Can frequent precipitation moderate the impact of drought on peatmoss carbon uptake in northern peatlands?
Article first published online: 1 APR 2014
© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust
Volume 203, Issue 1, pages 70–80, July 2014
How to Cite
Nijp, J. J., Limpens, J., Metselaar, K., van der Zee, S. E. A. T. M., Berendse, F. and Robroek, B. J. M. (2014), Can frequent precipitation moderate the impact of drought on peatmoss carbon uptake in northern peatlands?. New Phytologist, 203: 70–80. doi: 10.1111/nph.12792
- Issue published online: 28 MAY 2014
- Article first published online: 1 APR 2014
- Manuscript Accepted: 3 MAR 2014
- Manuscript Received: 11 DEC 2013
- Schure-Beijerinck-Popping fund
- Dutch Foundation for the Conservation of Irish Bogs
- Division for Earth and Life Sciences (ALW)
- Netherlands Organization for Scientific Research
- Research Innovation Scheme. Grant Number: 863.10.014
- climate change;
- desiccation tolerance;
- moisture stress;
- rain variability;
- Sphagnum physiology;
- water balance
- Northern peatlands represent a large global carbon store that can potentially be destabilized by summer water table drawdown. Precipitation can moderate the negative impacts of water table drawdown by rewetting peatmoss (Sphagnum spp.), the ecosystem's key species. Yet, the frequency of such rewetting required for it to be effective remains unknown. We experimentally assessed the importance of precipitation frequency for Sphagnum water supply and carbon uptake during a stepwise decrease in water tables in a growth chamber.
- CO2 exchange and the water balance were measured for intact cores of three peatmoss species (Sphagnum majus, Sphagnum balticum and Sphagnum fuscum) representative of three hydrologically distinct peatland microhabitats (hollow, lawn and hummock) and expected to differ in their water table–precipitation relationships.
- Precipitation contributed significantly to peatmoss water supply when the water table was deep, demonstrating the importance of precipitation during drought. The ability to exploit transient resources was species-specific; S. fuscum carbon uptake increased linearly with precipitation frequency for deep water tables, whereas carbon uptake by S. balticum and S. majus was depressed at intermediate precipitation frequencies.
- Our results highlight an important role for precipitation in carbon uptake by peatmosses. Yet, the potential to moderate the impact of drought is species-specific and dependent on the temporal distribution of precipitation.