Microbial controls on carbon loss from eroding and restored UK blanket peatland

The blanket peatlands of the UK are important terrestrial carbon stores but are uniquely eroded because of impacts of industrial pollution, overgrazing, wildfire and climate change (Evans and Warburton, 2011 and Figure 1). Carbon is lost from eroded peatlands through physical erosion but also in dissolved and gaseous forms because of in situ microbial decomposition of organic matter in peat. Degraded peatlands can shift from carbon sinks to carbon sources. In the last decade there have been significant efforts to restore the degraded peatlands of the British uplands. Although microbial communities have been investigated in the context of restoration (Elliott et al., 2015), there has been little work on microbial function in the context of carbon loss from degraded and restored systems. This project aims to develop understanding of the links between peatland restoration, microbial communities and carbon cycling in upland peatlands.

This PhD will take advantage of a unique catchment experiment in the southern Pennines which has been established as part of a previous project (see http://tinyurl.com/oyh5z7t and Figure 2) in order to investigate the impact of peatland restoration on the microbial processes which drive changes in dissolved and gaseous carbon loss from peatland systems. There will be four main objectives:
1) To investigate the representativeness of the experimental site in terms of its microbial communities.
2) To investigate the impact of the restoration treatments on the size and composition of microbial communities at the catchment scale.
3) To investigate, in an environment which is hydrologically flashy, short term variability in microbial community composition associated with storm events.
4) To investigate microbial composition varying in time and space as a control on carbon losses from the peatland system (in dissolved form in runoff and gaseous losses from the peatland surface).

Techniques:
1) Microbial community composition and activity assessed using DNA and RNA analyses (using high throughput Illumina sequencing platform) and appropriate functional gene determinations.
2) Gaseous carbon flux. Direct chamber based measurements of CO2, CH4 and N2O.
3) Dissolved carbon flux. Fortnightly sampling of waters (assisted by Moors for the Future) and continuous flow measurement from microcatchments.
4) Water table measurement – building on existing dipwell networks.

Project Partners: This project will be undertaken in close collaboration with Moors for the Future. MftF are a partnership of land owners and conservation agencies who have been delivering peatland restoration in the southern Pennines and who were the lead partners in the Making Space for Water project.