The diel imprint of leaf metabolism on the δ13 C signal of soil respiration under control and drought conditions

© 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 192(2011), 4 vom: 01. Dez., Seite 925-938
1. Verfasser: Barthel, Matthias (VerfasserIn)
Weitere Verfasser: Hammerle, Albin, Sturm, Patrick, Baur, Thomas, Gentsch, Lydia, Knohl, Alexander
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2011
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Carbon Isotopes Soil Carbon 7440-44-0
Beschreibung
Zusammenfassung:© 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.
Recent (13) CO(2) canopy pulse chase labeling studies revealed that photosynthesis influences the carbon isotopic composition of soil respired CO(2) (δ(13) C(SR)) even on a diel timescale. However, the driving mechanisms underlying these short-term responses remain unclear, in particular under drought conditions. The gas exchange of CO(2) isotopes of canopy and soil was monitored in drought/nondrought-stressed beech (Fagus sylvatica) saplings after (13) CO(2) canopy pulse labeling. A combined canopy/soil chamber system with gas-tight separated soil and canopy compartments was coupled to a laser spectrometer measuring mixing ratios and isotopic composition of CO(2) in air at high temporal resolution. The measured δ(13) C(SR) signal was then explained and substantiated by a mechanistic carbon allocation model. Leaf metabolism had a strong imprint on diel cycles in control plants, as a result of an alternating substrate supply switching between sugar and transient starch. By contrast, diel cycles in drought-stressed plants were determined by the relative contributions of autotrophic and heterotrophic respiration throughout the day. Drought reduced the speed of the link between photosynthesis and soil respiration by a factor of c. 2.5, depending on the photosynthetic rate. Drought slows the coupling between photosynthesis and soil respiration and alters the underlying mechanism causing diel variations of δ(13) C(SR)
Beschreibung:Date Completed 12.03.2012
Date Revised 20.05.2021
published: Print-Electronic
ErratumIn: New Phytol. 2014 Jun;202(4):1412. - PMID 33892584
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/j.1469-8137.2011.03848.x