Embedded Files
How do Arctic diazotrophs colonise particles?
Using a very neat chemotaxis assay adapted to study particle colonisation, our PhD student Arthur Coët finds that diazotroph groups selectively colonize organic particles, with niche partitioning that may expand under future warming and enhance nitrogen fixation to support Arctic productivity.
Check out the publication in ISME J!
Mar receives the ASLO Yentsch-Schindler Award
Check the video of the plenary talk here
New publication in Nature Geoscience!
After quite a few years searching for the impact of eddies on N2 fixation, our new paper has been accepted for publication in Nature Geoscience. Led by our former postdoc Cora Hörstman in the frame of the projects FIESTA and DEFINE, onboard the FIGURE cruise funded by Eurofleets, we're now glad to share the great news.
Here, we investigated diazotroph diversity and activity within the Gulf Stream and two associated eddies, a region with intense mesoscale activity known for its significant role in nutrient transport into the North Atlantic Gyre. We show that eddy edges are hotspots for diazotroph activity with potential community connectivity between eddies. Using a long-term mesoscale eddy database, we quantified that N2 fixation rates are up to seventeen times higher within eddies than in ambient waters, overall providing ~21 µmol N m−2 yr−1 to the region. Our results warrant including mesoscale eddies as hotspots for reactive nitrogen input in the oceanic nitrogen cycle.
Thanks to the R/V Atlantic Explorer and the BIOS personnel for their support!
New PhD thesis submitted!
Congrats to Subhadeep Chowdhury for submitting his thesis about N2 fixation in the Indian Ocean
His work has identified the main patterns of N2 fixation and diazotroph biogeography in this largely undersampled ocean, thought to be key in controling global primary productivity
Preparing for New Orleans
Ocean Bridges will be present at Ocean Sciences Meeting in New Orleans!
Arthur will present his new exciting results about particle colonisation by diazotrophs in the Arctic Ocean
Cécile will present results on internal wave/tide interactions driving diazotrophy in New Caledonia
Christian will present single-particle N2 fixation insights from the North Pacific Ocean
stay tuned!
December 2023
Alba defended her PhD with Xelu Morán, Eva Ortega-Retuerta, Christian Tamburini, Tâm Mignot and Isabell Klawonn as jury.
Congrats doctor!
She will be starting a new Postdoc position at Arizona State Univ with Solange Duhamel in January 2024.
July-August 2023
Arthur and Mar just set sail onboard the (amazing) RRS Discovery on the N-ARC cruise.
We'll be looking at particle-associated N2 fixation in the Arctic Ocean (Barents Sea) with marine snow catchers and particle colonization experiments.
We left Southampton (UK) on 9th July and will arrive to TromsøW (Norway) on 13th August.
April 2023... a lot going on lately!
Christian is in California sharing his time between UCSC and Stanford to locate NCDs in particles and analyze them on the nanoSIMS
Elena and Arthur have launched a biweekly coastal monitoring off Marseille
Rémi joined our group and started improving the nifH gene annotation pipeline
Arthur, Subha and Mar went sampling on the Rhône River and the Sainte-Croix Lake for the G-FREDIZ project (collaboration with Edo Bar-Zeev). Freshwater sampling is so different!
meanwhile, Cécile is onboard the R/V Antea in New Caledonia finishing the SWOTALIS cruise!
January 2023
Lots of news in our group! We recently welcomed Christian Furbo (Postdoc), Elena Cerdan (Postdoc) and Cécile Carpaneto (Engineer Lab Manager) in Ocean Bridges :) We finally managed to coincide in space and time and took a group picture.
Molly Moynihan came to visit us at MIO and we had fruitful discussions about reconstructing the nifH database for DADA2.
Mar and Arthur will be joining the N-ARC cruise to the Arctic Ocean onboard the RSS Discovery, leaving from Southampton and arriving to Tromsø between July and August 2023. Exciting news for Ocean Bridges, as this is our first polar work experience!
July 2022
Adventures at sea continue with Cora, Olivier, Stéphanie and Mar onboard the R/V Atlantic Explorer to learn how fine-scales shape N2 fixation in the Gulf Stream. Looking forward to catch this beautiful eddy!
Really happy to share our new publication in ISME J where we find that Trichodesmium can fix N2 while sinking into the cold and dark mesopelagic ocean. Check it out here!
June 2022
Alba and Mar joined the NCD cruise led by Kendra Turk-Kubo and Matt Mills onboard the R/V Kilo Moana for 32 days. We did marine snow catcher, particle succession and DNA-SIP experiments to learn more about how NCDs interact with organic matter in the ocean.
March 2022
Subha and Mar visited Arvind Singh's lab at PRL in Ahmedabad (India) and attended the International Indian Ocean Expedition II science conference.
March 2022
HDR submitted! the defence will take place on Luminy's library l'Hexagone on 5th May. Stay tuned!
February 2022
We're glad to have Marta Sebastián from ICM-CSIC in Barcelona visiting our lab this week! Marta is setting up the BONCAT and nitrogenase antibody staining methods with Arthur and we already spotted some diazotrophically active Vibrio!
Alba is visiting the LIEC lab in Nancy to learn DNA-SIP methods in collaboration with Aurélie Cebron in preparation for the NCD cruise we will be joining in May leaving from Hawaii. Looking forward to seeing what comes out of this!
January 2022
We welcome Arthur Coët, our new Master student who will work on particle colonization by NCDs.
December 2021
Ending the year with great news: our projects DEFINE2 (Diazotroph activity and diversity shaped by fine scale ocean dynamics) and FIESTA (FInE scale dynamicS of diazoTrophs in the oceAn) by LEFE and ANR, respectively! We'll be riding on the Gulf Stream in July 2022 measuring diazotrophy in high-resolution and matching it with fine-scale dynamics.
Mar receives the bronze medal (for early career researchers) from CNRS. Ceremony video available here
September 2021
Mar has just joined the CENTURI Research Committee, an exciting dive into a multidisciplinary and creative community aiming at bridging theoretical, computational and molecular biology to decipher the complexity of living systems.
July 2021
Our Eurofleets+ funded cruise FIGURE is now confirmed for 21-31 July 2022. We will have great colleagues onboard, including Sam Wilson, Julie Robidart, Lola Pérez-Hernández, Borja González-Aguiar, Lidia Carracedo... and many PhD students from all of us. The goal of the cruise is to study diazotrophs at fine scales across the Gulf Stream.
July 2021
We're glad to welcome Angelina Klett and Jacqueline Ümbricht from IOW (Germany). They will stay with us 3 months to participate in the NOTION project summer experiments together with Alba and Emile.
New samples for Subhadeep! our collaborator Maren Voss has provided us samples from a transatlantic transect of a recent cruise onboard the Meteor. Subhadeep will be analyzing nifH and nifD genes on them.
June 2021
Alana Boyer, our intern from Polytech, is making great progress on her project about particle bacterial colonization. This week she embedded particles in resin, cut them in thin slices with a microtome (as thin as 5 µm!) , and visualized them on 3DHISTECH. Check this beautiful images out!
May 2021
Mar will be appointed as an Associate Editor for JGR Biogeosciences starting in June. Challenging task ahead!
We've been at sea! During the PARTY cruise onboard the R/V Téthys II we collected particles from the epi- and mesopelagic to examine microbial colonization by BONCAT. Check the method here!
April 2021
Alba goes to Denmark KU to Lasse Riemann group to acquire experience and learn useful molecular techniques to process DNA and RNA samples from @tongaproject onboard experiments
Alba is looking at the effects of DOP molecules on nifH expression in diazotrophs in the Western Tropical South Pacific
March 2021
Samples from the SWINGS cruise arrived! Thanks to a collaboration with Hugo Berthelot we recently received DNA samples and diazotroph isolates from the Indian Ocean, obtained during the Geotraces SWINGS cruise. Subhadeep will work on them under the projects DINDE and IDEFIX.
Khaled Metwally visits our lab to try sonoporation on diazotroph cultures
January 2021
It's our pleasure to welcome our new group member Subhadeep Chowdhury! Subhadeep starts his PhD thesis on N2 fixation and its seasonal variability in the Indian Ocean in the frame of the project DINDE, endorsed by the International Indian Ocean Expedition II. Due to Covid19 issues, the two cruises Subhadeep was going to attend have been postponed to 2023... but keep it up, French colleagues are picking up samples from him in the southern Indian Ocean in the SWINGS cruise! Meanwhile he's looking for alternative nitrogenases in Indian Ocean samples using the OGA database.
ASLO 2021 will be held online. Check out our session "SS39 The present and future of nitrogen fixation in aquatic systems" chaired together with Sophie Bonnet, Doug Capone, Lasse Riemann and Maren Voss.
More November 2020....
France goes on national lock-down again, but the Ocean Bridgers are allowed to come to work in the lab... (we're the lucky ones!). From left to right on the lower row: Clara, Mar, Alba and Javi, on the back: Jean-Charles.
November 2020
We welcome Jean-Charles Cancel, a new postdoc in the group who will be working on a nanobody immunolabeling approach to detect diazotrophs in high-resolution. He has some new cool ideas as well... ;p
October 2020
We sampled some 400L of seawater from the marine station Endoume (Marseille) and got the NOTION experiments up and running!
but right before that we enjoyed the (probably) last day of diving of the season, together with the Carbon/Dark Ocean colleagues of the lab and a couple biophysicists that wanted to join ;p
September 2020
1st September, today we welcome Clara Ducrocq! Clara is an Bachelor student from University of Versailles. She is mostly interested in forest ecology, but due to Covid travel restrictions ended up doing an internship with an oceanography group :) She's working closely with Alba on getting the NOTION experiments up and running.
and today also, we re-welcome Javier Berdún, who does his thesis between the IOCAG and MIO. Javi will be looking at the adhesion of Trichodesmium colonies in the frame of the project ART.
July 2020
NOTION project tests have started! Alba Filella is working on getting pH sensors right and soon we'll be ready to go. Look at her gorgeous 40 L tanks...
June 2020
Congrats to Louis Conradt for defending his MSc thesis today! Louis found that fine scale dynamics distribute groups of diazotrophs in a different manner. The results are available on this preprint and have been submittted for publication.
May 2020
Really happy to find a great student for a great project! Alba Filella is currently finishing her Masters at GEOMAR and will be soon joining our lab. She will investigate the use of diverse DOM molecules by cyanobacterial and non-cyanobacterial in natural environments such as the North Atlantic and Indian Oceans, as well as in experimental setups with cultured diazotrophs under climate change simulations.
April 2020
Covid forced us to have our NOTION project kick-off meeting online. Great discussions between biogeochemists, molecular biologists and modelers from 4 different countries, all of us eager to understand how climate change will affect diazotrophs in the ocean. Check the project's twitter here
April 2020
Glad to announce that our project DINDE has been endorsed by the International Indian Ocean Expedition II! Check endorsed projects here
February 2020
Exciting talks at the "New Tools and Approaches to Constrain the Marine Nitrogen Cycle: From the Surface to the Sediments" session at Ocean Sciences Meeting 2020! check abstracts here
December 2019
We are glad to announce that we've received funding from the Climate & Biodiversity initiative of the BNP Paribas Foundation! The project NOTION “NitrOgen fixers structuring phyToplankton bIodiversity in the OceaN under climate change” will look at the effect of climate change on marine diazotrophs and how it cascades to phytoplankton diversity in the future ocean. This is a collaborative project with Lasse Riemann (KU, Denmark), Maren Voss (IOW, Germany) and Nicolas Gruber (ETH Zurich, Switzerland).
July 2019
Mar Benavides is the recipient of the 2019 IAPSO Early Career Scientist medal in chemical ocean science. This is awarded in recognition of her development of original strategies, integrating disciplines, to introduce a novel and comprehensive oceanographic approach to nitrogen cycling research.
May 2019
Our recent talk "How does diazotroph derived nitrogen transfer in the planktonic food web?" at the ASLO's Spotlight Publications Session is now available in YouTube, check it out!
The results of our last black carbon experiment in Vietnam has been recently published in Science of the Total Environment.
It was a great pleasure to give a talk at the National Oceanography Centre in Southampton UK!
March 2019
Isabel Baños and Javier Berdún visited us at MIO in March-April 2019. Isabel worked hard to get her thesis manuscripts written up, while Javier learnt 15N-labeling techniques to start his fieldwork in the Canary Islands this summer. We hope to have you back soon guys!
November 2018
We're sampling in Halong Bay!
Halong ("descending dragon" in Vietnamese) is a 1553 km² bay in the norther coast of Vietnam sown with about two-thousand limestone isles, and a UNESCO World Heritage Site.
Halong Bay harbors traditional fisheries and aquaculture settings, but is also subject to intense touristic and commercial marine traffic, wastewater spills and great inputs of black carbon.
In November 2018 we sampled in thisstudied the role of marine microbes in degrading black carbon particles in Halong Bay.
Our colleague Thuoc Van Chu from IMER always saves the day: he's not only our interpreter but also the best connoisseur of Halong Bay.
Xavier Mari investigates the role of black carbon in the marine biological carbon pump. During our experiments in Halong Bay, he sweated hard to sample enough surface microlayer volume!
Google Sites
Report abuse