Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes

Unger S, Maguas C, Pereira JS, Aires LM, David TS, Werner C (2010)
Oecologia 163(4): 1043-1057.

Journal Article | Published | English

No fulltext has been uploaded

Author
; ; ; ; ;
Abstract
Combining C flux measurements with information on their isotopic composition can yield a process-based understanding of ecosystem C dynamics. We studied the variations in both respiratory fluxes and their stable C isotopic compositions (delta C-13) for all major components (trees, understory, roots and soil microorganisms) in a Mediterranean oak savannah during a period with increasing drought. We found large drought-induced and diurnal dynamics in isotopic compositions of soil, root and foliage respiration (delta C-13(res)). Soil respiration was the largest contributor to ecosystem respiration (R (eco)), exhibiting a depleted isotopic signature and no marked variations with increasing drought, similar to ecosystem respired delta(CO2)-C-13, providing evidence for a stable C-source and minor influence of recent photosynthate from plants. Short-term and diurnal variations in delta C-13(res) of foliage and roots (up to 8 and 4aEuro degrees, respectively) were in agreement with: (1) recent hypotheses on post-photosynthetic fractionation processes, (2) substrate changes with decreasing assimilation rates in combination with increased respiratory demand, and (3) decreased phosphoenolpyruvate carboxylase activity in drying roots, while altered photosynthetic discrimination was not responsible for the observed changes in delta C-13(res). We applied a flux-based and an isotopic flux-based mass balance, yielding good agreement at the soil scale, while the isotopic mass balance at the ecosystem scale was not conserved. This was mainly caused by uncertainties in Keeling plot intercepts at the ecosystem scale due to small CO2 gradients and large differences in delta C-13(res) of the different component fluxes. Overall, stable isotopes provided valuable new insights into the drought-related variations of ecosystem C dynamics, encouraging future studies but also highlighting the need of improved methodology to disentangle short-term dynamics of isotopic composition of R (eco).
Publishing Year
ISSN
eISSN
PUB-ID

Cite this

Unger S, Maguas C, Pereira JS, Aires LM, David TS, Werner C. Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes. Oecologia. 2010;163(4):1043-1057.
Unger, S., Maguas, C., Pereira, J. S., Aires, L. M., David, T. S., & Werner, C. (2010). Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes. Oecologia, 163(4), 1043-1057.
Unger, S., Maguas, C., Pereira, J. S., Aires, L. M., David, T. S., and Werner, C. (2010). Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes. Oecologia 163, 1043-1057.
Unger, S., et al., 2010. Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes. Oecologia, 163(4), p 1043-1057.
S. Unger, et al., “Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes”, Oecologia, vol. 163, 2010, pp. 1043-1057.
Unger, S., Maguas, C., Pereira, J.S., Aires, L.M., David, T.S., Werner, C.: Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes. Oecologia. 163, 1043-1057 (2010).
Unger, Stephan, Maguas, Cristina, Pereira, Joao S., Aires, Luis M., David, Teresa S., and Werner, Christiane. “Disentangling drought-induced variation in ecosystem and soil respiration using stable carbon isotopes”. Oecologia 163.4 (2010): 1043-1057.
This data publication is cited in the following publications:
This publication cites the following data publications:

8 Citations in Europe PMC

Data provided by Europe PubMed Central.

Malate as a key carbon source of leaf dark-respired CO2 across different environmental conditions in potato plants.
Lehmann MM, Rinne KT, Blessing C, Siegwolf RT, Buchmann N, Werner RA., J. Exp. Bot. 66(19), 2015
PMID: 26139821
Stable oxygen isotope and flux partitioning demonstrates understory of an oak savanna contributes up to half of ecosystem carbon and water exchange.
Dubbert M, Piayda A, Cuntz M, Correia AC, Costa E Silva F, Pereira JS, Werner C., Front Plant Sci 5(), 2014
PMID: 25339970
Minimising methodological biases to improve the accuracy of partitioning soil respiration using natural abundance 13C.
Snell HS, Robinson D, Midwood AJ., Rapid Commun. Mass Spectrom. 28(21), 2014
PMID: 25279748
On the use of phloem sap δ¹³C as an indicator of canopy carbon discrimination.
Rascher KG, Maguas C, Werner C., Tree Physiol. 30(12), 2010
PMID: 21071770

77 References

Data provided by Europe PubMed Central.


LK, Glob Biogeochem Cycles 18(), 2004

JM, Agric For Meteorol 136(), 2006

Export

0 Marked Publications

Open Data PUB

Web of Science

View record in Web of Science®

Sources

PMID: 20217141
PubMed | Europe PMC

Search this title in

Google Scholar