Danielle Marie Alderson
- MSc Environment and Climate Change (Distinction), University of Liverpool - 2013
- BSc Geography (First Class Honours), University of Liverpool - 2012
Carbon processing and storage in upland floodplain and reservoir sediments: A combined biogeochemical and geomorphological approach.
Inland waters and their related sediment systems are now being recognized as active cyclers of carbon, disproportionate to the area they occupy in the landscape. However, current research does not fully address the processes and mechanisms that allow these systems to actively cycle carbon. Global carbon budgets are increasingly recognising the importance of, and including peatlands in models. There is a strong link between peatlands and inland waters in the UK, as some peatlands are dynamically eroding, particularly in the south Pennines, with the eventual result being ‘off-site’ greenhouse gas emissions, which must be incorporated into carbon budgets for management and restoration strategies.
A recent DEFRA project concluded fluvial systems are active cyclers of carbon, with 50-90% of POC exported from peatlands eventually emitted as CO2. Although the CO2 released within upland streams does not occur in-situ (i.e within the peatland itself), failure to address these areas may overestimate the terrestrial system as a carbon sink when calculating peatland carbon budgets. Equally, the carbon buried in floodplains, lakes and reservoirs downstream of peatlands needs to be addressed in terms of its origin to be appropriately incorporated in carbon budgets. Thus, arguably research should focus on the processes which do not lead to the ‘default’ fate of carbon mineralisation; those that result in long term sediment burial in floodplains, lakes and reservoirs.
Floodplains, although commonly regarded as zones of carbon storage, have been identified as potential hotspots of carbon cycling in the fluvial system. A key process is decomposition of particulate carbon. Decomposition is known to involve mass loss with selective transformation of labile compounds such as polysaccharides, and preferential preservation of more resistant compounds (refractory aromatics or aliphatics). Several decomposition proxies including FTIR band intensities, hydrogen indices and C/N ratios, correlated with molecular structure determinations using pyrolysis GC-MS have been used successfully in peat cores to disentangle changes due to decomposition and those that are related to vegetation variation. The aim of this research is to determine whether the same techniques can be applied to arguably more complex systems such as floodplains and reservoirs, to examine stratigraphic records of carbon cycling.
This research will take place in the sediment systems downstream of Bleaklow Plateau and Kinder Scout, areas which are severely degrading and have been the focus of intensive research at the University of Manchester.
- Alluvial, lacustrine and reservoir sediment records of environmental change
- Organic biogeochemistry
- Peatland erosion
- Upland geomorphology
- Boyle, J. F., Chiverrell, R. C., Davies, H. and Alderson, D. M. (2014). An approach to modelling the impact of pre-historic farming on Holocene landscape phosphorus dynamics. The Holocene.
- Recipient of the University of Manchester Research Scholar Award in the School of Environment, Education and Development, enabling this PhD to be funded;
- Recipient of the Eric Hardy memorial prize; awarded to an undergraduate or postgraduate student at the University of Liverpool for excellence in an investigative project in North West England or North Wales;
- Recipient of the undergraduate Humboldt prize in Geography; for the candidate who shows the greatest merit.