Articles | Volume 25, issue 9
15 Sep 2021
Technical note | 15 Sep 2021
Technical note: Effects of iron(II) on fluorescence properties of dissolved organic matter at circumneutral pH
Kun Jia et al.
No articles found.
Samuel T. Wilson, Alia N. Al-Haj, Annie Bourbonnais, Claudia Frey, Robinson W. Fulweiler, John D. Kessler, Hannah K. Marchant, Jana Milucka, Nicholas E. Ray, Parvadha Suntharalingam, Brett F. Thornton, Robert C. Upstill-Goddard, Thomas S. Weber, Damian L. Arévalo-Martínez, Hermann W. Bange, Heather M. Benway, Daniele Bianchi, Alberto V. Borges, Bonnie X. Chang, Patrick M. Crill, Daniela A. del Valle, Laura Farías, Samantha B. Joye, Annette Kock, Jabrane Labidi, Cara C. Manning, John W. Pohlman, Gregor Rehder, Katy J. Sparrow, Philippe D. Tortell, Tina Treude, David L. Valentine, Bess B. Ward, Simon Yang, and Leonid N. Yurganov
Biogeosciences, 17, 5809–5828,Short summary
The oceans are a net source of the major greenhouse gases; however there has been little coordination of oceanic methane and nitrous oxide measurements. The scientific community has recently embarked on a series of capacity-building exercises to improve the interoperability of dissolved methane and nitrous oxide measurements. This paper derives from a workshop which discussed the challenges and opportunities for oceanic methane and nitrous oxide research in the near future.
Cara C. Manning, Rachel H. R. Stanley, David P. Nicholson, Brice Loose, Ann Lovely, Peter Schlosser, and Bruce G. Hatcher
Biogeosciences, 16, 3351–3376,Short summary
We measured rates of biological activity and gas exchange in a Canadian estuary during ice melt. We quantified gas exchange using inert, deliberately released tracers and found that the gas transfer rate at > 90 % ice cover was 6 % of the rate for nearly ice-free conditions. We measured oxygen concentration and isotopic composition and used the data to detect changes in the rates of photosynthesis and respiration (autotrophy and heterotrophy) as the ice melted.
Samuel T. Wilson, Hermann W. Bange, Damian L. Arévalo-Martínez, Jonathan Barnes, Alberto V. Borges, Ian Brown, John L. Bullister, Macarena Burgos, David W. Capelle, Michael Casso, Mercedes de la Paz, Laura Farías, Lindsay Fenwick, Sara Ferrón, Gerardo Garcia, Michael Glockzin, David M. Karl, Annette Kock, Sarah Laperriere, Cliff S. Law, Cara C. Manning, Andrew Marriner, Jukka-Pekka Myllykangas, John W. Pohlman, Andrew P. Rees, Alyson E. Santoro, Philippe D. Tortell, Robert C. Upstill-Goddard, David P. Wisegarver, Gui-Ling Zhang, and Gregor Rehder
Biogeosciences, 15, 5891–5907,Short summary
To determine the variability between independent measurements of dissolved methane and nitrous oxide, seawater samples were analyzed by multiple laboratories. The results revealed the influences of the different parts of the analytical process, from the initial sample collection to the calculation of the final concentrations. Recommendations are made to improve dissolved methane and nitrous oxide measurements to help preclude future analytical discrepancies between laboratories.
Related subject area
Subject: Groundwater hydrology | Techniques and Approaches: Instruments and observation techniquesSpatiotemporal optimization of groundwater monitoring networks using data-driven sparse sensing methodsEvidence for high-elevation salar recharge and interbasin groundwater flow in the Western Cordillera of the Peruvian AndesThe evolution of stable silicon isotopes in a coastal carbonate aquifer on Rottnest Island, Western AustraliaDynamics of hydrological and geomorphological processes in evaporite karst at the eastern Dead Sea – a multidisciplinary studyUsing multiple methods to investigate the effects of land-use changes on groundwater recharge in a semi-arid areaIdentifying recharge under subtle ephemeral features in a flat-lying semi-arid region using a combined geophysical approachIsotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquiferTime-lapse cross-hole electrical resistivity tomography (CHERT) for monitoring seawater intrusion dynamics in a Mediterranean aquiferUnderstanding the relative importance of vertical and horizontal flow in ice-wedge polygonsGroundwater–glacier meltwater interaction in proglacial aquifersA review of methods for measuring groundwater–surface water exchange in braided riversError in hydraulic head and gradient time-series measurements: a quantitative appraisalThe effect of sediment thermal conductivity on vertical groundwater flux estimatesHydrogeological conceptual model of andesitic watersheds revealed by high-resolution heliborne geophysicsMicrobial community changes induced by Managed Aquifer Recharge activities: linking hydrogeological and biological processesApplication of the pore water stable isotope method and hydrogeological approaches to characterise a wetland systemComment on “Origin of water in the Badain Jaran Desert, China: new insight from isotopes” by Wu et al. (2017)Delineating multiple salinization processes in a coastal plain aquifer, northern China: hydrochemical and isotopic evidenceHydraulic characterisation of iron-oxide-coated sand and gravel based on nuclear magnetic resonance relaxation mode analysesUsing hydraulic head, chloride and electrical conductivity data to distinguish between mountain-front and mountain-block recharge to basin aquifersAquifer configuration and geostructural links control the groundwater quality in thin-bedded carbonate–siliciclastic alternations of the Hainich CZE, central GermanyA multi-tracer approach to constraining artesian groundwater discharge into an alluvial aquiferTransfer of environmental signals from the surface to the underground at Ascunsă Cave, RomaniaHalon-1301 – further evidence of its performance as an age tracer in New Zealand groundwaterElectrical resistivity dynamics beneath a fractured sedimentary bedrock riverbed in response to temperature and groundwater–surface water exchangeDetecting seasonal and long-term vertical displacement in the North China Plain using GRACE and GPSFlow dynamics in hyper-saline aquifers: hydro-geophysical monitoring and modelingInfluence of groundwater on distribution of dwarf wedgemussels (Alasmidonta heterodon) in the upper reaches of the Delaware River, northeastern USAQuantifying the influence of surface water–groundwater interaction on nutrient flux in a lowland karst catchmentIdentification of anthropogenic and natural inputs of sulfate into a karstic coastal groundwater system in northeast China: evidence from major ions, δ13CDIC and δ34SSO4Accelerated gravity testing of aquitard core permeability and implications at formation and regional scaleDetermining the stable isotope composition of pore water from saturated and unsaturated zone core: improvements to the direct vapour equilibration laser spectrometry methodAssessment of Halon-1301 as a groundwater age tracerIdentifying flood recharge and inter-aquifer connectivity using multiple isotopes in subtropical AustraliaTechnical Note: Field experiences using UV/VIS sensors for high-resolution monitoring of nitrate in groundwaterTimescales of regional circulation of saline fluids in continental crystalline rock aquifers (Armorican Massif, western France)A groundwater recharge perspective on locating tree plantations within low-rainfall catchments to limit water resource lossesIdentifying the origin and geochemical evolution of groundwater using hydrochemistry and stable isotopes in the Subei Lake basin, Ordos energy base, Northwestern ChinaGroundwater dynamics under water-saving irrigation and implications for sustainable water management in an oasis: Tarim River basin of western ChinaUsing hydrologic measurements to investigate free-phase gas ebullition in a Maine peatland, USASpatially resolved information on karst conduit flow from in-cave dye tracingThe usefulness of outcrop-analogue air-permeameter measurements for analysing aquifer heterogeneity: testing outcrop hydrogeological parameters with independent borehole dataInvestigating the spatio-temporal variability in groundwater and surface water interactions: a multi-technique approachTracing groundwater salinization processes in coastal aquifers: a hydrogeochemical and isotopic approach in the Na-Cl brackish waters of northwestern Sardinia, ItalyGaining and losing stream reaches have opposite hydraulic conductivity distribution patternsGroundwater–surface water interactions, vegetation dependencies and implications for water resources management in the semi-arid Hailiutu River catchment, China – a synthesisTeaching groundwater flow processes: connecting lecture to practical and field classesAssessing student understanding of physical hydrologyQuantifying aquifer properties and freshwater resource in coastal barriers: a hydrogeophysical approach applied at Sasihithlu (Karnataka state, India)Characterizing interactions between surface water and groundwater in the Jialu River basin using major ion chemistry and stable isotopes
Marc Ohmer, Tanja Liesch, and Andreas Wunsch
Hydrol. Earth Syst. Sci., 26, 4033–4053,Short summary
We present a data-driven approach to select optimal locations for groundwater monitoring wells. The applied approach can optimize the number of wells and their location for a network reduction (by ranking wells in order of their information content and reducing redundant) and extension (finding sites with great information gain) or both. It allows us to include a cost function to account for more/less suitable areas for new wells and can help to obtain maximum information content for a budget.
Odiney Alvarez-Campos, Elizabeth J. Olson, Lisa R. Welp, Marty D. Frisbee, Sebastián A. Zuñiga Medina, José Díaz Rodríguez, Wendy R. Roque Quispe, Carol I. Salazar Mamani, Midhuar R. Arenas Carrión, Juan Manuel Jara, Alexander Ccanccapa-Cartagena, and Chad T. Jafvert
Hydrol. Earth Syst. Sci., 26, 483–503,Short summary
We present results of a hydrologic study of groundwater recharge near the city of Arequipa, Peru. There are a number of springs below a high-elevation salar that show some chemical evidence of connectivity to the salar basin, possibly facilitated by faults in region. These results suggest that this salar basin is not a strictly terminal lake but that some interbasin groundwater flow exists. In addition, a high-elevation forest ecosystem seems important for groundwater recharge as well.
Ashley N. Martin, Karina Meredith, Andy Baker, Marc D. Norman, and Eliza Bryan
Hydrol. Earth Syst. Sci., 25, 3837–3853,Short summary
We measured the silicon isotopic composition of groundwater from Rottnest Island, Western Australia, to investigate water–rock interactions in a coastal aquifer. Silicon isotopic ratios varied spatially across the island and were related to secondary mineral formation and vertical mixing within the aquifer. We find that silicate dissolution occurs in the freshwater–seawater transition zone, supporting the recent recognition of submarine groundwater discharge in the oceanic silicon isotope cycle.
Djamil Al-Halbouni, Robert A. Watson, Eoghan P. Holohan, Rena Meyer, Ulrich Polom, Fernando M. Dos Santos, Xavier Comas, Hussam Alrshdan, Charlotte M. Krawczyk, and Torsten Dahm
Hydrol. Earth Syst. Sci., 25, 3351–3395,Short summary
The rapid decline of the Dead Sea level since the 1960s has provoked a dynamic reaction from the coastal groundwater system, with physical and chemical erosion creating subsurface voids and conduits. By combining remote sensing, geophysical methods, and numerical modelling at the Dead Sea’s eastern shore, we link groundwater flow patterns to the formation of surface stream channels, sinkholes and uvalas. Better understanding of this karst system will improve regional hazard assessment.
Shovon Barua, Ian Cartwright, P. Evan Dresel, and Edoardo Daly
Hydrol. Earth Syst. Sci., 25, 89–104,Short summary
We evaluate groundwater recharge rates in a semi-arid area that has undergone land-use changes. The widespread presence of old saline groundwater indicates that pre-land-clearing recharge rates were low and present-day recharge rates are still modest. The fluctuations of the water table and tritium activities reflect present-day recharge rates; however, the water table fluctuation estimates are unrealistically high, and this technique may not be suited for estimating recharge in semi-arid areas.
Brady A. Flinchum, Eddie Banks, Michael Hatch, Okke Batelaan, Luk J. M. Peeters, and Sylvain Pasquet
Hydrol. Earth Syst. Sci., 24, 4353–4368,Short summary
Identifying and quantifying recharge processes linked to ephemeral surface water features is challenging due to their episodic nature. We use a unique combination of well-established near-surface geophysical methods to provide evidence of a surface and groundwater connection in a flat, semi-arid region north of Adelaide, Australia. We show that a combined geophysical approach can provide a unique perspective that can help shape the hydrogeological conceptualization.
Karina T. Meredith, Andy Baker, Martin S. Andersen, Denis M. O'Carroll, Helen Rutlidge, Liza K. McDonough, Phetdala Oudone, Eliza Bryan, and Nur Syahiza Zainuddin
Hydrol. Earth Syst. Sci., 24, 2167–2178,Short summary
Dissolved organic carbon within groundwater and processes controlling it remain largely unknown. The average groundwater concentration at this coastal site was 5 times higher than the global median, doubling with depth, but with no change in chromatographic character. The lack of oxygen limited the rate of organic matter processing, leading to enhanced preservation. Changes in coastal hydrology could lead to the flux of unreacted organic carbon.
Andrea Palacios, Juan José Ledo, Niklas Linde, Linda Luquot, Fabian Bellmunt, Albert Folch, Alex Marcuello, Pilar Queralt, Philippe A. Pezard, Laura Martínez, Laura del Val, David Bosch, and Jesús Carrera
Hydrol. Earth Syst. Sci., 24, 2121–2139,Short summary
Coastal areas are highly populated and seawater intrusion endangers the already scarce freshwater resources. We use, for the first time, a geophysical experiment called cross-hole electrical resistivity tomography to monitor seawater intrusion dynamics. The technique relies on readings of rock and water electrical conductivity to detect salt in the aquifer. Two years of experiment allowed us to reveal variations in aquifer salinity due to natural seasonality, heavy-rain events and droughts.
Nathan A. Wales, Jesus D. Gomez-Velez, Brent D. Newman, Cathy J. Wilson, Baptiste Dafflon, Timothy J. Kneafsey, Florian Soom, and Stan D. Wullschleger
Hydrol. Earth Syst. Sci., 24, 1109–1129,Short summary
Rapid warming in the Arctic is causing increased permafrost temperatures and ground ice degradation. To study the effects of ice degradation on water distribution, tracer was applied to two end members of ice-wedge polygons – a ubiquitous landform in the Arctic. End member type was found to significantly affect water distribution as lower flux was observed with ice-wedge degradation. Results suggest ice degradation can influence partitioning of sequestered carbon as carbon dioxide or methane.
Brighid É. Ó Dochartaigh, Alan M. MacDonald, Andrew R. Black, Jez Everest, Paul Wilson, W. George Darling, Lee Jones, and Mike Raines
Hydrol. Earth Syst. Sci., 23, 4527–4539,Short summary
We provide evidence of high groundwater storage and flow in catchments with active glaciers. Groundwater is found within gravels at the front of glaciers and replenished by both ice melt and precipitation. We studied a glacier in Iceland for 3 years, characterising the aquifer properties and measuring groundwater, river flow and precipitation. The results are important for accurately measuring meltwater and show that groundwater can provide strategic water supplies in de-glaciating catchments.
Katie Coluccio and Leanne Kaye Morgan
Hydrol. Earth Syst. Sci., 23, 4397–4417,Short summary
Braided rivers are uncommon internationally but are important freshwater resources. However, there is limited understanding of how characteristics unique to braided rivers affect groundwater–surface water flow paths. This article reviews prior studies that have investigated groundwater–surface water interactions in these rivers and their associated aquifers to provide guidance on methodologies most suitable for future work in braided rivers and highlight gaps in current knowledge.
Gabriel C. Rau, Vincent E. A. Post, Margaret Shanafield, Torsten Krekeler, Eddie W. Banks, and Philipp Blum
Hydrol. Earth Syst. Sci., 23, 3603–3629,Short summary
The flow of water is often inferred from water levels and gradients whose measurements are considered trivial despite the many steps and complexity of the instruments involved. We systematically review the four measurement steps required and summarise the systematic errors. To determine the accuracy with which flow can be resolved, we quantify and propagate the random errors. Our results illustrate the limitations of current practice and provide concise recommendations to improve data quality.
Eva Sebok and Sascha Müller
Hydrol. Earth Syst. Sci., 23, 3305–3317,Short summary
Exchange fluxes between groundwater and surface waters can be quantified using temperature measurements from the upper sediment layers of streams and lakes assuming the thermal properties of sediments. This study quantified the natural variabiilty in sediment thermal conductivity in the vertical direction at the bed of surface waters and showed that fluxes can change by up to +/-75 % depending on using standard literature values or in situ measurements for sediment thermal conductivity.
Benoit Vittecoq, Pierre-Alexandre Reninger, Frédéric Lacquement, Guillaume Martelet, and Sophie Violette
Hydrol. Earth Syst. Sci., 23, 2321–2338,Short summary
Water resource management on volcanic islands is challenging and faces several issues. Taking advantage of new heliborne geophysical technology, correlated with borehole and spring data, we develop a watershed-scale conceptual model and demonstrate that permeability increases with age for the studied formations. Moreover, complex geological structures lead to preferential flow circulations and to discrepancy between topographical and hydrogeological watersheds, influencing river flow rates.
Carme Barba, Albert Folch, Núria Gaju, Xavier Sanchez-Vila, Marc Carrasquilla, Alba Grau-Martínez, and Maira Martínez-Alonso
Hydrol. Earth Syst. Sci., 23, 139–154,Short summary
Managed aquifer recharge allows increasing water resources and can be used to improve water quality. We assess the degradative capabilities of infiltrating pollutants by mapping the composition of microbial communities linked to periods of infiltration/drought. From samples of soil, surface and groundwater, we found some microbial species involved in the nitrogen and carbon cycles. Furthermore, we found that, during infiltration, microbial abundance rises, increasing degradative capabilities.
Katarina David, Wendy Timms, Catherine E. Hughes, Jagoda Crawford, and Dayna McGeeney
Hydrol. Earth Syst. Sci., 22, 6023–6041,Short summary
We investigated the wetland system classified as a threatened ecological community and found that organic-rich soil close to surfaces retains significant moisture necessary for ecosystems. At the base of the swamp an identified sand layer allows relatively rapid drainage and lateral groundwater interaction. Evaporation estimated from stable water isotopes from sediments indicated that groundwater contribution to the swamp is significant in dry periods, supporting ecosystems when water is scarce.
Lucheng Zhan, Jiansheng Chen, Ling Li, and David A. Barry
Hydrol. Earth Syst. Sci., 22, 4449–4454,Short summary
Using the arithmetic averages of precipitation isotope values, Wu et al. (2017) concluded that the Badain Jaran Desert (BJD) groundwater is recharged by modern local meteoric water. However, based on weighted mean precipitation isotope values, our further analysis shows that modern precipitation on the Qilian Mountains is more likely to be the main source of the groundwater and lake water in the BJD, as found. We believe this comment provides an important improvement for their study.
Dongmei Han and Matthew J. Currell
Hydrol. Earth Syst. Sci., 22, 3473–3491,Short summary
Based on hydrochemical and isotopic analysis, we investigated the potential hydrogeological processes responsible for the increasing groundwater salinity in the coastal aquifer of Yang–Dai River coastal plain, northern China. Seawater intrusion is the major aspect and can be caused by vertical infiltration along the riverbed at the downstream areas, and lateral inflow into fresh aquifer. Geothermal water also makes a significant contribution to increasing the groundwater salinity.
Stephan Costabel, Christoph Weidner, Mike Müller-Petke, and Georg Houben
Hydrol. Earth Syst. Sci., 22, 1713–1729,Short summary
Laboratory experiments using water-filled sand and gravel samples with significant contents of iron oxide coatings were performed to identify the relationship between effective hydraulic radius and nuclear magnetic resonance (NMR) response. Our interpretation approach for the NMR data leads to reliable estimates of hydraulic conductivity without calibration, but is limited to coarse material for physical reasons. An NMR-based observation system for iron clogging in boreholes is planned.
Etienne Bresciani, Roger H. Cranswick, Eddie W. Banks, Jordi Batlle-Aguilar, Peter G. Cook, and Okke Batelaan
Hydrol. Earth Syst. Sci., 22, 1629–1648,Short summary
This article tackles the problem of finding the origin of groundwater in basin aquifers adjacent to mountains. In particular, we aim to determine whether the recharge occurs predominantly through stream infiltration along the mountain front or through subsurface flow from the mountain. To this end, we discuss the use of routinely measured variables: hydraulic head, chloride and electrical conductivity. A case study from Australia demonstrates the approach.
Bernd Kohlhepp, Robert Lehmann, Paul Seeber, Kirsten Küsel, Susan E. Trumbore, and Kai U. Totsche
Hydrol. Earth Syst. Sci., 21, 6091–6116,
Charlotte P. Iverach, Dioni I. Cendón, Karina T. Meredith, Klaus M. Wilcken, Stuart I. Hankin, Martin S. Andersen, and Bryce F. J. Kelly
Hydrol. Earth Syst. Sci., 21, 5953–5969,Short summary
This study uses a multi-tracer geochemical approach to determine the extent of artesian groundwater discharge into an economically important alluvial aquifer. We compare estimates for artesian discharge into the alluvial aquifer derived from water balance modelling and geochemical data to show that there is considerable divergence in the results. The implications of this work involve highlighting that geochemical data should be used as a critical component of water budget assessments.
Virgil Drăguşin, Sorin Balan, Dominique Blamart, Ferenc Lázár Forray, Constantin Marin, Ionuţ Mirea, Viorica Nagavciuc, Iancu Orăşeanu, Aurel Perşoiu, Laura Tîrlă, Alin Tudorache, and Marius Vlaicu
Hydrol. Earth Syst. Sci., 21, 5357–5373,
Monique Beyer, Uwe Morgenstern, Rob van der Raaij, and Heather Martindale
Hydrol. Earth Syst. Sci., 21, 4213–4231,Short summary
The determination of groundwater age can aid characterization of aquifers, providing information on groundwater mixing, flow, volume, and recharge rates. Here we assess a recently discovered groundwater age tracer, Halon-1301. Its performance as an age tracer is assessed against six other well-established, widely used age tracers in 302 groundwater samples. We show Halon-1301 reliably inferred age, thus potentially becoming a useful groundwater age tracer where other tracers are compromised.
Colby M. Steelman, Celia S. Kennedy, Donovan C. Capes, and Beth L. Parker
Hydrol. Earth Syst. Sci., 21, 3105–3123,Short summary
The Eramosa River flows along a fractured sedimentary bedrock aquifer with large subsurface channel features. This study examines the potential for groundwater–surface water exchange beneath the fractured bedrock riverbed and the impacts of seasonal and intraseasonal flow system transience on the geoelectrical properties of the rock. Our results will have implications to the conceptual understanding of groundwater–surface water interaction within fractured bedrock river environments.
Linsong Wang, Chao Chen, Jinsong Du, and Tongqing Wang
Hydrol. Earth Syst. Sci., 21, 2905–2922,Short summary
The North China Plain (NCP), as the interest region in this study, is one of the most uniformly and extensively altered areas due to overexploitation of groundwater by humans. Here, we use GRACE and GPS to study the seasonal and long-term mass change and its resulting vertical displacement. We also removed the vertical rates, which are induced by terrestrial water storage (TWS) from GPS-derived data to obtain the corrected vertical velocities caused by tectonic movement and human activities.
Klaus Haaken, Gian Piero Deidda, Giorgio Cassiani, Rita Deiana, Mario Putti, Claudio Paniconi, Carlotta Scudeler, and Andreas Kemna
Hydrol. Earth Syst. Sci., 21, 1439–1454,Short summary
The paper presents a general methodology that will help understand how freshwater and saltwater may interact in natural porous media, with a particular view at practical applications such as the storage of freshwater underground in critical areas, e.g., semi-arid zones around the Mediterranean sea. The methodology is applied to a case study in Sardinia and shows how a mix of advanced monitoring and mathematical modeling tremendously advance our understanding of these systems.
Donald O. Rosenberry, Martin A. Briggs, Emily B. Voytek, and John W. Lane
Hydrol. Earth Syst. Sci., 20, 4323–4339,Short summary
The remaining populations of the endangered dwarf wedgemussel (DWM) (Alasmidonta heterodon) in the upper Delaware River, northeastern USA, were thought to be located in areas of substantial groundwater discharge to the river. Physical, thermal, and geophysical methods applied at several spatial scales indicate that DWM are located within or directly downstream of areas of substantial groundwater discharge to the river. DWM may depend on groundwater discharge for their survival.
T. McCormack, O. Naughton, P. M. Johnston, and L. W. Gill
Hydrol. Earth Syst. Sci., 20, 2119–2133,Short summary
In this study, the influence of surface water–groundwater interaction on the nutrient flux in a lowland karst catchment in western Ireland was investigated with the aid of alkalinity sampling and a hydrological model. Results indicated that denitrification within a number of ephemeral lakes is the main process reducing nitrogen concentrations within the turloughs, whereas phosphorus loss is thought to occur mostly via sedimentation and subsequent soil deposition.
Dongmei Han, Xianfang Song, and Matthew J. Currell
Hydrol. Earth Syst. Sci., 20, 1983–1999,Short summary
We report new data for carbon and sulfur isotopes of the groundwater flow system in a coastal carbonate aquifer of northeast China. It shows how these can be used to determine the major processes controlling sulfate cycling and transport. Hopefully the study will be of broad international interest, and is expected to improve the understanding of techniques to determine impacts on groundwater quality and flow, leading to improved groundwater protection and monitoring strategies.
W. A. Timms, R. Crane, D. J. Anderson, S. Bouzalakos, M. Whelan, D. McGeeney, P. F. Rahman, and R. I. Acworth
Hydrol. Earth Syst. Sci., 20, 39–54,Short summary
Low permeability sediments and rock can leak slowly, yet can act as important barriers to flow for resource development and for waste sequestration. Relatively rapid and reliable hydraulic tests of "tight" geological materials are possible by accelerating gravity. Results from geotechnical centrifuge testing of drill core and in situ pore pressure monitoring were compared with a regional flow model, and considered in the context of inherent geological variability at site and formation scale.
M. J. Hendry, E. Schmeling, L. I. Wassenaar, S. L. Barbour, and D. Pratt
Hydrol. Earth Syst. Sci., 19, 4427–4440,Short summary
Improvements and limitations to the measurement δ2H and δ18O of pore waters in geologic core samples using laser spectrometry are presented. These included the use of a δ2H spike to assess the extent of drill fluid contamination and the effect of storage time and type of sample bag on pore water values.
M. Beyer, R. van der Raaij, U. Morgenstern, and B. Jackson
Hydrol. Earth Syst. Sci., 19, 2775–2789,Short summary
We assess the potential of Halon-1301 as a new groundwater age tracer, which had not been assessed in detail. We determine Halon-1301 and infer age in 17 New Zealand groundwater samples and various modern waters. Halon-1301 reliably inferred age in 71% of the sites within 1 SD of the ages inferred from tritium and SF6. The remaining (anoxic) waters show reduced concentrations of Halon-1301 along with even further reduced concentrations of CFCs. The reason(s) for this need to be further assessed.
A. C. King, M. Raiber, D. I. Cendón, M. E. Cox, and S. E. Hollins
Hydrol. Earth Syst. Sci., 19, 2315–2335,
M. Huebsch, F. Grimmeisen, M. Zemann, O. Fenton, K. G. Richards, P. Jordan, A. Sawarieh, P. Blum, and N. Goldscheider
Hydrol. Earth Syst. Sci., 19, 1589–1598,Short summary
Two different in situ spectrophotometers, which were used in the field to determine highly time resolved nitrate-nitrogen (NO3-N) concentrations at two distinct spring discharge sites, are compared: a double and a multiple wavelength spectrophotometer. The objective of the study was to review the hardware options, determine ease of calibration, accuracy, influence of additional substances and to assess positive and negative aspects of the two sensors as well as troubleshooting and trade-offs.
A. Armandine Les Landes, L. Aquilina, P. Davy, V. Vergnaud-Ayraud, and C. Le Carlier
Hydrol. Earth Syst. Sci., 19, 1413–1426,Short summary
The crystalline rock aquifers of the Armorican Massif present clear evidence of a marine origin of the saline component in the fluids on the regional scale. High chloride concentrations are attributed to three past marine transgressions. The relationship between chloride concentration and transgression age provides constraints for the timescales of fluid circulation. This time frame is useful information for developing conceptual models of the paleo-functioning of Armorican aquifers.
J. F. Dean, J. A. Webb, G. E. Jacobsen, R. Chisari, and P. E. Dresel
Hydrol. Earth Syst. Sci., 19, 1107–1123,Short summary
This paper examines modern and historical groundwater recharge rates to determine the impacts of reforestation in south-eastern Australia. This study shows that over both the long and short term, groundwater recharge in the study area occurs predominantly in the lower catchment areas. The results of this study show that spatial variations in recharge are important considerations for locating tree plantations, especially when looking to conserve water for downstream users in low rainfall regions.
F. Liu, X. Song, L. Yang, Y. Zhang, D. Han, Y. Ma, and H. Bu
Hydrol. Earth Syst. Sci., 19, 551–565,Short summary
Due to intensive groundwater exploitation in energy base, significant changes in groundwater system will take place. This research identified the origin and geochemical evolution of groundwater in the Subei Lake basin under the influence of human activity, enhancing the knowledge of lake basins in groundwater discharge area and providing valuable groundwater information for decision makers to formulate sustainable groundwater management strategies for other similar lake basins in arid regions.
Z. Zhang, H. Hu, F. Tian, X. Yao, and M. Sivapalan
Hydrol. Earth Syst. Sci., 18, 3951–3967,
C. E. Bon, A. S. Reeve, L. Slater, and X. Comas
Hydrol. Earth Syst. Sci., 18, 953–965,
U. Lauber, W. Ufrecht, and N. Goldscheider
Hydrol. Earth Syst. Sci., 18, 435–445,
B. Rogiers, K. Beerten, T. Smeekens, D. Mallants, M. Gedeon, M. Huysmans, O. Batelaan, and A. Dassargues
Hydrol. Earth Syst. Sci., 17, 5155–5166,
N. P. Unland, I. Cartwright, M. S. Andersen, G. C. Rau, J. Reed, B. S. Gilfedder, A. P. Atkinson, and H. Hofmann
Hydrol. Earth Syst. Sci., 17, 3437–3453,
G. Mongelli, S. Monni, G. Oggiano, M. Paternoster, and R. Sinisi
Hydrol. Earth Syst. Sci., 17, 2917–2928,
X. Chen, W. Dong, G. Ou, Z. Wang, and C. Liu
Hydrol. Earth Syst. Sci., 17, 2569–2579,
Y. Zhou, J. Wenninger, Z. Yang, L. Yin, J. Huang, L. Hou, X. Wang, D. Zhang, and S. Uhlenbrook
Hydrol. Earth Syst. Sci., 17, 2435–2447,
V. Hakoun, N. Mazzilli, S. Pistre, and H. Jourde
Hydrol. Earth Syst. Sci., 17, 1975–1984,
J. A. Marshall, A. J. Castillo, and M. B. Cardenas
Hydrol. Earth Syst. Sci., 17, 829–836,
J.-M. Vouillamoz, J. Hoareau, M. Grammare, D. Caron, L. Nandagiri, and A. Legchenko
Hydrol. Earth Syst. Sci., 16, 4387–4400,
L. Yang, X. Song, Y. Zhang, D. Han, B. Zhang, and D. Long
Hydrol. Earth Syst. Sci., 16, 4265–4277,
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The effect of soluble reduced iron, Fe(II), on fluorescence data (excitation–emission matrix spectra parsed using parallel factor analysis) is difficult to quantitatively assign. We added varying quantities of Fe(II) into groundwater from an anaerobic aquifer. We showed that the overall fluorescence intensity decreased nonlinearly as Fe(II) increased from 1 to 306 mg L-1 but that the parallel factor analysis component distribution was relatively insensitive to Fe(II) concentration.
The effect of soluble reduced iron, Fe(II), on fluorescence data (excitation–emission matrix...