Descripción del proyecto
Identificación del papel de los diazótrofos en el ciclo del carbono
Los microorganismos diazótrofos ayudan a regular la productividad marina del planeta al convertir el nitrógeno y contribuir a los sumideros de carbono. Sin embargo, se desconoce cuánto carbono derivado de los diazótrofos se exporta a las profundidades oceánicas. El proyecto HOPE, financiado con fondos europeos, tiene por objeto averiguarlo, lo que permitirá realizar mejores predicciones del papel del océano en el secuestro de CO2 y la mitigación del cambio climático. Sus investigadores usarán técnicas isotópicas de célula única para examinar esta bomba de carbono procariota a fin de identificar sus características transitorias y estacionales. También emplearán una columna de agua experimental para determinar cómo se agregan, hunden y remineralizan los diazótrofos, mientras que una plataforma de medición autónoma permitirá supervisar cómo los factores ambientales controlan la eficacia de la bomba. Estas actividades proporcionarán nuevas estimaciones mundiales del carbono exportado por los diazótrofos.
Objetivo
Diazotrophs regulate marine productivity in 60% of our oceans by alleviating nitrogen limitation, contributing to carbon (C) sequestration through the N2-primed Prokaryotic C Pump (PCP). Yet we don’t know how much diazotroph-derived organic C (OC) is exported to the deep ocean, which prevents robust predictions of how the ocean contributes to CO2 sequestration and climate change mitigation. This knowledge gap is due to the multiple and complex pathways by which diazotrophs are exported to the deep ocean, which quantification and drivers of variability are impossible to capture with current methods. HOPE will bridge this gap thanks to a new isotopic technique I developed and to a coupling between lab and in situ approaches examining processes occurring at different spatiotemporal scales, and capable of capturing both transient and seasonal features of the PCP. HOPE will: 1.Determine how various diazotrophs aggregate, sink and are remineralized by using an automated experimental water column I designed for this proposal 2.Decipher by which pathways diazotroph-derived OC is exported to the deep ocean thanks to a pioneer approach combining single-cell isotopic analyses, in-depth microbiological characterization of sinking particles and geochemical budgets 3.Investigate how environmental drivers control the whole process, from the surface diazotroph community up to their eventual export to the deep ocean, by deploying a cutting-edge autonomous platform, unique as it performs synoptic measurements both in and below the euphotic zone at high resolution (hourly/daily). In its final stage, HOPE will use the generated data to provide global, spatially resolved estimates of the contribution of diazotrophs to overall OC export. Based on my expertise at the interface between microbial oceanography and geochemistry, HOPE has the potential to deliver a multidisciplinary and ground-breaking knowledge leading to potential scientific-based recommendations to fight climate change.
Ámbito científico
- natural sciencesearth and related environmental sciencesgeochemistry
- social scienceseconomics and businesseconomicsproduction economicsproductivity
- natural sciencesbiological sciencesecologyecosystems
- natural sciencesearth and related environmental sciencesoceanography
- natural sciencesearth and related environmental sciencesatmospheric sciencesclimatologyclimatic changes
Programa(s)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Régimen de financiación
HORIZON-AG - HORIZON Action Grant Budget-BasedInstitución de acogida
13572 Marseille
Francia