Article
Environmental Sciences
Domitille Louchard, Matthias Munnich, Nicolas Gruber
Summary: The high rates of N-2 fixation in the Western Tropical Atlantic Ocean are mainly due to the influx of nutrients from the Amazon River. In this study, a regional model was used to investigate the impact of the Amazon on different factors controlling N-2 fixation. The simulations showed that the Amazon enhances marine N-2 fixation, with most of the enhancement driven by DDAs.
GLOBAL BIOGEOCHEMICAL CYCLES
(2023)
Article
Ecology
Linquan Mu, Jaime B. Palter, Hongjie Wang
Summary: The Amazon River plume has a significant impact on the carbonate chemistry in the western tropical North Atlantic. By conducting sensitivity tests, we found that adding alkalinity through quicklime in the Amazon River watershed can alter carbonate chemistry and reduce carbon dioxide emissions at the river mouth.
Article
Oceanography
M. Gevaudan, F. Durand, J. Jouanno
Summary: In the past three decades, extreme floods in the Amazon basin have had a significant impact on the population and ecosystems of the area. However, their impact on the tropical Atlantic Ocean is still poorly understood. This study uses a coupled ocean-atmosphere model to investigate the effect of interannual variability in river runoff on sea surface salinity and temperature. The results show that while extreme floods can modulate the sea surface salinity, their impact on sea surface temperature is limited.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Multidisciplinary Sciences
Everton Giachini Tosetto, Sigrid Neumann-Leitao, Moacyr Araujo, Djoirka Minto Dimoune, Arnaud Bertrand, Miodeli Nogueira Jr
Summary: This study investigates the impact of the Amazon River freshwater plume on planktonic cnidarians in the Western Atlantic. The results show that the plume shapes marine habitats, creating a highly productive surface layer compressed by a deeper oxygen minimum zone. Planktonic cnidarian assemblages are diverse and abundant within the plume, while dominant species dominate outside the plume. The Amazon River plume is a crucial physical feature that significantly affects the dynamics of habitat structure in the Western Equatorial Atlantic Ocean.
Article
Environmental Sciences
Linquan Mu, Helga do Rosario Gomes, Shannon M. Burns, Joaquim Goes, Victoria J. Coles, Carlos E. Rezende, Fabiano L. Thompson, Rodrigo L. Moura, Benjamin Page, Patricia L. Yager
Summary: The study investigated the partial pressure of carbon dioxide across the Amazon River plume and the surrounding western tropical North Atlantic Ocean, finding the plume to be a net CO2 sink with distinctive seasonal variability. Results emphasize the importance of considering the variable impacts of biological activity, export, and air-sea gas exchange when estimating regional CO2 fluxes.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Environmental Sciences
C. Haeggi, E. C. Hopmans, E. Schefuss, A. O. Sawakuchi, L. T. Schreuder, D. J. Jr Jr Bertassoli, C. M. Chiessi, S. Mulitza, H. O. Sawakuchi, P. A. Baker, S. Schouten
Summary: Research shows that the Amazon River exports negligible amounts of levoglucosan and concentrations in marine sediments are positively correlated to total organic content. Additionally, an estimated small fraction of levoglucosan is exported by the Amazon River each year.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Environmental Sciences
Domitille Louchard, Nicolas Gruber, Matthias Muennich
Summary: The Amazon River significantly alters the biogeochemistry of the Western Tropical Atlantic by enhancing the net primary production, organic carbon export, and atmospheric CO2 uptake through various mechanisms. This study highlights the importance of considering the land-ocean aquatic continuum in Earth System modeling.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Biology
Changling Ding, Chao Wu, Liuyang Li, Laxman Pujari, Guicheng Zhang, Jun Sun
Summary: This study investigated the spatial variation of diazotrophic communities in the South China Sea and Western Pacific Ocean. The dominant diazotrophs were Proteobacteria in the SCS and Cyanobacteria in the WPO. Temperature, dissolved inorganic nitrogen, and dissolved inorganic phosphate were significantly correlated with variations in diazotroph composition.
Article
Multidisciplinary Sciences
Sophie Charvet, Eunsoo Kim, Ajit Subramaniam, Joseph Montoya, Solange Duhamel
Summary: The study found that habitats created by the Amazon river plume have an impact on the formation of small pigmented eukaryote communities, but the diversity of these communities was not strongly affected by habitat types at this time. Small pigmented eukaryote communities showed a random distribution in population abundances across different stations.
SCIENTIFIC REPORTS
(2021)
Article
Environmental Sciences
Dmitry Frey, Alexander Osadchiev
Summary: Satellite altimetry is an efficient tool for detecting dynamic processes in the global ocean, but using this technology alone is not accurate for detecting the Ob-Yenisei plume, requiring validation with in situ measurements.
Article
Multidisciplinary Sciences
Annika Einbock, Emma Burtscher, Claudia Frey, Franz Conen
Summary: We studied the ice-nucleating particles (INPs) in the plumes of the Tocantins and Amazon rivers, which have varying proportions of degraded land. The concentration of INPs active at -15 degrees C (INP-15) was significantly lower in the Tocantins compared to the Amazon and Atlantic surface waters. The differences in heat tolerance suggest that the sources of INPs from the Amazon rainforest vary depending on their location within or below the canopy.
ROYAL SOCIETY OPEN SCIENCE
(2023)
Article
Oceanography
Sarah C. Weber, Natalie Loick-Wilde, Joseph P. Montoya, Melvin Bach, Hai Doan-Nhu, Ajit Subramaniam, Iris Liskow, Lam Nguyen-Ngoc, Dirk Wodarg, Maren Voss
Summary: The study revealed a shift in the nitrogen source for biological production in mesozooplankton across four different habitats, indicating a change from nitrate in near-coastal waters to diazotroph-N inputs in oceanic waters. This shift was accompanied by an increase in trophic position, suggesting a connection between diazotrophy and the efficiency of nitrogen transfer through the marine food web. The high trophic enrichment value of 5.1 parts per thousand suggested a link between ecosystem heterogeneity and the less efficient transfer of mass and energy across trophic levels.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Multidisciplinary Sciences
Everton Giachini Tosetto, Arnaud Bertrand, Sigrid Neumann-Leitao, Miodeli Nogueira Junior
Summary: The study found that in the Western Tropical Atlantic, the Amazon River plume acts as an important biogeographical barrier, influencing the differences in animal communities between the Caribbean Sea and the Tropical Brazil continental shelf. Results showed more species sharing in the northwest direction, while the Amazon River region is a strong barrier for taxa with reduced dispersal capacity.
SCIENTIFIC REPORTS
(2022)
Article
Environmental Sciences
J. Blake Clark, Antonio Mannino
Summary: The physical and biogeochemical properties of the Arctic Ocean are greatly influenced by freshwater input from land and through the Bering Strait. The Yukon River, one of the largest rivers in North America and the Arctic, contributes large quantities of freshwater and terrigenous material to the northern Bering Sea. A three-dimensional hydrodynamic model was used to study the coastal hydrodynamics at the outflow of the river. The study found that a large anticyclonic eddy persisted at the main outflow of the Yukon River and had an impact on water circulation and plume dispersion.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Oceanography
Ye Liu, Jiping Xie, Zhiqiang Liu, Jianping Gan, Jiang Zhu
Summary: The current high-resolution numerical modeling system around Hong Kong has achieved considerable prediction skill for the estuarine-shelf circulation off the Pearl River Estuary without data assimilation. By implementing Ensemble Optimal Interpolation approach to assimilate cruise temperature and salinity profiles, the prediction errors of temperature and salinity have been reduced and salinity stratification in the shelf has been improved. Water exchanges between the estuary and the shelf are better captured through data assimilation, showing advantages in reproducing the distribution of water masses in the study regions.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Review
Microbiology
Rachel A. Foster, Jonathan P. Zehr
ANNUAL REVIEW OF MICROBIOLOGY, VOL 73
(2019)
Review
Microbiology
Mercedes Nieves-Morion, Enrique Flores, Rachel A. Foster
ENVIRONMENTAL MICROBIOLOGY
(2020)
Article
Ecology
Rachel A. Foster, Daniela Tienken, Sten Littmann, Martin J. Whitehouse, Marcel M. M. Kuypers, Angelicque E. White
Summary: N-2 fixation by filamentous cyanobacteria forms important nitrogen sources in the open sea, particularly in symbiosis with diatoms. This study reveals the relationship between host photosynthesis and nitrogen and carbon fixation by symbiotic organisms, as well as the carbon and nitrogen exchange between symbionts and hosts. Additionally, a size-dependent pattern in nitrogen and carbon fixation rates is identified, with larger cells having higher rates, and light dependence is found in N-2 fixation.
Article
Multidisciplinary Sciences
Hannah Laeverenz Schlogelhofer, Francois J. Peaudecerf, Freddy Bunbury, Martin J. Whitehouse, Rachel A. Foster, Alison G. Smith, Ottavio A. Croze
Summary: Microbial communities play a significant role in biogeochemical processes, animal and plant health, and biotechnological purposes. Isotope labelling combined with SIMS analysis can identify nutrient fluxes and substrate utilisation heterogeneity on a single cell level. By combining SIMS experiments with mechanistic modelling, this study reveals otherwise inaccessible nutrient kinetics in microbial interactions, contributing to a better understanding of these dynamics.
Article
Microbiology
Mercedes Nieves-Morion, Enrique Flores, Martin J. Whitehouse, Aurelien Thomen, Rachel A. Foster
Summary: The study investigated single-cell C and N-2 fixation and metabolic dynamics along filaments in the model heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120 using stable isotopes and imaging techniques. The results revealed a substantial variability of metabolic states in wild-type filaments in culture, demonstrating the unpredicted heterogeneity of cellular metabolic activity.
Article
Multidisciplinary Sciences
Juan Jose Pierella Karlusich, Eric Pelletier, Fabien Lombard, Madeline Carsique, Etienne Dvorak, Sebastien Colin, Marc Picheral, Francisco M. Cornejo-Castillo, Silvia G. Acinas, Rainer Pepperkok, Eric Karsenti, Colomban de Vargas, Patrick Wincker, Chris Bowler, Rachel A. Foster
Summary: This study provides an improved global overview of diazotroph abundance, diversity, and distribution by combining a quantitative image analysis pipeline with metagenomic mining using Tara Oceans datasets. Nitrogen fixation by diazotrophs is critical for marine primary production, with larger diazotrophs dominating tropical belts and unicellular cyanobacterial and non-cyanobacterial diazotrophs globally distributed in surface and mesopelagic layers.
NATURE COMMUNICATIONS
(2021)
Correction
Ecology
Rachel A. Foster, Daniela Tienken, Sten Littmann, Martin J. Whitehouse, Marcel M. M. Kuypers, Angelicque E. White
Correction
Ecology
Tom O. Delmont, Juan Jose Pierella Karlusich, Iva Veseli, Jessika Fuessel, A. Murat Eren, Rachel A. Foster, Chris Bowler, Patrick Wincker, Eric Pelletier
Article
Ecology
Tom O. Delmont, Juan Jose Pierella Karlusich, Iva Veseli, Jessika Fuessel, A. Murat Eren, Rachel A. Foster, Chris Bowler, Patrick Wincker, Eric Pelletier
Summary: The study utilized metagenomic data from various oceans to identify new marine diazotrophs, expanding the known diversity of nitrogen fixers in the ocean. These diazotrophs include cyanobacterial and heterotrophic bacterial populations, highlighting their importance in the marine nitrogen balance.
Article
Microbiology
A. Caputo, J. A. A. Nylander, R. A. Foster
FEMS MICROBIOLOGY LETTERS
(2019)
Article
Ecology
Sophie Bonnet, Mathieu Caffin, Hugo Berthelot, Olivier Grosso, Mar Benavides, Sandra Helias-Nunige, Cecile Guieu, Marcus Stenegren, Rachel Ann Foster
Article
Environmental Sciences
Andrea Caputo, Marcus Stenegren, Massimo C. Pernice, Rachel A. Foster
FRONTIERS IN MARINE SCIENCE
(2018)
Article
Ecology
Marcus Stenegren, Andrea Caputo, Carlo Berg, Sophie Bonnet, Rachel A. Foster
Article
Ecology
Mathieu Caffin, Thierry Moutin, Rachel Ann Foster, Pascale Bouruet-Aubertot, Andrea Michelangelo Doglioli, Hugo Berthelot, Cecile Guieu, Olivier Grosso, Sandra Helias-Nunige, Nathalie Leblond, Audrey Gimenez, Anne Alexandra Petrenko, Alain de Verneil, Sophie Bonnet
Article
Ecology
Dina Spungin, Natalia Belkin, Rachel A. Foster, Marcus Stenegren, Andrea Caputo, Mireille Pujo-Pay, Nathalie Leblond, Cecile Dupouy, Sophie Bonnet, Ilana Berman-Frank