Caroline Lory
A5053816678- Marine and coastal ecosystems
- Marine Biology and Ecology Research
- Microbial Community Ecology and Physiology
- Oceanographic and Atmospheric Processes
- Geochemistry and Elemental Analysis
- Isotope Analysis in Ecology
Institut de Recherche pour le Développement
2022-2023
Institut Méditerranéen d’Océanologie
2023
Université de Toulon
2022-2023
Centre National de la Recherche Scientifique
2022-2023
Aix-Marseille Université
2022-2023
Abstract. Marine diazotrophs convert dinitrogen (N2) gas into bioavailable nitrogen (N), supporting life in the global ocean. In 2012, first version of oceanic diazotroph database (version 1) was published. Here, we present an updated 2), significantly increasing number situ diazotrophic measurements from 13 565 to 55 286. Data points for N2 fixation rates, cell abundance, and nifH gene copy abundance have increased by 184 %, 86 809 respectively. Version 2 includes two new data sheets...
Iron is an essential nutrient that regulates productivity in ~30% of the ocean. Compared with deep (>2000 meter) hydrothermal activity at mid-ocean ridges provide iron to ocean's interior, shallow (<500 fluids are likely influence surface's ecosystem. However, their effect unknown. In this work, we show emitted along Tonga volcanic arc (South Pacific) have a substantial impact on concentrations photic layer through vertical diffusion. This enrichment stimulates biological activity, resulting...
Diazotrophs are often limited by iron (Fe) availability in the oligotrophic ocean. The Western Tropical South Pacific (WTSP) ocean has been suggested as an intense N2 fixation area due to Fe fertilizations through shallow hydrothermal activity. Yet, demand of diazotrophs their natural habitat, where they cohabit with other microbial organisms also requiring Fe, remains unknown. Here we develop and apply a method consisting coupling 55Fe uptake experiments cell-sorting flow cytometry, provide...
In the Western Tropical South Pacific (WTSP) Ocean, a hotspot of dinitrogen fixation has been identified. The survival diazotrophs depends, among others, on availability dissolved iron (DFe) largely originating, as recently revealed, from shallow hydrothermal sources located along Tonga-Kermadec arc that fertilize Lau Basin with this element. On opposite, these fluids, released directly close to photic layer, can introduce numerous trace metals at concentrations be toxic surface communities....