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| Titel |
The fate of residual carbon in floodplain sediments, originating from
eroding peatlands |
| VerfasserIn |
Danielle Alderson, Martin Evans, James Rothwell, Stephen Boult, Edward Rhodes |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250123963
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| Publikation (Nr.) |
 EGU/EGU2016-3309.pdf |
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| Zusammenfassung |
| Fluvial systems and their associated sediments have been overlooked as part of global carbon
budgets until recently. In the UK, large stores of organic carbon in peatlands are dynamically
eroding, with the eventual result being ‘off-site’ greenhouse gas emissions, which must be
incorporated into carbon budgets for management strategies. Evans et al. (2013) concluded
peatland fluvial systems are active cyclers of carbon, with 50-90% of particulate organic
carbon (POC) exported from peatlands eventually emitted as CO2. Floodplains,
although commonly regarded as zones of carbon storage, have been identified as
potential hotspots of carbon cycling in the fluvial system with a key process being
decomposition of POC. Only 20% of POC may escape mineralisation on floodplains
within a peatland catchment (Evans et al., 2013), but studying the composition of the
residual carbon has the potential to add to understanding of the drivers of storage
versus mineralisation. In this research we have examined stratigraphic records of
carbon cycling by focusing on organic matter preserved in a floodplain environment
downstream of the Bleaklow Plateau in the Peak District. An OSL date of 640 +/- 90
years BP and a radiocarbon date of 500-310 cal years BP from the sediment cores
collected, together with an assessment of the valley morphology using high resolution
LiDAR DEM’s, indicate potential interaction of post glacial landslide features with
the onset of substantial peat erosion, conditioning the landscape to interrupt the
transport of carbon down the fluvial network. Floodplain cores have been correlated
on the basis of both visual stratigraphy and geochemistry obtained by Itrax core
scanning. This data is supported by targeted gas flux data from boreholes using
a Gasclam. We present a rudimentary carbon budget for the floodplain of study. |
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