Radium isotopes as submarine groundwater discharge (SGD) tracers: Review and recommendations

Earth-Science Reviews, Journal Year: 2021, Volume and Issue: 220, P. 103681 - 103681

Published: May 14, 2021

Submarine groundwater discharge (SGD) is now recognized as an important process of the hydrological cycle worldwide and plays a major role conveyor dissolved compounds to ocean. Naturally occurring radium isotopes (223Ra, 224Ra, 226Ra 228Ra) are widely employed geochemical tracers in marine environments. Whilst Ra were initially predominantly applied study open ocean processes fluxes across continental margins, their most common application environment has undoubtedly become identification quantification SGD. This review focuses on SGD associated inputs water solutes coastal In addition, we i) controlling enrichment depletion seawater; ii) systematics estimate using iii) summarize additional applications studies. We also provide some considerations that will help refine estimates identify critical knowledge gaps research needs related current use tracers.

Language: Английский

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Conceptual uncertainties in groundwater and porewater fluxes estimated by radon and radium mass balances

Limnology and Oceanography, Journal Year: 2021, Volume and Issue: 66(4), P. 1237 - 1255

Published: Jan. 8, 2021

Abstract Radium isotopes and radon are routinely used as tracers to quantify groundwater porewater fluxes into coastal freshwater systems. However, uncertainties associated with the determination of tracer flux often poorly addressed neglect all potential errors conceptualization system (i.e., conceptual uncertainties). In this study, we assess magnitude some key related radium inputs supplied by a waterbody (La Palme Lagoon, France). This uncertainty assessment is through single model ensemble approach, where mass balance run multiple times variable sets assumptions approaches for parameters determined sensitivity test. particular, linked concentration, diffusive fluxes, evasion atmosphere, change inventory over time were considered. The further constrained using comparison independent methods: (1) 224 Ra (2) 222 Rn balances in overlying waters, (3) deficit sediments, (4) fluid‐salt numerical transport model. We demonstrate that commonly major source on estimation or they need be taken account when balances. absence general framework assessing these uncertainties, study provides practical approach evaluate

Language: Английский

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The social implications of Submarine Groundwater Discharge from an Ecosystem Services perspective: A systematic review

Earth-Science Reviews, Journal Year: 2021, Volume and Issue: 221, P. 103742 - 103742

Published: July 17, 2021

Submarine Groundwater Discharge (SGD) is recognized as a fundamental hydrological process that supports many coastal biogeochemical cycles and social-ecological systems. However, very little has been investigated about how SGD affects society and, specifically, human well-being. This study systematically examines the published scientific literature on social implications of by using an Ecosystem Service (ES) perspective. Coastal services provided ecosystems dependent are analyzed clustered in four main categories Services (i.e., Provisioning, Supporting, Regulating Cultural), which turn divided into subcategories defined outcomes. allows identifying discussing both benefits threats to societies resulting from From 1532 articles initially reviewed, most frequently mentioned category was supporting (835) due mainstream trend focus role influencing cycles. Conversely, cultural ES were only 49 cases, should not necessarily be interpreted lack research or interest this topic, but type references often found grey literature. A detailed publication review additionally conducted, 114 case-studies 96 different locations worldwide reported cases had Our also shows types can have multiple synergies trade-offs between them, unequal impacts among stakeholder groups. Overall, identifies gaps related well opportunities for further studies, while developing analytical framework relies approach guide future SGD.

Language: Английский

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A State-Of-The-Art Perspective on the Characterization of Subterranean Estuaries at the Regional Scale

Frontiers in Earth Science, Journal Year: 2021, Volume and Issue: 9

Published: May 14, 2021

Subterranean estuaries the, subsurface mixing zones of terrestrial groundwater and seawater, substantially influence solute fluxes to the oceans. Solutes brought by from land solutes sea can undergo biogeochemical reactions. These are often mediated microbes controlled reactions with coastal sediments, determine composition fluids discharging STEs (i.e., submarine discharge), which may have consequences showing in ecosystems. While at local scale (meters), processes been intensively studied, impact subterranean estuary on ocean remains poorly constrained regional (kilometers). In present communication, we review that occur STEs, focusing mainly fluid flow transformations nitrogen, phosphorus, carbon, sulfur trace metals. We highlight spatio-temporal dynamics measurable manifestations those processes. The objective this contribution is provide a perspective how tracer studies, geophysical methods, remote sensing hydrogeological modeling could exploit such estimate regional-scale ocean.

Language: Английский

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Guidelines and Limits for the Quantification of Ra Isotopes and Related Radionuclides With the Radium Delayed Coincidence Counter (RaDeCC)

Journal of Geophysical Research Oceans, Journal Year: 2020, Volume and Issue: 125(4)

Published: March 27, 2020

Abstract The Radium Delayed Coincidence Counter (RaDeCC) is one of the most extensively used equipment for measuring 223 Ra and 224 activities in water sediment samples. Samples are placed a closed He‐circulation system that carries Rn produced by decay to scintillation cell. Each alpha recorded cell routed an electronic delayed coincidence which enables discrimination Ra. In this study, measurement quantification methods using RaDeCC assessed through analyses registered data different systems worldwide set simulations. Results work indicate equations correct cross‐talk interferences only valid given range ratios between isotopes. Above certain limits specified these corrections may significantly overestimate (up ~40% 30%, respectively), as well their parents 227 Ac 228 Th. High 226 also produce overestimation due buildup 222 Rn, especially when long measurements with low performed. An improved method quantify from developed study. Wethus provide new guidelines appropriate Ra, Ac, Th, system.

Language: Английский

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Mobility and accessibility of Zn, Pb, and As in abandoned mine tailings of northwestern Mexico

Environmental Science and Pollution Research, Journal Year: 2020, Volume and Issue: 27(21), P. 26605 - 26620

Published: May 5, 2020

Language: Английский

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Applicability of Landsat 8 thermal infrared sensor for identifying submarine groundwater discharge springs in the Mediterranean Sea basin

Hydrology and earth system sciences, Journal Year: 2021, Volume and Issue: 25(9), P. 4789 - 4805

Published: Sept. 2, 2021

Abstract. Submarine groundwater discharge (SGD) has received increasing attention over the past 2 decades as a source of nutrients, trace elements and ocean pollutants that may alter coastal biogeochemical cycles. Assessing SGD flows their impact on marine environments is difficult task, since it not easy to identify measure these water discharging into sea. The aim this study demonstrate significant usefulness freely available thermal infrared (TIR) imagery Landsat 8 sensor (TIRS) an exploratory tool for identifying springs worldwide, from local regional scales, long-term analysis. use satellite data technique in seawater based identification thermally anomalous plumes obtained contrasts between sea surface water. In study, we TIR remote sensing (TIR-RS) provided by at scale discuss principle limiting factors using studies. was developed karstic aquifers Mediterranean Sea basin during different seasons under diverse meteorological conditions. Although demonstrates useful method karst both locally regionally, include technical limitations, geological hydrogeological characteristics, environmental conditions geomorphology.

Language: Английский

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New perspectives on the use of 224Ra/228Ra and 222Rn/226Ra activity ratios in groundwater studies

Journal of Hydrology, Journal Year: 2021, Volume and Issue: 596, P. 126043 - 126043

Published: Feb. 2, 2021

Language: Английский

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Metals in coastal groundwater systems under anthropogenic pressure: a synthesis of behavior, drivers, and emerging threats

Limnology and Oceanography Letters, Journal Year: 2024, Volume and Issue: 9(4), P. 388 - 410

Published: June 3, 2024

Abstract Submarine groundwater discharge (SGD) dynamically links land‐ and ocean‐derived chemical constituents, such as metals, in the coastal ocean. While many metals are sediment‐bound, changing environmental conditions, particularly along coast, may lead to increased release of their dissolved more bioavailable form. Here, we review metal behavior, speciation, drivers mobilization environment under anthropogenic influence. We also model global contamination risk ocean via SGD considering hydrogeologic pressures, where tropical regions with high population density, SGD, acid sulfate soils (4% coast) present highest risk. Although most studies focus on other analytes, nutrients, this demonstrates importance a critical pathway for reach rapidly conditions.

Language: Английский

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Extreme precipitation events induce high fluxes of groundwater and associated nutrients to coastal ocean

Hydrology and earth system sciences, Journal Year: 2022, Volume and Issue: 26(18), P. 4619 - 4635

Published: Sept. 20, 2022

Abstract. Current studies of submarine groundwater discharge (SGD) are commonly conducted under aquifer baseflow conditions, neglecting the influence episodic events that can significantly increase supply nutrients and water. This limits our understanding social, biogeochemical, ecological impacts SGD. In this study, we evaluated an extreme precipitation event (EPE) on magnitude To do so, three seawater sampling campaigns were performed at a Mediterranean ephemeral stream-dominated basin after EPE (∼ 90 mm in few hours) conditions. Results indicate flows 1 order higher than those The SGD induced by EPEs, which only take place days per year, represented up to one third annual associated study site. work accentuates need account for increases water when aiming provide reliable estimates, particularly current context climate change, since occurrence such is expected worldwide.

Language: Английский

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