PhD Studentship: Determining the Potential of Peatland Pestoration for Carbon Sequestration and Climate Change Mitigation

IMPORTANT:  This Advertiser has requested that applicants MUST be National Residents / Valid Work Permit-holders.  Other applicants need not apply.

 

We are inviting applications for this PhD studentship to commence October 2011. The studentship will cover UK/EU tuition fees plus an annual stipend of £13,590pa for three years. This project is one of a number that are in competition for funding. Studentships will be awarded on the basis of merit.

PROJECT SUMMARY

Carbon dioxide emissions from human activity are continuing to rise. To reduce the potential for damaging climate change during the 21^st century, a range of mitigation strategies must be considered. Terrestrial ecosystems currently absorb about one third of the anthropogenic carbon dioxide released to the atmosphere each year. In the UK, undisturbed peatlands absorb 0.4 to 0.7 tonnes of carbon per hectare per year. It is the water-logged nature of these peat soils which reduces the rate at which oxygen penetrates into the peat profile and which slows decomposition allowing organic matter to accumulate. However, historical drainage in the UK uplands has lowered water tables in many areas allowing oxygen to penetrate deeper into peats. Decomposition rates have increased and as a result large areas of peatland are believed to be releasing carbon dioxide to the atmosphere.  This PhD will address the key question of whether blocking historical drains can allow peatlands to recover, and whether restoration can promote a return to carbon sequestration. This studentship project will combine remote sensing and geospatial modelling, with spatially distributed measurements of gaseous flux dynamics to determine the impacts of restoration on the carbon balance of peatlands in Exmoor and Dartmoor National Parks. These measurements will be linked to detailed hydrological monitoring already ongoing at the field sites, within the wider “Mires-on-the-moors” project (current work here is led by Dr Brazier and Dr Anderson). The work undertaken by the successful PhD applicant will contribute to a broader quantitative understanding of the gaseous carbon budget of upland peatlands, pre- and post-restoration. This will permit consideration of appropriate policy recommendations for promoting carbon uptake and climate change mitigation.

METHODS AND APPROACHES

Upland peatlands are extremely heterogeneous environments with the balance between carbon uptake and release varying with changes in topography and plant species type over relatively short spatial length scales. Remote sensing data available to the applicant will include recent airborne LiDAR and thermal imaging data, acquired by the commercial sponsors of the project in 2010. Additionally, a very fine spatial resolution dataset has been acquired in early 2011 from a terrestrial laser scanner at two instrumented test sites on Exmoor. These spatial datasets will be used to provide a spatially distributed assessment of vegetation structure, topography, and the hydrological status of different areas. Elements of the remote sensing approach are novel (for example application of terrestrial laser scanning or ‘cloud-scanning’ to this question) allowing the student to be involved in methodological development. Initial efforts in processing the remote sensing data will focus on areas where gas flux and hydrological measurements are concentrated. Repeated measurements of the relationship between net ecosystem carbon dioxide exchange and light intensity, temperature, soil moisture and water table depth in the different plant communities, will be used to determine key parameters allowing annual rates of carbon uptake or release to be calculated at these sites. These rates will be related to the factors including water table depth and remotely sensed variables. Extensive measurement of the impacts of restoration on the hydrology of the ecosystems will be made, and the gas flux measurements will allow the relative impacts on plant growth and peat decomposition to be quantified. Ultimately net carbon fluxes from different areas, pre- and post-restoration, will be calculated and the effects of restoration on the carbon balance quantified. The detailed knowledge generated on the environmental control of carbon fluxes, coupled with the remote sensing data, will allow findings to be extrapolated to other areas where environmental monitoring is ongoing and to allow for a full consideration of a range of hypothetical restoration scenarios.

The first year of PhD study will include mandatory training and development through attending skills courses provided by the University of Exeter; and extensive reading and review of the subject area. The successful applicant will also be required to undertake extensive fieldwork in the first year, to familiarise themselves with the experimental field plots and to install gas flux monitoring equipment. Preliminary analysis of the remote sensing datasets will also be required. Subsequent research in the following years will seek to combine the field-based observations with data from laboratory analyses (undertaken in Geography’s Sediment Research Facility), and with data derived from novel spatial data acquisition techniques such as terrestrial laser scanning (cloud scanning) and LiDAR-based remote sensing. The science will be cross-disciplinary and will answer the critical question of whether enhancement of moorland-scale carbon sequestration is possible through peatland restoration.

SUPERVISION AND RESEARCH SUPPORT

The proposed PhD project draws upon the emerging research strands of three staff who work across the Streatham and Cornwall campuses in Geography; Anderson, Hartley and Brazier. Each staff member has a proven track-record in their areas of expertise, and this project will provide the opportunity to build a strong collaboration enhancing the ability of the Landscape and Ecosystem Dynamics (ExLED) Research Group. The research builds on existing NERC-funded science through Anderson’s NERC-funded project on “remote sensing of peatland responses to hydrological change” project (NE/F000421/1), Hartley’s NERC-funded project on the response of soil organic matter decomposition to global change (NE/H022333/1), and Brazier/Anderson’s NERC-funded Knowledge Transfer Partnership with South West Water to build capacity and extend the capability of this research group.

The successful applicant will be based at the Streatham Campus in Exeter during the first phase of the project, so as to enable them to capitalise on the knowledge of the existing “mires” research group based there. However the project will be “cross-campus” in that it will draw upon the expertise of supervisors at both the Streatham and Cornwall campuses. The student will be required to spend some time at both campuses during the course of the PhD project and will receive support in the following ways:

·         office accommodation with other PGR students at the Streatham Campus, Exeter including computer (including software) and printing facilities as well as state of the art library and access to up to date journals;

·         hot desk provision at the Cornwall Campus, near Falmouth to allow the applicant to work closely with Anderson on remote sensing analysis;

·         travel funds to allow for cross-campus working and to permit regular participation in field work activities on Dartmoor and Exmoor national parks;

·         provision of University training courses on a range of subjects;

·         regular meetings with the supervisory team across both campuses;

·         the opportunity to connect with a well-established project in which a series of experimental catchments are already established;

·         participation in, and contribution to the research environment of Geography at the University of Exeter (including research seminars);

·         through partnership with South West Water and the National Parks authority, the student will have access to a range of remote sensing datasets covering the spatial extent of both Dartmoor and Exmoor National Parks. A further research “mentor” will be accessible to the student through this partnership – Dr Dave Smith is involved with the project and has a wealth of relevant experiment with practical moorland restoration techniques;

·         access to a network of Exeter-based researchers working on the broader “mires on the moor” project, including Dr Emilie Grand-Clement, and Mr David Luscombe (PhD student);

·         access to high performance computing and associated support;

·         once underway, the project has an excellent chance of securing additional funding for complementary work, including ¹⁴C analysis of gaseous and aqueous carbon fluxes (Hartley and Brazier have had success in applying for NERC Radiocarbon Facility support).

PROJECT IMPACT

The project will have a strong societal impact in terms of the benefits to the South West Water sponsor (and their customers) and the region as a whole. The results will also impact upon upland policy formulation in the UK, feeding directly to Defra via Brazier’s position as advisor to both the soils and water quality teams in Noble House and his involvement in the Defra-funded Flood Demonstration Catchments Project. We anticipate that the research will also produce a series of internationally recognised journal papers. As a guide, we suggest the following provisional papers could arise as a result of the research. We would happily encourage the successful applicant to complete their PhD “by publication”.

• [PhD student], Hartley, I., Anderson, K., Brazier, R.E. Quantifying the effect of peatland restoration on rates of net carbon uptake, plant growth and organic matter decomposition. Target journal: Biogeochemistry.

• [PhD student], Hartley, I., Anderson, K., Brazier, R.E. Quantifying the effect of restoration on the age of carbon being released from two contrasting peatlands. Target journal: Global Change Biology.

• [PhD student], Anderson, K., Hartley, I., Brazier, R.E. Assessing the impact of peatland restoration on water table depths using novel remote sensing approaches. Target journal: Hydrological Processes.

• [PhD student], Anderson, K., Hartley, I., Brazier, R.E. Landscape-scale spatial modelling of vegetation structure, thermal characteristics and near surface moisture content of an upland peatland using remote sensing data. Target journal: Remote Sensing of Environment orLandscape Ecology.

• [PhD student], Anderson, K., Hartley, I., Brazier, R.E. Evaluating gaseous carbon budgets at moorland scales under restoration and climate change scenarios. Target journal: Nature Geoscience orGlobal Biogeochemical Cycles.

SUGGESTED READING

• Garnett, M.H., Hartley, I.P.(2010). A passive sampling method for radiocarbon analysis of atmospheric CO2 using molecular sieve. Atmospheric Environment, 44(7), 877-883.

• Hartley, I.P., Ineson, P.(2008). Substrate quality and the temperature sensitivity of soil organic matter decomposition. Soil Biology and Biochemistry, 40(7), 1567-1574.

• Anderson, K., Bennie, J., Wetherelt, A.(2010). Laser scanning of fine scale pattern along a hydrological gradient in a peatland ecosystem. Landscape Ecology, 25(3), 477-492

• Anderson, K., Bennie, J.J., Milton, E.J., Hughes, P.D.M., Lindsay, R., Meade, R.(2009). Combining LiDAR and IKONOS data for eco-hydrological classification of an ombrotrophic peatland. Journal of Environmental Quality, 39, 1-14.

• Bennie, J.J., Anderson, K., Wetherelt, A.(2011). Measuring biodiversity across spatial scales in a raised bog using a novel paired-sample diversity index. Journal of Ecology, 99(2), 482-490.

• Bilotta, G., Brazier, R.E., Krueger, T., Butler, P., Freer, J., Hawkins, J., Macleod, C.J.A., Haygarth, P.M., Quinton, J.(2010). Assessing Catchment-Scale Erosion and Yields of Suspended Solids from Improved Temperate Grassland. Journal of Environmental Monitoring, 12, 731-739

• Brazier, R.E., Parsons, A.J., Powell, D.M., Wainwright, J.(2006). Scale relationships in hillslope runoff and erosion. Earth Surface Processes and Landforms, 31(11), 1384-1393.

ABOUT THE SUPERVISORS

Dr Karen Anderson is a Senior Lecturer in remote sensing at the University of Exeter, Cornwall Campus. Her research is focused on proximal remote sensing techniques for fine scale assessment of soils and peatlands; calibration validation activities supporting Earth observation science, landscape structure and spatial data analysis, and spatial visualisation. She works closely with Brazier on the ongoing mires on the moor project. Read Karen’s profile.

Dr Iain Hartley is a Lecturer in physical geography at the University of Exeter, Streatham Campus. Iain specialises in carbon cycle feedbacks to global change, soil carbon dynamics, links between carbon and nutrient cycling, methane fluxes, and managing the terrestrial carbon cycle. Read Iain’s profile.

Dr Richard Brazier is a Senior Lecturer in physical geography at the University of Exeter, Streatham Campus. Richard specialises in research on soil erosion, water quality, modelling, issues of data and model uncertainty. He works closely with Anderson on the ongoing mires on the moor project. Read Richard’s profile.

Further particulars

This project should interest applicants with backgrounds in diverse disciplines and subject areas, including, for example, physical geography, environmental science, applied biogeochemistry and ecology. Applicants should hold a First Class or Upper Second Class Honours degree in a relevant discipline, and ideally, a higher qualification (ie, MSc) in a related field. The successful applicant will benefit from working within a lively and expanding research environment within Geography in the College of Life and Environmental Sciences, University of Exeter. The student will benefit from working in a lively and active research group operating across both Streatham and Cornwall campuses.

For eligible candidates the award will cover Home/EU tuition fees for three years and provide a maintenance award of £13,590 per year for three years in addition to travel costs for UK based fieldwork and meetings. For further information, or informal discussion about the position, please contact: Dr Karen Anderson +44 (0)1326 371854, karen.anderson@exeter.ac.uk, Dr Iain Hartley +44 (0)1392 724362, i.hartley@exeter.ac.uk, Dr Richard Brazier +44 (0)1392 724443, r.e.brazier@exeter.ac.uk