A Test of the 'one-point method' for estimating maximum carboxylation capacity from field-measured, light-saturated photosynthesis

Martin G. De Kauwe*, Yan Shih Lin, Ian J. Wright, Belinda E. Medlyn, Kristine Y. Crous, David S. Ellsworth, Vincent Maire, I. Colin Prentice, Owen K. Atkin, Alistair Rogers, Ülo Niinemets, Shawn P. Serbin, Patrick Meir, Johan Uddling, Henrique F. Togashi, Lasse Tarvainen, Lasantha K. Weerasinghe, Bradley J. Evans, F. Yoko Ishida, Tomas F. Domingues

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    105 Citations (Scopus)

    Abstract

    Simulations of photosynthesis by terrestrial biosphere models typically need a specification of the maximum carboxylation rate (Vcmax). Estimating this parameter using A-Ci curves (net photosynthesis, A, vs intercellular CO2 concentration, Ci) is laborious, which limits availability of Vcmax data. However, many multispecies field datasets include net photosynthetic rate at saturating irradiance and at ambient atmospheric CO2 concentration (Asat) measurements, from which Vcmax can be extracted using a 'one-point method'. We used a global dataset of A-Ci curves (564 species from 46 field sites, covering a range of plant functional types) to test the validity of an alternative approach to estimate Vcmax from Asat via this 'one-point method'. If leaf respiration during the day (Rday) is known exactly, Vcmax can be estimated with an r2 value of 0.98 and a root-mean-squared error (RMSE) of 8.19 μmol m-2 s-1. However, Rday typically must be estimated. Estimating Rday as 1.5% of Vcmax, we found that Vcmax could be estimated with an r2 of 0.95 and an RMSE of 17.1 μmol m-2 s-1. The one-point method provides a robust means to expand current databases of field-measured Vcmax, giving new potential to improve vegetation models and quantify the environmental drivers of Vcmax variation.

    Original languageEnglish
    Pages (from-to)1130-1144
    Number of pages15
    JournalNew Phytologist
    Volume210
    Issue number3
    DOIs
    Publication statusPublished - 1 May 2016

    Bibliographical note

    Corrigendum can be found at New Phytologist volume 212(3), p792, http://dx.doi.org/10.1111/nph.14172

    Keywords

    • A-C curve
    • leaf respiration during the day (R)
    • maximum carboxylation rate (V)
    • net photosynthetic rate at saturating irradiance and at ambient atmospheric CO concentration (A)

    Fingerprint

    Dive into the research topics of 'A Test of the 'one-point method' for estimating maximum carboxylation capacity from field-measured, light-saturated photosynthesis'. Together they form a unique fingerprint.

    Cite this