Articles | Volume 20, issue 8
https://doi.org/10.5194/hess-20-3077-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/hess-20-3077-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Assessing land–ocean connectivity via submarine groundwater discharge (SGD) in the Ria Formosa Lagoon (Portugal): combining radon measurements and stable isotope hydrology
Carlos Rocha
CORRESPONDING AUTHOR
Biogeochemistry Research Group, Geography Department, School of
Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
Cristina Veiga-Pires
Biogeochemistry Research Group, Geography Department, School of
Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
CIMA-Marine and Environmental Research Center, Universidade do
Algarve, Portugal
Jan Scholten
Institute of Geosciences, University of Kiel, Germany
Kay Knoeller
UFZ, Helmholtz Centre for Environmental Research Leipzig/Halle,
Germany
Darren R. Gröcke
Department of Earth Sciences, Durham University, South Road, Durham,
County Durham, DH1 3LE, UK
Liliana Carvalho
Biogeochemistry Research Group, Geography Department, School of
Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
CIMA-Marine and Environmental Research Center, Universidade do
Algarve, Portugal
Jaime Anibal
Biogeochemistry Research Group, Geography Department, School of
Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
CIMA-Marine and Environmental Research Center, Universidade do
Algarve, Portugal
Jean Wilson
Biogeochemistry Research Group, Geography Department, School of
Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
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Christina Franziska Radtke, Xiaoqiang Yang, Christin Müller, Jarno Rouhiainen, Ralf Merz, Stefanie R. Lutz, Paolo Benettin, Hong Wei, and Kay Knöller
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-109, https://doi.org/10.5194/hess-2024-109, 2024
Revised manuscript under review for HESS
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Most studies assume no difference between transit times of water and nitrate, because nitrate is transported by water. With an 8-year high-frequency dataset of isotopic signatures of both, water and nitrate, and a transit time model, we show the temporal varying difference of nitrate and water transit times. This finding is highly relevant for applied future research related to nutrient dynamics in landscapes under anthropogenic forcing and for managing impacts of nitrate on aquatic ecosystems.
Michael Rode, Jörg Tittel, Frido Reinstorf, Michael Schubert, Kay Knöller, Benjamin Gilfedder, Florian Merensky-Pöhlein, and Andreas Musolff
Hydrol. Earth Syst. Sci., 27, 1261–1277, https://doi.org/10.5194/hess-27-1261-2023, https://doi.org/10.5194/hess-27-1261-2023, 2023
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Agricultural catchments show elevated phosphorus (P) concentrations during summer low flow. In an agricultural stream, we found that phosphorus in groundwater was a major source of stream water phosphorus during low flow, and stream sediments derived from farmland are unlikely to have increased stream phosphorus concentrations during low water. We found no evidence that riparian wetlands contributed to soluble reactive (SR) P loads. Agricultural phosphorus was largely buffered in the soil zone.
Erin L. McClymont, Michael J. Bentley, Dominic A. Hodgson, Charlotte L. Spencer-Jones, Thomas Wardley, Martin D. West, Ian W. Croudace, Sonja Berg, Darren R. Gröcke, Gerhard Kuhn, Stewart S. R. Jamieson, Louise Sime, and Richard A. Phillips
Clim. Past, 18, 381–403, https://doi.org/10.5194/cp-18-381-2022, https://doi.org/10.5194/cp-18-381-2022, 2022
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Sea ice is important for our climate system and for the unique ecosystems it supports. We present a novel way to understand past Antarctic sea-ice ecosystems: using the regurgitated stomach contents of snow petrels, which nest above the ice sheet but feed in the sea ice. During a time when sea ice was more extensive than today (24 000–30 000 years ago), we show that snow petrel diet had varying contributions of fish and krill, which we interpret to show changing sea-ice distribution.
Laia Comas-Bru, Sandy P. Harrison, Martin Werner, Kira Rehfeld, Nick Scroxton, Cristina Veiga-Pires, and SISAL working group members
Clim. Past, 15, 1557–1579, https://doi.org/10.5194/cp-15-1557-2019, https://doi.org/10.5194/cp-15-1557-2019, 2019
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We use an updated version of the Speleothem Isotopes Synthesis and Analysis (SISAL) database and palaeoclimate simulations generated using the ECHAM5-wiso isotope-enabled climate model to provide a protocol for using speleothem isotopic data for model evaluation, including screening the observations and the optimum period for the modern observational baseline. We also illustrate techniques through which the absolute isotopic values during any time period could be used for model evaluation.
Nnenesi A. Kgabi, Eliot Atekwana, Johanna Ithindi, Martha Uugwanga, Kay Knoeller, Lebogang Motsei, Manny Mathuthu, Gideon Kalumbu, Hilma R. Amwele, and Rian Uusizi
Proc. IAHS, 378, 93–98, https://doi.org/10.5194/piahs-378-93-2018, https://doi.org/10.5194/piahs-378-93-2018, 2018
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High salinity in the groundwater of Cuvelai-Etosha Basin is caused by the weathering of Kalahari sediments, not the evaporation of water on surface prior to groundwater recharge. Low salinity in the Kuiseb Basin derives from rapid recharge by unevaporated rain and limited weathering of the crystalline rocks. Thus, groundwater quality in the two Basins is controlled by water-rock interaction at the surface and in the groundwater aquifer.
Niels A. G. M. van Helmond, Appy Sluijs, Nina M. Papadomanolaki, A. Guy Plint, Darren R. Gröcke, Martin A. Pearce, James S. Eldrett, João Trabucho-Alexandre, Ireneusz Walaszczyk, Bas van de Schootbrugge, and Henk Brinkhuis
Biogeosciences, 13, 2859–2872, https://doi.org/10.5194/bg-13-2859-2016, https://doi.org/10.5194/bg-13-2859-2016, 2016
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Over the past decades large changes have been observed in the biogeographical dispersion of marine life resulting from climate change. To better understand present and future trends it is important to document and fully understand the biogeographical response of marine life during episodes of environmental change in the geological past.
Here we investigate the response of phytoplankton, the base of the marine food web, to a rapid cold spell, interrupting greenhouse conditions during the Cretaceous.
Related subject area
Subject: Coasts and Estuaries | Techniques and Approaches: Instruments and observation techniques
River plastic transport affected by tidal dynamics
Monitoring tidal hydrology in coastal wetlands with the “Mini Buoy”: applications for mangrove restoration
Combining resistivity and frequency domain electromagnetic methods to investigate submarine groundwater discharge in the littoral zone
Combining continuous spatial and temporal scales for SGD investigations using UAV-based thermal infrared measurements
Analysis of data characterizing tide and current fluxes in coastal basins
Can mussels be used as sentinel organisms for characterization of pollution in urban water systems?
Turbidity in the fluvial Gironde Estuary (southwest France) based on 10-year continuous monitoring: sensitivity to hydrological conditions
Flooding in river mouths: human caused or natural events? Five centuries of flooding events in the SW Netherlands, 1500–2000
Determining slack tide with a GPS receiver on an anchored buoy
Ground-penetrating radar insight into a coastal aquifer: the freshwater lens of Borkum Island
Seasonal stratification and property distributions in a tropical estuary (Cochin estuary, west coast, India)
Suspended sediment load in the tidal zone of an Indonesian river
Deepwater Horizon oil spill impacts on Alabama beaches
Monitoring water quality in estuarine environments: lessons from the MAGEST monitoring program in the Gironde fluvial-estuarine system
Louise J. Schreyers, Tim H. M. van Emmerik, Thanh-Khiet L. Bui, Khoa L. van Thi, Bart Vermeulen, Hong-Q. Nguyen, Nicholas Wallerstein, Remko Uijlenhoet, and Martine van der Ploeg
Hydrol. Earth Syst. Sci., 28, 589–610, https://doi.org/10.5194/hess-28-589-2024, https://doi.org/10.5194/hess-28-589-2024, 2024
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River plastic emissions into the ocean are of global concern, but the transfer dynamics between fresh water and the marine environment remain poorly understood. We developed a simple Eulerian approach to estimate the net and total plastic transport in tidal rivers. Applied to the Saigon River, Vietnam, we found that net plastic transport amounted to less than one-third of total transport, highlighting the need to better integrate tidal dynamics in plastic transport and emission models.
Thorsten Balke, Alejandra Vovides, Christian Schwarz, Gail L. Chmura, Cai Ladd, and Mohammad Basyuni
Hydrol. Earth Syst. Sci., 25, 1229–1244, https://doi.org/10.5194/hess-25-1229-2021, https://doi.org/10.5194/hess-25-1229-2021, 2021
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Restoration of intertidal wetlands such as mangroves and saltmarshes requires accurate local data on tidal flooding and current velocities. We present the application of a low-cost underwater float equipped with an acceleration data logger, the Mini Buoy, to monitor inundation and tidal currents in intertidal environments. We demonstrate how this tool can be directly applied in hydrological site suitability assessments prior to mangrove restoration in tropical SE Asia.
Marieke Paepen, Daan Hanssens, Philippe De Smedt, Kristine Walraevens, and Thomas Hermans
Hydrol. Earth Syst. Sci., 24, 3539–3555, https://doi.org/10.5194/hess-24-3539-2020, https://doi.org/10.5194/hess-24-3539-2020, 2020
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Fresh groundwater can flow to oceans and seas, possibly adding nutrients and pollutants to coastal ecosystems. For the first time, three complementary (salinity-sensitive) geophysical methods are combined to delineate the outflow in a very dynamic coastal environment. This provides temporal and spatial information on the salt- and freshwater distribution on land, in the intertidal zone, and offshore and visualizes the fresh-groundwater discharge around the low-water line at De Westhoek, Belgium.
Ulf Mallast and Christian Siebert
Hydrol. Earth Syst. Sci., 23, 1375–1392, https://doi.org/10.5194/hess-23-1375-2019, https://doi.org/10.5194/hess-23-1375-2019, 2019
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Submarine groundwater discharge is highly variable in spatial and temporal terms. With a novel approach using a hovering drone over a predefined location which recorded 670 surface temperatures images over a period of 167 s, we are able to (i) enhance focused SGD patterns otherwise camouflaged by strong lateral flow dynamics, (ii) show size variation of up to 155 % (focused SGD) and 600 % (diffuse SGD), and (iii) reveal short-term periodicity of the order of 20 to 78 s for diffuse SGD.
Elvira Armenio, Francesca De Serio, and Michele Mossa
Hydrol. Earth Syst. Sci., 21, 3441–3454, https://doi.org/10.5194/hess-21-3441-2017, https://doi.org/10.5194/hess-21-3441-2017, 2017
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The paper aims to investigate current and tide correlation in a basin named Mar Piccolo, located in the inner part of the Ionian Sea. It is considered highly vulnerable, being exposed to urban and industrial discharges as well as to intense naval traffic. A continuous monitoring action of the principal hydrodynamic parameters could be a useful managing tool, considering that the diffusion and dispersions of polluting tracers is strictly connected to currents, tide, and waves propagation.
Elke S. Reichwaldt and Anas Ghadouani
Hydrol. Earth Syst. Sci., 20, 2679–2689, https://doi.org/10.5194/hess-20-2679-2016, https://doi.org/10.5194/hess-20-2679-2016, 2016
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We assessed if nitrogen stable isotopes in mussels are a suitable indicator, capable of resolving spatial and temporal variability of nutrient pollution in an urban estuary. Our results highlight the value of using stable isotope analysis as an integrative tool to establish an understanding of local processes and pollution levels in theses urban aquatic systems. We suggest that mussels can become a robust tool for the detection of emerging anthropogenic pollutants of concern in urban water systems.
I. Jalón-Rojas, S. Schmidt, and A. Sottolichio
Hydrol. Earth Syst. Sci., 19, 2805–2819, https://doi.org/10.5194/hess-19-2805-2015, https://doi.org/10.5194/hess-19-2805-2015, 2015
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This study aims to analyse for the first time suspended sediment dynamics in the fluvial Gironde through a unique set of a 10-year continuous turbidity record. We demonstrate the following: the interest of turbidity-discharge hysteresis loops to evaluate the presence of sediment depositions; the relationships between features of the turbidity maximum zone (TMZ) and river flow; and the definition of hydrological indicators of the persistence and concentration of the TMZ.
A. M. J. de Kraker
Hydrol. Earth Syst. Sci., 19, 2673–2684, https://doi.org/10.5194/hess-19-2673-2015, https://doi.org/10.5194/hess-19-2673-2015, 2015
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Natural floodings caused by storm floods also have important human components determining how disastrous they could be.
Man-made floodings during warfare were only successful if natural conditions and factors were fully used.
Strategic floodings during the 16th-17th centuries dramatically changed landscapes, from which valueble lessons were learnt to perfect this strategy in the 18th and 19th centuries.
M. Valk, H. H. G. Savenije, C. C. J. M. Tiberius, and W. M. J. Luxemburg
Hydrol. Earth Syst. Sci., 18, 2599–2613, https://doi.org/10.5194/hess-18-2599-2014, https://doi.org/10.5194/hess-18-2599-2014, 2014
J. Igel, T. Günther, and M. Kuntzer
Hydrol. Earth Syst. Sci., 17, 519–531, https://doi.org/10.5194/hess-17-519-2013, https://doi.org/10.5194/hess-17-519-2013, 2013
A. Shivaprasad, J. Vinita, C. Revichandran, P. D. Reny, M. P. Deepak, K. R. Muraleedharan, and K. R. Naveen Kumar
Hydrol. Earth Syst. Sci., 17, 187–199, https://doi.org/10.5194/hess-17-187-2013, https://doi.org/10.5194/hess-17-187-2013, 2013
F. A. Buschman, A. J. F. Hoitink, S. M. de Jong, P. Hoekstra, H. Hidayat, and M. G. Sassi
Hydrol. Earth Syst. Sci., 16, 4191–4204, https://doi.org/10.5194/hess-16-4191-2012, https://doi.org/10.5194/hess-16-4191-2012, 2012
J. S. Hayworth, T. P. Clement, and J. F. Valentine
Hydrol. Earth Syst. Sci., 15, 3639–3649, https://doi.org/10.5194/hess-15-3639-2011, https://doi.org/10.5194/hess-15-3639-2011, 2011
H. Etcheber, S. Schmidt, A. Sottolichio, E. Maneux, G. Chabaux, J.-M. Escalier, H. Wennekes, H. Derriennic, M. Schmeltz, L. Quéméner, M. Repecaud, P. Woerther, and P. Castaing
Hydrol. Earth Syst. Sci., 15, 831–840, https://doi.org/10.5194/hess-15-831-2011, https://doi.org/10.5194/hess-15-831-2011, 2011
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Short summary
We combine radon and stable isotopes in water to determine total submarine groundwater discharge (SGD) in the Ria Formosa and discriminate its component modes. We show that tidal action filters the entire water volume in the lagoon through local beaches 3.5 times a year, driving an estimated 350Ton nitrogen/year into the system. Conversely, fresh groundwater is discharged into the lagoon only occasionally, adding ~ 61 Ton nitrogen/year, but is capable of driving new production in the system.
We combine radon and stable isotopes in water to determine total submarine groundwater discharge...