Article
Multidisciplinary Sciences
Lennart T. Bach, Philip W. Boyd
Summary: Mitigating global climate change requires gigaton-scale carbon dioxide removal, with oceans as a potential source. Natural analogs of marine carbon dioxide removal can bridge the gap between numerical simulations and experimental studies, providing valuable insights without the need for legal permission. By identifying and studying these natural analogs, it can fast-forward the urgently needed assessment of marine carbon dioxide removal methods.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Linda M. Westermann, Ian D. E. A. Lidbury, Chun-Yang Li, Ning Wang, Andrew R. J. Murphy, Maria del Mar Aguilo Ferretjans, Mussa Quareshy, Muralidharan Shanmugan, Alberto Torcello-Requena, Eleonora Silvano, Yu-Zhong Zhang, Claudia A. Blindauer, Yin Chen, David J. Scanlan
Summary: In marine systems, the degradation of phospholipids, such as phosphocholine and phosphorylethanolamine, is essential for the biogeochemical cycling of phosphorus, nitrogen, and carbon. Transporters for ethanolamine and choline are common and abundant in the global ocean, indicating the significance of phospholipid catabolism in situ. This study provides genetic and biochemical evidence for the complete catabolic pathways of phospholipids in marine bacteria, highlighting their role in primary production and nutrient utilization.
Article
Ecology
Valeria Di Biagio, Stefano Salon, Laura Feudale, Gianpiero Cossarini
Summary: This study investigates the subsurface oxygen maximum (SOM) in the Mediterranean Sea, showing different characteristics between the western and eastern Mediterranean in summer. The model-derived concentrations and depths are in agreement with estimations from the literature and display mesoscale variability patterns.
Review
Biochemistry & Molecular Biology
Patricia Sanchez-Baracaldo, Giorgio Bianchini, Jamie D. Wilson, Andrew H. Knoll
Summary: Cyanobacteria, as the only prokaryotes with oxygenic photosynthesis, have had a significant impact on the biology and chemistry of our planet. Genomic and evolutionary studies have enriched our understanding of early phototrophs and their role in the global carbon cycle. Cyanobacteria diversified after the Great Oxidation Event and played a crucial role in shaping the Earth's environment.
TRENDS IN MICROBIOLOGY
(2022)
Article
Environmental Sciences
Christopher J. Somes, Andrew W. Dale, Klaus Wallmann, Florian Scholz, Wanxuan Yao, Andreas Oschlies, Juan Muglia, Andreas Schmittner, Eric P. Achterberg
Summary: This study used a global dissolved iron data set and model simulations to investigate the sources and scavenging fluxes of marine iron, finding that improving the variable ligand parameterization in the model is key to enhancing global marine iron cycle models. High source fluxes of atmospheric soluble iron deposition and reductive sedimentary iron release improved the model's performance, but there are limitations due to underrepresented ligands near source inputs.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Geosciences, Multidisciplinary
Folco Giomi, Alberto Barausse, Alexandra Steckbauer, Daniele Daffonchio, Carlos M. Duarte, Marco Fusi
Summary: The decline of dissolved oxygen in the oceans could have negative impacts on marine life and biogeochemical cycles. Current models that focus on large-scale mean values may lead to inaccurate predictions. Short-term and small-scale oxygen fluctuations strongly influence marine ecosystems, but they are often neglected in large-scale modelling. Understanding the dynamics of dissolved oxygen at small relevant scales is crucial for accurate projection of the impacts of ocean and coastal deoxygenation on marine biogeochemical processes and communities.
Article
Multidisciplinary Sciences
Enrico Ser-Giacomi, Ricardo Martinez-Garcia, Stephanie Dutkiewicz, Michael J. Follows
Summary: Marine plankton are essential for carbon storage, global climate, and ecosystem function. This study introduces a new theoretical framework to track and model the dynamics of a drifting ecosystem embedded in a moving and diluting water patch. The research highlights the importance of considering physical processes and patch heterogeneity in interpreting and modeling marine ecosystems.
NATURE COMMUNICATIONS
(2023)
Article
Environmental Sciences
Sung-Ching Lee, Sara H. Knox, Ian McKendry, T. Andrew Black
Summary: In Canada, it is expected that area burned, number of fires, seasonal fire severity, and fire season length will increase. However, the ecosystem feedbacks to these changes are still largely unknown. This study conducted measurements in forest and wetland ecosystems during four smoke episodes to assess the impacts on gross primary production (GPP). The results revealed that smoke affected shortwave irradiance, heat fluxes, and carbon dioxide (CO2) exchanges, with varying responses depending on the timing and density of the smoke.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Limnology
Tinkara Tinta, Katja Klun, Gerhard J. Herndl
Summary: Jellyfish blooms are a significant but often overlooked source of organic matter in the ocean, with potential impacts on microbial communities and ecosystem dynamics. This study compares the composition and release rates of organic matter from living jellyfish with that stored in jellyfish biomass, emphasizing the different roles these two pools of jelly-OM play in the marine environment. Major knowledge gaps are also highlighted for future research.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Review
Geosciences, Multidisciplinary
Dominik Zak, Michael Hupfer, Alvaro Cabezas, Gerald Jurasinski, Joachim Audet, Andreas Kleeberg, Robert McInnes, Soren Munch Kristiansen, Rasmus Jes Petersen, Haojie Liu, Tobias Goldhammer
Summary: Sulphate concentrations in freshwater have been increasing globally over the past few decades, but the extent of its impact on ecosystems remains poorly understood. Sources of sulphate pollution include natural processes like weathering and anthropogenic activities such as mining and agriculture, affecting biogeochemical processes and potentially harming aquatic organisms and human health. Solutions such as bioremediation systems and wetland restoration may help mitigate these impacts.
EARTH-SCIENCE REVIEWS
(2021)
Article
Multidisciplinary Sciences
Loay J. Jabre, Andrew E. Allen, J. Scott P. McCain, John P. McCrow, Nancy Tenenbaum, Jenna L. Spackeen, Rachel E. Sipler, Beverley R. Green, Deborah A. Bronk, David A. Hutchins, Erin M. Bertrand
Summary: The study found that increased iron availability and warming in the Southern Ocean can significantly enhance nutrient uptake and primary productivity in surface ocean microbial communities, with a greater effect observed under simultaneous iron addition and warming. Furthermore, the dominant diatom Pseudo-nitzschia showed increased abundance under warming conditions, attributed to its up-regulation of iron-conserving photosynthetic processes and improved iron uptake and storage mechanisms. These findings highlight important physiological differences between diatom groups and suggest potential shifts in phytoplankton assemblages and nutrient cycling in iron-limited Southern Ocean ecosystems under warming conditions.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Oceanography
Minming Cui, Anand Gnanadesikan
Summary: Copper distribution in the ocean differs from other nutrients like phosphate and silicate. Our study suggests that diatoms in the Southern Ocean play a particularly important role in marine copper distributions. The uptake of copper in the Southern Ocean is substantially higher than in other oceanic regions.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Soil Science
Ling Xiong, Chaoxiang Yuan, Qiqian Wu, Dario A. Fornara, Petr Hedenec, Siying Chen, Yan Peng, Zemin Zhao, Fuzhong Wu, Kai Yue
Summary: The removal of understory vegetation has negative effects on soil biogeochemical properties, emphasizing the importance of managing understory vegetation.
APPLIED SOIL ECOLOGY
(2024)
Article
Biology
Yasuto Watanabe, Eiichi Tajika, Kazumi Ozaki
Summary: Iron is a vital element for life and its geochemical cycle is intricately connected to the intertwined history of life and the environment on Earth. Geological records suggest that ferruginous waters were present in the ancient oceans before and after the Great Oxidation Event. However, there is still ambiguity regarding the interaction and evolution of the biogeochemical cycles of oxygen and iron during the Archean-Proterozoic.
Article
Biochemistry & Molecular Biology
Matthew McLean, David Mouillot, Aurore A. Maureaud, Tarek Hattab, M. Aaron MacNeil, Eric Goberville, Martin Lindegren, Georg Engelhard, Malin Pinsky, Arnaud Auber
Summary: As climate change progresses, species are moving towards the poles while subtropical and tropical species are entering temperate environments. The Community Temperature Index (CTI) has been widely used to track the mean thermal affinity of a community, showing an increase under global warming. However, this increase is not solely due to the rise in warm-affinity species, but also linked to the decrease in cold-affinity species. Tropicalization is more pronounced in warmer areas that have experienced greater warming, while deborealization is stronger in areas closer to human populations or with higher thermal diversity in the community.
Article
Geosciences, Multidisciplinary
Lavenia Ratnarajah, Stephane Blain, Philip W. Boyd, Marion Fourquez, Ingrid Obernosterer, Alessandro Tagliabue
Summary: The study examined competition for iron between phytoplankton and bacteria in the iron-limited Southern Ocean. Results show that increased iron and light favor phytoplankton dominance, while increased LDOC and decreased light favor bacterial dominance. Bacteria can outcompete phytoplankton for iron under elevated LDOC conditions.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Limnology
Benjamin S. Twining, Olga Antipova, P. Dreux Chappell, Natalie R. Cohen, Jeremy E. Jacquot, Elizabeth L. Mann, Adrian Marchetti, Daniel C. Ohnemus, Sara Rauschenberg, Alessandro Tagliabue
Summary: Iron quotas of phytoplankton vary significantly across nutrient gradients and geographic locations, influenced by taxonomic and macronutrient controls. Luxury uptake of iron is common in the low-iron Pacific Ocean, particularly among diatoms.
LIMNOLOGY AND OCEANOGRAPHY LETTERS
(2021)
Article
Multidisciplinary Sciences
William B. Homoky, Tim M. Conway, Seth G. John, Daniela Konig, FeiFei Deng, Alessandro Tagliabue, Rachel A. Mills
Summary: This study reveals that lithogenic colloid production is the primary mechanism driving iron supply in sediment porewaters in the South Atlantic, which differs from the prevailing understanding. Iron colloids, closely associated with organic carbon abundance, may form a large exchangeable reservoir of organo-mineral Fe colloids in oxic ocean sediments.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Environmental Sciences
D. Konig, T. M. Conway, M. J. Ellwood, W. B. Homoky, A. Tagliabue
Summary: Iron isotopes in the ocean are crucial in studying the iron cycle, but the complexity of various external sources and fractionation processes can complicate the interpretation of observations. By incorporating iron isotopes into a global ocean biogeochemical model, research finds that distinct external source endmembers and isotopic fractionation are essential for explaining the distribution of dissolved iron isotopes, with the water column's δFe-56(diss) distribution influenced by regional imbalance of remineralization and abiotic removal processes.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Biodiversity Conservation
Juliano Palacios-Abrantes, Thomas L. Frolicher, Gabriel Reygondeau, U. Rashid Sumaila, Alessandro Tagliabue, Colette C. C. Wabnitz, William W. L. Cheung
Summary: Climate change is causing shifts in the distribution of shared fish stocks between neighboring countries, affecting international fisheries governance. By 2030, 23% of transboundary stocks will have shifted, and by the end of the century, projections show that 45% of stocks globally will have shifted. Countries highly dependent on fisheries will be hotspots for these shifts.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Environmental Sciences
Anh Le-Duy Pham, Olivier Aumont, Lavenia Ratnarajah, Alessandro Tagliabue
Summary: Marine free-living bacteria play a crucial role in the cycling of essential biogeochemical elements, and their growth is regulated by nutrient availability, particularly iron. Understanding the factors limiting bacterial growth and their role in the iron cycle is important for understanding biogeochemical cycling.
GLOBAL BIOGEOCHEMICAL CYCLES
(2022)
Article
Geosciences, Multidisciplinary
D. Konig, T. M. Conway, D. S. Hamilton, A. Tagliabue
Summary: This study uses a global ocean biogeochemical model with active Fe isotope cycling to investigate the impact of anthropogenic Fe sources on surface ocean dFe and δFe-56(diss). The results show that the response of dFe, δFe-56(diss), and primary productivity is variable and regulated by the biogeochemical regime, rather than following the footprint of atmospheric deposition. The study also finds that while δFe-56(diss) can trace anthropogenic input, its response is attenuated by fractionation during phytoplankton uptake, but amplified by other isotopically-light Fe sources.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
Nicholas J. Hawco, Alessandro Tagliabue, Benjamin S. Twining
Summary: A new global biogeochemical model has revealed that manganese deficiency limits the maximal growth rates of over half of the phytoplankton in the Southern Ocean. Manganese limitation is most extensive during the austral spring and is influenced by phytoplankton traits and the inhibition of manganese uptake by high zinc concentrations in the Antarctic waters. The expanded range of manganese limitation under increased iron supply during past glacial periods reduces the response of the biological carbon pump.
GLOBAL BIOGEOCHEMICAL CYCLES
(2022)
Article
Biodiversity Conservation
Lewis Wrightson, Nina Yang, Claire Mahaffey, David A. Hutchins, Alessandro Tagliabue
Summary: Marine nitrogen fixation is an important source of new nitrogen in the ocean, but climate change may affect the ecological niche and physiology of nitrogen-fixing organisms. Warming can increase the nitrogen fixation-specific elemental use efficiency (EUE) of diazotrophs, reducing their nutrient requirements. A new model predicts a global decline in nitrogen fixation in the future, but regional responses are influenced by the thermal performance curves and EUE of diazotrophs.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Alessandro Tagliabue, Alastair J. M. Lough, Clement Vic, Vassil Roussenov, Jonathan Gula, Maeve C. Lohan, Joseph A. Resing, Richard G. Williams
Summary: The dispersal of dissolved iron from hydrothermal vents in the Trans-Atlantic-Geotraverse system is mainly controlled by physical processes and occurs predominantly in the colloidal phase. Fine-scale mixing near the seafloor and transport through fracture zones play important roles in the dispersal, leading to predominant westward dispersal away from the Mid-Atlantic ridge at a larger scale, while diapycnal mixing drives northward transport within the ridge axial valley. Coarse resolution ocean models often used to assess ocean iron cycling are not able to accurately reproduce the observed dispersal due to the omission of local topography and mixing.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
P. N. Sedwick, B. M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, T. E. Williams
Summary: Constraining the role of dust deposition in regulating the concentration of iron in surface ocean waters requires understanding the flux of seawater-soluble iron in aerosols and the replacement time of dissolved iron in the euphotic zone. This study estimates these quantities using DFe data from the Bermuda Atlantic Time-series Study region and measurements of iron in aerosols and rain from Bermuda in 2019. The results suggest a seasonal variation in surface DFe concentrations and a mean euphotic-zone residence time of 0.8-1.9 years for DFe with respect to aeolian input.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Multidisciplinary Sciences
Thomas J. Ryan-Keogh, Sandy J. Thomalla, Pedro M. S. Monteiro, Alessandro Tagliabue
Summary: Southern Ocean primary productivity is affected by light and iron limitation, but the factors determining iron availability, accessibility, and demand are uncertain. In this study, we analyzed long-term data collected by Biogeochemical Argo floats and ship-based platforms to examine the effects of iron stress on phytoplankton photophysiology. We observed a significant multidecadal trend of increasing iron stress and declining regional net primary production. This trend is attributed to changes in the Southern Ocean mixed-layer physics and complex biological and chemical feedback, highlighting important ongoing changes in the Southern Ocean carbon cycle.
Article
Multidisciplinary Sciences
Alessandro Tagliabue, Kristen N. N. Buck, Laura E. E. Sofen, Benjamin S. S. Twining, Olivier Aumont, Philip W. W. Boyd, Salvatore Caprara, William B. B. Homoky, Rod Johnson, Daniela Konig, Daniel C. C. Ohnemus, Bettina Sohst, Peter Sedwick
Summary: Iron is important in regulating the ocean carbon cycle, with organic ligands playing a crucial role in stabilizing dissolved iron concentrations. However, the role of authigenic iron phases and the inconsistencies observed in dissolved iron cycling challenge the primary control of ligands. Through a study in the Bermuda Atlantic Time-series Study (BATS) region, it was found that upper-ocean dissolved iron dynamics are decoupled from ligands, indicating the need for a mechanism that allows dissolved iron to escape ligand stabilization and form a reservoir of settling iron particles. When this mechanism was implemented in a global-scale biogeochemical model, it successfully reproduced seasonal iron-cycle dynamics and global datasets where previous models failed.
Article
Ecology
Garrett Sharpe, Liang Zhao, Meredith G. Meyer, Weida Gong, Shannon M. Burns, Allesandro Tagliabue, Kristen N. Buck, Alyson E. Santoro, Jason R. Graff, Adrian Marchetti, Scott Gifford
Summary: Synechococcus, the most abundant cyanobacteria in high latitude regions, plays a significant role in annual marine net primary productivity. However, the uneven sampling of Synechococcus populations across the ocean, particularly in high-latitude, High Nutrient Low Chlorophyll (HNLC) regions, has limited our understanding of their adaptations to iron limitation and their influence on carbon, nitrogen, and iron cycles. This study focuses on Synechococcus populations in the subarctic North Pacific, a well-characterized HNLC region, and reveals their dependence on ammonium and other forms of recycled nitrogen, leading to reduced iron requirements. The findings have important implications for modeling the contribution of cyanobacteria to primary production and carbon export.
ISME COMMUNICATIONS
(2023)