Glob. Change Biol. https://doi.org/cq2p (2018).
Measurement of light released during photosynthesis — known as solar-induced fluorescence (SIF) — is a promising way to detect plant photosynthetic activity. Because SIF can be measured from satellites it is an exciting prospect for understanding global-scale patterns of plant productivity, providing a new window on climate–biosphere interactions. Fine-resolution Orbiting Carbon Observatory‐2 (OCO‐2) measurements now provide an opportunity to examine SIF–gross primary production (GPP) relationships at ecosystem scale using flux towers for comparison.
Xing Li from the University of New Hampshire, Durham, and co-workers conduct a global analysis of the relationship between OCO‐2 SIF and flux tower GPP for 64 sites across eight major biomes to investigate how strong the SIF–GPP relationship is for each biome and whether a robust, general relationship can be found.
They detect strong linear (daily timescale) relationships between SIF and GPP measurements for all biomes except evergreen broadleaf forests. These findings support the use of fine-resolution SIF observations for the estimation of terrestrial photosynthesis across a wide variety of biomes. They also identify some of the limitations of this approach for ecosystem functioning and carbon cycle applications.