Descrizione del progetto
Studiare il fitoplancton per prepararsi ai cambiamenti climatici
Il fitoplancton marino fornisce una prospettiva fondamentale sui cicli globali del carbonio e sui cambiamenti climatici. Riconoscendone l’importanza, ulteriori ricerche sul suo funzionamento potrebbero fornire strumenti per prevedere gli effetti dei cambiamenti climatici. Il progetto PHY-GO, finanziato dall’UE, si avvarrà del dispiego a livello globale di galleggianti di profilazione autonomi dotati di sensori biogeochimici per acquisire nuove informazioni approfondite relative ai processi e alla distribuzione del fitoplancton. Il progetto studierà la struttura delle comunità di fitoplancton e la confronterà con i segnali bio-ottici rilevati dai galleggianti. Integrando innovativi metodi di citometria a flusso e precise valutazioni bio-ottiche, il progetto svilupperà e applicherà nuovi dati e tecniche alla propria ricerca.
Obiettivo
Marine phytoplankton are a primary vector in the transport of carbon dioxide from the atmosphere to the ocean interior via the biological carbon pump. The magnitude and efficiency of this flux hinges on phytoplankton community structure—the relative abundance of different phytoplankton groups present within a given water mass. Therefore, accurate estimates of phytoplankton community structure are crucial for understanding global carbon cycles and for anticipating the impact of global climate change. Phytoplankton distributions within the global ocean are typically inferred from bio-optical proxies reflecting phytoplankton physiology (e.g. chlorophyll fluorescence) or concentrations of particulate carbon (e.g. attenuation coefficients or optical backscatter coefficients). The deployment of biogeochemical Argo (BGC-Argo) autonomous profiling floats is transforming the global coverage of these measurements, providing new insight into connections between phytoplankton distributions and export processes. However, few studies have evaluated relationships between bio-optical proxies as measured by BGC-Argo floats and direct measurements of phytoplankton community structure, and none have performed an intercomparison of these relationships across different ocean basins. Therefore, I propose to 1) utilize a combination of novel and existing flow cytometry methods to estimate group-specific phytoplankton biomass across four disparate ocean provinces, 2) evaluate the bio-optical proxies that best predict group-specific phytoplankton biomass within each province, 3) leverage relationships identified in objective 2 to develop a novel transfer function for estimating phytoplankton biomass based on bio-optical proxies alone, and 4) apply this function to existing BGC-Argo data to quantify the importance of variability in phytoplankton community structure to carbon export to the mesopelagic zone, as compared to other mechanisms.
Campo scientifico
Programma(i)
- HORIZON.1.2 - Marie Skłodowska-Curie Actions (MSCA) Main Programme
Meccanismo di finanziamento
MSCA-PF - MSCA-PFCoordinatore
75006 Paris
Francia