Descrizione del progetto
Mappare il ruolo dei diazotrofi nel ciclo del carbonio
I microrganismi diazotrofi aiutano a regolare la produttività marina a livello globale convertendo l’azoto e contribuendo ai pozzi di carbonio, ma ci è ignota la quantità di carbonio derivato dai diazotrofi esportata nell’oceano profondo. Il progetto HOPE, finanziato dall’UE, cerca di scoprire proprio questo, consentendo di formulare previsioni migliori circa il ruolo dell’oceano nel sequestro di CO2 e nella mitigazione dei cambiamenti climatici. Avvalendosi di tecniche isotopiche a singola cellula, i ricercatori esamineranno questa pompa di carbonio procariotica al fine di mapparne le caratteristiche transitorie e stagionali. Una colonna d’acqua sperimentale consentirà inoltre ai ricercatori di determinare il modo in cui i diazotrofi si aggregano, assorbono e vengono rimineralizzati, mentre una piattaforma di misurazione autonoma monitorerà il modo in cui i fattori ambientali controllano l’efficienza della pompa. Ciò condurrà a nuove stime globali per il carbonio esportato mediante diazotrofi.
Obiettivo
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.
Campo scientifico
- 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
Programma(i)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Argomento(i)
Meccanismo di finanziamento
HORIZON-AG - HORIZON Action Grant Budget-BasedIstituzione ospitante
13572 Marseille
Francia