Integrating Solar Induced Fluorescence and the Photochemical Reflectance Index for Estimating Gross Primary Production in a Cornfield

摘要: The utilization of remotely sensed observations for light use efficiency (LUE) and tower-based gross primary production (GPP) estimates was studied in a USDA cornfield. Nadir hyperspectral reflectance measurements were acquired at canopy level during collaborative field campaign conducted four growing seasons. Photochemical Reflectance Index (PRI) solar induced chlorophyll fluorescence (SIF), derived. SIF retrievals accomplished the two telluric atmospheric oxygen absorption features centered 688 nm (O2-B) 760 (O2-A). PRI examined conjunction with GPP LUE determined by flux measurements. All these fluxes, environmental variables, exhibited diurnal as well day-to-day dynamics across Consistent previous studies, shown to be related (r2 = 0.54 logarithm fit), but relationship varied each year. By combining linear regression model, stronger performances estimation obtained. strongest 0.80, RMSE 0.186 mg CO2/m2/s) achieved when using nm. Cross-validation approaches utilized demonstrate robustness consistency performance. This study highlights retrieval method based entirely on remote sensing observations.