrasting salinity, is an important nursery habitat for juvenile fish. The trophic ecology of juvenile for following species: Eucinostomus melanopterus, Ethmalosa fimbriata, Monodactylus sebae and Sarotherodon melanotheron were investigated by coupling stomach content and stables isotopes (¦Ä13C and ¦Ä15N) analyses. The first method revealed that almost all juveniles preyed on a wide diversity of organisms belonging to the periphytic community of mangrove roots. Food change with length for all juveniles and important spatial variation were also identified. Stables isotopes analyse indicate that the food webs origins reaching juvenile fish change with local condition salinity. At downstream, with the moderate salinity (40), the food web is based on phytoplankton without any contribution of mangrove carbon. While in upstream, with high salinity, the food web is based on microphytobenthos. Conditions salinities have effects on juvenile fishes ecology trophic. The plasticity trophic detected may be an particularity adaptation to environmental stress
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Riche, Olivier. "Time-dependent inverse box-model for the estuarine circulation and primary productivity in the Strait of Georgia". Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37738.
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During 2002–2006, a comprehensive set of observations covering physical, biological, radiative and atmospheric parameters was obtained from the southern Strait of Georgia (SoG), Western Canada by the STRATOGEM program. Monthly time series of estuarine layer transports over 2002–2005 were estimated using a time-dependent 2-box model in a formal inverse approach. These transports are then consistent with the temperature and salinity fields, as well as riverine freshwater inflow (R) and atmospheric heat fluxes. Uncertainty was analyzed by resampling observations using bootstrap methods. The transport time series were then combined with observations of nutrient concentrations to construct monthly time series of nutrient uptake for nitrate, phosphate, and silicic acid.
Analysis of these time series suggests that the SoG estuarine circulation is not very sensitive to the seasonal changes of R. Comparison of the surface layer transport (U₁) and R yields the first observational relationship between the SoG estuarine circulation and R. This relationship (U₁=2.68 m²s⁻²/³× 10³ R¹/³) is consistent with estuarine theories. Although the flows change slightly with the freshet, a 5-fold change in R results only in a 40% change in U₁. Based on the calculated sink of near-surface nutrients, net primary productivity is estimated to be 212 gC m⁻²yr⁻¹, which is similar to values obtained differently in similar estuaries. Comparison of the nitrate and phosphate uptake rates suggests that the primary productivity (PP) is mainly new PP during spring and summer. Thus, PP is mainly controlled by the upwelling supply of nutrients through deep inflow and entrainment. The uptake of silicic acid (Si) is almost two times larger than the uptake of nitrate during diatom spring blooms, while it is similar during the summer blooms. Such a high Si uptake suggests that spring diatoms form heavier frustules or that heterotrophic silicoflagellates compete with diatoms for Si. Speculative considerations based on comparison of the estimated production rate of near-surface oxygen and new PP also suggest that the regenerated PP is small. In addition, the summer heterotrophic respiration might be in excess by as much as
2 gO m⁻² d⁻¹ relative to the net PP.
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Lima, Edgar Barbosa. "Problemas inversos aplicados à identificação de parâmetros hidrodinâmicos de um modelo do estuário do rio Macaé". Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3913.
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Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de JaneiroEsta tese tem por objetivo propor uma estratégia de obtenção automática de parâmetros hidrodinâmicos e de transporte através da solução de problemas inversos. A obtenção dos parâmetros de um modelo físico representa um dos principais problemas em sua calibração, e isso se deve em grande parte à dificuldade na medição em campo desses parâmetros. Em particular na modelagem de rios e estuários, a altura da rugosidade e o coeficiente de difusão turbulenta representam dois dos parâmetros com maior dificuldade de medição. Nesta tese é apresentada uma técnica automatizada de estimação desses parâmetros através deum problema inverso aplicado a um modelo do estuário do rio Macaé, localizado no norte do Rio de Janeiro. Para este estudo foi utilizada a plataforma MOHID, desenvolvida na Universidade Técnica de Lisboa, e que tem tido ampla aplicação na simulação de corpos hídricos. Foi realizada uma análise de sensibilidade das respostas do modelo com relação aos parâmetros de interesse. Verificou-se que a salinidade é uma variável sensível a ambos parâmetros. O problema inverso foi então resolvido utilizando vários métodos de otimização através do acoplamento da plataforma MOHID a códigos de otimização implementados em Fortran. O acoplamento foi realizado de forma a não alterar o código fonte do MOHID, possibilitando a utilização da ferramenta computacional aqui desenvolvida em qualquer versão dessa plataforma, bem como a sua alteração para o uso com outros simuladores. Os testes realizados confirmam a eficiência da técnica e apontam as melhores abordagens para uma rápida e precisa estimação dos parâmetros.
This thesis presents a strategy for automatically obtaining hydrodynamic and transport parameters by means of the solution of inverse problems. Obtaining the parameters of a physical model represents a major problem in its calibration, and this is largely due to the difficulty associated to the field measurements of these parameters. In particular by modeling rivers and estuaries, the roughness height and the turbulent diffusion coefficient represent two of the most difficult parameters to measure or estimate. Here, an automated technique for estimation of these parameters through an inverse problem is applied to a model of the Macaé estuary, located in northern Rio de Janeiro. For this investigation, hydrodynamic and transport models were built in the MOHID platform, developed in the Technical University of Lisbon, which has had wide application in simulation of water bodies. A sensitivity analysis was performed regarding the model responses with respect to the parameters of interest. It was verified that salinity is a sensitive variable for both parameters. The inverse problem was then solved using various optimization methods by coupling the MOHID platform to optimization codes implemented in Fortran. The coupling was carried in a way to not change the MOHID source code, allowing the use of the computational tool here developed in any version of this platform, as well as its modification for use with other simulators. The tests confirm the efficiency of the technique and suggest the best approaches for a fast and accurate estimation of the parameters.
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Sloterdijk, Hans [Verfasser], Werner [Akademischer Betreuer] Ekau, Ulrich [Gutachter] Saint-Paul i Werner [Gutachter] Ekau. "Environmental and Physical Factors Affecting the Diversity and Distribution of the Ichthyoplankton in an "Inverse Estuary" , the Sine Saloum (Senegal) / Hans Sloterdijk ; Gutachter: Ulrich Saint-Paul, Werner Ekau ; Betreuer: Werner Ekau". Bremen : Staats- und Universitätsbibliothek Bremen, 2018. http://d-nb.info/1170321011/34.
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Harbison, John Edwin. "Groundwater chemistry and hydrological processes within a Quaternary coastal plain: Pimpama, Southeast Queensland". Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16647/1/John%20Harbison%20Thesis.pdf.
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The Pimpama estuarine plain in subtropical southeast Queensland is comprised of Quaternary sediments infilling older bedrock. These multilayered unconsolidated sediments have various depositional origins, and are highly heterogeneous. The plain is low-lying and the surface drainage is controlled by flood mitigation measures including tidal gates and channelised streams. The control of surface drainage potentially affects the shallow water table. This modification of hydrology has implications for future viability of agriculture and also the environmental health of waterways. Increased landscape modification and water management is likely in the coming years. The combination of sediment heterogeneity, low hydraulic gradients, and artificial drainage modification result in the plain being hydrogeologically complex. In order to understand hydrologic processes in this setting, a multi-disciplinary research programme was conducted which included a drilling program, overland electromagnetic induction and other geophysical surveys (downhole gamma log, electromagnetic induction and magnetic susceptibility) to initially establish the geologic framework. These surveys were followed by hydrogeochemical testing which includes for major and minor ions and also stable isotopes, and mineralogical analysis of drillhole material. Underlying basement rock occurs at up to 60 m depth. Unconsolidated gravel and sand deposits occur within incised paleo-valleys and are overlain by predominantly low-permeability fluvial sandy clays and estuarine and lagoonal muds. Fine-grained delta sands occur in the top 15 m of the sub-surface. Within the unconsolidated sediments, hydrodynamic trends clearly discriminated between upper unconfined and lower semi-confined aquifer systems. A comparison of surface water and shallow groundwater levels indicate limited interaction of groundwater and surface water. Hydrogeochemical analysis effectively distinguished between groundwater bodies, and also distinguished saline groundwater from seawater. Trends in major ion chemistry in the semi-confined system (particularly Na/Cl and Ca/Cl ratios) showed ion exchange accompanying saline intrusion. However, due to factors such as mineral dissolution, major ion chemistry does not clearly identify solute flux trends in the shallow aquifer system. Water stable isotope analysis (δ18O and δ2H) indicated the provenance of fresh and saline groundwater and also the relative importance of the principal hydrologic processes, i.e. evaporation and water uptake by plants. Groundwater exhibited a wide range in salinity, from very fresh to hypersaline. The formation of hypersaline groundwater was attributed largely to uptake of water by mangrove forests. Since mangrove forests were more extensive at the time of the Holocene maximum sea level (approximately 6,000 years ago) than at present, some of this groundwater may represent relict salinity from this earlier time. The relationship of relict salinity to low permeability sediments, particularly at intermediate depths, and their depositional history was examined. Vertical salinity gradients and hydrogeochemistry within these sediments varied according to position within the plain, suggesting deposition under various hydrological and sea level regimes. A preliminary investigation using analysis of stable sulfate isotopes (δ34S and δ18OSO4) was made. This study shows substantial potential for the application of this technique for quantification of solute flux and sulfur chemical transformations within settings such as this coastal plain. To establish shallow groundwater flow processes, a MODFLOW-based numerical model was used to inversely estimate aquifer parameters under various recharge scenarios. The model was designed to examine the relative importance of evapotranspiration and discharge to surface waters. However, largely due to the complexity of the drainage network and non-uniform surface water flows, the quantification of surface water- groundwater interaction by consideration of hydrodynamics is problematic. Therefore, the chemistry of groundwater and surface water was compared. While the estimated contribution of rainfall to groundwater level fluctuations was significant (46%), high evapotranspiration rates reduced net recharge and it was concluded that baseflow to drains and creeks during dry periods was insignificant, and groundwater velocities in the shallow aquifer are low. The study illustrates the value of both hydrodynamic and hydrogeochemical analyses in estuarine settings where relict salinity and groundwater-aquifer interactions impact significantly on water quality. Saline groundwater is chemically distinct from theoretical mixtures of seawater and freshwater. The study also demonstrates the value of particular chemical parameters, e.g. Na/Cl and SO4/Cl ratios and stable water isotopes, for identifying hydrologic processes in this setting.
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Harbison, John Edwin. "Groundwater chemistry and hydrological processes within a Quaternary coastal plain: Pimpama, Southeast Queensland". Queensland University of Technology, 2007. http://eprints.qut.edu.au/16647/.
Pełny tekst źródłaStreszczenie:
The Pimpama estuarine plain in subtropical southeast Queensland is comprised of Quaternary sediments infilling older bedrock. These multilayered unconsolidated sediments have various depositional origins, and are highly heterogeneous. The plain is low-lying and the surface drainage is controlled by flood mitigation measures including tidal gates and channelised streams. The control of surface drainage potentially affects the shallow water table. This modification of hydrology has implications for future viability of agriculture and also the environmental health of waterways. Increased landscape modification and water management is likely in the coming years. The combination of sediment heterogeneity, low hydraulic gradients, and artificial drainage modification result in the plain being hydrogeologically complex. In order to understand hydrologic processes in this setting, a multi-disciplinary research programme was conducted which included a drilling program, overland electromagnetic induction and other geophysical surveys (downhole gamma log, electromagnetic induction and magnetic susceptibility) to initially establish the geologic framework. These surveys were followed by hydrogeochemical testing which includes for major and minor ions and also stable isotopes, and mineralogical analysis of drillhole material. Underlying basement rock occurs at up to 60 m depth. Unconsolidated gravel and sand deposits occur within incised paleo-valleys and are overlain by predominantly low-permeability fluvial sandy clays and estuarine and lagoonal muds. Fine-grained delta sands occur in the top 15 m of the sub-surface. Within the unconsolidated sediments, hydrodynamic trends clearly discriminated between upper unconfined and lower semi-confined aquifer systems. A comparison of surface water and shallow groundwater levels indicate limited interaction of groundwater and surface water. Hydrogeochemical analysis effectively distinguished between groundwater bodies, and also distinguished saline groundwater from seawater. Trends in major ion chemistry in the semi-confined system (particularly Na/Cl and Ca/Cl ratios) showed ion exchange accompanying saline intrusion. However, due to factors such as mineral dissolution, major ion chemistry does not clearly identify solute flux trends in the shallow aquifer system. Water stable isotope analysis (δ18O and δ2H) indicated the provenance of fresh and saline groundwater and also the relative importance of the principal hydrologic processes, i.e. evaporation and water uptake by plants. Groundwater exhibited a wide range in salinity, from very fresh to hypersaline. The formation of hypersaline groundwater was attributed largely to uptake of water by mangrove forests. Since mangrove forests were more extensive at the time of the Holocene maximum sea level (approximately 6,000 years ago) than at present, some of this groundwater may represent relict salinity from this earlier time. The relationship of relict salinity to low permeability sediments, particularly at intermediate depths, and their depositional history was examined. Vertical salinity gradients and hydrogeochemistry within these sediments varied according to position within the plain, suggesting deposition under various hydrological and sea level regimes. A preliminary investigation using analysis of stable sulfate isotopes (δ34S and δ18OSO4) was made. This study shows substantial potential for the application of this technique for quantification of solute flux and sulfur chemical transformations within settings such as this coastal plain. To establish shallow groundwater flow processes, a MODFLOW-based numerical model was used to inversely estimate aquifer parameters under various recharge scenarios. The model was designed to examine the relative importance of evapotranspiration and discharge to surface waters. However, largely due to the complexity of the drainage network and non-uniform surface water flows, the quantification of surface water- groundwater interaction by consideration of hydrodynamics is problematic. Therefore, the chemistry of groundwater and surface water was compared. While the estimated contribution of rainfall to groundwater level fluctuations was significant (46%), high evapotranspiration rates reduced net recharge and it was concluded that baseflow to drains and creeks during dry periods was insignificant, and groundwater velocities in the shallow aquifer are low. The study illustrates the value of both hydrodynamic and hydrogeochemical analyses in estuarine settings where relict salinity and groundwater-aquifer interactions impact significantly on water quality. Saline groundwater is chemically distinct from theoretical mixtures of seawater and freshwater. The study also demonstrates the value of particular chemical parameters, e.g. Na/Cl and SO4/Cl ratios and stable water isotopes, for identifying hydrologic processes in this setting.
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Rodrigues, David Manuel Monteiro. "Movimentos e distribuição do pilrito-de-peito-preto Calidris alpina nas zonas intertidais no estuário do Tejo (Portugal)". Master's thesis, Universidade de Évora, 2012. http://hdl.handle.net/10174/15691.
Pełny tekst źródłaStreszczenie:
O pilrito-de-peito-preto Calidris alpina é uma das espécies de aves limícolas mais abundantes do estuário do Tejo (Portugal). Para determinar se existem diferenças na utilização das zonas intertidais consoante o refúgio utilizado, os movimentos de 12 pilritos-de-peito-preto, capturados em dois dos locais de refúgio mais importantes do estuário do Tejo, foram monitorizados durante os períodos de inverno e da migração. A quase totalidade das localizações foi obtida numa área até 5 km de distância em redor do refúgio utilizado, no entanto, as aves alimentaram-se a diferentes classes de distância consoante o refúgio seleccionado. As dimensões das áreas vitais e dos centros de actividade não apresentaram diferenças significativas, sendo semelhantes quer entre períodos quer entre indivíduos de diferentes refúgios. Este estudo sugere que os refúgios seleccionados pelos pilritos-de-peito-preto têm grandes implicações na forma como e até onde estas aves se distribuem enquanto se alimentam; ABSTRACT:The dunlin Calidris alpina it is one of the most abundant species of waders in the Tagus estuary (Portugal). To determinate if the intertidal flats are used differently according to the roost used, the movement of twelve dunlins captured in two of the most important estuary roosts were monitored during periods of winter and migration. Almost all the obtained localizations were within 5km around the roost selected; however the birds feed in different classes of distance from the selected roost. The home range dimensions and the core area did not shown significant differences, being similar within periods or between individuals from different roosts. The study suggests that the selection of the roosts made by the dunlin has major implications in the way and where these birds are distributed during feeding.
Części książek na temat "Estuaire inverse"
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Vézina, Alain F. "Construction of flow networks using inverse methods". W Coastal and Estuarine Studies, 62–81. Washington, D. C.: American Geophysical Union, 1989. http://dx.doi.org/10.1029/ce032p0062.
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Kämpf, Jochen. "South Australia’s Large Inverse Estuaries: On the Road to Ruin". W Estuaries of the World, 153–66. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-7019-5_9.
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"inverse estuary". W Dictionary Geotechnical Engineering/Wörterbuch GeoTechnik, 746. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-41714-6_91602.
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"PHYSICAL PROCESSES IN INVERSE ESTUARINE SYSTEMS". W Oceanography And Marine Biology, 6–69. CRC Press, 1997. http://dx.doi.org/10.1201/b12590-2.
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Staton, Joseph L., Brian A. Canada, Stephen A. Borgianini i Karen M. Barkel. "Colonization of Coastal and Estuarine Environments". W Evolution and Biogeography, 247–79. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190637842.003.0010.
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Coastal and estuarine environments are some of the best-known and most well-studied ecosystems in the world in that these regions lie in close proximity to much of the world’s human population. The crustaceans that inhabit these environments, both as adults and larvae, are adapted to the high productivity that characterizes such areas. We summarize their adaptations and behaviors and the physical characteristics of coastal zones and estuaries in shallower waters (<200 m). In an attempt to objectively review worldwide diversity and endemism within the Crustacea from coastal and estuarine environments, we have used open access global collection data and developed a novel application of an informatics principle (term frequency-inverse document frequency [TF-IDF]) to identify regions with unique faunal assemblages that typify some coastal, shallow waters to assess potential endemism (as assessed by our technique) across groups at differing taxonomic levels. Crustaceans, as a whole, show highest species richness and endemism in three clusters (using the TF-IDF assessment): the eastern temperate north Atlantic, the western temperate north Atlantic, and the western tropical south Pacific. Peracarid and decapod species dominate the collection data, making up 94% of all species analyzed. Peracarids dominate species richness across all temperate zones, yet their highest predicted coastal endemism appears in the eastern north Atlantic by our index. Our analyses using this new method focused on species from less than 200 m depth worldwide. Upcoming impacts of changing sea levels and increases in global temperature will likely have their greatest impact on the fauna of these zones.
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Provost, C. "The Variational Inverse Method Revisited". W Three-Dimensional Models of Marine and Estuarine Dynamics, 625. Elsevier, 1987. http://dx.doi.org/10.1016/s0422-9894(08)70471-9.
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Niquil, N., B. Saint-Béat, G. A. Johnson, K. Soetaert, D. van Oevelen, C. Bacher i A. F. Vézina. "Inverse Modeling in Modern Ecology and Application to Coastal Ecosystems". W Treatise on Estuarine and Coastal Science, 115–33. Elsevier, 2011. http://dx.doi.org/10.1016/b978-0-12-374711-2.00906-2.
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Martel, F., i C. Provost. "The Branching of the Gulf Stream Revisited using the Variational Inverse Method". W Three-Dimensional Models of Marine and Estuarine Dynamics, 627. Elsevier, 1987. http://dx.doi.org/10.1016/s0422-9894(08)70472-0.
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Bowers, D. G. "Models of Density Current Outflows form Inverse Estuaries: With Application to Spencer Gulf, South Australia". W Modeling Marine Systems, 1–24. CRC Press, 2018. http://dx.doi.org/10.1201/9781351074704-1.
Pełny tekst źródłaStreszczenia konferencji na temat "Estuaire inverse"
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Chen, Jay Chung, i Lai Ah Wong. "Inverse Estimation of Estuary Flux". W Eighth International Conference on Estuarine and Coastal Modeling. Reston, VA: American Society of Civil Engineers, 2004. http://dx.doi.org/10.1061/40734(145)54.
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Shen, Jian, i Albert Y. Kuo. "Eutrophication Model Calibration as a Coupled Inverse Problem". W Seventh International Conference on Estuarine and Coastal Modeling. Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40628(268)37.
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Tong, Chaofeng, Jinhai Zheng, Cheng Zhang i Claude Guilbaud. "Salinity Response to the Runoff From Yangtze River Basin at Qingcaosha Reservoir Area in Yangtze Estuary". W ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-20422.
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Qingcaosha Reservoir locates in the Yangtze Estuary of China is an estuary reservoir. As the third water source region of Shanghai city, about 717,000 m3/d raw water will be supplied from the Reservoir when the project is finished. In order to avoid salt water from saltwater intrusion, it is necessary to reveal the rule of salinity variation in the Qingcaosha Reservoir area. Saltwater intrusion in the Yangtze Estuary is mainly impacted by the fresh water discharge from the Yangtze River and the open sea tides. The salinity response of Qingcaosha Reservoir area to the runoff will be discussed. In the paper, the hydrodynamic and saltwater intrusion model of Yangtze Estuary is developed and calibrated with the TELEMAC model. The model domain covers the whole Yangtze Estuary and the Hangzhou Bay. Hydrological data of 9 tidal stations and 5 current measuring points during spring tide, middle tide and neap tide in March, 2002, are used to calibrate the salinity data. Comparisons of the calculated results and measurements show that the hydrodynamic model and the salinity model can reflect precisely the law of currents and the salt water intrusion in the Yangtze Estuary, and they can be used to forecast the salinity in Qingcaosha Reservoir region. According to the different characteristic discharges corresponding to the different cumulative frequencies, the salinity distributions in Yangtze Estuary are calculated under the conditions of different flow into the sea. The simulation results show that the salinity values will decrease with the increasing of discharge. When the upstream discharge is below 16,700 m3/s, the average value in dry season, the salinity response to the runoff is very sensitive. The salinity amplitude at the downstream gate area is inversely proportional to the upstream discharge, whereas, the parameter at upstream gate area is proportional to the upstream discharge if it isn’t up to the average value in dry seasons. The salinity at the downstream area of reservoir is obviously higher than that at the head region.
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Al-Taliby, Wissam, Ashok Pandit, Antonio Berber i Howell Heck. "The Use of Inverse Distance Weighted Interpolation to Calibrate the Vertical Hydraulic Conductivity below an Estuary". W World Environmental and Water Resources Congress 2017. Reston, VA: American Society of Civil Engineers, 2017. http://dx.doi.org/10.1061/9780784480618.013.
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Sadrinasab, Masoud, i Karim Kenarkoohi. "A Three-Dimensional Numerical Modelling Study of the Sound Velocity Profiles in the Persian Gulf". W ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57062.
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The Persian Gulf connects to the Indian Ocean via the Strait of Hormuz. In this study, a three-dimensional hydrodynamic model (COHERENS) is employed in a fully prognostic mode to derive sound velocity profiles in the Persian Gulf, an evaporation-driven inverse estuary that is governed by import of surface water from the adjacent ocean and export of saline bottom gulf water through the Strait of Hormuz. During spring and summer, a cyclonic overturning circulation establishes along the full length of the Gulf. During autumn and winter, this circulation breaks up into mesoscale eddies, laterally stirring most of the Gulf’s surface waters. Output of the model shows that sound velocity in the Persian Gulf depends mainly on the temperature in the surface layer whereas the bottom layer as well as the southern part of the Gulf depends on temperature and salinity. Maximum sound velocity occurs during summer in the Persian Gulf which decreases gradually moving from Strait of Hormuz to the north western part of the Gulf. A gradual decrease in sound velocity profiles with depth was commonly observed almost at all stations in the Gulf. However, an exception occurred in Strait of Hormuz during winter. The results of the model are very close to previous observations.
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Juarez, Braulio, i Arnoldo Valle-Levinson. "Bloqueo al intercambio de agua en un estuario generado por un pulso de agua salobre proveniente del océano". W I Congreso Internacional de Ciencias Exactas y Naturales. Universidad Nacional, 2019. http://dx.doi.org/10.15359/cicen.1.53.
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La formación de tapones de sal, i.e., bloqueo al intercambio de agua en estuarios, suele estar atribuida a estuarios de flujo reducido cuando su tasa de evaporación excede o es similar a la tasa de aporte de agua dulce. Datos mensuales y anuales en este estudio mostraron un tapón de sal formado por un pulso de agua dulce procedente de la plataforma oceánica hacia la entrada de una bahía somera, bahía de Barataria, localizada en el delta del rio Mississippi. Un mes de datos de corrientes mostró dos patrones predominantes: una circulación verticalmente homogénea y una circulación bidireccional. La circulación bidireccional mostró generalmente una circulación estuarina inversa con flujo entrando en superficie y saliendo por debajo. La circulación negativa ocurrió debido a la formación del tapón de sal observado con datos de salinidad a lo largo de la bahía para el mismo periodo de tiempo. La formación del tapón de sal fue favorecida por vientos soplando hacia la costa. Para explorar la persistencia de dicho tapón observado en un mes, se analizaron además datos de salinidad en 4 sitios a lo largo de la bahía durante nueve años. A los nueve años de datos se aplicaron Funciones Empíricas Ortogonales para obtener sus principales modos de variabilidad espacial y temporal. El primer modo de variabilidad, modo 1, representó el 86% de la variabilidad total. La variabilidad espacial del modo 1 consistió en valores máximos de salinidad dentro de la bahía relativos a la entrada de la bahía. Este máximo dentro de la bahía es el rasgo principal que identifica un tapón de sal. La variabilidad temporal del modo 1 mostró valores máximos durante invierno y mínimos en verano relacionados a la estacionalidad de la descarga del rio Mississippi. Se concluye que el tapón de sal es generado por el pulso de agua dulce proveniente de la desembocadura del rio Mississippi localizado en la plataforma oceánica fuera de la bahía. Este pulso de agua dulce se mezcla con el agua oceánica resultando en una masa de agua con salinidad diluida. La masa de agua diluida es transportada por la Corriente Costera de Luisiana hacia la parte occidental del delta, bañando las bahías presentes en esta parte del delta entre ellas la bahía de Barataria. Este trabajo describe por primera vez la formación de un tapón de sal generado principalmente por una descarga de rio afuera de un estuario.
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Nugraha, Reza Satria, i Oliver Esteva Tumbarinu. "Enhancing Stratigraphic Framework Consistency Using Spectral Gamma-Ray Data". W SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204836-ms.
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Abstract Stratigraphic correlation is crucial for reservoir characterization; therefore, it requires more advanced methods and techniques to reduce the stratigraphic correlation uncertainty, especially when variation in lateral facies is high. The studied formations from bottom to top consist of fluvial to marginal marine X Formation, shallow marine Y Formation, and fluvial distributary channels to estuarine Z Formation. Spectral gamma-ray logs give additional consistent information on lithological composition that can support identification of boundary between formations within the stratigraphic framework. Wells with a full section of Y Formation, core, palynology, and spectral gamma-ray were selected as key wells. The top and base of the Y Formation were picked using conventional logs refined by a thorium/potassium (Th/K) ratio log and cross plot with core and palynology data as validations. The internal Y Formation markers were also picked with the aid of the Th/K cross plots. The top picking criteria from the key wells was implemented to the rest of the wells across the field with consistency. The uniform low Th/K ratio log (<3.5) across the Y Formation indicates illite as the dominant clay type, confirmed by X-ray diffraction (XRD) data with an average of more than 80%. The character is consistent with the interpreted depositional environment. This character makes the Y Formation stand out from the overlying Z and the underlying X formations. The change from X to Y Formation is defined by the decrease of the Th/K ratio log, from high kaolinite content to illite dominated environment. Inversely, the top of the Y Formation (base of Z) is indicated by the increase of the Th/K ratio log moving from shallow marine Y Formation to the fluvial-influenced Z Formation. The Th/K cross plot indicates different clusters amongst the studied formations and the internal Y zonation. The X Formation is located in the high Th and low K area where kaolinite is predominant, related to fluvial environment. The case is similar for the Z Formation but with more influence of mixed-clay type. The Y Formation shows clear clustering along the mixed-clay and illite window. Internal Y zonation displays, from bottom to top, an increasing K value within the clusters. This method provides a semi-quantitative interpretation to define the studied formations boundaries and the Y Formation internal zonation. This study has increased the consistency of the studied formations’ stratigraphic and structural framework. This consistency has, in turn, fine-tuned the structural framework and aided field development through better geosteering and lateral well placements. These results are a valuable starting point to refine and extend the work to other areas.