Modification of a gas exchange system to measure active and passive chlorophyll fluorescence simultaneously under field conditions
| Autor: | Eliot W Meeker, Mina Momayyezi, Andrew J. McElrone, Troy S. Magney, Nicolas Bambach |
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| Přispěvatelé: | Yang, Xi |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
photosynthesis 010504 meteorology & atmospheric sciences Field (physics) Spectrometer SIF Photosynthesis system Analytical chemistry Measure (physics) Plant Biology Plant Science Biology Photosynthesis 01 natural sciences Fluorescence leaf-level Special Issue: Solar-Induced Fluorescence: From the Leaf to Beyond the Canopy Fluorometer LI-6800 Chlorophyll fluorescence 010606 plant biology & botany 0105 earth and related environmental sciences |
| Zdroj: | AoB Plants AoB PLANTS, vol 13, iss 1 |
| Popis: | Solar-induced fluorescence (SIF) is a promising tool to estimate photosynthesis across scales; however, there has been limited research done at the leaf level to investigate the relationship between SIF and photosynthesis. To help bridge this gap, a LI-COR LI-6800 gas exchange instrument was modified with a visible-near-infrared (VIS-NIR) spectrometer to measure active and passive fluorescence simultaneously. The system was adapted by drilling a hole into the bottom plate of the leaf chamber and inserting a fibre-optic to measure passive steady-state fluorescence (Ft,λ, analogous to SIF) from the abaxial surface of a leaf. This new modification can concurrently measure gas exchange, passive fluorescence and active fluorescence over the same leaf area and will allow researchers to measure leaf-level Ft,λ in the field to validate tower-based and satellite measurements. To test the modified instrument, measurements were performed on leaves of well-watered and water-stressed walnut plants at three light levels and a constant air temperature. Measurements on these same plants were also conducted using a similarly modified Walz GFS-3000 gas exchange instrument to compare results. We found a positive linear correlation between Ft,λ measurements from the modified LI-6800 and GFS-3000 instruments. We also report a positive linear relationship between Ft,λ and normalized steady-state chlorophyll fluorescence (Ft/Fo) from the pulse-amplitude modulation (PAM) fluorometer of the LI-6800 system. Accordingly, this modification will inform the link between spectrally resolved Ft,λ and gas exchange—leading to improved interpretation of how remotely sensed SIF tracks changes in the light reactions of photosynthesis. |
| Databáze: | OpenAIRE |
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