Postgraduate research opportunities Linking phytoremediation to energy crops for sustainable bioenergy and land restoration

This PhD project will investigate the potential of using energy crop species grown on contaminated land to combine sustainable bioenergy production with land restoration and pollution mitigation.  It is part of the H2020 CERESiS project, which will provide access to field trials and an opportunity to travel to project meetings and engage in an exciting international project which is helping to deliver sustainable aviation fuels towards meeting Net Zero targets. 

You’ll also work closely with a local social enterprise, Eadha Enterprises who specialise in using native aspen for woodland creation and land restoration. Thus the research will also have direct environmental, social and economic impacts on Scottish communities affected by the legacy of mining and industrial dereliction.

The project is full-funded for both tuition fees and tax-free studentship at £16,062 pa (rising to £17,552 over three and a half years) and part of a cohort of PhD students starting their trans and multi-disciplinary studies in the recently established Centre for Sustainable Development.

In common with the ethos of the Centre, Department and project we welcome applications from a range of backgrounds, from geosciences to environmental science, environmental chemistry, environmental engineering, biological or agricultural sciences.

Aim & objectives

The aim of this PhD is to address two truly global issues:

1. contaminated land, specifically inorganic and metal contamination from coal mining
2. organic contaminants from hydrocarbon exploitation or use

The focus will be on using novel energy species for phytoremediation, as these have been shown in our previous research to have greater productivity than conventional energy crops, such as short-rotation coppice willow or Miscanthus¹, especially on the variety of non-agricultural landbanks that might be used without impacts on food production².

When combined with organic waste amendments this approach has the co-benefit of significant additional greenhouse gas emission reduction through soil carbon addition and prolonged storage³, while providing a sustainable and nature-based approach to contaminated land management or former mineral workings⁴.

Although contaminant concentrations in energy crop biomass are lower, the far greater biomass produced can still remove greater quantities of contaminants than specialist metal-accumulating hyper-accumulator plants, with lower contamination levels also meaning easier use for biofuels (CERESiS, unpublished).

Our recent literature review^{3, 5} suggests that reed canarygrass (Phalaris arundinacea) has the potential to phyto-degrade organic contaminants, published studies exist for a few complex organic contaminants (e.g. certain PCBs, the PAH pyrene and the explosives TNT and RDX), but that current laboratory studies and especially field trial verifications are extremely limited, especially for more common hydrocarbon soil contaminants such as petroleum residues.

Specific objectives for this PhD studentship are as follows:

• To determine the tolerance of Phalaris arundinacea to common hydrocarbon residues in soil
• To test the performance of Phalaris arundinacea to the specific challenges of establishment on coal mining wastes and disturbed lands ⁽²⁾, including shaley or stony soils, heavy clays, high salinity or sulphate, low pH and fertility)
• To devise suitable amendment strategies utilizing available low-cost organic or inorganic waste products to address the issues identified above

Methodologies

Methodologies will combine laboratory pot trials with measurements at existing field plots, allowing replicated laboratory results to be verified in actual environmental conditions. The subject matter and supervisory team are both inter and trans-disciplinary, combining geochemistry, geo-environmental engineering, plant sciences, environmental science, energy provision, circular economy, nature-based solutions with the practical and social aspects of sustainable development projects.

Training

The candidate will receive training in a variety of transferable skills, laboratory work, field trials and environmental issues, with any specific training needs identified and addressed. The student will benefit from a range of interdisciplinary and multi-disciplinary experiential learning, which is likely to include:

• fieldwork skills assessing sites, sampling soils, observing plant growth
• generic laboratory skills planning, implementing and monitoring plant growth trials
• training in specialist analytical chemistry aspects as required
• exposure to regulatory, health & safety and business aspects of remediation
• data analytical skills, using quantitative and qualitative data
• communication skills, reporting results to supervisory team, non-specialist, technical and academic audiences at local conferences or workshops (e.g. Scottish Contaminated Land Forum, Society for Environmental Geochemistry & Health, EPSRC Supergen Bioenergy Hub researcher days and their ECR SHARE Network) and Eadha activities and training events

References

⁽¹⁾ Lord R. (2015). Reed Canarygrass (Phalaris arundinacea) outperforms Miscanthus or willow on marginal soils, brownfield and non-agricultural sites for local, sustainable energy crop production. Biomass and Bioenergy 78, 110-125

⁽²⁾ Mellor, P., Lord, R. A., João, E., Thomas, R. & Hursthouse, (2021), Identifying non-agricultural marginal lands as a route to sustainable bioenergy provision - a review and holistic definition. Renewable and Sustainable Energy Reviews 135, 110220

⁽³⁾ Lord, R & Sakrabani, R 2019, Ten-year legacy of organic carbon in non-agricultural (brownfield) soils restored using green waste compost exceeds 4 per mille per annum: benefits and trade-offs of a circular economy approach. Science of the Total Environment, vol. 686, pp. 1057-1068.

⁽⁴⁾ Lord, R., Moffat, A., Sinnett, D., Phillips, P., Brignall, D., Manning, D. Blue Green Infrastructure on Mineral Sites. In ICE Manual of Blue-Green Infrastructure (C Washbourne & C Wansbury, eds.). Institute of Civil Engineers, London (in press).

⁽⁵⁾ Jensen, E.F., Casler, M.D., Farrar, K., Finnan, J.M., Lord, R., Palmborg, C., Donnison, I. (2018). Reed canarygrass from production to end use In E Alexopoulou (ed.), Perennial grasses for bioenergy and bioproducts, Production, Uses, Suitability and Markets for Giant Reed, Miscanthus, Switchgrass, Reed Canary Grass and Bamboo, Elsevier, Cambridge Massachusetts, pp153-174.