Articles | Volume 22, issue 10
https://doi.org/10.5194/bg-22-2383-2025
© Author(s) 2025. 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-22-2383-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
21 May 2025
Research article |
| 21 May 2025
| 21 May 2025
Effects of submarine groundwater on nutrient concentration and primary production in a deep bay of the Japan Sea
Menghong Dong
State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
Center for Marine Environmental Studies, Ehime University, Matsuyama, Japan
Takuya Matsuura
Graduate Faculty of Interdisciplinary Research Faculty of Engineering, Civil Engineering and Environmental Engineering, Yamanashi University, Kofu, Japan
Taichi Tebakari
Civil, Human and Environmental Science and Engineering Course, Graduate School of Science and Engineering, Chuo University, Tokyo, Japan
Jing Zhang
Faculty of Science, Academic Assembly, University of Toyama, Toyama, Japan
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Menghong Dong and Xinyu Guo
Ocean Sci., 20, 1527–1546, https://doi.org/10.5194/os-20-1527-2024, https://doi.org/10.5194/os-20-1527-2024, 2024
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We employed a gradient-based algorithm to identify the position and intensity of the fronts in a coastal sea using sea surface temperature data, thereby quantifying their variations. Our study provides a comprehensive analysis of these fronts, elucidating their seasonal variability, intra-tidal dynamics, and the influence of winds on the fronts. By capturing the temporal and spatial dynamics of these fronts, our understanding of the complex oceanographic processes within this region is enhanced.
Menghong Dong and Xinyu Guo
Ocean Sci., 20, 1527–1546, https://doi.org/10.5194/os-20-1527-2024, https://doi.org/10.5194/os-20-1527-2024, 2024
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We employed a gradient-based algorithm to identify the position and intensity of the fronts in a coastal sea using sea surface temperature data, thereby quantifying their variations. Our study provides a comprehensive analysis of these fronts, elucidating their seasonal variability, intra-tidal dynamics, and the influence of winds on the fronts. By capturing the temporal and spatial dynamics of these fronts, our understanding of the complex oceanographic processes within this region is enhanced.
Qian Leng, Xinyu Guo, Junying Zhu, and Akihiko Morimoto
Biogeosciences, 20, 4323–4338, https://doi.org/10.5194/bg-20-4323-2023, https://doi.org/10.5194/bg-20-4323-2023, 2023
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Using a numerical model, we revealed that a large proportion of nutrients in a semi-enclosed sea (Seto Inland Sea, Japan) comes from the Pacific Ocean and supports about half of the phytoplankton growth in the sea. Such results imply that the human-made management of nutrient load from land needs to consider the presence of oceanic nutrients, which act as a background concentration and are not controlled by human activities.
Lei Lin, Hao Liu, Xiaomeng Huang, Qingjun Fu, and Xinyu Guo
Hydrol. Earth Syst. Sci., 26, 5207–5225, https://doi.org/10.5194/hess-26-5207-2022, https://doi.org/10.5194/hess-26-5207-2022, 2022
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Earth system (climate) model is an important instrument for projecting the global water cycle and climate change, in which tides are commonly excluded due to the much small timescales compared to the climate. However, we found that tides significantly impact the river water transport pathways, transport timescales, and concentrations in shelf seas. Thus, the tidal effect should be carefully considered in earth system models to accurately project the global water and biogeochemical cycle.
Junying Zhu, Jie Shi, and Xinyu Guo
Ocean Sci., 18, 659–673, https://doi.org/10.5194/os-18-659-2022, https://doi.org/10.5194/os-18-659-2022, 2022
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A bottom cold water mass (BCWM) is a widespread physical oceanographic phenomenon among coastal seas. Observations reveal a prominent interannual variation in a BCWM in the Seto Inland Sea during 1994–2015. We found that air–sea heat flux change during the warming season plays an important role in its interannual variation. Comparison with other BCWMs indicates that the size is a key factor for their difference. The findings help understand the response of BCWMs to sea surface forcing change.
Toru Kobari, Taiga Honma, Daisuke Hasegawa, Naoki Yoshie, Eisuke Tsutsumi, Takeshi Matsuno, Takeyoshi Nagai, Takeru Kanayama, Fukutaro Karu, Koji Suzuki, Takahiro Tanaka, Xinyu Guo, Gen Kume, Ayako Nishina, and Hirohiko Nakamura
Biogeosciences, 17, 2441–2452, https://doi.org/10.5194/bg-17-2441-2020, https://doi.org/10.5194/bg-17-2441-2020, 2020
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We report on biological productivity under turbulent nitrate flux amplified with the Kuroshio. Oceanographic observations exhibit that the Kuroshio topographically enhances significant turbulent mixing and nitrate influx to the euphotic zone. Onboard experiments show phytoplankton and microzooplankton growths enhanced with the nitrate flux and a significant microzooplankton grazing on phytoplankton. These rapid and systematic trophodynamics enhance biological productivity in the Kuroshio.
Chao Zhang, Huiwang Gao, Xiaohong Yao, Zongbo Shi, Jinhui Shi, Yang Yu, Ling Meng, and Xinyu Guo
Biogeosciences, 15, 749–765, https://doi.org/10.5194/bg-15-749-2018, https://doi.org/10.5194/bg-15-749-2018, 2018
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This study compares the response of phytoplankton growth in the northwest Pacific to those in the Yellow Sea. In general, larger positive responses of phytoplankton induced by combined nutrients (in the subtropical gyre of the northwest Pacific) than those induced by a single nutrient (in the Kuroshio Extension and the Yellow Sea) from the dust are observed. We also emphasize the importance of an increase in bioavailable P stock for phytoplankton growth following dust addition.
Bing Zhang, Jing Zhang, and Takafumi Yoshida
Hydrol. Earth Syst. Sci., 21, 3417–3425, https://doi.org/10.5194/hess-21-3417-2017, https://doi.org/10.5194/hess-21-3417-2017, 2017
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Since groundwater is the linkage between climate changes and fresh submarine groundwater discharge, the variations of and relationships among monthly groundwater table, rainfall, snowfall, and climate change events from 1985 to 2015 were analyzed by wavelet coherence to discuss the implications for climate changes. The results show the increase in precipitation and the groundwater table, indicating that fresh submarine groundwater discharge flux may increase under climate change.
X. Y. Guo, X.-H. Zhu, Y. Long, and D. J. Huang
Biogeosciences, 10, 6403–6417, https://doi.org/10.5194/bg-10-6403-2013, https://doi.org/10.5194/bg-10-6403-2013, 2013
W. T. Bu, J. Zheng, T. Aono, K. Tagami, S. Uchida, J. Zhang, M. C. Honda, Q. J. Guo, and M. Yamada
Biogeosciences, 10, 2497–2511, https://doi.org/10.5194/bg-10-2497-2013, https://doi.org/10.5194/bg-10-2497-2013, 2013
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The bacteria–protist link as a main route of dissolved organic matter across contrasting productivity areas on the Patagonian Shelf
Ocean alkalinity enhancement (OAE) does not cause cellular stress in a phytoplankton community of the subtropical Atlantic Ocean
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Long-term variations in pH in coastal waters along the Korean Peninsula
The effect of carbonate mineral additions on biogeochemical conditions in surface sediments and benthic–pelagic exchange fluxes
Evaluating ocean alkalinity enhancement as a carbon dioxide removal strategy in the North Sea
Assessing the impacts of simulated ocean alkalinity enhancement on viability and growth of nearshore species of phytoplankton
Responses of microbial metabolic rates to non-equilibrated silicate- versus calcium-based ocean alkalinity enhancement
High metabolic zinc demand within native Amundsen and Ross sea phytoplankton communities determined by stable isotope uptake rate measurements
The influence of zooplankton and oxygen on the particulate organic carbon flux in the Benguela Upwelling System
Reviews and syntheses: Biological indicators of low-oxygen stress in marine water-breathing animals
Temperature-enhanced effects of iron on Southern Ocean phytoplankton
Riverine nutrient impact on global ocean nitrogen cycle feedbacks and marine primary production in an Earth system model
The Northeast Greenland Shelf as a potential late-summer CO2 source to the atmosphere
Spring-neap tidal cycles modulate the strength of the carbon source at the estuary-coast interface
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Estimates of carbon sequestration potential in an expanding Arctic fjord (Hornsund, Svalbard) affected by dark plumes of glacial meltwater
An assessment of ocean alkalinity enhancement using aqueous hydroxides: kinetics, efficiency, and precipitation thresholds
Dissolved nitric oxide in the lower Elbe Estuary and the Port of Hamburg area
Variable contribution of wastewater treatment plant effluents to downstream nitrous oxide concentrations and emissions
Depositional controls and budget of organic carbon burial in fine-grained sediments of the North Sea – the Helgoland Mud Area as a test field
Improved understanding of eutrophication trends, indicators and problem areas using machine learning
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Amplified bottom water acidification rates on the Bering Sea shelf from 1970–2022
Investigating the effect of silicate- and calcium-based ocean alkalinity enhancement on diatom silicification
Ocean alkalinity enhancement using sodium carbonate salts does not lead to measurable changes in Fe dynamics in a mesocosm experiment
Quantification and mitigation of bottom-trawling impacts on sedimentary organic carbon stocks in the North Sea
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Multi-model comparison of trends and controls of near-bed oxygen concentration on the northwest European continental shelf under climate change
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Multiple nitrogen sources for primary production inferred from δ13C and δ15N in the southern Sea of Japan
M. Celeste López-Abbate, John E. Garzón-Cardona, Ricardo Silva, Juan-Carlos Molinero, Laura A. Ruiz-Etcheverry, Ana M. Martínez, Azul S. Gilabert, and Rubén J. Lara
Biogeosciences, 22, 2309–2325, https://doi.org/10.5194/bg-22-2309-2025, https://doi.org/10.5194/bg-22-2309-2025, 2025
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This study explores how microbial dynamics influence the dissolved organic matter (DOM) pool in the Patagonian Shelf. Despite high phytoplankton biomass, selective grazing on fast-growing bacteria led to DOM accumulation, likely due to reduced DOM-consuming bacteria and added egestion compounds. Experiments showed that bacteria not only acted as a carbon sink through mineralization but also transferred assimilated carbon dioxide (CO2) to higher trophic levels.
Librada Ramírez, Leonardo J. Pozzo-Pirotta, Aja Trebec, Víctor Manzanares-Vázquez, José L. Díez, Javier Arístegui, Ulf Riebesell, Stephen D. Archer, and María Segovia
Biogeosciences, 22, 1865–1886, https://doi.org/10.5194/bg-22-1865-2025, https://doi.org/10.5194/bg-22-1865-2025, 2025
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We studied the potential effects of increasing ocean alkalinity on a natural plankton community in subtropical waters of the Atlantic near Gran Canaria, Spain. Alkalinity is the capacity of water to resist acidification, and plankton are usually microscopic plants (phytoplankton) and animals (zooplankton), often less than 2.5 cm in length. This study suggests that increasing ocean alkalinity did not have a significant negative impact on the plankton community studied.
Leissing Frederick, Mauricio A. Urbina, and Ruben Escribano
Biogeosciences, 22, 1839–1852, https://doi.org/10.5194/bg-22-1839-2025, https://doi.org/10.5194/bg-22-1839-2025, 2025
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Evidence shows that due to global warming, zooplankton inhabiting the coastal upwelling zone are exposed to increasing hypoxia affecting their physiology, metabolism, and population dynamics. The adaptive responses of zooplankton to cope with mild/severe hypoxia may depend on trade-offs with other metabolic/energy demands, implying less energy for growth, feeding, and reproduction, with ecological consequences for the zooplankton population and the marine food web.
Sören Iwe, Oliver Schmale, and Bernd Schneider
Biogeosciences, 22, 1767–1779, https://doi.org/10.5194/bg-22-1767-2025, https://doi.org/10.5194/bg-22-1767-2025, 2025
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We present a novel method for quantifying N2 fixation by cyanobacteria, which is crucial in Baltic Sea eutrophication. Our Gas Equilibrium – Membrane-Inlet Mass Spectrometer (GE-MIMS), designed for operation on voluntary observing ships (VOSs), enables large-scale monitoring of surface water N2 depletion caused by N2 fixation. Laboratory tests confirm the device’s accuracy and precision, ensuring that it can complement current methods and contribute valuable data for better understanding N2 fixation in the Baltic Sea.
Yong-Woo Lee, Mi-Ok Park, Seong-Gil Kim, Tae-Hoon Kim, Yong Hwa Oh, Sang Heon Lee, and DongJoo Joung
Biogeosciences, 22, 675–690, https://doi.org/10.5194/bg-22-675-2025, https://doi.org/10.5194/bg-22-675-2025, 2025
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Long-term pH variation in coastal waters along the Korean Peninsula was assessed for the first time, and it exhibited no significant pH change over an 11-year period. This contrasts with the ongoing pH decline in open oceans and other coastal areas. Analysis of environmental data showed that pH is mainly controlled by dissolved oxygen in bottom waters. This suggests that ocean warming could cause a pH decline in Korean coastal waters, affecting many fish and seaweed aquaculture operations.
Kadir Biçe, Tristen Myers Stewart, George G. Waldbusser, and Christof Meile
Biogeosciences, 22, 641–657, https://doi.org/10.5194/bg-22-641-2025, https://doi.org/10.5194/bg-22-641-2025, 2025
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We studied the effect of addition of carbonate minerals on coastal sediments. We carried out laboratory experiments to quantify the dissolution kinetics and integrated these observations into a numerical model that describes biogeochemical cycling in surficial sediments. Using the model, we demonstrate the buffering effect of the mineral additions and their duration. We quantify the effect under different environmental conditions and assess the potential for increased atmospheric CO2 uptake.
Feifei Liu, Ute Daewel, Jan Kossack, Kubilay Timur Demir, Helmuth Thomas, and Corinna Schrum
EGUsphere, https://doi.org/10.5194/egusphere-2025-81, https://doi.org/10.5194/egusphere-2025-81, 2025
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Ocean Alkalinity Enhancement boosts oceanic CO₂ absorption, offering a climate solution. Using a regional model, we examined OAE in the North Sea, revealing that shallow coastal areas achieve higher CO₂ uptake than offshore, where alkalinity is more susceptible to deep-ocean loss. Long-term carbon storage is limited, and pH shifts vary by location. Our findings guide OAE deployment to optimize carbon removal while minimizing ecological effects, supporting global climate mitigation efforts.
Jessica L. Oberlander, Mackenzie E. Burke, Cat A. London, and Hugh L. MacIntyre
Biogeosciences, 22, 499–512, https://doi.org/10.5194/bg-22-499-2025, https://doi.org/10.5194/bg-22-499-2025, 2025
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Ocean alkalinity enhancement (OAE) is a promising negative emission technology that results in the net sequestration of atmospheric carbon. In this paper, we assess the potential impact of OAE on phytoplankton through an analysis of prior studies and the effects of simulated OAE on photosynthetic competence. Our findings suggest that there may be little if any significant impact on most phytoplankton studied to date if OAE is conducted in well-flushed, nearshore environments.
Laura Marín-Samper, Javier Arístegui, Nauzet Hernández-Hernández, and Ulf Riebesell
Biogeosciences, 21, 5707–5724, https://doi.org/10.5194/bg-21-5707-2024, https://doi.org/10.5194/bg-21-5707-2024, 2024
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This study exposed a natural community to two non-CO2-equilibrated ocean alkalinity enhancement (OAE) deployments using different minerals. Adding alkalinity in this manner decreases dissolved CO2, essential for photosynthesis. While photosynthesis was not suppressed, bloom formation was mildly delayed, potentially impacting marine food webs. The study emphasizes the need for further research on OAE without prior equilibration and on its ecological implications.
Riss M. Kell, Rebecca J. Chmiel, Deepa Rao, Dawn M. Moran, Matthew R. McIlvin, Tristan J. Horner, Nicole L. Schanke, Ichiko Sugiyama, Robert B. Dunbar, Giacomo R. DiTullio, and Mak A. Saito
Biogeosciences, 21, 5685–5706, https://doi.org/10.5194/bg-21-5685-2024, https://doi.org/10.5194/bg-21-5685-2024, 2024
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Despite interest in modeling the biogeochemical uptake and cycling of the trace metal zinc (Zn), measurements of Zn uptake in natural marine phytoplankton communities have not been conducted previously. To fill this gap, we employed a stable isotope uptake rate measurement method to quantify Zn uptake into natural phytoplankton assemblages within the Southern Ocean. Zn demand was high and rapid enough to depress the inventory of Zn available to phytoplankton on seasonal timescales.
Luisa Chiara Meiritz, Tim Rixen, Anja Karin van der Plas, Tarron Lamont, and Niko Lahajnar
Biogeosciences, 21, 5261–5276, https://doi.org/10.5194/bg-21-5261-2024, https://doi.org/10.5194/bg-21-5261-2024, 2024
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Moored and drifting sediment trap experiments in the northern (nBUS) and southern (sBUS) Benguela Upwelling System showed that active carbon fluxes by vertically migrating zooplankton were about 3 times higher in the sBUS than in the nBUS. Despite these large variabilities, the mean passive particulate organic carbon (POC) fluxes were almost equal in the two subsystems. The more intense near-bottom oxygen minimum layer seems to lead to higher POC fluxes and accumulation rates in the nBUS.
Michael R. Roman, Andrew H. Altieri, Denise Breitburg, Erica M. Ferrer, Natalya D. Gallo, Shin-ichi Ito, Karin Limburg, Kenneth Rose, Moriaki Yasuhara, and Lisa A. Levin
Biogeosciences, 21, 4975–5004, https://doi.org/10.5194/bg-21-4975-2024, https://doi.org/10.5194/bg-21-4975-2024, 2024
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Oxygen-depleted ocean waters have increased worldwide. In order to improve our understanding of the impacts of this oxygen loss on marine life it is essential that we develop reliable indicators that track the negative impacts of low oxygen. We review various indicators of low-oxygen stress for marine animals including their use, research needs, and application to confront the challenges of ocean oxygen loss.
Charlotte Eich, Mathijs van Manen, J. Scott P. McCain, Loay J. Jabre, Willem H. van de Poll, Jinyoung Jung, Sven B. E. H. Pont, Hung-An Tian, Indah Ardiningsih, Gert-Jan Reichart, Erin M. Bertrand, Corina P. D. Brussaard, and Rob Middag
Biogeosciences, 21, 4637–4663, https://doi.org/10.5194/bg-21-4637-2024, https://doi.org/10.5194/bg-21-4637-2024, 2024
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Phytoplankton growth in the Southern Ocean (SO) is often limited by low iron (Fe) concentrations. Sea surface warming impacts Fe availability and can affect phytoplankton growth. We used shipboard Fe clean incubations to test how changes in Fe and temperature affect SO phytoplankton. Their abundances usually increased with Fe addition and temperature increase, with Fe being the major factor. These findings imply potential shifts in ecosystem structure, impacting food webs and elemental cycling.
Miriam Tivig, David P. Keller, and Andreas Oschlies
Biogeosciences, 21, 4469–4493, https://doi.org/10.5194/bg-21-4469-2024, https://doi.org/10.5194/bg-21-4469-2024, 2024
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Marine biological production is highly dependent on the availability of nitrogen and phosphorus. Rivers are the main source of phosphorus to the oceans but poorly represented in global model oceans. We include dissolved nitrogen and phosphorus from river export in a global model ocean and find that the addition of riverine phosphorus affects marine biology on millennial timescales more than riverine nitrogen alone. Globally, riverine phosphorus input increases primary production rates.
Esdoorn Willcox, Marcos Lemes, Thomas Juul-Pedersen, Mikael Kristian Sejr, Johnna Marchiano Holding, and Søren Rysgaard
Biogeosciences, 21, 4037–4050, https://doi.org/10.5194/bg-21-4037-2024, https://doi.org/10.5194/bg-21-4037-2024, 2024
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In this work, we measured the chemistry of seawater from samples obtained from different depths and locations off the east coast of the Northeast Greenland National Park to determine what is influencing concentrations of dissolved CO2. Historically, the region has always been thought to take up CO2 from the atmosphere, but we show that it is possible for the region to become a source in late summer. We discuss the variables that may be related to such changes.
Vlad A. Macovei, Louise C. V. Rewrie, Rüdiger Röttgers, and Yoana G. Voynova
EGUsphere, https://doi.org/10.5194/egusphere-2024-2643, https://doi.org/10.5194/egusphere-2024-2643, 2024
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A commercial vessel equipped with scientific instruments regularly travelled between two large macro-tidal estuaries. We found that biogeochemical variability in the outer estuaries is driven by the 14-day spring-neap tidal cycle, with strong effects on dissolved inorganic and organic carbon concentrations and distribution. Since this land-sea interface effect increases the strength of the carbon source to the atmosphere by 74 % during spring tide, it should be accounted for in regional models.
Lennart Thomas Bach, Aaron James Ferderer, Julie LaRoche, and Kai Georg Schulz
Biogeosciences, 21, 3665–3676, https://doi.org/10.5194/bg-21-3665-2024, https://doi.org/10.5194/bg-21-3665-2024, 2024
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Ocean alkalinity enhancement (OAE) is an emerging marine CO2 removal method, but its environmental effects are insufficiently understood. The OAE Pelagic Impact Intercomparison Project (OAEPIIP) provides funding for a standardized and globally replicated microcosm experiment to study the effects of OAE on plankton communities. Here, we provide a detailed manual for the OAEPIIP experiment. We expect OAEPIIP to help build scientific consensus on the effects of OAE on plankton.
Marlena Szeligowska, Déborah Benkort, Anna Przyborska, Mateusz Moskalik, Bernabé Moreno, Emilia Trudnowska, and Katarzyna Błachowiak-Samołyk
Biogeosciences, 21, 3617–3639, https://doi.org/10.5194/bg-21-3617-2024, https://doi.org/10.5194/bg-21-3617-2024, 2024
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The European Arctic is experiencing rapid regional warming, causing glaciers that terminate in the sea to retreat onto land. Due to this process, the area of a well-studied fjord, Hornsund, has increased by around 100 km2 (40%) since 1976. Combining satellite and in situ data with a mathematical model, we estimated that, despite some negative consequences of glacial meltwater release, such emerging coastal waters could mitigate climate change by increasing carbon uptake and storage by sediments.
Mallory C. Ringham, Nathan Hirtle, Cody Shaw, Xi Lu, Julian Herndon, Brendan R. Carter, and Matthew D. Eisaman
Biogeosciences, 21, 3551–3570, https://doi.org/10.5194/bg-21-3551-2024, https://doi.org/10.5194/bg-21-3551-2024, 2024
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Ocean alkalinity enhancement leverages the large surface area and carbon storage capacity of the oceans to store atmospheric CO2 as dissolved bicarbonate. We monitored CO2 uptake in seawater treated with NaOH to establish operational boundaries for carbon removal experiments. Results show that CO2 equilibration occurred on the order of weeks to months, was consistent with values expected from equilibration calculations, and was limited by mineral precipitation at high pH and CaCO3 saturation.
Riel Carlo O. Ingeniero, Gesa Schulz, and Hermann W. Bange
Biogeosciences, 21, 3425–3440, https://doi.org/10.5194/bg-21-3425-2024, https://doi.org/10.5194/bg-21-3425-2024, 2024
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Our research is the first to measure dissolved NO concentrations in temperate estuarine waters, providing insights into its distribution under varying conditions and enhancing our understanding of its production processes. Dissolved NO was supersaturated in the Elbe Estuary, indicating that it is a source of atmospheric NO. The observed distribution of dissolved NO most likely resulted from nitrification.
Weiyi Tang, Jeff Talbott, Timothy Jones, and Bess B. Ward
Biogeosciences, 21, 3239–3250, https://doi.org/10.5194/bg-21-3239-2024, https://doi.org/10.5194/bg-21-3239-2024, 2024
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Wastewater treatment plants (WWTPs) are known to be hotspots of greenhouse gas emissions. However, the impact of WWTPs on the emission of the greenhouse gas N2O in downstream aquatic environments is less constrained. We found spatially and temporally variable but overall higher N2O concentrations and fluxes in waters downstream of WWTPs, pointing to the need for efficient N2O removal in addition to the treatment of nitrogen in WWTPs.
Daniel Müller, Bo Liu, Walter Geibert, Moritz Holtappels, Lasse Sander, Elda Miramontes, Heidi Taubner, Susann Henkel, Kai-Uwe Hinrichs, Denise Bethke, Ingrid Dohrmann, and Sabine Kasten
EGUsphere, https://doi.org/10.5194/egusphere-2024-1632, https://doi.org/10.5194/egusphere-2024-1632, 2024
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Coastal and shelf sediments are the most important sinks for organic carbon (OC) on Earth. We produced a new high-resolution sediment and pore-water dataset from the Helgoland Mud Area (HMA), North Sea, to determine, which depositional factors control the preservation of OC. The burial efficiency is highest in an area of high sedimentation and terrigenous OC. The HMA covers 0.09 % of the North Sea, but accounts for 0.76 % of its OC accumulation, highlighting the importance of the depocentre.
Deep S. Banerjee and Jozef Skakala
EGUsphere, https://doi.org/10.22541/essoar.171405637.76928549/v1, https://doi.org/10.22541/essoar.171405637.76928549/v1, 2024
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Nitrate is a crucial nutrient in oceans. Excess nutrients can trigger uncontrolled algae growth (eutrophication), damaging marine ecosystems. We used a machine learning tool to generate a skilled, gap-free, bi-decadal surface nitrate dataset from sparse observations. This dataset reveals areas on the North West European Shelf at risk of eutrophication, bi-decadal trends in coastal nitrate, and an impact of winter nitrate on spring phytoplankton blooms.
Amanda Y. L. Cheong, Kogila Vani Annammala, Ee Ling Yong, Yongli Zhou, Robert S. Nichols, and Patrick Martin
Biogeosciences, 21, 2955–2971, https://doi.org/10.5194/bg-21-2955-2024, https://doi.org/10.5194/bg-21-2955-2024, 2024
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We measured nutrients and dissolved organic matter for 1 year in a eutrophic tropical estuary to understand their sources and cycling. Our data show that the dissolved organic matter originates partly from land and partly from microbial processes in the water. Internal recycling is likely important for maintaining high nutrient concentrations, and we found that there is often excess nitrogen compared to silicon and phosphorus. Our data help to explain how eutrophication persists in this system.
Darren Pilcher, Jessica Cross, Natalie Monacci, Linquan Mu, Kelly Kearney, Albert Hermann, and Wei Cheng
EGUsphere, https://doi.org/10.5194/egusphere-2024-1096, https://doi.org/10.5194/egusphere-2024-1096, 2024
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The Bering Sea shelf is a highly productive marine ecosystem that is vulnerable to ocean acidification. We use a computational model to simulate the carbon cycle and acidification rates from 1970–2022. The results suggest that bottom water acidification rates are more than twice as great as surface rates. Bottom waters are also naturally more acidic, thus these waters will pass key thresholds known to negatively impact marine organisms, such as red king crab, much sooner than surface waters.
Aaron Ferderer, Kai G. Schulz, Ulf Riebesell, Kirralee G. Baker, Zanna Chase, and Lennart T. Bach
Biogeosciences, 21, 2777–2794, https://doi.org/10.5194/bg-21-2777-2024, https://doi.org/10.5194/bg-21-2777-2024, 2024
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Ocean alkalinity enhancement (OAE) is a promising method of atmospheric carbon removal; however, its ecological impacts remain largely unknown. We assessed the effects of simulated silicate- and calcium-based mineral OAE on diatom silicification. We found that increased silicate concentrations from silicate-based OAE increased diatom silicification. In contrast, the enhancement of alkalinity had no effect on community silicification and minimal effects on the silicification of different genera.
David González-Santana, María Segovia, Melchor González-Dávila, Librada Ramírez, Aridane G. González, Leonardo J. Pozzo-Pirotta, Veronica Arnone, Victor Vázquez, Ulf Riebesell, and J. Magdalena Santana-Casiano
Biogeosciences, 21, 2705–2715, https://doi.org/10.5194/bg-21-2705-2024, https://doi.org/10.5194/bg-21-2705-2024, 2024
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In a recent experiment off the coast of Gran Canaria (Spain), scientists explored a method called ocean alkalinization enhancement (OAE), where carbonate minerals were added to seawater. This process changed the levels of certain ions in the water, affecting its pH and buffering capacity. The researchers were particularly interested in how this could impact the levels of essential trace metals in the water.
Lucas Porz, Wenyan Zhang, Nils Christiansen, Jan Kossack, Ute Daewel, and Corinna Schrum
Biogeosciences, 21, 2547–2570, https://doi.org/10.5194/bg-21-2547-2024, https://doi.org/10.5194/bg-21-2547-2024, 2024
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Seafloor sediments store a large amount of carbon, helping to naturally regulate Earth's climate. If disturbed, some sediment particles can turn into CO2, but this effect is not well understood. Using computer simulations, we found that bottom-contacting fishing gears release about 1 million tons of CO2 per year in the North Sea, one of the most heavily fished regions globally. We show how protecting certain areas could reduce these emissions while also benefitting seafloor-living animals.
Jiaying A. Guo, Robert F. Strzepek, Kerrie M. Swadling, Ashley T. Townsend, and Lennart T. Bach
Biogeosciences, 21, 2335–2354, https://doi.org/10.5194/bg-21-2335-2024, https://doi.org/10.5194/bg-21-2335-2024, 2024
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Ocean alkalinity enhancement aims to increase atmospheric CO2 sequestration by adding alkaline materials to the ocean. We assessed the environmental effects of olivine and steel slag powder on coastal plankton. Overall, slag is more efficient than olivine in releasing total alkalinity and, thus, in its ability to sequester CO2. Slag also had less environmental effect on the enclosed plankton communities when considering its higher CO2 removal potential based on this 3-week experiment.
Giovanni Galli, Sarah Wakelin, James Harle, Jason Holt, and Yuri Artioli
Biogeosciences, 21, 2143–2158, https://doi.org/10.5194/bg-21-2143-2024, https://doi.org/10.5194/bg-21-2143-2024, 2024
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This work shows that, under a high-emission scenario, oxygen concentration in deep water of parts of the North Sea and Celtic Sea can become critically low (hypoxia) towards the end of this century. The extent and frequency of hypoxia depends on the intensity of climate change projected by different climate models. This is the result of a complex combination of factors like warming, increase in stratification, changes in the currents and changes in biological processes.
Sandy E. Tenorio and Laura Farías
Biogeosciences, 21, 2029–2050, https://doi.org/10.5194/bg-21-2029-2024, https://doi.org/10.5194/bg-21-2029-2024, 2024
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Time series studies show that CH4 is highly dynamic on the coastal ocean surface and planktonic communities are linked to CH4 accumulation, as found in coastal upwelling off Chile. We have identified the crucial role of picoplankton (> 3 µm) in CH4 recycling, especially with the addition of methylated substrates (trimethylamine and methylphosphonic acid) during upwelling and non-upwelling periods. These insights improve understanding of surface ocean CH4 recycling, aiding CH4 emission estimates.
Charlotte A. J. Williams, Tom Hull, Jan Kaiser, Claire Mahaffey, Naomi Greenwood, Matthew Toberman, and Matthew R. Palmer
Biogeosciences, 21, 1961–1971, https://doi.org/10.5194/bg-21-1961-2024, https://doi.org/10.5194/bg-21-1961-2024, 2024
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Oxygen (O2) is a key indicator of ocean health. The risk of O2 loss in the productive coastal/continental slope regions is increasing. Autonomous underwater vehicles equipped with O2 optodes provide lots of data but have problems resolving strong vertical O2 changes. Here we show how to overcome this and calculate how much O2 is supplied to the low-O2 bottom waters via mixing. Bursts in mixing supply nearly all of the O2 to bottom waters in autumn, stopping them reaching ecologically low levels.
Sabine Schmidt and Ibrahima Iris Diallo
Biogeosciences, 21, 1785–1800, https://doi.org/10.5194/bg-21-1785-2024, https://doi.org/10.5194/bg-21-1785-2024, 2024
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Along the French coast facing the Bay of Biscay, the large Gironde and Loire estuaries suffer from hypoxia. This prompted a study of the small Charente estuary located between them. This work reveals a minimum oxygen zone in the Charente estuary, which extends for about 25 km. Temperature is the main factor controlling the hypoxia. This calls for the monitoring of small turbid macrotidal estuaries that are vulnerable to hypoxia, a risk expected to increase with global warming.
Simone R. Alin, Jan A. Newton, Richard A. Feely, Samantha Siedlecki, and Dana Greeley
Biogeosciences, 21, 1639–1673, https://doi.org/10.5194/bg-21-1639-2024, https://doi.org/10.5194/bg-21-1639-2024, 2024
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We provide a new multi-stressor data product that allows us to characterize the seasonality of temperature, O2, and CO2 in the southern Salish Sea and delivers insights into the impacts of major marine heatwave and precipitation anomalies on regional ocean acidification and hypoxia. We also describe the present-day frequencies of temperature, O2, and ocean acidification conditions that cross thresholds of sensitive regional species that are economically or ecologically important.
Pamela Linford, Iván Pérez-Santos, Paulina Montero, Patricio A. Díaz, Claudia Aracena, Elías Pinilla, Facundo Barrera, Manuel Castillo, Aida Alvera-Azcárate, Mónica Alvarado, Gabriel Soto, Cécile Pujol, Camila Schwerter, Sara Arenas-Uribe, Pilar Navarro, Guido Mancilla-Gutiérrez, Robinson Altamirano, Javiera San Martín, and Camila Soto-Riquelme
Biogeosciences, 21, 1433–1459, https://doi.org/10.5194/bg-21-1433-2024, https://doi.org/10.5194/bg-21-1433-2024, 2024
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The Patagonian fjords comprise a world region where low-oxygen water and hypoxia conditions are observed. An in situ dataset was used to quantify the mechanism involved in the presence of these conditions in northern Patagonian fjords. Water mass analysis confirmed the contribution of Equatorial Subsurface Water in the advection of the low-oxygen water, and hypoxic conditions occurred when the community respiration rate exceeded the gross primary production.
Ting Wang, Buyun Du, Inke Forbrich, Jun Zhou, Joshua Polen, Elsie M. Sunderland, Prentiss H. Balcom, Celia Chen, and Daniel Obrist
Biogeosciences, 21, 1461–1476, https://doi.org/10.5194/bg-21-1461-2024, https://doi.org/10.5194/bg-21-1461-2024, 2024
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The strong seasonal increases of Hg in aboveground biomass during the growing season and the lack of changes observed after senescence in this salt marsh ecosystem suggest physiologically controlled Hg uptake pathways. The Hg sources found in marsh aboveground tissues originate from a mix of sources, unlike terrestrial ecosystems, where atmospheric GEM is the main source. Belowground plant tissues mostly take up Hg from soils. Overall, the salt marsh currently serves as a small net Hg sink.
Eleanor Simpson, Debby Ianson, Karen E. Kohfeld, Ana C. Franco, Paul A. Covert, Marty Davelaar, and Yves Perreault
Biogeosciences, 21, 1323–1353, https://doi.org/10.5194/bg-21-1323-2024, https://doi.org/10.5194/bg-21-1323-2024, 2024
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Shellfish aquaculture operates in nearshore areas where data on ocean acidification parameters are limited. We show daily and seasonal variability in pH and saturation states of calcium carbonate at nearshore aquaculture sites in British Columbia, Canada, and determine the contributing drivers of this variability. We find that nearshore locations have greater variability than open waters and that the uptake of carbon by phytoplankton is the major driver of pH and saturation state variability.
S. Alejandra Castillo Cieza, Rachel H. R. Stanley, Pierre Marrec, Diana N. Fontaine, E. Taylor Crockford, Dennis J. McGillicuddy Jr., Arshia Mehta, Susanne Menden-Deuer, Emily E. Peacock, Tatiana A. Rynearson, Zoe O. Sandwith, Weifeng Zhang, and Heidi M. Sosik
Biogeosciences, 21, 1235–1257, https://doi.org/10.5194/bg-21-1235-2024, https://doi.org/10.5194/bg-21-1235-2024, 2024
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The coastal ocean in the northeastern USA provides many services, including fisheries and habitats for threatened species. In summer 2019, a bloom occurred of a large unusual phytoplankton, the diatom Hemiaulus, with nitrogen-fixing symbionts. This led to vast changes in productivity and grazing rates in the ecosystem. This work shows that the emergence of one species can have profound effects on ecosystem function. Such changes may become more prevalent as the ocean warms due to climate change.
Claudine Hauri, Brita Irving, Sam Dupont, Rémi Pagés, Donna D. W. Hauser, and Seth L. Danielson
Biogeosciences, 21, 1135–1159, https://doi.org/10.5194/bg-21-1135-2024, https://doi.org/10.5194/bg-21-1135-2024, 2024
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Arctic marine ecosystems are highly susceptible to impacts of climate change and ocean acidification. We present pH and pCO2 time series (2016–2020) from the Chukchi Ecosystem Observatory and analyze the drivers of the current conditions to get a better understanding of how climate change and ocean acidification could affect the ecological niches of organisms.
William Hiles, Lucy C. Miller, Craig Smeaton, and William E. N. Austin
Biogeosciences, 21, 929–948, https://doi.org/10.5194/bg-21-929-2024, https://doi.org/10.5194/bg-21-929-2024, 2024
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Saltmarsh soils may help to limit the rate of climate change by storing carbon. To understand their impacts, they must be accurately mapped. We use drone data to estimate the size of three saltmarshes in NE Scotland. We find that drone imagery, combined with tidal data, can reliably inform our understanding of saltmarsh size. When compared with previous work using vegetation communities, we find that our most reliable new estimates of stored carbon are 15–20 % smaller than previously estimated.
De'Marcus Robinson, Anh L. D. Pham, David J. Yousavich, Felix Janssen, Frank Wenzhöfer, Eleanor C. Arrington, Kelsey M. Gosselin, Marco Sandoval-Belmar, Matthew Mar, David L. Valentine, Daniele Bianchi, and Tina Treude
Biogeosciences, 21, 773–788, https://doi.org/10.5194/bg-21-773-2024, https://doi.org/10.5194/bg-21-773-2024, 2024
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The present study suggests that high release of ferrous iron from the seafloor of the oxygen-deficient Santa Barabara Basin (California) supports surface primary productivity, creating positive feedback on seafloor iron release by enhancing low-oxygen conditions in the basin.
David J. Yousavich, De'Marcus Robinson, Xuefeng Peng, Sebastian J. E. Krause, Frank Wenzhöfer, Felix Janssen, Na Liu, Jonathan Tarn, Franklin Kinnaman, David L. Valentine, and Tina Treude
Biogeosciences, 21, 789–809, https://doi.org/10.5194/bg-21-789-2024, https://doi.org/10.5194/bg-21-789-2024, 2024
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Declining oxygen (O2) concentrations in coastal oceans can threaten people’s ways of life and food supplies. Here, we investigate how mats of bacteria that proliferate on the seafloor of the Santa Barbara Basin sustain and potentially worsen these O2 depletion events through their unique chemoautotrophic metabolism. Our study shows how changes in seafloor microbiology and geochemistry brought on by declining O2 concentrations can help these mats grow as well as how that growth affects the basin.
Krysten Rutherford, Katja Fennel, Lina Garcia Suarez, and Jasmin G. John
Biogeosciences, 21, 301–314, https://doi.org/10.5194/bg-21-301-2024, https://doi.org/10.5194/bg-21-301-2024, 2024
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We downscaled two mid-century (~2075) ocean model projections to a high-resolution regional ocean model of the northwest North Atlantic (NA) shelf. In one projection, the NA shelf break current practically disappears; in the other it remains almost unchanged. This leads to a wide range of possible future shelf properties. More accurate projections of coastal circulation features would narrow the range of possible outcomes of biogeochemical projections for shelf regions.
Lennart Thomas Bach
Biogeosciences, 21, 261–277, https://doi.org/10.5194/bg-21-261-2024, https://doi.org/10.5194/bg-21-261-2024, 2024
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Ocean alkalinity enhancement (OAE) is a widely considered marine carbon dioxide removal method. OAE aims to accelerate chemical rock weathering, which is a natural process that slowly sequesters atmospheric carbon dioxide. This study shows that the addition of anthropogenic alkalinity via OAE can reduce the natural release of alkalinity and, therefore, reduce the efficiency of OAE for climate mitigation. However, the additionality problem could be mitigated via a variety of activities.
Tsuneo Ono, Daisuke Muraoka, Masahiro Hayashi, Makiko Yorifuji, Akihiro Dazai, Shigeyuki Omoto, Takehiro Tanaka, Tomohiro Okamura, Goh Onitsuka, Kenji Sudo, Masahiko Fujii, Ryuji Hamanoue, and Masahide Wakita
Biogeosciences, 21, 177–199, https://doi.org/10.5194/bg-21-177-2024, https://doi.org/10.5194/bg-21-177-2024, 2024
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We carried out parallel year-round observations of pH and related parameters in five stations around the Japan coast. It was found that short-term acidified situations with Omega_ar less than 1.5 occurred at four of five stations. Most of such short-term acidified events were related to the short-term low salinity event, and the extent of short-term pH drawdown at high freshwater input was positively correlated with the nutrient concentration of the main rivers that flow into the coastal area.
K. Mareike Paul, Martijn Hermans, Sami A. Jokinen, Inda Brinkmann, Helena L. Filipsson, and Tom Jilbert
Biogeosciences, 20, 5003–5028, https://doi.org/10.5194/bg-20-5003-2023, https://doi.org/10.5194/bg-20-5003-2023, 2023
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Seawater naturally contains trace metals such as Mo and U, which accumulate under low oxygen conditions on the seafloor. Previous studies have used sediment Mo and U contents as an archive of changing oxygen concentrations in coastal waters. Here we show that in fjords the use of Mo and U for this purpose may be impaired by additional processes. Our findings have implications for the reliable use of Mo and U to reconstruct oxygen changes in fjords.
Hannah Sharpe, Michel Gosselin, Catherine Lalande, Alexandre Normandeau, Jean-Carlos Montero-Serrano, Khouloud Baccara, Daniel Bourgault, Owen Sherwood, and Audrey Limoges
Biogeosciences, 20, 4981–5001, https://doi.org/10.5194/bg-20-4981-2023, https://doi.org/10.5194/bg-20-4981-2023, 2023
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We studied the impact of submarine canyon processes within the Pointe-des-Monts system on biogenic matter export and phytoplankton assemblages. Using data from three oceanographic moorings, we show that the canyon experienced two low-amplitude sediment remobilization events in 2020–2021 that led to enhanced particle fluxes in the deep-water column layer > 2.6 km offshore. Sinking phytoplankton fluxes were lower near the canyon compared to background values from the lower St. Lawrence Estuary.
Dewi Langlet, Florian Mermillod-Blondin, Noémie Deldicq, Arthur Bauville, Gwendoline Duong, Lara Konecny, Mylène Hugoni, Lionel Denis, and Vincent M. P. Bouchet
Biogeosciences, 20, 4875–4891, https://doi.org/10.5194/bg-20-4875-2023, https://doi.org/10.5194/bg-20-4875-2023, 2023
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Benthic foraminifera are single-cell marine organisms which can move in the sediment column. They were previously reported to horizontally and vertically transport sediment particles, yet the impact of their motion on the dissolved fluxes remains unknown. Using microprofiling, we show here that foraminiferal burrow formation increases the oxygen penetration depth in the sediment, leading to a change in the structure of the prokaryotic community.
Masahiko Fujii, Ryuji Hamanoue, Lawrence Patrick Cases Bernardo, Tsuneo Ono, Akihiro Dazai, Shigeyuki Oomoto, Masahide Wakita, and Takehiro Tanaka
Biogeosciences, 20, 4527–4549, https://doi.org/10.5194/bg-20-4527-2023, https://doi.org/10.5194/bg-20-4527-2023, 2023
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This is the first study of the current and future impacts of climate change on Pacific oyster farming in Japan. Future coastal warming and acidification may affect oyster larvae as a result of longer exposure to lower-pH waters. A prolonged spawning period may harm oyster processing by shortening the shipping period and reducing oyster quality. To minimize impacts on Pacific oyster farming, in addition to mitigation measures, local adaptation measures may be required.
Taketoshi Kodama, Atsushi Nishimoto, Ken-ichi Nakamura, Misato Nakae, Naoki Iguchi, Yosuke Igeta, and Yoichi Kogure
Biogeosciences, 20, 3667–3682, https://doi.org/10.5194/bg-20-3667-2023, https://doi.org/10.5194/bg-20-3667-2023, 2023
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Carbon and nitrogen are essential elements for organisms; their stable isotope ratios (13C : 12C, 15N : 14N) are useful tools for understanding turnover and movement in the ocean. In the Sea of Japan, the environment is rapidly being altered by human activities. The 13C : 12C of small organic particles is increased by active carbon fixation, and phytoplankton growth increases the values. The 15N : 14N variations suggest that nitrates from many sources contribute to organic production.
Cited articles
Aoki, T.: Analysis of Regional Populations: A Case Study of Five Areas of the Toyama Prefecture, J. Kanazawa Seiryo Univ., 55, 1–8, 2021.
Bratton, J. F.: The three scales of submarine groundwater flow and discharge across passive continental margins, J. Geol., 118, 565–575, https://doi.org/10.1086/655114, 2010.
Burnett, W. C., Taniguchi, M., and Oberdorfer, J.: Measurement and significance of the direct discharge of groundwater into the coastal zone, J. Sea Res., 46, 109–116, https://doi.org/10.1016/S1385-1101(01)00075-2, 2001.
Burnett, W. C., Bokuniewicz, H., Moore, W. S., and Taniguchi, M.: Groundwater and pore water inputs to the coastal zone, Biogeochemistry, 66, 3–33, 2003.
Cho, H. M., Kim, G., Kwon, E. Y., Moosdorf, N., Garcia-Orellana, J., and Santos, I. R.: Radium tracing nutrient inputs through submarine groundwater discharge in the global ocean, Sci. Rep., 8, 1–7, https://doi.org/10.1038/s41598-018-20806-2, 2018.
Church, T. M.: An Underground Route for the Water Cycle, Nature, 380, 579–580, 1996.
Cloern, J. E., Foster, S. Q., and Kleckner, A. E.: Phytoplankton primary production in the world's estuarine-coastal ecosystems, Biogeosciences, 11, 2477–2501, https://doi.org/10.5194/bg-11-2477-2014, 2014.
Dong, M., Guo, X., Matsuura, T., Tebakari, T., and Zhang, J.: Dataset of article: Evaluation of the Effects of Submarine Groundwater on Nutrient Concentration and Primary Production in a Deep Bay of the Japan Sea, Zenodo [data set], https://doi.org/10.5281/zenodo.11075610, 2024.
Fasham, M. J. R., Ducklow, H. W., and McKelvie, S. M.: A nitrogen-based model of plankton dynamics in the oceanic mixed layer, J. Mar. Res., 48, 591–639, 1990.
Grid Point Value of Meso-Scale Model: http://database.rish.kyoto-u.ac.jp/arch/jmadata/data/gpv/netcdf/MSM-S/, last access: 10 August 2024.
Guo, X. and Yanagi, T.: The Role of the Taiwan Strait in an Ecological Model in the East China Sea, Acta Oceanogr. Taiwanica, 37, 139–164, 1998.
Hatta, M. and Zhang, J.: Temporal changes and impacts of submarine fresh groundwater discharge to the coastal environment: A decadal case study in Toyama Bay, Japan, J. Geophys. Res.-Ocean., 118, 2610–2622, https://doi.org/10.1002/jgrc.20184, 2013.
Hatta, M., Zhang, J., Satake, H., Ishizaka, J., and Nakauchi, Y.: Water mass structure and fresh water fluxes (riverine and SGD's) into Toyama Bay, Chikyukagaku (Geochemistry), 39, 157–164, https://doi.org/10.14934/chikyukagaku.39.157, 2005.
Hwang, D.-W., Lee, Y.-W., and Kim, G.: Large submarine groundwater discharge and benthic eutrophication in Bangdu Bay on volcanic Jeju Island, Korea, Limnol. Oceanogr., 50, 1393–1403, https://doi.org/10.4319/lo.2005.50.5.1393, 2005.
Igeta, Y., Yankovsky, A., Fukudome, K. I., Ikeda, S., Okei, N., Ayukawa, K., Kaneda, A., and Watanabe, T.: Transition of the Tsushima Warm Current path observed over Toyama Trough, Japan, J. Phys. Oceanogr., 47, 2721–2739, https://doi.org/10.1175/JPO-D-17-0027.1, 2017.
Igeta, Y., Kuga, M., Yankovsky, A., Wagawa, T., Fukudome, K. ichi, Kaneda, A., Ikeda, S., Tsuji, T., and Hirose, N.: Effect of a current trapped by a continental slope on the pathway of a coastal current crossing Toyama Trough, Japan, J. Oceanogr., 77, 685–701, https://doi.org/10.1007/s10872-021-00601-w, 2021.
Iguchi, N.: Spring diel migration of a euphausiid Euphausia pacifica in Toyama Bay, southern Japan Sea, Bull. Japan Sea Natl. Fish. Res. Inst., 45, 59–68, 1995.
Ishizu, M., Miyazawa, Y., Tsunoda, T., and Guo, X.: Development of a biogeochemical and carbon model related to ocean acidification indices with an operational ocean model product in the North Western Pacific, Sustainability, 11, 2677, https://doi.org/10.3390/su11092677, 2019.
Itahashi, S., Hayashi, K., Takeda, S., Umezawa, Y., Matsuda, K., Sakurai, T., and Uno, I.: Nitrogen burden from atmospheric deposition in East Asian oceans in 2010 based on high-resolution regional numerical modeling, Environ. Pollut., 286, 117309, https://doi.org/10.1016/j.envpol.2021.117309, 2021.
Japan Meteorological Agency: Climate Change Monitoring Report 2023, Japan Meteorological Agency, Japan Meteorological Agency, https://www.jma.go.jp/jma/en/NMHS/ccmr/ccmr2023.pdf (last access: 23 February 2025), 2024.
Jiao, J. and Post, V.: Submarine Groundwater Discharge, in: Coastal Hydrogeology, Cambridge University Press, 187–214, https://doi.org/10.1017/9781139344142, 2019.
Kantún-Manzano, C. A., Herrera-Silveira, J. A., and Arcega-Cabrera, F.: Influence of Coastal Submarine Groundwater Discharges on Seagrass Communities in a Subtropical Karstic Environment, Bull. Environ. Contam. Toxicol., 100, 176–183, https://doi.org/10.1007/s00128-017-2259-3, 2018.
Katazakai, S. and Zhang, J.: A quarter-century of nutrient load reduction leads to halving river nutrient fluxes and increasing nutrient limitation in coastal waters of central Japan, Environ. Monit. Assess., 193, 573, https://doi.org/10.1007/s10661-021-09279-5, 2021a.
Katazakai, S. and Zhang, J.: A Shift from Snow to Rain in Midlatitude Japan Increases Fresh Submarine Groundwater Discharge and Doubled Inorganic Carbon Flux over 20 Years, Environ. Sci. Technol., 55, 14667–14675, https://doi.org/10.1021/acs.est.1c05108, 2021b.
Kawamiya, M.: Mechanism of offshore nutrient supply in the western Arabian Sea, J. Mar. Res., 59, 675–696, 2001.
Kondo, J.: Air-sea bulk transfer coefficients in diabatic conditions, Bound.-Lay. Meteorol., 9, 91–112, 1975.
Koyama, Y., Zhang, J., Hagiwara, T., Satake, H., and Asai, K.: Flow measurement of submarine groundwater discharge at wide area in the Eastern Toyama Bay, Chikyukagaku (Geochemistry), 39, 149–155, 2005.
Kreuzburg, M., Scholten, J., Hsu, F.-H., Liebetrau, V., SultenfuB, J., Rapaglia, J., and Schluter, M.: Submarine Groundwater Discharge-Derived Nutrient Fluxes in Eckernförde Bay (Western Baltic Sea), Estuar. Coasts, 46, 1190–1207, 2023.
Lapointe, B. E., O'Connell, J. D., and Garrett, G. S.: Nutrient couplings between on-site sewage disposal systems, groundwaters, and nearshore surface waters of the Florida Keys, Biogeochemistry, 10, 289–307, 1990.
Lecher, A. L. and Mackey, K. R. M.: Synthesizing the effects of submarine groundwater discharge on Marine Biota, Hydrology, 5, 1–21, https://doi.org/10.3390/hydrology5040060, 2018.
Leng, Q., Guo, X., Zhu, J., and Morimoto, A.: Contribution of the open ocean to the nutrient and phytoplankton inventory in a semi-enclosed coastal sea, Biogeosciences, 20, 4323–4338, https://doi.org/10.5194/bg-20-4323-2023, 2023.
Lenhart, H.-J. and Große, F.: Assessing the effects of WFD nutrient reductions within an OSPAR frame using trans-boundary nutrient modeling, Front. Mar. Sci., 5, 1–19, https://doi.org/10.3389/fmars.2018.00447, 2018.
Lenhart, H., Desmit, X., Große, F., Mills, D., Lacroix, G., Los, H., Ménesguen, A., Pätsch, J., Troost, T., Van der Molen, J., Van Leeuwen, S., and Wakelin, S.: “Distance to target” modelling assessment, OSPAR commission, 1–80 pp., 2013.
Luijendijk, E., Gleeson, T., and Moosdorf, N.: Fresh groundwater discharge insignificant for the world's oceans but important for coastal ecosystems, Nat. Commun., 11, 1–12, https://doi.org/10.1038/s41467-020-15064-8, 2020.
Luo, M., Zhang, Y., Xiao, K., Wang, X., Zhang, X., Li, G., and Li, H.: Effect of submarine groundwater discharge on nutrient distribution and eutrophication in Liaodong Bay, China, Water Res., 247, 120732, https://doi.org/10.1016/J.WATRES.2023.120732, 2023.
Luoma, S., Majaniemi, J., Pullinen, A., Mursu, J., and Virtasalo, J. J.: Geological and groundwater flow model of a submarine groundwater discharge site at Hanko (Finland), northern Baltic Sea, Hydrogeol. J., 29, 1279–1297, https://doi.org/10.1007/s10040-021-02313-3, 2021.
Matsuura, T. and Tebakari, T.: Impact of precipitation changes due to climate change on NO3-N in the Kurobe River, Japanese Assoc. Groundw. Hydrol. 2022 Fall Lect., 192–196, 2022.
Matsuura, T., Harada, K., and Tebakari, T.: Impact of the diffusion of public sewage systems in Toyama Prefecture on nitrogen loading in Toyama Bay, Japanese Assoc. Groundw. Hydrol. 2023 Fall Lect., 24–27, 2023.
Mellor, G. and Blumberg, A.: Wave breaking and ocean surface layer thermal response, J. Phys. Oceanogr., 34, 693–698, https://doi.org/10.1175/2517.1, 2004.
Mellor, G. L., Ezer, T., and Oey, L.-Y.: The Pressure Gradient Conundrum of Sigma Coordinate Ocean Models, J. Atmos. Ocean. Technol., 11, 1126–1134, 1994.
Ménesguen, A., Cugier, P., and Leblond, I.: A new numerical technique for tracking chemical species in a multisource, coastal ecosystem applied to nitrogen causing Ulva blooms in the Bay of Brest (France), Limnol. Oceanogr., 51, 591–601, https://doi.org/10.4319/lo.2006.51.1_part_2.0591, 2006.
Ministry of the Environment: The 7th National Survey on the Natural Environment: Report on Shallow Marine Ecosystems Survey (Seaweed Bed Survey), https://www.biodic.go.jp/reports2/6th/6_moba19/6_moba19.pdf (last access: 23 February 2025), 2008.
MIRC: MIRC Ocean Dataset 2005 Documentation, Marine Information Research Center, Marine Information Research Center, http://www.mirc.jha.or.jp/products/MODS2005/MODS2005.pdf (last access: 23 February 2025), 2005.
Miyazawa, Y., Zhang, R., Guo, X., Tamura, H., Ambe, D., Lee, J. S., Okuno, A., Yoshinari, H., Setou, T., and Komatsu, K.: Water mass variability in the western North Pacific detected in a 15-year eddy resolving ocean reanalysis, J. Oceanogr., 65, 737–756, https://doi.org/10.1007/s10872-009-0063-3, 2009.
Moore, W. S.: Large groundwater inputs to coastal waters revealed by 226Ra enrichments, Nature, 380, 612–614, 1996.
Moore, W. S.: The effect of submarine groundwater discharge on the ocean, Ann. Rev. Mar. Sci., 2, 59–88, https://doi.org/10.1146/annurev-marine-120308-081019, 2010.
Müller, T., Gros, J., Leibold, P., Al-Balushi, H., Petermann, E., Schmidt, M., Brückmann, W., Al Kindi, M., and Al-Abri, O. S.: Autonomous Large-Scale Radon Mapping and Buoyant Plume Modeling Quantify Deep Submarine Groundwater Discharge: A Novel Approach Based on a Self-Sufficient Open Ocean Vehicle, Environ. Sci. Technol., 57, 6540–6549, https://doi.org/10.1021/acs.est.3c00786, 2023.
Nakada, S., Isoda, Y., and Uchiyama, I.: Seasonal variations of water properties and the baroclinic flow pattern in Toyama Bay under the influence of the Tsushima Warm Current, J. Oceanogr., 61, 943–952, https://doi.org/10.1007/s10872-006-0011-4, 2005.
Nakaguchi, Y., Yamaguchi, Y., Yamada, H., Zhang, J., Suzuki, M., Koyama, Y., and Hayashi, K.: Characterization and origin of chemical components in the submarine groundwater discharge in Toyama Bay, Chikyukagaku (Geochemistry), 39, 119–130, 2005.
Neumann, T.: The fate of river-borne nitrogen in the Baltic Sea–an example for the River Oder., Estuar. Coast. Shelf Sci., 73, 1–7, 2007.
Northwest Pacific Region Environmental Cooperation Center: Toyama Bay Pilot Study Report, Northwest Pacific Region Environmental Cooperation Center, https://www.npec.or.jp/publicity/pdf/2010/pilotstudy.pdf (last access: 23 February 2025), 2010.
Onitsuka, G. and Yanagi, T.: Differences in ecosystem dynamics between the Northern and Southern parts of the Japan Sea: Analyses with two ecosystem models, J. Oceanogr., 61, 415–433, https://doi.org/10.1007/s10872-005-0051-1, 2005.
Onitsuka, G., Yanagi, T., and Yoon, J. H.: A numerical study on nutrient sources in the surface layer of the Japan Sea using a coupled physical-ecosystem model, J. Geophys. Res.-Ocean., 112, 1–17, https://doi.org/10.1029/2006JC003981, 2007.
Oya, F., Tsuji, T., and Fujiwara, S.: Relative Growth and Feeding Habits of Halfbeak, Hyporhamphus sajori, Larvae and Juveniles in Toyama Bay of the Japan Sea, Aquac., 50, 47–54, 2002.
Painting, S. J., Van der Molen, J., Parker, E. R., Coughlan, C., Birchenough, S., Bolam, S., Aldridge, J. N., Forster, R. M., and Greenwood, N.: Development of indicators of ecosystem functioning in a temperate shelf sea: a combined fieldwork and modelling approach, Biogeochemistry, 113, 237–257, https://doi.org/10.1007/s10533-012-9774-4, 2013.
Paulson, C. A. and Simpson, J. J.: Irradiance Measurements in the Upper Ocean, J. Phys. Oceanogr., 7, 952–956, 1977.
Redfield, A. C., Ketchum, B. H., and Richards, F. A.: The influence of organisms on the composition of seawater, in: The Sea, edited by: Hill, M. N., Interscience Publishers, New York, 26–77, https://doi.org/10.1002/iroh.19630480414, 1963.
Rodellas, V., Garcia-Orellana, J., Masqué, P., Feldman, M., Weinstein, Y., and Boyle, E. A.: Submarine groundwater discharge as a major source of nutrients to the Mediterranean Sea, P. Natl. Acad. Sci. USA, 112, 3926–3930, https://doi.org/10.1073/pnas.1419049112, 2015.
Rosati, A. and Miyakoda, K.: A General Circulation Model for Upper Ocean Simulation, J. Phys. Oceanogr., 18, 1601–1626, 1988.
Santos, I. R., Burnett, W. C., Chanton, J., Dimova, N., and Peterson, R. N.: Land or ocean?: Assessing the driving forces of submarine groundwater discharge at a coastal site in the gulf of mexico, J. Geophys. Res.-Ocean., 114, 1–11, https://doi.org/10.1029/2008JC005038, 2009.
Santos, I. R., Chen, X., Lecher, A. L., Sawyer, A. H., Moosdorf, N., Rodellas, V., Tamborski, J., Cho, H. M., Dimova, N., Sugimoto, R., Bonaglia, S., Li, H., Hajati, M. C., and Li, L.: Submarine groundwater discharge impacts on coastal nutrient biogeochemistry, Nat. Rev. Earth Environ., 2, 307–323, https://doi.org/10.1038/s43017-021-00152-0, 2021.
Silverman, J., Strauch-Gozali, S., and Asfur, M.: The Influence of Fresh Submarine Groundwater Discharge on Seawater Acidification Along the Northern Mediterranean Coast of Israel, J. Geophys. Res.-Ocean., 129, 1–21, https://doi.org/10.1029/2024JC021010, 2024.
Skogen, M. D., Ji, R., Akimova, A., Daewel, U., Hansen, C., Hjøllo, S. S., Van Leeuwen, S. M., Maar, M., Macias, D., Mousing, E. A., Almroth-Rosell, E., Sailley, S. F., Spence, M. A., Troost, T. A., and Van de Wolfshaar, K.: Disclosing the truth: Are models better than observations?, Mar. Ecol. Prog. Ser., 680, 7–13, https://doi.org/10.3354/meps13574, 2021.
Sugimoto, R., Kitagawa, K., Nishi, S., Honda, H., Yamada, M., Kobayashi, S., Shoji, J., Ohsawa, S., Taniguchi, M., and Tominaga, O.: Phytoplankton primary productivity around submarine groundwater discharge in nearshore coasts, Mar. Ecol. Prog. Ser., 563, 25–33, https://doi.org/10.3354/meps11980, 2017.
Taniguchi, M., Burnett, W. C., Cable, J. E., and Turner, J. V.: Investigation of submarine groundwater discharge, Hydrol. Process., 16, 2115–2129, https://doi.org/10.1002/hyp.1145, 2002.
Taylor, G. T., Gobler, C. J., and Sañudo-Wilhelmy, S. A.: Speciation and concentrations of dissolved nitrogen as determinants of brown tide Aureococcus anophagefferens bloom initiation, Mar. Ecol. Prog. Ser., 312, 67–83, https://doi.org/10.3354/meps312067, 2006.
Tsujimoto, R.: Seasonal Changes in the Nutrient and Phytoplankton Biomass in the Surface Water of the Innermost Area of Toyama Bay, Bull. Coast. Oceanogr., 49, 127–137, https://doi.org/10.1177/000276426300601008, 2012.
Varlamov, S., Miyazawa, Y., and Guo, X.: Regional nested tide-resolving real-time JCOPET modeling system for coastal waters of southern Japan, in: 2nd International Workshop on Modeling the Ocean (IWMO), 24–26 May 2010, Old Dominion University in Norfolk, VA, USA, http://www.ccpo.odu.edu/~tezer/IWMO_2010/PRESENTATIONS/WEDNESDAY_pdf/Varlamov_NestedSys_Japan.pdf (last access: 23 February 2025), 2010.
Wang, S.-L., Chen, C.-T. A., Huang, T.-H., Tseng, H.-C., Lui, H.-K., Peng, T.-R., Kandasamy, S., Zhang, J., Yang, L., Gao, X., Lou, J.-Y., Kuo, F.-W., Chen, X.-G., Ye, Y., and Lin, Y.-J.: Submarine Groundwater Discharge helps making nearshore waters heterotrophic, Sci. Rep., 8, 1–10, https://doi.org/10.1038/s41598-018-30056-x, 2018.
Wang, X., Du, J., Ji, T., Wen, T., Liu, S., and Zhang, J.: An estimation of nutrient fluxes via submarine groundwater discharge into the Sanggou Bay—A typical multi-species culture ecosystem in China, Mar. Chem., 167, 113–122, https://doi.org/10.1016/j.marchem.2014.07.002, 2014.
Watanabe, Y., Matsuura, T., and Chiba, H.: Variability of summer water-mass structure in Toyama bay coastal-zone, Oceanogr. Japan, 22, 97–117, https://doi.org/10.5928/kaiyou.22.4_97, 2013.
Wilson, S. J., Moody, A., McKenzie, T., Cardenas, M. B., Luijendijk, E., Sawyer, A. H., Wilson, A., Michael, H. A., Xu, B., Knee, K. L., Cho, H. M., Weinstein, Y., Paytan, A., Moosdorf, N., Chen, C. T. A., Beck, M., Lopez, C., Murgulet, D., Kim, G., Charette, M. A., Waska, H., Ibánhez, J. S. P., Chaillou, G., Oehler, T., Onodera, S. ichi, Saito, M., Rodellas, V., Dimova, N., Montiel, D., Dulai, H., Richardson, C., Du, J., Petermann, E., Chen, X., Davis, K. L., Lamontagne, S., Sugimoto, R., Wang, G., Li, H., Torres, A. I., Demir, C., Bristol, E., Connolly, C. T., McClelland, J. W., Silva, B. J., Tait, D., Kumar, B. S. K., Viswanadham, R., Sarma, V. V. S. S., Silva-Filho, E., Shiller, A., Lecher, A., Tamborski, J., Bokuniewicz, H., Rocha, C., Reckhardt, A., Böttcher, M. E., Jiang, S., Stieglitz, T., Gbewezoun, H. G. V., Charbonnier, C., Anschutz, P., Hernández-Terrones, L. M., Babu, S., Szymczycha, B., Sadat-Noori, M., Niencheski, F., Null, K., Tobias, C., Song, B., Anderson, I. C., and Santos, I. R.: Global subterranean estuaries modify groundwater nutrient loading to the ocean, Limnol. Oceanogr. Lett., 9, 411–422, https://doi.org/10.1002/lol2.10390, 2024.
Xu, C., Wang, X., Zhang, F., Lao, Y., Liu, J., and Du, J.: Potential Linkages Between Submarine Groundwater (Fresh and Saline) Nutrient Inputs and Eutrophication in a Coastal Aquaculture Bay, J. Geophys. Res.-Ocean., 129, e2024JC021501, https://doi.org/10.1029/2024JC021501, 2024a.
Xu, H., Xu, B., Yu, H., Zhao, S., Burnett, W. C., Yao, Q., Dimova, N. T., Song, S., Guo, X., Chen, X., Zhang, H., and Yu, Z.: Deciphering Multi-Scale Submarine Groundwater Discharge in a Typical Eutrophic Bay, J. Geophys. Res.-Ocean., 129, 1–15, https://doi.org/10.1029/2024JC021042, 2024b.
Zektser, I. S.: Groundwater and the environment: applications for the global community, edited by: Everett, L. G., Lewis Publishers, 175 pp., http://archive.org/details/groundwaterenvir0000zekt (last access: 23 February 2025), 2000.
Zhang, J. and Satake, H.: The chemical characteristics of submarine groundwater seepage in Toyama Bay, Central Japan, edited by: Taniguchi, M., Wang, K., and Gamo, T., Elsevier B.V., 45–60 pp., https://doi.org/10.1016/B978-044451479-0/50016-9, 2003.
Zhang, J., Hagiwara, T., Koyama, Y., Satake, H., Nakamura, T., and Asai, K.: A new flow rate measuring method - SGD (submarine groundwater discharge) flux chamber and its approach off Katakai Alluvial Fan, Toyama Bay, Central Japan, Chikyukagaku (Geochemistry), 39, 141–148, 2005.
Zhang, J., Guo, X., and Zhao, L.: Tracing external sources of nutrients in the East China Sea and evaluating their contributions to primary production, Prog. Oceanogr., 176, 102122, https://doi.org/10.1016/j.pocean.2019.102122, 2019.
Zhang, Y., Santos, I. R., Li, H., Wang, Q., Xiao, K., Guo, H., and Wang, X.: Submarine groundwater discharge drives coastal water quality and nutrient budgets at small and large scales, Geochim. Cosmochim. Ac., 290, 201–215, https://doi.org/10.1016/j.gca.2020.08.026, 2020.
Short summary
Submarine groundwater discharge (SGD), a common coastal hydrological process that involves submarine inflow of groundwater into the sea, is associated with a large nutrient load. To clarify the distribution of SGD-derived nutrients after release at the bottom of the sea and their contribution to phytoplankton growth in the marine ecosystem, we modeled the SGD process in Toyama Bay using a specialized computer code that can distinguish SGD-derived nutrients from nutrients from other sources.
Submarine groundwater discharge (SGD), a common coastal hydrological process that involves...
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