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.
Veröffentlicht in: | The New phytologist. - 1979. - 192(2011), 4 vom: 01. Dez., Seite 925-938 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , , , , |
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 |
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 |