PhD  research student


Project: Optimising multi-pollutant phytoremediation strategies to sustainably improve raw water quality

The ability of aquatic plants (macrophytes) to assimilate organic and inorganic waterborne pollutants has been demonstrated in controlled laboratory experiments, whilst several small scale field studies (particularly in China) have indicated the potential for efficient pollutant uptake and removal. However, these studies are limited by concentrating on a single plant species and targeting a single pollutant.

Using macrophytes for phytoremediation is a non-invasive strategy for sustainably treating polluted waterbodies, and after sequestering pollutants, macrophytes can be harvested and removed from the water and their biomass used as a soil conditioner, animal feed or as feedstock for bioenergy production; alternatively, the pollutant can be recovered and purified from the plant tissue. The overarching aim of this project is to optimise a series of strategies that can improve water quality by exploiting the ability of aquatic plants to assimilate waterborne pollutants.

This project will investigate, and optimise, environmental phytoremediation strategies, and develop novel approaches for sustainably increasing water quality. Specifically, this project will explore the opportunities for phytoremediation in nutrient enriched and multi-pollutant impacted waters and, crucially, will integrate economic, environmental and engineering dimensions that cut across traditional academic disciplines. Therefore, this project will provide transformative and sustainable solutions to address the increasing demand for raw water security, particularly in a Scottish context, and provide the necessary data for introducing similar management options throughout the UK. The aim is also to contribute towards a strategic blueprint that can be translated to other areas of the world where there is growing pressure on water resources because of increasing population demands, and provide the scientific basis for national scaling-up in countries with significant water security challenges.

The key research objectives of this project is to:

  • Identify aquatic plant combinations that provide maximum sequestration potential for a range of diffuse pollutants;
  • Develop novel ecological engineering solutions, i.e., ‘aquatic rural SuDS’ and ‘floating treatment wetlands’;
  • Carry out field-scale experiments to determine realistic extraction efficiency rates, and model potential for scaling up;
  • Calculate the economic practicality of scaling up phytoremediation strategies in Scotland in both monetary and non-monetary terms.

Using a combined field and laboratory-based experimental approach, this interdisciplinary project will provide the fundamental understanding necessary to deliver a step-change in our understanding of field-scale phytoremediation strategies. In all cases, locally adapted native species of macrophytes will be used in the experimental and treatment systems. The project will be carried out in 4 overlapping phases: (i) Optimising macrophyte community composition for sequestering specific diffuse pollutants; (ii) Maximising removal efficiency of targeted aquatic pollutants through the development of novel engineered ‘Floating Treatment Wetlands’; (iii) Developing ‘aquatic rural SuDS’ – a novel ecological engineering strategy to reduce the aquatic-aquatic pathway for diffuse pollutant transfer (e.g. from areas of aquaculture production) into natural waterbodies; (iv) Scaling-up a socio-economic framework.

This PhD project is funded by the Scottish Government’s Hydro Nation Scholars Programme.

More about me

I graduated from the University of Stirling in 2014 with a BSc in Environmental Geography before undertaking a postgraduate internship investigating methods to remotely sense freshwater environments at the same institute. I then spent time working for an environmental consultancy in the area of waste engineering and pollution control. In 2016 the opportunity to combine his experience in the applied environmental sciences with my academic interests in environmental geography led to the undertaking of a PhD project in ecological engineering, environmental pollution and bioremediation (see below for further information).

Blog posts

Floating treatment wetlands as multi-functional ecosystems – from anecdote to evidence

Scotland the Hydro Nation – lessons for the future of water management

Twitter @jfletcher060816

Talks and Posters

Water Scotland Conference Talk (PowerPoint: Fletcher 2017)

Hydro Nation Poster (Powerpoint: Fletcher 2017)