Abstract
In photosynthesis models following the Farquhar formulation, the maximum carboxylation rate Vcmax is the key parameter. Remote-sensing indicators, such as reflectance ρ and Chl fluorescence (ChlF), have been proven as valuable estimators of photosynthetic capacity and can be used as a constraint to Vcmax estimation. We present a methodology to retrieve Vcmax from leaf ρ and ChlF by coupling a radiative transfer model, Fluspect, to a model for photosynthesis. We test its performance against a unique dataset, with combined leaf spectral, gas exchange and pulse-amplitude-modulated measurements. Our results show that the method can estimate the magnitude of Vcmax estimated from the far-red peak of ChlF and green ρ or transmittance τ, with values of root-mean-square error below 10 μmol CO2 m−2 s−1. At the leaf level, the method could be used for detection of plant stress and tested against more extensive datasets. With a similar scheme devised for the higher spatial scales, such models could provide a comprehensive method to estimate the actual photosynthetic capacity of vegetation.
Original language | English |
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Pages (from-to) | 487-500 |
Number of pages | 14 |
Journal | New Phytologist |
Volume | 223 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Jul 2019 |
Keywords
- Fluspect
- leaf Chl fluorescence
- photosynthesis
- reflectance
- Soil–Canopy Observation of Photosynthesis and Energy balance (SCOPE)
- V