Assessing photosynthetic light-use efficiency using a solar-induced chlorophyll fluorescence and photochemical reflectance index

作者：Liu Liangyun; Zhang Yongjiang; Jiao Quanjun; Peng Dailiang

来源：International Journal of Remote Sensing, 2013, 34(12): 4264-4280.

DOI：10.1080/01431161.2013.775533

Photosynthetic light-use efficiency (LUE) is an important indicator of plant photosynthesis, but assessment by remote sensing needs to be further explored. In this study, two protective mechanisms for photosynthesis, chlorophyll fluorescence (ChlF) and heat dissipation in the deep oxidation state of the xanthophyll cycle, were explored to estimate photosynthetic LUE from canopy radiance spectra. Four independent experiments were carried out on summer maize (C4 plant) on 5 July 2008, and winter wheat (C3 plant) on 18 April 2008, 16 April 2010, and 13 May 2010, by synchronously measuring daily canopy radiance spectra and photosynthetic LUE. The competitive relationship between ChlF and photochemical yield made it possible to estimate photosynthetic LUE. LUEChlF models were developed for ChlF at 688 nm (R 2=0.72) and 760 nm (R 2=0.59) based on the experimental data from 13 May 2010 at the Guantao flux site. The LUEChlF models were validated by three independent experiments, and the results showed that the LUEChlF relationship was weakened, possibly by variation in species, canopy density, and environmental conditions. As an easy, rapid, non-intrusive method, a photochemical reflectance index (PRI) provides an instantaneous assessment of dynamic photosynthetic LUE. The significant negative relationship between non-photochemical quenching and PRI was confirmed. Although there was a significantly positive relationship between LUE and PRI in all four independent experiments, this was evidently weakened by the canopy and environmental conditions. Difference in PRI (PRI) from the minimum reference PRI around noontime can largely eliminate interference factors. The LUEPRI model was developed based on experimental data from 13 May 2010 at the Guantao flux site (with an R 2 value of 0.85), and validated by the three other independent experiments. The validation result indicated that different species can markedly affect the precision of the PRI difference method.

• 出版日期2013-6-20
• 单位河北农业大学; 中国科学院对地观测与数字地球科学中心