Linking hyperspectral PRISMA data with ecosystem functional properties at ICOS sites

Selected Ecosystem Functional Properties, calculated from data collected by the flux tower stations of the ICOS network in Europe, were linked to vegetation indices extracted by satellite PRISMA hyperspectral data. Fourteen stations and sixty images were gathered for this preliminary research, in five different ecosystems including various forest types, grasslands, and wetlands. Several pre-processing steps, for both flux and PRISMA data, were needed prior to computation of correlation values and analysis of the fit for the most promising relationships. The results indicate that certain indices are highly correlated with Gross Primary Productivity, Net Ecosystem Exchange, Light Use Efficiency, and Water Use Efficiency, with the first three EFPs obtaining better values. Similar results are obtained also considering only broadleaved forest data. All the relationships resulted being linear or at the second polynomial order. Narrowband indices reporting information from the green to near infrared spectral region resulted the most useful ones. This effort shows the potential of upscaling tower station information to larger extent with PRISMA data, and additional research is planned expanding the dataset to other sites.