Fluvial carbon flux from headwater peatland streams: significance of particulate carbon flux
Article first published online: 9 MAY 2012
Copyright © 2012 John Wiley & Sons, Ltd.
Earth Surface Processes and Landforms
Volume 37, Issue 11, pages 1203–1212, 15 September 2012
How to Cite
Pawson, R. R., Evans, M. G. and Allott, T. E. H. A. (2012), Fluvial carbon flux from headwater peatland streams: significance of particulate carbon flux. Earth Surf. Process. Landforms, 37: 1203–1212. doi: 10.1002/esp.3257
- Issue published online: 6 SEP 2012
- Article first published online: 9 MAY 2012
- Accepted manuscript online: 26 APR 2012 12:58AM EST
- Manuscript Accepted: 29 MAR 2012
- Manuscript Revised: 22 MAR 2012
- Manuscript Received: 12 APR 2011
- fluvial carbon flux
The extensive blanket peatlands of the UK uplands account for almost half of total national terrestrial carbon storage. However, much of the blanket peat is severely eroded so that the contemporary role of the peatland system in carbon sequestration is compromised by losses of organic carbon in dissolved (DOC) and particulate (POC) form in the fluvial system. This paper presents the first detailed assessment of dissolved and organic carbon losses from a severely eroded headwater peatland (River Ashop, South Pennines, UK). Total annual fluvial organic carbon losses range from 29–106 Mg C km,-2 decreasing from the headwaters to the main catchment outlet. In contrast to less eroded systems fluvial organic carbon flux is dominated by POC. POC:DOC ratios decrease from values of 4 in the headwaters to close to unity at the catchment outlet. These results demonstrate the importance of eroding headwater sites as sources of POC to the fluvial system. Comparison with a range of catchment characteristics reveals that drainage density is the best predictor of POC:DOC but there is scatter in the relation in the headwaters. Steep declines in specific POC yield from headwater catchments are consistent with storage of POC within the fluvial system. Key to the significance of fluvial carbon flux in greenhouse gas budgets is understanding the fate of fluvial carbon. Further work on the fate of POC and the role of floodplains in fluvial carbon cycling is urgently required. Copyright © 2012 John Wiley & Sons, Ltd.