Article
Chemistry, Multidisciplinary
Hung-An Tian, Mathijs van Manen, Flora Wille, Jinyoung Jung, SangHoon Lee, Tae-Wan Kim, Shigeru Aoki, Charlotte Eich, Corina P. D. Brussaard, Gert-Jan Reichart, Tim M. Conway, Rob Middag
Summary: This study presents the first combined dataset of dissolved and particulate zinc (Zn) and cadmium (Cd) in the Amundsen Sea (AS), providing insights into their sources and biogeochemical processes. The Circumpolar Deep Water (CDW) is identified as the main source for both elements, while aerosol deposition, ice shelf melt, and sea ice melt are considered insignificant sources. Biological uptake is the dominant process for the cycling of Zn and Cd, while sediment resuspension and ice shelf melt contribute little to particulate Zn and Cd. The findings have implications for the larger-scale cycling of trace metals in the Southern Ocean.
Article
Chemistry, Multidisciplinary
Mathijs Van Manen, Shigeru Aoki, Corina P. D. Brussaard, Tim M. Conway, Charlotte Eich, Loes J. A. Gerringa, Jinyoung Jung, Tae -Wan Kim, SangHoon Lee, Youngju Lee, Gert-Jan Reichart, Hung-An Tian, Flora Wille, Rob Middag
Summary: Coastal areas around Antarctica are important sources of trace metals and hotspots of biological activity. However, these areas are also experiencing the effects of climate change, including thinning ice sheets. In the Amundsen Sea Polynya, dissolved iron and manganese concentrations were found to be depleted at the surface, indicating biological uptake or precipitation. Near the Dotson Ice Shelf, surface concentrations of manganese were elevated, while iron concentrations were surprisingly low. Particulate iron and manganese concentrations were elevated throughout the water column near the ice shelf. Inflowing modified circumpolar deep water and benthic sediments were identified as important sources of iron and manganese in the polynya. Refractory iron and manganese likely have a lithogenic source, while labile fractions are mostly biogenic in surface waters and authigenic in deep waters. Different uptake ratios were compared, suggesting that a range of values is better at capturing natural variability. Climate change may increase the melting of the Dotson Ice Shelf, leading to increased input of iron and manganese into the polynya, potentially fueling primary productivity.
Article
Environmental Sciences
Manuel Colombo, Birgit Rogalla, Jingxuan Li, Susan E. Allen, Kristin J. Orians, Maria T. Maldonado
Summary: Research shows that the Canadian Arctic Archipelago region's sediment resuspension and sediment-water interactions result in the enrichment of iron in water bodies, which are then transported to Baffin Bay, providing crucial support for primary production and nitrogen fixation in the region and beyond.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Geochemistry & Geophysics
Ruifeng Zhang, Jingling Ren, Zhaoru Zhang, Zhu Zhu, Seth John
Summary: Trace metals play important roles as micronutrients in the oceans and can act as tracers for various processes. China's marginal seas are influenced by biological cycling, river inputs, atmospheric deposition, and anthropogenic pollution, impacting the distribution of trace metals.
Article
Chemistry, Multidisciplinary
H. R. Hunt, B. A. Summers, M. Sieber, S. Krisch, A. Al-Hashem, M. Hopwood, E. P. Achterberg, T. M. Conway
Summary: Iron isotopic composition has become a widely used tool for determining the sources and evaluating the biogeochemical cycling of dissolved iron in the oceans. Studies show that the distribution of dissolved iron in the South Atlantic can largely be explained by water mass mixing, suggesting that dissolved iron isotopic signatures can be used as tracers of deep ocean iron transport.
Article
Environmental Sciences
Donato Giovannelli
Summary: Biogeochemistry is influenced by a small group of microbial-encoded proteins with redox-sensitive transition metals. Understanding the impact of metal distribution and availability on microbial diversity will provide crucial insights into the coevolution of Earth and life.
NATURE REVIEWS EARTH & ENVIRONMENT
(2023)
Review
Geochemistry & Geophysics
Jessica N. Fitzsimmons, Tim M. Conway
Summary: The micronutrient iron is crucial in determining the primary production in the global ocean. Understanding the sources, sinks, and internal cycling processes of iron is essential to comprehend its role in the global carbon cycle and climate change. Iron isotopic analysis in seawater has proved to be an effective tool in identifying iron sources and studying biogeochemical processes. This review provides a summary of the different iron source fluxes and their isotopic signatures, as well as the potential of iron isotopes in studying internal oceanic cycling of iron.
ANNUAL REVIEW OF MARINE SCIENCE
(2023)
Article
Environmental Sciences
Xue-Gang Chen, Stephan Krisch, Ali Al-Hashem, Mark James Hopwood, Michiel M. Rutgers van der Loeff, Oliver Huhn, Pablo Lodeiro, Tim Steffens, Eric P. Achterberg
Summary: This study investigates the distribution patterns of dissolved, labile, and total particulate trace metals (TMs) on the Northeast Greenland shelf. The results suggest that TM dynamics are primarily controlled by the mixing between North Atlantic-derived Intermediate Water and Arctic surface waters. The discrepancies in TM transport between submarine meltwater and Arctic surface water may alter the stoichiometry of dTMs and LpTMs on the shelf.
GLOBAL BIOGEOCHEMICAL CYCLES
(2022)
Article
Environmental Sciences
Morgane M. G. Perron, Bernadette C. Proemse, Michal Strzelec, Melanie Gault-Ringold, Andrew R. Bowie
Summary: This study reports the first atmospheric measurements of iron concentration and solubility near and downwind of the Heard and McDonald Islands on the Kerguelen plateau, highlighting the significant impact of volcanic emissions on the iron supply to marine ecosystems.
ENVIRONMENTAL SCIENCE-ATMOSPHERES
(2021)
Article
Agronomy
Zhang Wei, Thomas M. R. Maxwell, Brett Robinson, Nicholas Dickinson
Summary: This study investigates whether species coexistence can improve nutrient uptake in mid-altitude grasslands, and the results suggest that species combinations can facilitate mutual nutrient acquisition.
Article
Geosciences, Multidisciplinary
Te Liu, Mark J. Hopwood, Stephan Krisch, Lucia H. Vieira, Eric P. Achterberg
Summary: Wet deposition is identified as an additional source of trace metals (TMs) to the Congo plume, supplementing the TM input from the Congo River. The study shows the significant contribution of wet deposition to the TM fluxes in the Congo plume, including Cd, Cu, Pb, and Zn.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
David Gonzalez-Santana, Alastair J. M. Lough, Helene Planquette, Geraldine Sarthou, Alessandro Tagliabue, Maeve C. Lohan
Summary: Hydrothermal vent sites along mid-ocean ridges are important sources of reduced chemical species and trace elements. A study found that the dissolved iron (II) (dFe(II)) concentrations ranged from 0.00 to 0.12 nmol L-1 in non-hydrothermally affected regions, and as high as 12.8 nmol L-1 within hydrothermal plumes. This suggests that dFe(II) plays a more significant role in the iron pool than previously thought.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Mohammad Nuruzzama, Waliur Rahaman, Rahul Mohan
Summary: Coastal lakes in Antarctica receive significant amounts of ions and trace elements during the austral summer, with dissolved concentrations lower than average seawater. Sea-salt spray and chemical weathering are dominant sources, while phosphate and molybdenum act as limiting nutrients. Dissolved copper plays a key role in organic matter decomposition, and excess barium in lake sediments suggests significant removal during transport.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Oceanography
Laramie T. Jensen, Jay T. Cullen, Sarah L. Jackson, Loes J. A. Gerringa, Dorothea Bauch, Rob Middag, Robert M. Sherrell, Jessica N. Fitzsimmons
Summary: Recent studies have revealed a unique linear relationship between dissolved copper (Cu) and nickel (Ni) in the Arctic Ocean, which differs from other oceans. This relationship is driven by river inputs and shows distinct distribution patterns in surface and deep waters. Cu and Ni mainly originate from rivers, but Ni is additionally influenced by biological processes and shelf sediment processes, while Cu is mostly affected by mixing.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Chemistry, Multidisciplinary
Rob Middag, John M. Rolison, Ejin George, Loes J. A. Gerringa, Micha J. A. Rijkenberg, Claudine H. Stirling
Summary: The study found that the dissolved metal concentrations in the Mediterranean Sea are influenced by the Atlantic Ocean, resulting in increased surface concentrations. Atmospheric deposition is also identified as an important source of these metals. Regular basin wide assessments of trace metal distributions in the Mediterranean are needed to confirm or detect trends in dissolved metal concentrations in the deep basin.
Review
Geochemistry & Geophysics
Douglas S. Hamilton, Morgane M. G. Perron, Tami C. Bond, Andrew R. Bowie, Rebecca R. Buchholz, Cecile Guieu, Akinori Ito, Willy Maenhaut, Stelios Myriokefalitakis, Nazli Olgun, Sagar D. Rathod, Kerstin Schepanski, Alessandro Tagliabue, Robert Wagner, Natalie M. Mahowald
Summary: Atmospheric deposition plays a crucial role in supplying nutrients to marine phytoplankton, which is the base of marine food webs. Understanding the spatial and temporal variability of nutrient-bearing aerosols from various sources and their impact on the ocean is essential for studying marine ecosystems.
ANNUAL REVIEW OF MARINE SCIENCE
(2022)
Article
Environmental Sciences
Abigail J. R. Smith, Talitha Nelson, Lavenia Ratnarajah, Cristina Genovese, Karen Westwood, Thomas M. Holmes, Matthew Corkill, Ashley T. Townsend, Elanor Bell, Kathrin Wuttig, Delphine Lannuzel
Summary: The availability of iron to marine microbial communities is enhanced through complexation by ligands. This study investigates the distribution and likely sources of Fe-binding ligands in the Mertz Glacier Region, East Antarctica. The results show that ligand concentrations vary spatially and are influenced by phytoplankton Fe uptake in surface waters and by upwelled circumpolar deep water and particle remineralisation in benthic nepheloid layers over the shelf. Sea-ice melt appears to support bacterial production in areas where Fe and ligands are exhausted.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Clara R. Vives, Christina Schallenberg, Peter G. Strutton, Karen J. Westwood
Summary: Phytoplankton production plays a crucial role in the carbon cycle and global climate regulation. In the Southern Ocean, micronutrient iron and light are important factors limiting phytoplankton growth. A recent study found that adding iron can enhance phytoplankton growth under high light conditions.
JOURNAL OF MARINE SYSTEMS
(2022)
Article
Geochemistry & Geophysics
Layla Creac'h, Taryn L. Noble, Zanna Chase, Bruce L. A. Charlier, Ashley T. Townsend, Habacuc Perez-Tribouillier, Christian Dietz
Summary: Determining past changes in ocean circulation on the Antarctic margin is important, but the current proxy methods are limited. This study evaluates the use of neodymium isotopes as a proxy for ocean circulation along the Wilkes Land continental rise. The results show the potential of seawater neodymium isotopes as water mass signatures, but further research is needed to develop reliable proxies for Antarctic water masses.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geosciences, Multidisciplinary
Laura A. Dalman, Christina Schallenberg, Alexander D. Fraser, Sophie Bestley, Eun Jin Yang, Lesley Clementson, Klaus M. Meiners
Summary: Microalgae in Antarctic sea ice are crucial for early-season production in Southern Ocean ecosystems. This study investigates the absorption coefficients, pigments, and community composition of ice algae and non-algal particles in pack ice off East Antarctica and the Weddell Sea. The results show that ice algae dominate particulate absorption in both regions. Light conditions influence pigment production and community composition.
JOURNAL OF MARINE SYSTEMS
(2023)
Letter
Limnology
Clara R. Vives, Christina Schallenberg, Peter G. Strutton, Philip W. Boyd
Summary: In the Southern Ocean, understanding the timing of phytoplankton blooms is crucial for studying ecosystem dynamics and carbon export. Previous studies have yielded inconsistent findings regarding bloom timing. This study compares bloom dynamics based on different diagnostics and highlights the importance of considering phytoplankton physiology when choosing proxies for their growth.
LIMNOLOGY AND OCEANOGRAPHY LETTERS
(2023)
Article
Environmental Sciences
P. Latour, P. van der Merwe, K. Wuttig, M. Corkill, A. T. Townsend, T. M. Holmes, S. R. Rintoul, C. K. Weldrick, R. F. Strzepek, M. Gault-Ringold, R. Schlitzer, A. R. Bowie
Summary: This study investigates the potential export of Mn-rich Antarctic shelf waters towards depleted open Southern Ocean waters. The results show that while high Mn concentrations were observed over the shelf, biological uptake decreased dissolved Mn concentrations in surface waters north of the South Antarctic Circumpolar Current Front, limiting its export. However, bottom waters exhibited a decrease in dissolved Mn concentrations with distance from the coast, indicating potential lateral export.
GLOBAL BIOGEOCHEMICAL CYCLES
(2023)
Article
Multidisciplinary Sciences
Jonathan S. Stark, Glenn J. Johnstone, Catherine King, Tania Raymond, Allison Rutter, Scott C. Stark, Ashley T. Townsend
Summary: This study investigated the presence of contaminants in marine sediments near Casey Station in East Antarctica and found higher concentrations of most contaminants at disturbed locations. The spatial distribution of sediment properties and contaminants displayed intricate patterns of variation. Some contaminants exceeded international guidelines for sediment quality. The study concluded that Antarctic research stations may pose a moderate level of long-term ecological risk to local marine ecosystems, and raised awareness and monitoring programs are recommended.
Article
Biodiversity Conservation
Helene Aflenzer, Linn Hoffmann, Thomas Holmes, Kathrin Wuttig, Cristina Genovese, Andrew Ross Bowie
Summary: Low bioavailability of iron limits primary production in the Southern Ocean, and the growth of phytoplankton species in this region is influenced by the interaction between iron bioavailability and temperature. Future climate conditions may lead to changes in phytoplankton community structures and carbon sequestration efficiency in certain regions of the ocean that experience higher temperature and greater iron supply.
Article
Water Resources
Sibele C. Nascimento, David R. Cooke, Ashley T. Townsend, Garry Davidson, Anita Parbhakar-Fox, Matthew J. Cracknell, Clare B. Miller
Summary: Inadequate management of mine waste at Mount Lyell Copper Mine in western Tasmania has negatively impacted the Queen-King Rivers and Macquarie Harbour. Water quality in the river system has been monitored every six months for the past two decades to investigate the long-term hydrochemical and environmental effects of historical mine practices and waste. The presence of dissolved metals and the low pH levels in the water indicate ongoing contamination and a risk to the downstream environment.
MINE WATER AND THE ENVIRONMENT
(2023)
Article
Environmental Sciences
Cathryn Ann Wynn-Edwards, Elizabeth H. Shadwick, Peter Jansen, Christina Schallenberg, Tanya Lea Maurer, Adrienne J. Sutton
Summary: Understanding the size and future changes of natural ocean carbon sinks is critical for the projection of atmospheric CO2 levels. The mechanism behind the variability of the Southern Ocean carbon flux is still debated and accurate observations are limited. This study evaluated the accuracy of CO2 partial pressure estimates from biogeochemical floats in the Southern Ocean using data collected over a year. The results showed that the differences in pCO(2) estimates between platforms were within tolerable uncertainties, highlighting the importance of continued validation efforts.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Cristina Genovese, Marco Grotti, Francisco Ardini, Matthew J. Corkill, Luis P. Duprat, Kathrin Wuttig, Ashley T. Townsend, Delphine Lannuzel
Summary: This study investigates the distribution, concentration, and potential drivers of iron-binding ligands in Antarctic sea ice. Results show that the concentration of ligands varies spatially and seasonally, with the lowest concentration in winter sea ice and the highest concentration in springtime. The study suggests that sea ice acts as a potential biogeochemical bridge between autumn and spring phytoplankton blooms.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2023)
Article
Chemistry, Multidisciplinary
Morgane Leon, Pieter van Beek, Virginie Sanial, Marc Souhaut, Paul Henderson, Matthew A. Charette
Summary: The analysis of radium and actinium isotopes in seawater requires the collection of large volumes of water and the use of high sensitivity instruments. To concentrate these isotopes, filters impregnated with MnO2 are typically used. However, the extraction efficiency of these filters for the target isotopes needs to be determined.
