CIFRes
Carbon Isotope Fractionation during RESpiration: Mechanisms and environmental drivers
Context
Global warming will change precipitation patterns leading to an increase of frequency and magnitude of drought events. This deficit water supply will effect carbon uptake (photosynthesis) and carbon loss (respiration) by plants in terrestrial ecosystems. Measurement of net ecosystem exchange of CO2 by eddy-covariance techniques does not allow to address assimilation and respiration fluxes separately. Partitioning and quantification of the two opposite carbon dioxide fluxes at the ecosystem scale by the use of stable isotopes is complicated (among others) by the reported variability of δ13C of respired CO2 (CO2Res). In this SNF-funded project, we will examine the metabolic system behind the carbon isotope fractionation during respiration.
Objectives
Within CIFRes, we plan to:
- identify the impacts of environmental drivers on the carbon isotopic signature of CO2Res.
- determine the mechanisms and processes influencing the carbon isotopic signature of CO2Res.
- obtain insight into the processes behind isotope fractionation during respiration, thereby possibly allowing to distinguish between the impact of isotope effects on respirative enzymes and the use of different substrates to gain CO2Res.
Publications
Lehmann MM, Ghiasi S, George GM, Cormier M-A, Gessler A, Saurer M, Werner RA (2019) Influence of starch deficiency on photosynthetic and post-photosynthetic carbon isotope fractionations. Journal of Experimental Botany 70: 1829-1841 doi: external page 10.1093/jxb/erz045
Lehmann MM, Wegener F, Werner RA, Werner C (2016) Diel variations in carbon isotopic composition and concentration of organic acids and their impact on plant dark respiration in different species. Plant Biology 18 776–784 external page doi: 10.1111/plb.12464
Lehmann MM, Wegener F, Barthel M, Maurino V, Siegwolf RTW, Buchmann N, Werner C, Werner RA (2016) Metabolic Fate of the Carboxyl Groups of Malate and Pyruvate and their Influence on δ13C of Leaf-Respired CO2 during Light Enhanced Dark Respiration. Frontiers in Plant Science 7. external page doi: org/10.3389/fpls.2016.00739
Ghashghaie J, Badeck FW, Girardin C, Sketriené D, Lamothe-Sibold M, Werner RA (2015). Changes in δ13C of dark respired CO2 and organic matter of different organs during early ontogeny in peanut plants. Isotopes in Environmental and Health Studies 51: 93-108 doi:external page 10.1080/10256016.2015.1011635
Lehmann MM, Rinne KT, Blessing C, Siegwolf RTW, Buchmann N, Werner RA (2015) Malate as main carbon source of leaf dark-respired CO2 across different environmental conditions in potato plants. Journal of Experimental Botany 66: 5769-5781 doi:external page 10.1093/jxb/erv279
Schmidt H-L, Robins RJ, Werner RA (2015) Multi-factorial in vivo stable isotope fractionation: causes, correlations, consequences and applications. Isotopes in Environmental and Health Studies 51: 155-199 doi:external page 10.1080/10256016.2015.1014355
Werner AW, Buchmann N, Siegwolf RTW, Kornexl BE, Gessler A (2011) Metabolic fluxes, carbon isotope fractionation and respiration – lessons to be learned from biochemistry. New Phytologist 191: 10-15