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Title: On the Covariation of Chlorophyll Fluorescence and Photosynthesis Across Scales
Abstract

Recent advances in remote sensing of solar‐induced chlorophyll fluorescence (SIF) have garnered wide interest from the biogeoscience and Earth system science communities, due to the observed linearity between SIF and gross primary productivity (GPP) at increasing spatiotemporal scales. Three recent studies, Maguire et al., (2020,https://doi.org/10.1029/2020GL087858), He et al. (2020,https://doi.org/10.1029/2020GL087474), and Marrs et al. (2020,https://doi.org/10.1029/2020GL087956) highlight a nonlinear relationship between fluorescence and photochemical yields and show empirical evidence for the decoupling of SIF, stomata, and the carbon reactions of photosynthesis. Such mechanistic studies help advance our understanding of what SIF is and what it is not. We argue that these findings are not necessarily contradictory to the linear SIF‐GPP relationship observed at the satellite scale and provide context for where, when, and why fluorescence and photosynthesis diverge at smaller spatiotemporal scales. Understanding scale dependencies of remote sensing data is crucial for interpreting SIF as a proxy for GPP.

 
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Award ID(s):
1926090 2005574 1926023
NSF-PAR ID:
10375510
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
47
Issue:
23
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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