Articles | Volume 19, issue 3
https://doi.org/10.5194/bg-19-931-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-19-931-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Feb 2022
Research article |
| 15 Feb 2022
| 15 Feb 2022
Nutrient transport and transformation in macrotidal estuaries of the French Atlantic coast: a modeling approach using the Carbon-Generic Estuarine Model
Xi Wei
CORRESPONDING AUTHOR
UMR Metis 7619, Sorbonne Université, CNRS EPHE, 4 Place Jussieu, Paris 75005, France
Josette Garnier
CORRESPONDING AUTHOR
UMR Metis 7619, Sorbonne Université, CNRS EPHE, 4 Place Jussieu, Paris 75005, France
Vincent Thieu
UMR Metis 7619, Sorbonne Université, CNRS EPHE, 4 Place Jussieu, Paris 75005, France
Paul Passy
UMR 8586 PRODIG, Université de Paris, 8 rue Albert Einstein, 75013 Paris, France
Romain Le Gendre
Ecosystèmes et Aquaculture Durable, Unité de Recherche Lagons, IFREMER, Nouméa 98897, New Caledonia
Gilles Billen
UMR Metis 7619, Sorbonne Université, CNRS EPHE, 4 Place Jussieu, Paris 75005, France
Maia Akopian
Department of Research and Scientific Support, French Biodiversity Agency (OFB), 5 Square Félix Nadar, 94300 Vincennes, France
Goulven Gildas Laruelle
Department of Geosciences, Environment and Society, Université Libre de Bruxelles, Brussels 1050, Belgium
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Manon Maisonnier, Maoyuan Feng, David Bastviken, Sandra Arndt, Ronny Lauerwald, Aidin Jabbari, Goulven Gildas Laruelle, Murray D. MacKay, Zeli Tan, Wim Thiery, and Pierre Regnier
EGUsphere, https://doi.org/10.5194/egusphere-2025-1306, https://doi.org/10.5194/egusphere-2025-1306, 2025
This preprint is open for discussion and under review for Earth System Dynamics (ESD).
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A new process-based modelling framework, FLaMe v1.0 (Fluxes of Lake Methane version 1.0), is developed to simulate methane (CH4) emissions from lakes at large scales. FLaMe couples the dynamics of organic carbon, oxygen and methane in lakes and rests on an innovative, computationally efficient lake clustering approach for the simulation of CH4 emissions across a large number of lakes. The model evaluation suggests that FLaMe captures the sub-annual and spatial variability of CH4 emissions well.
Camille Minaudo, Andras Abonyi, Carles Alcaraz, Jacob Diamond, Nicholas J. K. Howden, Michael Rode, Estela Romero, Vincent Thieu, Fred Worrall, Qian Zhang, and Xavier Benito
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-58, https://doi.org/10.5194/essd-2025-58, 2025
Preprint under review for ESSD
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Many waterbodies undergo nutrient decline globally, called oligotrophication, but a comprehensive dataset to understand ecosystem responses is lacking. The OLIGOTREND database comprises multi-decadal chlorophyll-a and nutrient timeseries from rivers, lakes, and estuaries with 4.3 million observations from 1,894 unique measurement locations. The database provides empirical evidence for oligotrophication responses with a spatial and temporal coverage exceeding previous efforts.
Romain Le Gendre, David Varillon, Sylvie Fiat, Régis Hocdé, Antoine De Ramon N'Yeurt, Jérôme Aucan, Sophie Cravatte, Maxime Duphil, Alexandre Ganachaud, Baptiste Gaudron, Elodie Kestenare, Vetea Liao, Bernard Pelletier, Alexandre Peltier, Anne-Lou Schaefer, Thomas Trophime, Simon Van Wynsberge, Yves Dandonneau, Michel Allenbach, and Christophe Menkes
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-394, https://doi.org/10.5194/essd-2024-394, 2024
Revised manuscript under review for ESSD
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Due to ocean warming, coral reef ecosystems are strongly impacted with dystrophic events and corals experiencing increasing frequencies of bleaching events. In-situ observation remains the best alternative for accurate characterization of trends and extremes in these shallow environments. This paper presents the coastal temperature dataset of the ReefTEMPS monitoring network which spreads over multiple Pacific Island Countries and Territories (PICTS) in the Western and Central South Pacific.
Oriane Bruyère, Romain Le Gendre, Vetea Liao, and Serge Andréfouët
Earth Syst. Sci. Data, 16, 667–679, https://doi.org/10.5194/essd-16-667-2024, https://doi.org/10.5194/essd-16-667-2024, 2024
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During 2019–2020, the lagoon and forereefs of Gambier Island (French Polynesia) were monitored with oceanographic instruments to measure lagoon hydrodynamics and ocean–lagoon water exchanges. Gambier Island is a key black pearl producer and the study goal was to understand the processes influencing spat collection of pearl oyster Pinctada margaritifera, the species used to produce black pearls. The data set is provided to address local pearl farming questions and other investigations as well.
Alizée Roobaert, Pierre Regnier, Peter Landschützer, and Goulven G. Laruelle
Earth Syst. Sci. Data, 16, 421–441, https://doi.org/10.5194/essd-16-421-2024, https://doi.org/10.5194/essd-16-421-2024, 2024
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The quantification of the coastal air–sea CO2 exchange (FCO2) has improved in recent years, but its multiannual variability remains unclear. This study, based on interpolated observations, reconstructs the longest global time series of coastal FCO2 (1982–2020). Results show the coastal ocean acts as a CO2 sink, with increasing intensity over time. This new coastal FCO2-product allows establishing regional carbon budgets and provides new constraints for closing the global carbon cycle.
Oriane Bruyère, Romain Le Gendre, Mathilde Chauveau, Bertrand Bourgeois, David Varillon, John Butscher, Thomas Trophime, Yann Follin, Jérôme Aucan, Vetea Liao, and Serge Andréfouët
Earth Syst. Sci. Data, 15, 5553–5573, https://doi.org/10.5194/essd-15-5553-2023, https://doi.org/10.5194/essd-15-5553-2023, 2023
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During 2018–2022, four pearl farming Tuamotu atolls (French Polynesia) were studied with oceanographic instruments to measure lagoon hydrodynamics and ocean-lagoon water exchanges. The goal was to gain knowledge on the processes influencing the spat collection of the pearl oyster Pinctada margaritifera, the species used to produce black pearls. A worldwide unique oceanographic atoll data set is provided to address local pearl farming questions and other fundamental and applied investigations.
Oriane Bruyère, Benoit Soulard, Hugues Lemonnier, Thierry Laugier, Morgane Hubert, Sébastien Petton, Térence Desclaux, Simon Van Wynsberge, Eric Le Tesson, Jérôme Lefèvre, Franck Dumas, Jean-François Kayara, Emmanuel Bourassin, Noémie Lalau, Florence Antypas, and Romain Le Gendre
Earth Syst. Sci. Data, 14, 5439–5462, https://doi.org/10.5194/essd-14-5439-2022, https://doi.org/10.5194/essd-14-5439-2022, 2022
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From 2014 to 2021, extensive monitoring of hydrodynamics was deployed within five contrasted lagoons of New Caledonia during austral summers. These coastal physical observations encompassed unmonitored lagoons and captured eight major atmospheric events ranging from tropical depression to category 4 cyclone. The main objectives were to characterize the processes controlling hydrodynamics of these lagoons and record the signature of extreme events on land–lagoon–ocean continuum functioning.
Alizée Roobaert, Laure Resplandy, Goulven G. Laruelle, Enhui Liao, and Pierre Regnier
Ocean Sci., 18, 67–88, https://doi.org/10.5194/os-18-67-2022, https://doi.org/10.5194/os-18-67-2022, 2022
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This study uses a global oceanic model to investigate the seasonal dynamics of the sea surface partial pressure of CO2 (pCO2) in the global coastal ocean. Our method quantifies the respective effects of thermal changes, biological activity, ocean circulation and freshwater fluxes on the temporal pCO2 variations. The performance of our model is also evaluated against a data product derived from observations to identify coastal regions where our approach is most robust.
Amanda R. Fay, Luke Gregor, Peter Landschützer, Galen A. McKinley, Nicolas Gruber, Marion Gehlen, Yosuke Iida, Goulven G. Laruelle, Christian Rödenbeck, Alizée Roobaert, and Jiye Zeng
Earth Syst. Sci. Data, 13, 4693–4710, https://doi.org/10.5194/essd-13-4693-2021, https://doi.org/10.5194/essd-13-4693-2021, 2021
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The movement of carbon dioxide from the atmosphere to the ocean is estimated using surface ocean carbon (pCO2) measurements and an equation including variables such as temperature and wind speed; the choices of these variables lead to uncertainties. We introduce the SeaFlux ensemble which provides carbon flux maps calculated in a consistent manner, thus reducing uncertainty by using common choices for wind speed and a set definition of "global" coverage.
Peter Landschützer, Goulven G. Laruelle, Alizee Roobaert, and Pierre Regnier
Earth Syst. Sci. Data, 12, 2537–2553, https://doi.org/10.5194/essd-12-2537-2020, https://doi.org/10.5194/essd-12-2537-2020, 2020
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In recent years, multiple estimates of the global air–sea CO2 flux emerged from upscaling shipboard pCO2 measurements. They are however limited to the open-ocean domain and do not consider the coastal ocean, i.e. a significant marine sink for CO2. We build towards an integrated pCO2 product that combines both the open-ocean and coastal-ocean domain and focus on the evaluation of the common overlap area of these products and how well the aquatic continuum is represented in the new climatology.
Marielle Saunois, Ann R. Stavert, Ben Poulter, Philippe Bousquet, Josep G. Canadell, Robert B. Jackson, Peter A. Raymond, Edward J. Dlugokencky, Sander Houweling, Prabir K. Patra, Philippe Ciais, Vivek K. Arora, David Bastviken, Peter Bergamaschi, Donald R. Blake, Gordon Brailsford, Lori Bruhwiler, Kimberly M. Carlson, Mark Carrol, Simona Castaldi, Naveen Chandra, Cyril Crevoisier, Patrick M. Crill, Kristofer Covey, Charles L. Curry, Giuseppe Etiope, Christian Frankenberg, Nicola Gedney, Michaela I. Hegglin, Lena Höglund-Isaksson, Gustaf Hugelius, Misa Ishizawa, Akihiko Ito, Greet Janssens-Maenhout, Katherine M. Jensen, Fortunat Joos, Thomas Kleinen, Paul B. Krummel, Ray L. Langenfelds, Goulven G. Laruelle, Licheng Liu, Toshinobu Machida, Shamil Maksyutov, Kyle C. McDonald, Joe McNorton, Paul A. Miller, Joe R. Melton, Isamu Morino, Jurek Müller, Fabiola Murguia-Flores, Vaishali Naik, Yosuke Niwa, Sergio Noce, Simon O'Doherty, Robert J. Parker, Changhui Peng, Shushi Peng, Glen P. Peters, Catherine Prigent, Ronald Prinn, Michel Ramonet, Pierre Regnier, William J. Riley, Judith A. Rosentreter, Arjo Segers, Isobel J. Simpson, Hao Shi, Steven J. Smith, L. Paul Steele, Brett F. Thornton, Hanqin Tian, Yasunori Tohjima, Francesco N. Tubiello, Aki Tsuruta, Nicolas Viovy, Apostolos Voulgarakis, Thomas S. Weber, Michiel van Weele, Guido R. van der Werf, Ray F. Weiss, Doug Worthy, Debra Wunch, Yi Yin, Yukio Yoshida, Wenxin Zhang, Zhen Zhang, Yuanhong Zhao, Bo Zheng, Qing Zhu, Qiuan Zhu, and Qianlai Zhuang
Earth Syst. Sci. Data, 12, 1561–1623, https://doi.org/10.5194/essd-12-1561-2020, https://doi.org/10.5194/essd-12-1561-2020, 2020
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Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. We have established a consortium of multidisciplinary scientists under the umbrella of the Global Carbon Project to synthesize and stimulate new research aimed at improving and regularly updating the global methane budget. This is the second version of the review dedicated to the decadal methane budget, integrating results of top-down and bottom-up estimates.
Audrey Marescaux, Vincent Thieu, Nathalie Gypens, Marie Silvestre, and Josette Garnier
Hydrol. Earth Syst. Sci., 24, 2379–2398, https://doi.org/10.5194/hess-24-2379-2020, https://doi.org/10.5194/hess-24-2379-2020, 2020
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Rivers have been recognized as an active part of the carbon cycle where transformations are associated with CO2 outgassing. To understand it, we propose a modeling approach with the biogeochemical model, pyNuts-Riverstrahler. We implemented it on the human-impacted Seine River. Sources of carbon to the river were characterized by field measurements in groundwater and in wastewater. Outgassing was the most important in streams, and peaks were simulated downstream of wastewater treatment effluent.
Alizée Roobaert, Goulven G. Laruelle, Peter Landschützer, and Pierre Regnier
Biogeosciences, 15, 1701–1720, https://doi.org/10.5194/bg-15-1701-2018, https://doi.org/10.5194/bg-15-1701-2018, 2018
Goulven G. Laruelle, Peter Landschützer, Nicolas Gruber, Jean-Louis Tison, Bruno Delille, and Pierre Regnier
Biogeosciences, 14, 4545–4561, https://doi.org/10.5194/bg-14-4545-2017, https://doi.org/10.5194/bg-14-4545-2017, 2017
Jakob Zscheischler, Miguel D. Mahecha, Valerio Avitabile, Leonardo Calle, Nuno Carvalhais, Philippe Ciais, Fabian Gans, Nicolas Gruber, Jens Hartmann, Martin Herold, Kazuhito Ichii, Martin Jung, Peter Landschützer, Goulven G. Laruelle, Ronny Lauerwald, Dario Papale, Philippe Peylin, Benjamin Poulter, Deepak Ray, Pierre Regnier, Christian Rödenbeck, Rosa M. Roman-Cuesta, Christopher Schwalm, Gianluca Tramontana, Alexandra Tyukavina, Riccardo Valentini, Guido van der Werf, Tristram O. West, Julie E. Wolf, and Markus Reichstein
Biogeosciences, 14, 3685–3703, https://doi.org/10.5194/bg-14-3685-2017, https://doi.org/10.5194/bg-14-3685-2017, 2017
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Here we synthesize a wide range of global spatiotemporal observational data on carbon exchanges between the Earth surface and the atmosphere. A key challenge was to consistently combining observational products of terrestrial and aquatic surfaces. Our primary goal is to identify today’s key uncertainties and observational shortcomings that would need to be addressed in future measurement campaigns or expansions of in situ observatories.
Goulven Gildas Laruelle, Nicolas Goossens, Sandra Arndt, Wei-Jun Cai, and Pierre Regnier
Biogeosciences, 14, 2441–2468, https://doi.org/10.5194/bg-14-2441-2017, https://doi.org/10.5194/bg-14-2441-2017, 2017
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The C-GEM generic reactive-transport model is applied to each tidal estuary of the US East Coast. Seasonal simulations are performed, which allows the understanding and quantification of the effect of the estuarine filter on the lateral fluxes of carbon coming from rivers.
Chiara Volta, Goulven Gildas Laruelle, Sandra Arndt, and Pierre Regnier
Hydrol. Earth Syst. Sci., 20, 991–1030, https://doi.org/10.5194/hess-20-991-2016, https://doi.org/10.5194/hess-20-991-2016, 2016
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A generic estuarine model is applied to three idealized tidal estuaries representing the main hydro-geometrical estuarine classes. The study provides insight into the estuarine biogeochemical dynamics, in particular the air-water CO2/sub> flux, as well as the potential response to future environmental changes and to uncertainties in model parameter values. We believe that our approach could help improving upscaling strategies to better integrate estuaries in regional/global biogeochemical studies.
G. G. Laruelle, R. Lauerwald, J. Rotschi, P. A. Raymond, J. Hartmann, and P. Regnier
Biogeosciences, 12, 1447–1458, https://doi.org/10.5194/bg-12-1447-2015, https://doi.org/10.5194/bg-12-1447-2015, 2015
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This study quantifies the exchange of carbon dioxide (CO2) between the atmosphere and the land-ocean aquatic continuum (LOAC) of the northeast North American coast, which consists of rivers, estuaries, and the coastal ocean. Our analysis reveals significant variations of the flux intensity both in time and space across the study area. Ice cover, snowmelt, and the intensity of the estuarine filter are identified as important control factors of the CO2 exchange along the LOAC.
C. Volta, S. Arndt, H. H. G. Savenije, G. G. Laruelle, and P. Regnier
Geosci. Model Dev., 7, 1271–1295, https://doi.org/10.5194/gmd-7-1271-2014, https://doi.org/10.5194/gmd-7-1271-2014, 2014
G. G. Laruelle, H. H. Dürr, R. Lauerwald, J. Hartmann, C. P. Slomp, N. Goossens, and P. A. G. Regnier
Hydrol. Earth Syst. Sci., 17, 2029–2051, https://doi.org/10.5194/hess-17-2029-2013, https://doi.org/10.5194/hess-17-2029-2013, 2013
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Biogeochemistry: Modelling, Aquatic
Mixing, spatial resolution and argon saturation in a suite of coupled general ocean circulation biogeochemical models off Mauritania
Efficiency metrics for ocean alkalinity enhancements under responsive and prescribed atmospheric pCO2 conditions
Changes in Arctic Ocean plankton community structure and trophic dynamics on seasonal to interannual timescales
Global impact of benthic denitrification on marine N2 fixation and primary production simulated by a variable-stoichiometry Earth system model
Modeling the contribution of micronekton diel vertical migrations to carbon export in the mesopelagic zone
Killing the predator: impacts of highest-predator mortality on the global-ocean ecosystem structure
Hydrodynamic and biochemical impacts on the development of hypoxia in the Louisiana–Texas shelf – Part 1: roles of nutrient limitation and plankton community
Validation of the coupled physical–biogeochemical ocean model NEMO–SCOBI for the North Sea–Baltic Sea system
Investigating ecosystem connections in the shelf sea environment using complex networks
Seasonal and interannual variability of the pelagic ecosystem and of the organic carbon budget in the Rhodes Gyre (eastern Mediterranean): influence of winter mixing
How much do bacterial growth properties and biodegradable dissolved organic matter control water quality at low flow?
Methane emissions from Arctic landscapes during 2000–2015: an analysis with land and lake biogeochemistry models
Including filter-feeding gelatinous macrozooplankton in a global marine biogeochemical model: model–data comparison and impact on the ocean carbon cycle
Riverine impact on future projections of marine primary production and carbon uptake
Subsurface oxygen maximum in oligotrophic marine ecosystems: mapping the interaction between physical and biogeochemical processes
Quantifying biological carbon pump pathways with a data-constrained mechanistic model ensemble approach
Assessing the spatial and temporal variability of methylmercury biogeochemistry and bioaccumulation in the Mediterranean Sea with a coupled 3D model
Hydrodynamic and biochemical impacts on the development of hypoxia in the Louisiana–Texas shelf – Part 2: statistical modeling and hypoxia prediction
Modelling the effects of benthic fauna on carbon, nitrogen and phosphorus dynamics in the Baltic Sea
Improved prediction of dimethyl sulfide (DMS) distributions in the northeast subarctic Pacific using machine-learning algorithms
A modelling study of temporal and spatial pCO2 variability on the biologically active and temperature-dominated Scotian Shelf
Modeling the marine chromium cycle: new constraints on global-scale processes
New insights into large-scale trends of apparent organic matter reactivity in marine sediments and patterns of benthic carbon transformation
Evaluation of ocean dimethylsulfide concentration and emission in CMIP6 models
Zooplankton mortality effects on the plankton community of the northern Humboldt Current System: sensitivity of a regional biogeochemical model
Multi-compartment kinetic–allometric (MCKA) model of radionuclide bioaccumulation in marine fish
Impact of bottom trawling on sediment biogeochemistry: a modelling approach
Cyanobacteria blooms in the Baltic Sea: a review of models and facts
Arctic Ocean acidification over the 21st century co-driven by anthropogenic carbon increases and freshening in the CMIP6 model ensemble
Modeling silicate–nitrate–ammonium co-limitation of algal growth and the importance of bacterial remineralization based on an experimental Arctic coastal spring bloom culture study
Role of jellyfish in the plankton ecosystem revealed using a global ocean biogeochemical model
Extreme event waves in marine ecosystems: an application to Mediterranean Sea surface chlorophyll
Use of optical absorption indices to assess seasonal variability of dissolved organic matter in Amazon floodplain lakes
The role of sediment-induced light attenuation on primary production during Hurricane Gustav (2008)
Quantifying spatiotemporal variability in zooplankton dynamics in the Gulf of Mexico with a physical–biogeochemical model
One size fits all? Calibrating an ocean biogeochemistry model for different circulations
Assessing the temporal scale of deep-sea mining impacts on sediment biogeochemistry
Seasonal patterns of surface inorganic carbon system variables in the Gulf of Mexico inferred from a regional high-resolution ocean biogeochemical model
Oxygen dynamics and evaluation of the single-station diel oxygen model across contrasting geologies
Oceanic CO2 outgassing and biological production hotspots induced by pre-industrial river loads of nutrients and carbon in a global modeling approach
Global trends in marine nitrate N isotopes from observations and a neural network-based climatology
Merging bio-optical data from Biogeochemical-Argo floats and models in marine biogeochemistry
Model constraints on the anthropogenic carbon budget of the Arctic Ocean
Modeling oceanic nitrate and nitrite concentrations and isotopes using a 3-D inverse N cycle model
Biogeochemical response of the Mediterranean Sea to the transient SRES-A2 climate change scenario
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Heiner Dietze and Ulrike Löptien
Biogeosciences, 22, 1215–1236, https://doi.org/10.5194/bg-22-1215-2025, https://doi.org/10.5194/bg-22-1215-2025, 2025
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We introduce argon saturation as a prognostic variable in a suite of coupled general ocean circulation biogeochemical models off Mauritania. Our results indicate that the effect of increasing the spatial horizontal model resolutions from 12 km to 1.5 km leads to changes comparable to other infamous spurious effects of state-of-the-art numerical advection numerics.
Michael D. Tyka
Biogeosciences, 22, 341–353, https://doi.org/10.5194/bg-22-341-2025, https://doi.org/10.5194/bg-22-341-2025, 2025
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Marine CO2 removal (mCDR) is a promising technology for removing legacy emissions from the atmosphere. Its indirect nature makes it difficult to assess experimentally; instead one relies heavily on simulation. Many past papers have treated the atmosphere as non-responsive to the intervention studied. We show that even under these simplified assumptions, the increase in ocean CO2 inventory is equal to the equivalent quantity of direct CO2 removals occurring over time, in a realistic atmosphere.
Gabriela Negrete-García, Jessica Y. Luo, Colleen M. Petrik, Manfredi Manizza, and Andrew D. Barton
Biogeosciences, 21, 4951–4973, https://doi.org/10.5194/bg-21-4951-2024, https://doi.org/10.5194/bg-21-4951-2024, 2024
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The Arctic Ocean experiences significant seasonal and year-to-year changes, impacting marine plankton populations. Using a plankton community model, we studied these effects on plankton communities and their influence on fish production. Our findings revealed earlier plankton blooms, shifts towards more carnivorous zooplankton, and increased fishery potential during summertime, especially in warmer years with less ice, highlighting the delicate balance of Arctic ecosystems.
Na Li, Christopher J. Somes, Angela Landolfi, Chia-Te Chien, Markus Pahlow, and Andreas Oschlies
Biogeosciences, 21, 4361–4380, https://doi.org/10.5194/bg-21-4361-2024, https://doi.org/10.5194/bg-21-4361-2024, 2024
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N is a crucial nutrient that limits phytoplankton growth in large ocean areas. The amount of oceanic N is governed by the balance of N2 fixation and denitrification. Here we incorporate benthic denitrification into an Earth system model with variable particulate stoichiometry. Our model compares better to the observed surface nutrient distributions, marine N2 fixation, and primary production. Benthic denitrification plays an important role in marine N and C cycling and hence the global climate.
Hélène Thibault, Frédéric Ménard, Jeanne Abitbol-Spangaro, Jean-Christophe Poggiale, and Séverine Martini
EGUsphere, https://doi.org/10.5194/egusphere-2024-2074, https://doi.org/10.5194/egusphere-2024-2074, 2024
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Micronekton significantly impacts oceanic carbon transport, yet often overlooked. Using a trait-based model, we simulated their diel vertical migrations and carbon production, revealing size, taxonomy, light and primary production as key factors. In temperate regions, micronekton influenced greatly the transport efficiency in summer. Future research must focus on micronekton metabolism and dynamics, considering global warming and their potential exploitation.
David Talmy, Eric Carr, Harshana Rajakaruna, Selina Våge, and Anne Willem Omta
Biogeosciences, 21, 2493–2507, https://doi.org/10.5194/bg-21-2493-2024, https://doi.org/10.5194/bg-21-2493-2024, 2024
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The structure of plankton communities is central to global cycles of carbon, nitrogen, and other elements. This study explored the sensitivity of different assumptions about highest-predator mortality in ecosystem models with contrasting food web structures. In the context of environmental data, we find support for models assuming a density-dependent mortality of the highest predator, irrespective of assumed food web structure.
Yanda Ou and Z. George Xue
Biogeosciences, 21, 2385–2424, https://doi.org/10.5194/bg-21-2385-2024, https://doi.org/10.5194/bg-21-2385-2024, 2024
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Developed for the Gulf of Mexico (2006–2020), a 3D hydrodynamic–biogeochemical model validated against in situ data reveals the impact of nutrients and plankton diversity on dissolved oxygen dynamics. It highlights the role of physical processes, sediment oxygen consumption, and nutrient distribution in shaping bottom oxygen levels and hypoxia. The model underscores the importance of complex plankton interactions for understanding primary production and hypoxia evolution.
Itzel Ruvalcaba Baroni, Elin Almroth-Rosell, Lars Axell, Sam T. Fredriksson, Jenny Hieronymus, Magnus Hieronymus, Sandra-Esther Brunnabend, Matthias Gröger, Ivan Kuznetsov, Filippa Fransner, Robinson Hordoir, Saeed Falahat, and Lars Arneborg
Biogeosciences, 21, 2087–2132, https://doi.org/10.5194/bg-21-2087-2024, https://doi.org/10.5194/bg-21-2087-2024, 2024
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The health of the Baltic and North seas is threatened due to high anthropogenic pressure; thus, different methods to assess the status of these regions are urgently needed. Here, we validated a novel model simulating the ocean dynamics and biogeochemistry of the Baltic and North seas that can be used to create future climate and nutrient scenarios, contribute to European initiatives on de-eutrophication, and provide water quality advice and support on nutrient load reductions for both seas.
Ieuan Higgs, Jozef Skákala, Ross Bannister, Alberto Carrassi, and Stefano Ciavatta
Biogeosciences, 21, 731–746, https://doi.org/10.5194/bg-21-731-2024, https://doi.org/10.5194/bg-21-731-2024, 2024
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A complex network is a way of representing which parts of a system are connected to other parts. We have constructed a complex network based on an ecosystem–ocean model. From this, we can identify patterns in the structure and areas of similar behaviour. This can help to understand how natural, or human-made, changes will affect the shelf sea ecosystem, and it can be used in multiple future applications such as improving modelling, data assimilation, or machine learning.
Joelle Habib, Caroline Ulses, Claude Estournel, Milad Fakhri, Patrick Marsaleix, Mireille Pujo-Pay, Marine Fourrier, Laurent Coppola, Alexandre Mignot, Laurent Mortier, and Pascal Conan
Biogeosciences, 20, 3203–3228, https://doi.org/10.5194/bg-20-3203-2023, https://doi.org/10.5194/bg-20-3203-2023, 2023
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The Rhodes Gyre, eastern Mediterranean Sea, is the main Levantine Intermediate Water formation site. In this study, we use a 3D physical–biogeochemical model to investigate the seasonal and interannual variability of organic carbon dynamics in the gyre. Our results show its autotrophic nature and its high interannual variability, with enhanced primary production, downward exports, and onward exports to the surrounding regions during years marked by intense heat losses and deep mixed layers.
Masihullah Hasanyar, Thomas Romary, Shuaitao Wang, and Nicolas Flipo
Biogeosciences, 20, 1621–1633, https://doi.org/10.5194/bg-20-1621-2023, https://doi.org/10.5194/bg-20-1621-2023, 2023
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The results of this study indicate that biodegradable dissolved organic matter is responsible for oxygen depletion at low flow during summer seasons when heterotrophic bacterial activity is so intense. Therefore, the dissolved organic matter must be well measured in the water monitoring networks in order to have more accurate water quality models. It also advocates for high-frequency data collection for better quantification of the uncertainties related to organic matter.
Xiangyu Liu and Qianlai Zhuang
Biogeosciences, 20, 1181–1193, https://doi.org/10.5194/bg-20-1181-2023, https://doi.org/10.5194/bg-20-1181-2023, 2023
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We are among the first to quantify methane emissions from inland water system in the pan-Arctic. The total CH4 emissions are 36.46 Tg CH4 yr−1 during 2000–2015, of which wetlands and lakes were 21.69 Tg yr−1 and 14.76 Tg yr−1, respectively. By using two non-overlap area change datasets with land and lake models, our simulation avoids small lakes being counted twice as both lake and wetland, and it narrows the gap between two different methods used to quantify regional CH4 emissions.
Corentin Clerc, Laurent Bopp, Fabio Benedetti, Meike Vogt, and Olivier Aumont
Biogeosciences, 20, 869–895, https://doi.org/10.5194/bg-20-869-2023, https://doi.org/10.5194/bg-20-869-2023, 2023
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Gelatinous zooplankton play a key role in the ocean carbon cycle. In particular, pelagic tunicates, which feed on a wide size range of prey, produce rapidly sinking detritus. Thus, they efficiently transfer carbon from the surface to the depths. Consequently, we added these organisms to a marine biogeochemical model (PISCES-v2) and evaluated their impact on the global carbon cycle. We found that they contribute significantly to carbon export and that this contribution increases with depth.
Shuang Gao, Jörg Schwinger, Jerry Tjiputra, Ingo Bethke, Jens Hartmann, Emilio Mayorga, and Christoph Heinze
Biogeosciences, 20, 93–119, https://doi.org/10.5194/bg-20-93-2023, https://doi.org/10.5194/bg-20-93-2023, 2023
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We assess the impact of riverine nutrients and carbon (C) on projected marine primary production (PP) and C uptake using a fully coupled Earth system model. Riverine inputs alleviate nutrient limitation and thus lessen the projected PP decline by up to 0.7 Pg C yr−1 globally. The effect of increased riverine C may be larger than the effect of nutrient inputs in the future on the projected ocean C uptake, while in the historical period increased nutrient inputs are considered the largest driver.
Valeria Di Biagio, Stefano Salon, Laura Feudale, and Gianpiero Cossarini
Biogeosciences, 19, 5553–5574, https://doi.org/10.5194/bg-19-5553-2022, https://doi.org/10.5194/bg-19-5553-2022, 2022
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The amount of dissolved oxygen in the ocean is the result of interacting physical and biological processes. Oxygen vertical profiles show a subsurface maximum in a large part of the ocean. We used a numerical model to map this subsurface maximum in the Mediterranean Sea and to link local differences in its properties to the driving processes. This emerging feature can help the marine ecosystem functioning to be better understood, also under the impacts of climate change.
Michael R. Stukel, Moira Décima, and Michael R. Landry
Biogeosciences, 19, 3595–3624, https://doi.org/10.5194/bg-19-3595-2022, https://doi.org/10.5194/bg-19-3595-2022, 2022
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The biological carbon pump (BCP) transports carbon into the deep ocean, leading to long-term marine carbon sequestration. It is driven by many physical, chemical, and ecological processes. We developed a model of the BCP constrained using data from 11 cruises in 4 different ocean regions. Our results show that sinking particles and vertical mixing are more important than transport mediated by vertically migrating zooplankton. They also highlight the uncertainty in current estimates of the BCP.
Ginevra Rosati, Donata Canu, Paolo Lazzari, and Cosimo Solidoro
Biogeosciences, 19, 3663–3682, https://doi.org/10.5194/bg-19-3663-2022, https://doi.org/10.5194/bg-19-3663-2022, 2022
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Methylmercury (MeHg) is produced and bioaccumulated in marine food webs, posing concerns for human exposure through seafood consumption. We modeled and analyzed the fate of MeHg in the lower food web of the Mediterranean Sea. The modeled spatial–temporal distribution of plankton bioaccumulation differs from the distribution of MeHg in surface water. We also show that MeHg exposure concentrations in temperate waters can be lowered by winter convection, which is declining due to climate change.
Yanda Ou, Bin Li, and Z. George Xue
Biogeosciences, 19, 3575–3593, https://doi.org/10.5194/bg-19-3575-2022, https://doi.org/10.5194/bg-19-3575-2022, 2022
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Over the past decades, the Louisiana–Texas shelf has been suffering recurring hypoxia (dissolved oxygen < 2 mg L−1). We developed a novel prediction model using state-of-the-art statistical techniques based on physical and biogeochemical data provided by a numerical model. The model can capture both the magnitude and onset of the annual hypoxia events. This study also demonstrates that it is possible to use a global model forecast to predict regional ocean water quality.
Eva Ehrnsten, Oleg Pavlovitch Savchuk, and Bo Gustav Gustafsson
Biogeosciences, 19, 3337–3367, https://doi.org/10.5194/bg-19-3337-2022, https://doi.org/10.5194/bg-19-3337-2022, 2022
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We studied the effects of benthic fauna, animals living on or in the seafloor, on the biogeochemical cycles of carbon, nitrogen and phosphorus using a model of the Baltic Sea ecosystem. By eating and excreting, the animals transform a large part of organic matter sinking to the seafloor into inorganic forms, which fuel plankton blooms. Simultaneously, when they move around (bioturbate), phosphorus is bound in the sediments. This reduces nitrogen-fixing plankton blooms and oxygen depletion.
Brandon J. McNabb and Philippe D. Tortell
Biogeosciences, 19, 1705–1721, https://doi.org/10.5194/bg-19-1705-2022, https://doi.org/10.5194/bg-19-1705-2022, 2022
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The trace gas dimethyl sulfide (DMS) plays an important role in the ocean sulfur cycle and can also influence Earth’s climate. Our study used two statistical methods to predict surface ocean concentrations and rates of sea–air exchange of DMS in the northeast subarctic Pacific. Our results show improved predictive power over previous approaches and suggest that nutrient availability, light-dependent processes, and physical mixing may be important controls on DMS in this region.
Krysten Rutherford, Katja Fennel, Dariia Atamanchuk, Douglas Wallace, and Helmuth Thomas
Biogeosciences, 18, 6271–6286, https://doi.org/10.5194/bg-18-6271-2021, https://doi.org/10.5194/bg-18-6271-2021, 2021
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Using a regional model of the northwestern North Atlantic shelves in combination with a surface water time series and repeat transect observations, we investigate surface CO2 variability on the Scotian Shelf. The study highlights a strong seasonal cycle in shelf-wide pCO2 and spatial variability throughout the summer months driven by physical events. The simulated net flux of CO2 on the Scotian Shelf is out of the ocean, deviating from the global air–sea CO2 flux trend in continental shelves.
Frerk Pöppelmeier, David J. Janssen, Samuel L. Jaccard, and Thomas F. Stocker
Biogeosciences, 18, 5447–5463, https://doi.org/10.5194/bg-18-5447-2021, https://doi.org/10.5194/bg-18-5447-2021, 2021
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Chromium (Cr) is a redox-sensitive element that holds promise as a tracer of ocean oxygenation and biological activity. We here implemented the oxidation states Cr(III) and Cr(VI) in the Bern3D model to investigate the processes that shape the global Cr distribution. We find a Cr ocean residence time of 5–8 kyr and that the benthic source dominates the tracer budget. Further, regional model–data mismatches suggest strong Cr removal in oxygen minimum zones and a spatially variable benthic source.
Felipe S. Freitas, Philip A. Pika, Sabine Kasten, Bo B. Jørgensen, Jens Rassmann, Christophe Rabouille, Shaun Thomas, Henrik Sass, Richard D. Pancost, and Sandra Arndt
Biogeosciences, 18, 4651–4679, https://doi.org/10.5194/bg-18-4651-2021, https://doi.org/10.5194/bg-18-4651-2021, 2021
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It remains challenging to fully understand what controls carbon burial in marine sediments globally. Thus, we use a model–data approach to identify patterns of organic matter reactivity at the seafloor across distinct environmental conditions. Our findings support the notion that organic matter reactivity is a dynamic ecosystem property and strongly influences biogeochemical cycling and exchange. Our results are essential to improve predictions of future changes in carbon cycling and climate.
Josué Bock, Martine Michou, Pierre Nabat, Manabu Abe, Jane P. Mulcahy, Dirk J. L. Olivié, Jörg Schwinger, Parvadha Suntharalingam, Jerry Tjiputra, Marco van Hulten, Michio Watanabe, Andrew Yool, and Roland Séférian
Biogeosciences, 18, 3823–3860, https://doi.org/10.5194/bg-18-3823-2021, https://doi.org/10.5194/bg-18-3823-2021, 2021
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In this study we analyse surface ocean dimethylsulfide (DMS) concentration and flux to the atmosphere from four CMIP6 Earth system models over the historical and ssp585 simulations.
Our analysis of contemporary (1980–2009) climatologies shows that models better reproduce observations in mid to high latitudes. The models disagree on the sign of the trend of the global DMS flux from 1980 onwards. The models agree on a positive trend of DMS over polar latitudes following sea-ice retreat dynamics.
Mariana Hill Cruz, Iris Kriest, Yonss Saranga José, Rainer Kiko, Helena Hauss, and Andreas Oschlies
Biogeosciences, 18, 2891–2916, https://doi.org/10.5194/bg-18-2891-2021, https://doi.org/10.5194/bg-18-2891-2021, 2021
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In this study we use a regional biogeochemical model of the eastern tropical South Pacific Ocean to implicitly simulate the effect that fluctuations in populations of small pelagic fish, such as anchovy and sardine, may have on the biogeochemistry of the northern Humboldt Current System. To do so, we vary the zooplankton mortality in the model, under the assumption that these fishes eat zooplankton. We also evaluate the model for the first time against mesozooplankton observations.
Roman Bezhenar, Kyeong Ok Kim, Vladimir Maderich, Govert de With, and Kyung Tae Jung
Biogeosciences, 18, 2591–2607, https://doi.org/10.5194/bg-18-2591-2021, https://doi.org/10.5194/bg-18-2591-2021, 2021
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A new approach to predicting the accumulation of radionuclides in fish was developed by taking into account heterogeneity of distribution of contamination in the organism and dependence of metabolic process rates on the fish mass. Predicted concentrations of radionuclides in fish agreed well with the laboratory and field measurements. The model with the defined generic parameters could be used in marine environments without local calibration, which is important for emergency decision support.
Emil De Borger, Justin Tiano, Ulrike Braeckman, Adriaan D. Rijnsdorp, and Karline Soetaert
Biogeosciences, 18, 2539–2557, https://doi.org/10.5194/bg-18-2539-2021, https://doi.org/10.5194/bg-18-2539-2021, 2021
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Bottom trawling alters benthic mineralization: the recycling of organic material (OM) to free nutrients. To better understand how this occurs, trawling events were added to a model of seafloor OM recycling. Results show that bottom trawling reduces OM and free nutrients in sediments through direct removal thereof and of fauna which transport OM to deeper sediment layers protected from fishing. Our results support temporospatial trawl restrictions to allow key sediment functions to recover.
Britta Munkes, Ulrike Löptien, and Heiner Dietze
Biogeosciences, 18, 2347–2378, https://doi.org/10.5194/bg-18-2347-2021, https://doi.org/10.5194/bg-18-2347-2021, 2021
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Cyanobacteria blooms can strongly aggravate eutrophication problems of water bodies. Their controls are, however, not comprehensively understood, which impedes effective management and protection plans. Here we review the current understanding of cyanobacteria blooms. Juxtaposition of respective field and laboratory studies with state-of-the-art mathematical models reveals substantial uncertainty associated with nutrient demands, grazing, and death of cyanobacteria.
Jens Terhaar, Olivier Torres, Timothée Bourgeois, and Lester Kwiatkowski
Biogeosciences, 18, 2221–2240, https://doi.org/10.5194/bg-18-2221-2021, https://doi.org/10.5194/bg-18-2221-2021, 2021
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The uptake of carbon, emitted as a result of human activities, results in ocean acidification. We analyse 21st-century projections of acidification in the Arctic Ocean, a region of particular vulnerability, using the latest generation of Earth system models. In this new generation of models there is a large decrease in the uncertainty associated with projections of Arctic Ocean acidification, with freshening playing a greater role in driving acidification than previously simulated.
Tobias R. Vonnahme, Martial Leroy, Silke Thoms, Dick van Oevelen, H. Rodger Harvey, Svein Kristiansen, Rolf Gradinger, Ulrike Dietrich, and Christoph Völker
Biogeosciences, 18, 1719–1747, https://doi.org/10.5194/bg-18-1719-2021, https://doi.org/10.5194/bg-18-1719-2021, 2021
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Diatoms are crucial for Arctic coastal spring blooms, and their growth is controlled by nutrients and light. At the end of the bloom, inorganic nitrogen or silicon can be limiting, but nitrogen can be regenerated by bacteria, extending the algal growth phase. Modeling these multi-nutrient dynamics and the role of bacteria is challenging yet crucial for accurate modeling. We recreated spring bloom dynamics in a cultivation experiment and developed a representative dynamic model.
Rebecca M. Wright, Corinne Le Quéré, Erik Buitenhuis, Sophie Pitois, and Mark J. Gibbons
Biogeosciences, 18, 1291–1320, https://doi.org/10.5194/bg-18-1291-2021, https://doi.org/10.5194/bg-18-1291-2021, 2021
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Jellyfish have been included in a global ocean biogeochemical model for the first time. The global mean jellyfish biomass in the model is within the observational range. Jellyfish are found to play an important role in the plankton ecosystem, influencing community structure, spatiotemporal dynamics and biomass. The model raises questions about the sensitivity of the zooplankton community to jellyfish mortality and the interactions between macrozooplankton and jellyfish.
Valeria Di Biagio, Gianpiero Cossarini, Stefano Salon, and Cosimo Solidoro
Biogeosciences, 17, 5967–5988, https://doi.org/10.5194/bg-17-5967-2020, https://doi.org/10.5194/bg-17-5967-2020, 2020
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Events that influence the functioning of the Earth’s ecosystems are of interest in relation to a changing climate. We propose a method to identify and characterise
wavesof extreme events affecting marine ecosystems for multi-week periods over wide areas. Our method can be applied to suitable ecosystem variables and has been used to describe different kinds of extreme event waves of phytoplankton chlorophyll in the Mediterranean Sea, by analysing the output from a high-resolution model.
Maria Paula da Silva, Lino A. Sander de Carvalho, Evlyn Novo, Daniel S. F. Jorge, and Claudio C. F. Barbosa
Biogeosciences, 17, 5355–5364, https://doi.org/10.5194/bg-17-5355-2020, https://doi.org/10.5194/bg-17-5355-2020, 2020
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In this study, we analyze the seasonal changes in the dissolved organic matter (DOM) quality (based on its optical properties) in four Amazon floodplain lakes. DOM plays a fundamental role in surface water chemistry, controlling metal bioavailability and mobility, and nutrient cycling. The model proposed in our paper highlights the potential to study DOM quality at a wider spatial scale, which may help to better understand the persistence and fate of DOM in the ecosystem.
Zhengchen Zang, Z. George Xue, Kehui Xu, Samuel J. Bentley, Qin Chen, Eurico J. D'Sa, Le Zhang, and Yanda Ou
Biogeosciences, 17, 5043–5055, https://doi.org/10.5194/bg-17-5043-2020, https://doi.org/10.5194/bg-17-5043-2020, 2020
Taylor A. Shropshire, Steven L. Morey, Eric P. Chassignet, Alexandra Bozec, Victoria J. Coles, Michael R. Landry, Rasmus Swalethorp, Glenn Zapfe, and Michael R. Stukel
Biogeosciences, 17, 3385–3407, https://doi.org/10.5194/bg-17-3385-2020, https://doi.org/10.5194/bg-17-3385-2020, 2020
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Zooplankton are the smallest animals in the ocean and important food for fish. Despite their importance, zooplankton have been relatively undersampled. To better understand the zooplankton community in the Gulf of Mexico (GoM), we developed a model to simulate their dynamics. We found that heterotrophic protists are important for supporting mesozooplankton, which are the primary prey of larval fish. The model developed in this study has the potential to improve fisheries management in the GoM.
Iris Kriest, Paul Kähler, Wolfgang Koeve, Karin Kvale, Volkmar Sauerland, and Andreas Oschlies
Biogeosciences, 17, 3057–3082, https://doi.org/10.5194/bg-17-3057-2020, https://doi.org/10.5194/bg-17-3057-2020, 2020
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Constants of global biogeochemical ocean models are often tuned
by handto match observations of nutrients or oxygen. We investigate the effect of this tuning by optimising six constants of a global biogeochemical model, simulated in five different offline circulations. Optimal values for three constants adjust to distinct features of the circulation applied and can afterwards be swapped among the circulations, without losing too much of the model's fit to observed quantities.
Laura Haffert, Matthias Haeckel, Henko de Stigter, and Felix Janssen
Biogeosciences, 17, 2767–2789, https://doi.org/10.5194/bg-17-2767-2020, https://doi.org/10.5194/bg-17-2767-2020, 2020
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Deep-sea mining for polymetallic nodules is expected to have severe environmental impacts. Through prognostic modelling, this study aims to provide a holistic assessment of the biogeochemical recovery after a disturbance event. It was found that the recovery strongly depends on the impact type; e.g. complete removal of the surface sediment reduces seafloor nutrient fluxes over centuries.
Fabian A. Gomez, Rik Wanninkhof, Leticia Barbero, Sang-Ki Lee, and Frank J. Hernandez Jr.
Biogeosciences, 17, 1685–1700, https://doi.org/10.5194/bg-17-1685-2020, https://doi.org/10.5194/bg-17-1685-2020, 2020
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We use a numerical model to infer annual changes of surface carbon chemistry in the Gulf of Mexico (GoM). The main seasonality drivers of partial pressure of carbon dioxide and aragonite saturation state from the model are temperature and river runoff. The GoM basin is a carbon sink in winter–spring and carbon source in summer–fall, but uptake prevails near the Mississippi Delta year-round due to high biological production. Our model results show good correspondence with observational studies.
Simon J. Parker
Biogeosciences, 17, 305–315, https://doi.org/10.5194/bg-17-305-2020, https://doi.org/10.5194/bg-17-305-2020, 2020
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Dissolved oxygen (DO) models typically assume constant ecosystem respiration over the course of a single day. Using a data-driven approach, this research examines this assumption in four streams across two (hydro-)geological types (Chalk and Greensand). Despite hydrogeological equivalence in terms of baseflow index for each hydrogeological pairing, model suitability differed within, rather than across, geology types. This corresponded with associated differences in timings of DO minima.
Fabrice Lacroix, Tatiana Ilyina, and Jens Hartmann
Biogeosciences, 17, 55–88, https://doi.org/10.5194/bg-17-55-2020, https://doi.org/10.5194/bg-17-55-2020, 2020
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Contributions of rivers to the oceanic cycling of carbon have been poorly represented in global models until now. Here, we assess the long–term implications of preindustrial riverine loads in the ocean in a novel framework which estimates the loads through a hierarchy of weathering and land–ocean export models. We investigate their impacts for the oceanic biological production and air–sea carbon flux. Finally, we assess the potential incorporation of the framework in an Earth system model.
Patrick A. Rafter, Aaron Bagnell, Dario Marconi, and Timothy DeVries
Biogeosciences, 16, 2617–2633, https://doi.org/10.5194/bg-16-2617-2019, https://doi.org/10.5194/bg-16-2617-2019, 2019
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The N isotopic composition of nitrate (
nitrate δ15N) is a useful tracer of ocean N cycling and many other ocean processes. Here, we use a global compilation of marine nitrate δ15N as an input, training, and validating dataset for an artificial neural network (a.k.a.,
machine learning) and examine basin-scale trends in marine nitrate δ15N from the surface to the seafloor.
Elena Terzić, Paolo Lazzari, Emanuele Organelli, Cosimo Solidoro, Stefano Salon, Fabrizio D'Ortenzio, and Pascal Conan
Biogeosciences, 16, 2527–2542, https://doi.org/10.5194/bg-16-2527-2019, https://doi.org/10.5194/bg-16-2527-2019, 2019
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Measuring ecosystem properties in the ocean is a hard business. Recent availability of data from Biogeochemical-Argo floats can help make this task easier. Numerical models can integrate these new data in a coherent picture and can be used to investigate the functioning of ecosystem processes. Our new approach merges experimental information and model capabilities to quantitatively demonstrate the importance of light and water vertical mixing for algae dynamics in the Mediterranean Sea.
Jens Terhaar, James C. Orr, Marion Gehlen, Christian Ethé, and Laurent Bopp
Biogeosciences, 16, 2343–2367, https://doi.org/10.5194/bg-16-2343-2019, https://doi.org/10.5194/bg-16-2343-2019, 2019
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A budget of anthropogenic carbon in the Arctic Ocean, the main driver of open-ocean acidification, was constructed for the first time using a high-resolution ocean model. The budget reveals that anthropogenic carbon enters the Arctic Ocean mainly by lateral transport; the air–sea flux plays a minor role. Coarser-resolution versions of the same model, typical of earth system models, store less anthropogenic carbon in the Arctic Ocean and thus underestimate ocean acidification in the Arctic Ocean.
Taylor S. Martin, François Primeau, and Karen L. Casciotti
Biogeosciences, 16, 347–367, https://doi.org/10.5194/bg-16-347-2019, https://doi.org/10.5194/bg-16-347-2019, 2019
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Nitrite is a key intermediate in many nitrogen (N) cycling processes in the ocean, particularly in areas with low oxygen that are hotspots for N loss. We have created a 3-D global N cycle model with nitrite as a tracer. Stable isotopes of N are also included in the model and we are able to model the isotope fractionation associated with each N cycling process. Our model accurately represents N concentrations and isotope distributions in the ocean.
Camille Richon, Jean-Claude Dutay, Laurent Bopp, Briac Le Vu, James C. Orr, Samuel Somot, and François Dulac
Biogeosciences, 16, 135–165, https://doi.org/10.5194/bg-16-135-2019, https://doi.org/10.5194/bg-16-135-2019, 2019
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We evaluate the effects of climate change and biogeochemical forcing evolution on the nutrient and plankton cycles of the Mediterranean Sea for the first time. We use a high-resolution coupled physical and biogeochemical model and perform 120-year transient simulations. The results indicate that changes in external nutrient fluxes and climate change may have synergistic or antagonistic effects on nutrient concentrations, depending on the region and the scenario.
Angela M. Kuhn, Katja Fennel, and Ilana Berman-Frank
Biogeosciences, 15, 7379–7401, https://doi.org/10.5194/bg-15-7379-2018, https://doi.org/10.5194/bg-15-7379-2018, 2018
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Recent studies demonstrate that marine N2 fixation can be carried out without light. However, direct measurements of N2 fixation in dark environments are relatively scarce. This study uses a model that represents biogeochemical cycles at a deep-ocean location in the Gulf of Aqaba (Red Sea). Different model versions are used to test assumptions about N2 fixers. Relaxing light limitation for marine N2 fixers improved the similarity between model results and observations of deep nitrate and oxygen.
Prima Anugerahanti, Shovonlal Roy, and Keith Haines
Biogeosciences, 15, 6685–6711, https://doi.org/10.5194/bg-15-6685-2018, https://doi.org/10.5194/bg-15-6685-2018, 2018
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Minor changes in the biogeochemical model equations lead to major dynamical changes. We assessed this structural sensitivity for the MEDUSA biogeochemical model on chlorophyll and nitrogen concentrations at five oceanographic stations over 10 years, using 1-D ensembles generated by combining different process equations. The ensemble performed better than the default model in most of the stations, suggesting that our approach is useful for generating a probabilistic biogeochemical ensemble model.
Audrey Gimenez, Melika Baklouti, Thibaut Wagener, and Thierry Moutin
Biogeosciences, 15, 6573–6589, https://doi.org/10.5194/bg-15-6573-2018, https://doi.org/10.5194/bg-15-6573-2018, 2018
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During the OUTPACE cruise conducted in the oligotrophic to ultra-oligotrophic region of the western tropical South Pacific, two contrasted regions were sampled in terms of N2 fixation rates, primary production rates and nutrient availability. The aim of this work was to investigate the role of N2 fixation in the differences observed between the two contrasted areas by comparing two simulations only differing by the presence or not of N2 fixers using a 1-D biogeochemical–physical coupled model.
Jenny Hieronymus, Kari Eilola, Magnus Hieronymus, H. E. Markus Meier, Sofia Saraiva, and Bengt Karlson
Biogeosciences, 15, 5113–5129, https://doi.org/10.5194/bg-15-5113-2018, https://doi.org/10.5194/bg-15-5113-2018, 2018
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This paper investigates how phytoplankton concentrations in the Baltic Sea co-vary with nutrient concentrations and other key variables on inter-annual timescales in a model integration over the years 1850–2008. The study area is not only affected by climate change; it has also been subjected to greatly increased nutrient loads due to extensive use of agricultural fertilizers. The results indicate the largest inter-annual coherence of phytoplankton with the limiting nutrient.
Cyril Dutheil, Olivier Aumont, Thomas Gorguès, Anne Lorrain, Sophie Bonnet, Martine Rodier, Cécile Dupouy, Takuhei Shiozaki, and Christophe Menkes
Biogeosciences, 15, 4333–4352, https://doi.org/10.5194/bg-15-4333-2018, https://doi.org/10.5194/bg-15-4333-2018, 2018
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N2 fixation is recognized as one of the major sources of nitrogen in the ocean. Thus, N2 fixation sustains a significant part of the primary production (PP) by supplying the most common limiting nutrient for phytoplankton growth. From numerical simulations, the local maximums of Trichodesmium biomass in the Pacific are found around islands, explained by the iron fluxes from island sediments. We assessed that 15 % of the PP may be due to Trichodesmium in the low-nutrient, low-chlorophyll areas.
Cited articles
Arndt, S., Regnier, P., and Vanderborght, J. P.: Seasonally-resolved nutrient
export fluxes and filtering capacities in a macrotidal estuary, J. Marine
Syst., 78, 42–58, https://doi.org/10.1016/j.jmarsys.2009.02.008, 2009.
Arndt, S., Lacroix, G., Gypens, N., Regnier, P., and Lancelot, C.: Nutrient
dynamics and phytoplankton development along an estuary–coastal zone
continuum: A model study, J. Marine Syst., 84, 49–66,
https://doi.org/10.1016/j.jmarsys.2010.08.005, 2011.
Baker, A.: Land Use and Water Quality, in: Encyclopedia of Hydrological Sciences, edited by: Anderson, M. G. and McDonnell, J. J., https://doi.org/10.1002/0470848944.hsa195, 2006.
Barbier, E. B., Hacker, S. D., Kennedy, C., Koch, E. W., Stier, A. C., and
Silliman, B. R.: The value of estuarine and coastal ecosystem services,
Ecol. Monogr., 81, 169–193, https://doi.org/10.1890/10-1510.1, 2011.
Bauer, J. E., Cai, W. J., Raymond, P. A., Bianchi, T. S., Hopkinson, C. S., and Regnier, P. A.: The
changing carbon cycle of the coastal ocean, Nature,
504, 61–70, https://doi.org/10.1038/nature12857, 2013.
Bernot, M. J. and Dodds, W. K.: Nitrogen Retention, Removal, and Saturation
in Lotic Ecosystems, Ecosystems, 8, 442–453,
https://doi.org/10.1007/s10021-003-0143-y, 2005.
Billen, G. and Garnier, J.: The Phison River plume: Coastal eutrophication
in response to changes in land use and water management in the watershed,
Aquat. Microb. Ecol., 13, 3–17, https://doi.org/10.3354/ame013003, 1997.
Billen, G. and Garnier, J.: River basin nutrient delivery to the coastal
sea: Assessing its potential to sustain new production of non-siliceous
algae, Mar. Chem., 106, 148–160,
https://doi.org/10.1016/j.marchem.2006.12.017, 2007.
Billen, G., Garnier, J., and Silvestre, M.: A simplified algorithm for
calculating benthic nutrient fluxes in river systems, Ann. Limnol., 51,
37–47, https://doi.org/10.1051/limn/2014030, 2015.
Billy, C., Birgand, F., Ansart, P., Peschard, J., Sebilo, M., and Tournebize,
J.: Factors controlling nitrate concentrations in surface waters of an
artificially drained agricultural watershed, Landscape Ecol., 28, 665–684,
https://doi.org/10.1007/s10980-013-9872-2, 2013.
Brion, N., Billen, G., Guezennec, L., and Ficht, A.: Distribution of
nitrifying activity in the Seine River “France” from Paris to the estuary,
Estuaries, 23, 669–682, https://doi.org/10.2307/1352893, 2000.
Brzezinski, M. A.: THE Si : C : N RATIO OF MARINE DIATOMS: INTERSPECIFIC
VARIABILITY AND THE EFFECT OF SOME ENVIRONMENTAL VARIABLES, J. Phycol.,
21, 347–357, https://doi.org/10.1111/j.0022-3646.1985.00347.x, 1985.
Burchard, H., Schuttelaars, H. M., and Ralston, D. K.: Sediment trapping in estuaries, Annu. Rev. Mar. Sci., 10, 371–395, https://doi.org/10.1146/annurev-marine-010816-060535, 2018.
CORINE Land Cover: L'occupation des sols en 2018, available at:
https://land.copernicus.eu/pan-european/corine-land-cover/clc2018 (last access: 7 February 2022),
2018.
Coynel, A., Seyler, P., Etcheber, H., and Meybeck, M.: Spatial and seasonal
dynamics of total suspended sediment and organic carbon species in the Congo
River, Global Biogeochem. Cy., 19, 1–17, https://doi.org/10.1029/2004GB002335, 2005.
Coynel, A., Gorse, L., Curti, C., Schafer, J., Grosbois, C., Morelli, G.,
Ducassou, E., Blanc, G., Maillet, G. M., and Mojtahid, M.: Spatial
distribution of trace elements in the surface sediments of a major European
estuary (Loire Estuary, France): Source identification and evaluation of
anthropogenic contribution, J. Sea Res., 118, 77–91,
https://doi.org/10.1016/j.seares.2016.08.005, 2016.
Crossland, C. J., Kremer, H. H., Lindeboom, H. J., Marshal Crosslandl, J. I.,
and Le Tissier, M. D. A. (Eds.): Coastal Fluxes in the Anthropocene, Springer Berlin Heidelberg, Berlin, Heidelberg, https://doi.org/10.1007/3-540-27851-6, 2005.
Cugier, P., Billen, G., Guillaud, J. F., Garnier, J., and Ménesguen, A.:
Modelling the eutrophication of the Seine Bight (France) under historical,
present and future riverine nutrient loading, J. Hydrol., 304,
381–396, https://doi.org/10.1016/j.jhydrol.2004.07.049, 2005a.
Cugier, P., Ménesguen, A., and Guillaud, J. F.: Three-dimensional (3D)
ecological modelling of the Bay of Seine (English Channel, France), J. Sea
Res., 54, 104–124, https://doi.org/10.1016/j.seares.2005.02.009, 2005b.
Defontaine, S., Sous, D., Morichon, D., Verney, R., and Monperrus, M.:
Hydrodynamics and SPM transport in an engineered tidal estuary: The Adour
river (France), Estuar. Coast. Shelf S., 231, 106445,
https://doi.org/10.1016/j.ecss.2019.106445, 2019.
Dürr, H. H., Laruelle, G. G., van Kempen, C. M., Slomp, C. P., Meybeck,
M., and Middelkoop, H.: Worldwide Typology of Nearshore Coastal Systems:
Defining the Estuarine Filter of River Inputs to the Oceans, Estuar.
Coast., 34, 441–458, https://doi.org/10.1007/s12237-011-9381-y, 2011.
Edmondson, W. T.: VOLLENWEIDER, R. A. 1968. Water management research. Scientific fundamentals of the eutrophication of lakes and flowing waters with particular reference to nitrogen and phosphorus as factors in eutrophication. Organization for Economic Co-operation and Development. Directorate for Scientific Affairs. Paris. Mimeographed. 159 p. + 34 Figs. + 2 separately paged annexes: Bibliography, 61 p; Current status of research on eutrophication in Europe, the United States and Canada, 20 p. (French and German versions available.), Limnol. Oceanogr., 15, 169–170, https://doi.org/10.4319/lo.1970.15.1.0169, 1970.
Escolano, J. J., Pedreño, J. N., Lucas, I. G., Almendro Candel, M. B.,
and Zorpas, A. A.: Decreased Organic Carbon Associated With Land Management
in Mediterranean Environments, Report From the Commission to the European
Parliament, the Council, Elsevier Inc., 2018.
Etcheber, H., Taillez, A., Abril, G., Garnier, J., Servais, P., Moatar, F.,
and Commarieu, M. V.: Particulate organic carbon in the estuarine turbidity
maxima of the Gironde, Loire and Seine estuaries: Origin and lability,
Hydrobiologia, 588, 245–259, https://doi.org/10.1007/s10750-007-0667-9, 2007.
EU Water Framework Directive (WFD): DIRECTIVE 2000/60/EC OF THE EUROPEAN
PARLIAMENT AND OF THE COUNCIL, available at:
https://ec.europa.eu/environment/water/water-framework/index_en.html (last access: 7 February 2022), 2000.
Garnier, J., Billen, G., and Cébron, A.: Modelling nitrogen
transformations in the lower Seine river and estuary (France): impact of
wastewater release on oxygenation and N2O emission, Hydrobiologia, 588,
291–302, https://doi.org/10.1007/s10750-007-0670-1, 2007.
Garnier, J., Billen, G., Even, S., Etcheber, H., and Servais, P.: Organic
matter dynamics and budgets in the turbidity maximum zone of the Seine
Estuary (France), Estuar. Coast. Shelf S., 77, 150–162,
https://doi.org/10.1016/j.ecss.2007.09.019, 2008.
Garnier, J., Beusen, A., Thieu, V., Billen, G., and Bouwman, L.: N : P : Si
nutrient export ratios and ecological consequences in coastal seas evaluated
by the ICEP approach, Global Biogeochem. Cy., 24, GB0A05,
https://doi.org/10.1029/2009GB003583, 2010a.
Garnier, J., Billen, G., Némery, J., and Sebilo, M.: Transformations of
nutrients (N, P, Si) in the turbidity maximum zone of the Seine estuary and
export to the sea, Estuar. Coast. Shelf S., 90, 129–141,
https://doi.org/10.1016/j.ecss.2010.07.012, 2010b.
Garnier, J., Riou, P., Le Gendre, R., Ramarson, A., Billen, G., Cugier, P.,
Schapira, M., Théry, S., Thieu, V., and Ménesguen, A.: Managing the
Agri-Food System of Watersheds to Combat Coastal Eutrophication: A
Land-to-Sea Modelling Approach to the French Coastal English Channel,
Geosciences, 9, 441, https://doi.org/10.3390/geosciences9100441, 2019.
Garnier, J., Billen, G., Lassaletta, L., Vigiak, O., Nikolaidis, N. P., and
Grizzetti, B.: Hydromorphology of coastal zone and structure of watershed
agro-food system are main determinants of coastal eutrophication, Environ.
Res. Lett., 16, 023005, https://doi.org/10.1088/1748-9326/abc777, 2021.
Glibert, P. M.: Harmful algae at the complex nexus of eutrophication and
climate change, Harmful Algae, 91, 101583,
https://doi.org/10.1016/j.hal.2019.03.001, 2020.
Gohin, F., Van der Zande, D., Tilstone, G., Eleveld, M. A., Lefebvre, A.,
Andrieux-Loyer, F., Blauw, A. N., Bryère, P., Devreker, D., Garnesson,
P., Hernández Fariñas, T., Lamaury, Y., Lampert, L., Lavigne, H.,
Menet-Nedelec, F., Pardo, S., and Saulquin, B.: Twenty years of satellite and
in situ observations of surface chlorophyll-a from the northern Bay of
Biscay to the eastern English Channel. Is the water quality improving?,
Remote Sens. Environ., 233, 111343,
https://doi.org/10.1016/j.rse.2019.111343, 2019.
Goubert, E., Menier, D., Traini, C., Mathew, M. J., and Le Gall, R.:Recent Morphobathymetrical Changes of the Vilaine Estuary (South Brittany, France): Discrimination of Natural and Anthropogenic Forcings and Assessment for Future Trends, Elsevier, Coastal Zone Management, 485–500, ISBN 978-0-12-814350, 2019.
Guillaud, J.-F., Aminot, A., Delmas, D., Gohin, F., Lunven, M., Labry, C.,
and Herbland, A.: Seasonal variation of riverine nutrient inputs in the
northern Bay of Biscay (France), and patterns of marine phytoplankton
response, J. Marine Syst., 72, 309–319,
https://doi.org/10.1016/j.jmarsys.2007.03.010, 2008.
Hofmann, A. F., Soetaert, K., and Middelburg, J. J.: Present nitrogen and carbon dynamics in the Scheldt estuary using a novel 1-D model, Biogeosciences, 5, 981–1006, https://doi.org/10.5194/bg-5-981-2008, 2008.
Howarth, R., Chan, F., Conley, D. J, Garnier, J., Doney, S. C., Marino, R., and Billen, G.: Coupled Biogeochemical Cycles: Eutrophication and Hypoxia in Temperate Estuaries and Coastal Marine Ecosystems, Front. Ecol. Environ., 9, 18–26, https://doi.org/10.1890/100008, 2011.
Howarth, R. W., Fruci, J. R., and Sherman, D.: Inputs of Sediment and Carbon
to an Estuarine Ecosystem: Influence of Land Use, Ecol. Appl., 1, 27–39,
https://doi.org/10.2307/1941845, 1991.
Hu, J. and Li, S.: Modeling the mass fluxes and transformations of nutrients
in the Pearl River Delta, China, J. Marine Syst., 78, 146–167,
https://doi.org/10.1016/j.jmarsys.2009.05.001, 2009.
Husson, B., Hernández-Fariñas, T., Le Gendre, R., Schapira, M., and
Chapelle, A.: Two decades of Pseudo-nitzschia spp. blooms and king scallop
(Pecten maximus) contamination by domoic acid along the French Atlantic and
English Channel coasts: Seasonal dynamics, spatial heterogeneity and
interannual variability, Harmful Algae, 51, 26–39,
https://doi.org/10.1016/j.hal.2015.10.017, 2016.
INSEE: Populations légales 2014, available at:
https://www.insee.fr/fr/statistiques/2525755?sommaire=2525768#consulter-sommaire (last access: 7 February 2022),
2014.
Jakobsen, H. H. and Markager, S.: Carbon-to-chlorophyll ratio for
phytoplankton in temperate coastal waters: Seasonal patterns and
relationship to nutrients, Limnol. Oceanogr., 61, 1853–1868,
https://doi.org/10.1002/lno.10338, 2016.
Jay, D. A., Uncles, R. J., Largier, J., Geyer, W. R., Vallino, J., and
Boynton, W. R.: A Review of Recent Developments in Estuarine Scalar Flux
Estimation, Estuaries, 20, 262, https://doi.org/10.2307/1352342, 1997.
Kaiser, D., Unger, D., Qiu, G., Zhou, H., and Gan, H.: Natural and human
influences on nutrient transport through a small subtropical Chinese
estuary, Sci. Total Environ., 450–451, 92–107,
https://doi.org/10.1016/j.scitotenv.2013.01.096, 2013.
Kobori, H. and Taga, N.: Phosphatase activity and its rôle in the mineralization of organic phosphorus in coastal sea water, J. Exp. Mar. Bio. Ecol., 36, 23–39, https://doi.org/10.1016/0022-0981(79)90098-4, 1979.
Labry, C., Delmas, D., Youenou, A., Quere, J., Leynaert, A., Fraisse, S., Raimonet, M., and Ragueneau, O.: High alkaline phosphatase activity in phosphate replete waters: The case of two macrotidal estuaries, Limnol. Oceanogr., 61, 1513–1529, https://doi.org/10.1002/lno.10315, 2016.
Lajaunie-Salla, K., Wild-Allen, K., Sottolichio, A., Thouvenin, B., Litrico,
X., and Abril, G.: Impact of urban effluents on summer hypoxia in the highly
turbid Gironde Estuary, applying a 3D model coupling hydrodynamics, sediment
transport and biogeochemical processes, J. Marine Syst., 174, 89–105,
https://doi.org/10.1016/j.jmarsys.2017.05.009, 2017.
Lamy, D., Artigas, L. F., Jauzein, C., Lizon, F., and Cornille, V.: Coastal
bacterial viability and production in the eastern English Channel: A case
study during a Phaeocystis globosa bloom, J. Sea Res., 56, 227–238,
https://doi.org/10.1016/j.seares.2006.04.003, 2006.
Laruelle, G. G., Goossens, N., Arndt, S., Cai, W.-J., and Regnier, P.: Air–water CO2 evasion from US East Coast estuaries, Biogeosciences, 14, 2441–2468, https://doi.org/10.5194/bg-14-2441-2017, 2017.
Laruelle, G. G., Marescaux, A., Gendre, R. Le, Garnier, J., Rabouille, C.,
Thieu, V., and Lehrter, J. C.: Carbon Dynamics Along the Seine River
Network: Insight From a Coupled Estuarine/River Modeling Approach,
6, 1–16, https://doi.org/10.3389/fmars.2019.00216, 2019.
Lazure, P. and Dumas, F.: An external–internal mode coupling for a 3D
hydrodynamical model for applications at regional scale (MARS), Adv. Water
Resour., 31, 233–250, https://doi.org/10.1016/j.advwatres.2007.06.010, 2008.
Lefebvre, A., Guiselin, N., Barbet, F., and Artigas, F. L.: Long-term
hydrological and phytoplankton monitoring (1992–2007) of three potentially
eutrophic systems in the eastern English Channel and the Southern Bight of
the North Sea, ICES J. Mar. Sci., 68, 2029–2043,
https://doi.org/10.1093/icesjms/fsr149, 2011.
Liquete, C., Piroddi, C., Drakou, E. G., Gurney, L., Katsanevakis, S.,
Charef, A., and Egoh, B.: Current Status and Future Prospects for the
Assessment of Marine and Coastal Ecosystem Services: A Systematic Review,
edited by S. J. Bograd, PLoS One, 8, e67737,
https://doi.org/10.1371/journal.pone.0067737, 2013.
Lockhart, K. M., King, A. M., and Harter, T.: Identifying sources of
groundwater nitrate contamination in a large alluvial groundwater basin with
highly diversified intensive agricultural production, J. Contam. Hydrol.,
151, 140–154, https://doi.org/10.1016/j.jconhyd.2013.05.008, 2013.
Luu, T. N. M., Garnier, J., Billen, G., Le, T. P. Q., Nemery, J., Orange, D.,
and Le, L. A.: N, P, Si budgets for the Red River Delta (northern Vietnam):
How the delta affects river nutrient delivery to the sea, Biogeochemistry,
107, 241–259, https://doi.org/10.1007/s10533-010-9549-8, 2012.
McLean, M. J., Mouillot, D., Goascoz, N., Schlaich, I., and Auber, A.:
Functional reorganization of marine fish nurseries under climate warming,
Glob. Change Biol., 25, 660–674, https://doi.org/10.1111/gcb.14501, 2019.
Ménesguen, A., Dussauze, M., and Dumas, F.: Designing optimal scenarios
of nutrient loading reduction in a WFD/MSFD perspective by using passive
tracers in a biogeochemical-3D model of the English Channel/Bay of Biscay
area, Ocean Coast. Manage., 163, 37–53,
https://doi.org/10.1016/j.ocecoaman.2018.06.005, 2018a.
Ménesguen, A., Desmit, X., Dulière, V., Lacroix, G., Thouvenin, B.,
Thieu, V., and Dussauze, M.: How to avoid eutrophication in coastal seas? A
new approach to derive river-specific combined nitrate and phosphate maximum
concentrations, Sci. Total Environ., 628–629, 400–414,
https://doi.org/10.1016/j.scitotenv.2018.02.025, 2018b.
Ménesguen, A., Dussauze, M., Dumas, F., Thouvenin, B., Garnier, V.,
Lecornu, F., and Répécaud, M.: Ecological model of the Bay of Biscay
and English Channel shelf for environmental status assessment part 1:
Nutrients, phytoplankton and oxygen, Ocean Model., 133,
56–78, https://doi.org/10.1016/j.ocemod.2018.11.002, 2019.
Michel, P., Boutier, B., and Chiffoleau, J. F.: Net fluxes of dissolved
arsenic, cadmium, copper, zinc, nitrogen and phosphorus from the Gironde
Estuary (France): Seasonal variations and trends, Estuar. Coast. Shelf S.,
51, 451–462, https://doi.org/10.1006/ecss.2000.0691, 2000.
Middelburg, J. J. and Herman, P. M. J.: Organic matter processing in tidal
estuaries, Mar. Chem., 106, 127–147,
https://doi.org/10.1016/j.marchem.2006.02.007, 2007.
Modéran, J., David, V., Bouvais, P., Richard, P., and Fichet, D.: Organic
matter exploitation in a highly turbid environment: Planktonic food web in
the Charente estuary, France, Estuar. Coast. Shelf S., 98, 126–137,
https://doi.org/10.1016/j.ecss.2011.12.018, 2012.
Moriasi, D. N., Arnold, J. G., Van Liew, M. W., Bingner, R. L., Harmel, R.
D., and Veith, T. L.: Model Evaluation Guidelines for Systematic
Quantification of Accuracy in Watershed Simulations, T. ASABE, 50,
885–900, https://doi.org/10.13031/2013.23153, 2007.
Nguyen, A. T., Némery, J., Gratiot, N., Garnier, J., Dao, T. S., Thieu,
V., and Laruelle, G. G.: Biogeochemical functioning of an urbanized tropical
estuary: Implementing the generic C-GEM (reactive transport) model, Sci.
Total Environ., 784, 147261, https://doi.org/10.1016/j.scitotenv.2021.147261, 2021.
Nguyen, T. T. N., Némery, J., Gratiot, N., Garnier, J., Strady, E.,
Tran, V. Q., Nguyen, A. T., Nguyen, T. N. T., Golliet, C., and Aimé, J.:
Phosphorus adsorption/desorption processes in the tropical Saigon River
estuary (Southern Vietnam) impacted by a megacity, Estuar. Coast. Shelf
S., 227, 106321, https://doi.org/10.1016/j.ecss.2019.106321, 2019.
Nixon, S. W., Ammerman, J. W., Atkinson, L. P., Berounsky, V. M., Billen,
G., Boicourt, W. C., Boynton, W. R., Church, T. M., Ditoro, D. M., Elmgren,
R., Garber, J. H., Giblin, A. E., Jahnke, R. A., Owens, N. J. P., Pilson, M.
E. Q., and Seitzinger, S. P.: The fate of nitrogen and phosphorus at the
land-sea margin of the North Atlantic Ocean, Biogeochemistry, 35,
141–180, https://doi.org/10.1007/BF02179826, 1996.
Normandin, C., Lubac, B., Sottolichio, A., Frappart, F., Ygorra, B., and
Marieu, V.: Analysis of Suspended Sediment Variability in a Large Highly
Turbid Estuary Using a 5-Year-Long Remotely Sensed Data Archive at High
Resolution, J. Geophys. Res.-Ocean, 124, 7661–7682,
https://doi.org/10.1029/2019JC015417, 2019.
Perez, B. C., Day, J. W., Justic, D., Lane, R. R., and Twilley, R. R.:
Nutrient stoichiometry, freshwater residence time, and nutrient retention in
a river-dominated estuary in the Mississippi delta, Hydrobiologia, 658,
41–54, https://doi.org/10.1007/s10750-010-0472-8, 2011.
Pozdnyakov, D. V, Pettersson, L. H., and Korosov, A. A.: Exploring the Marine
Ecology from Space, Springer International Publishing, Cham., ISBN 978-3-3193-007-57, 2017.
Pritchard, D. W.: What is an estuary: physical viewpoint, in: Estuaries,
AAAS, Washington DC, 3–5, Pub. 83, 1967.
Ragueneau, O., Chauvaud, L., Leynaert, A., Thouzeau, G., Paulet, Y.-M., Bonnet, S., Lorrain, A., Grall, J., Corvaisier, R., Le Hir, M., Jean, F., and Clavier, J.: Direct evidence of a biologically active coastal silicate pump: ecological implications, Limnol. Oceanogr., 47, 1849–1854, 2002.
Ratmaya, W., Soudant, D., Salmon-Monviola, J., Plus, M., Cochennec-Laureau, N., Goubert, E., Andrieux-Loyer, F., Barillé, L., and Souchu, P.: Reduced phosphorus loads from the Loire and Vilaine rivers were accompanied by increasing eutrophication in the Vilaine Bay (south Brittany, France), Biogeosciences, 16, 1361–1380, https://doi.org/10.5194/bg-16-1361-2019, 2019.
Redfield, A. C., Ketchum, B. H., and Richards, F. A.: The Influence of
Organisms on the Composition of the Sea Water, in: The Sea,
edited by: Hill, M. N., Vol. 2, Interscience Publishers, New York, 26–77,
1963.
Regnier, P., Mouchet, A., Wollast, R., and Ronday, F.: A discussion of
methods for estimating residual fluxes in strong tidal estuaries, Cont.
Shelf Res., 18, 1543–1571, https://doi.org/10.1016/S0278-4343(98)00071-5, 1998.
Regnier, P., Arndt, S., Goossens, N., Volta, C., Laruelle, G. G., Lauerwald,
R., and Hartmann, J.: Modelling Estuarine Biogeochemical Dynamics: From the
Local to the Global Scale, Aquat. Geochem., 19, 591–626,
https://doi.org/10.1007/s10498-013-9218-3, 2013.
REPHY: French Observation and Monitoring program for Phytoplankton and
Hydrology in coastal waters. Metropolitan data, SEANOE [data set],
https://doi.org/10.17882/47248, 2021.
Roubeix, V., Rousseau, V., and Lancelot, C.: Diatom succession and silicon removal from freshwater in estuarine mixing zones: From experiment to modelling, Estuar. Coast. Shelf S., 78, 14–26, https://doi.org/10.1016/j.ecss.2007.11.007, 2008.
Romero, E., Garnier, J., Lassaletta, L., Billen, G., Le Gendre, R., Riou, P.,
and Cugier, P.: Large-scale patterns of river inputs in southwestern Europe:
Seasonal and interannual variations and potential eutrophication effects at
the coastal zone, Biogeochemistry, 113, 481–505,
https://doi.org/10.1007/s10533-012-9778-0, 2013.
Romero, E., Le Gendre, R., Garnier, J., Billen, G., Fisson, C., Silvestre,
M., and Riou, P.: Long-term water quality in the lower Seine: Lessons learned
over 4 decades of monitoring, Environ. Sci. Policy, 58, 141–154,
https://doi.org/10.1016/j.envsci.2016.01.016, 2016.
Romero, E., Garnier, J., Billen, G., Ramarson, A., Riou, P., and Le Gendre,
R.: Modeling the biogeochemical functioning of the Seine estuary and its
coastal zone: Export, retention, and transformations, Limnol. Oceanogr.,
64, 895–912, https://doi.org/10.1002/lno.11082, 2019.
Savenije, H. H. G.: Salinity and tides in alluvial estuaries,
available at:
http://hubertsavenije.files.wordpress.com/2014/01/salinityandtides2_21.pdf (last access: 20 September 2020), 2012.
Savoye, N., David, V., Morisseau, F., Etcheber, H., Abril, G., Billy, I.,
Charlier, K., Oggian, G., Derriennic, H., and Sautour, B.: Origin and
composition of particulate organic matter in a macrotidal turbid estuary:
The Gironde Estuary, France, Estuar. Coast. Shelf S., 108, 16–28,
https://doi.org/10.1016/j.ecss.2011.12.005, 2012.
Sebilo, M., Billen, G., Mayer, B., Billiou, D., Grably, M., Garnier, J., and
Mariotti, A.: Assessing nitrification and denitrification in the seine river
and estuary using chemical and isotopic techniques, Ecosystems, 9,
564–577, https://doi.org/10.1007/s10021-006-0151-9, 2006.
Seitzinger, S. P.: Denitrification in freshwater and coastal marine
ecosystems: Ecological and geochemical significance, Limnol. Oceanogr.,
33, 702–724, https://doi.org/10.4319/lo.1988.33.4part2.0702, 1988.
Soetaert, K., Middelburg, J. J., Herman, P. M. J., and Buis, K.: On the coupling
of benthic and pelagic biogeochemical models, Earth-Sci. Rev.,
51, 173–201, https://doi.org/10.1016/S0012-8252(00)00004-0, 2000.
Soletchnik, P., Ropert, M., Mazurié, J., Gildas Fleury, P., and Le Coz,
F.: Relationships between oyster mortality patterns and environmental data
from monitoring databases along the coasts of France, Aquaculture,
271, 384–400, https://doi.org/10.1016/j.aquaculture.2007.02.049, 2007.
Thouvenin, B., Gonzalez, J., and Boutier, B.: Modelling of pollutant
behaviour in estuaries: Application to cadmium in the Loire estuary, Mar.
Chem., 58, 147–161, https://doi.org/10.1016/S0304-4203(97)00031-5, 1997.
Toublanc, F., Brenon, I., Coulombier, T., and Le Moine, O.: Fortnightly tidal
asymmetry inversions and perspectives on sediment dynamics in a macrotidal
estuary (Charente, France), Cont. Shelf Res., 94, 42–54,
https://doi.org/10.1016/j.csr.2014.12.009, 2015.
Urban Wastewater Treatment Directive: UWWTD (Urban wastewater treatment
Directive) (1991) 91/271/CEE du Conseil, du 21 mai 1991, relative au
traitement des eaux urbaines résiduaires, https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=celex:31991L0271 (last access: 7 February 2022) 1991.
Vanderborght, J. P., Folmer, I. M., Aguilera, D. R., Uhrenholdt, T., and
Regnier, P.: Reactive-transport modelling of C, N, and O2 in a
river-estuarine-coastal zone system: Application to the Scheldt estuary,
Mar. Chem., 106, 92–110, https://doi.org/10.1016/j.marchem.2006.06.006,
2007.
Verri, G., Mahmoudi Kurdistani, S., Coppini, G., and Valentini, A.: Recent
Advances of a Box Model to Represent the Estuarine Dynamics: Time-Variable
Estuary Length and Eddy Diffusivity, J. Adv. Model. Earth Sy., 13,
1–16, https://doi.org/10.1029/2020MS002276, 2021.
Vilas, F., Rubio, B., Rey, D., and Bernabeu, A. M.: Estuary, in: Encyclopedia
of Planetary Landforms, 1–7, Springer, New York, NY, https://doi.org/10.1007/978-1-4614-3134-3, 2021.
Volta, C., Arndt, S., Savenije, H. H. G., Laruelle, G. G., and Regnier, P.: C-GEM (v 1.0): a new, cost-efficient biogeochemical model for estuaries and its application to a funnel-shaped system, Geosci. Model Dev., 7, 1271–1295, https://doi.org/10.5194/gmd-7-1271-2014, 2014.
Volta, C., Laruelle, G. G., Arndt, S., and Regnier, P.: Linking biogeochemistry to hydro-geometrical variability in tidal estuaries: a generic modeling approach, Hydrol. Earth Syst. Sci., 20, 991–1030, https://doi.org/10.5194/hess-20-991-2016, 2016a.
Volta, C., Laruelle, G. G., and Regnier, P.: Regional carbon and CO2 budgets
of North Sea tidal estuaries, Estuar. Coast. Shelf S., 176, 76–90,
https://doi.org/10.1016/j.ecss.2016.04.007, 2016b.
Wild-Allen, K., Skerratt, J., Whitehead, J., Rizwi, F., and Parslow, J.:
Mechanisms driving estuarine water quality: A 3D biogeochemical model
forinformed management, Estuar. Coast. Shelf S., 135, 33–45,
https://doi.org/10.1016/j.ecss.2013.04.009, 2013.
Short summary
Estuaries are key reactive ecosystems along the land–ocean aquatic continuum and are often strongly impacted by anthropogenic activities. We calculated nutrient in and out fluxes by using a 1-D transient model for seven estuaries along the French Atlantic coast. Among these, large estuaries with high residence times showed higher retention rates than medium and small ones. All reveal coastal eutrophication due to the excess of diffused nitrogen from intensive agricultural river basins.
Estuaries are key reactive ecosystems along the land–ocean aquatic continuum and are often...
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