Fate and transport of microplastics in partially saturated soils

Recent research indicates that microplastics are now ubiquitous in the environment: they have been found in lakes, rivers, and even groundwater. Not only may they themselves pose a health risk if consumed, microplastics may act as a vector and promote the spread of other harmful substances in the environment that may otherwise be immobile. While microplastics in surface waters have received a lot of attention, relatively little is known about the processes that control their fate and transport in the subsurface. The aim of this project is to improve our understanding of the fate and transport of microplastics in both groundwater (in fully water-saturated regions of the subsurface) and in soils only partially saturated with water.

 The successful candidate will determine the spatial distribution of microplastics within artificial soil columns using X-ray micro-computed tomography under a range of grain roughness, residual air saturation, ambient flow velocities, and influent microplastic concentration. A protocol recently developed in the research group (Ibekwe et al 2019) will be adapted to create artificial soils with systematically varied textures. Using the data as a guide, the candidate will develop predictive models for microplastic retention as a function of grain roughness and residual saturation. Depending on interest, the observations may be complemented by experiments using real soil samples or microplastics of different sizes, shapes, and materials.

The successful candidate will interact with members of two groups within the University: (a) the Fluid Mechanics Research Group in the School of Engineering and (b) the Soil Biophysics Research Group in the School of Biological Sciences. Members of the Fluid Mechanics Research Group use different combinations of laboratory experiments, field measurements, numerical simulations, and theoretical analysis to study physical processes associated with a wide range of applications, including groundwater remediation, geological CO₂ storage, and coastal erosion. The Soil Biophysics Research Group explores the interaction between physical and biological processes in soil, including how changes to the surface properties of soil particles by exudates affects hydrological and mechanical behaviour.

Previous laboratory experience and familiarity with MATLAB are essential. Experience in programming and image processing will be an advantage.

Selection will be made on the basis of academic merit. The successful candidate should have, or expect to obtain, a UK Honours degree at 2.1 or above (or equivalent) in engineering or physical science discipline.

APPLICATION PROCEDURE:

Formal applications can be completed online: https://www.abdn.ac.uk/pgap/login.php

• Apply for Degree of Doctor of Philosophy in Engineering

• State name of the lead supervisor as the Name of Proposed Supervisor

• State ‘Self-funded’ as Intended Source of Funding

• State the exact project title on the application form

When applying please ensure all required documents are attached:

• All degree certificates and transcripts (Undergraduate AND Postgraduate MSc-officially translated into English where necessary)

• Detailed CV, Personal Statement/Motivation Letter and Intended source of funding

Informal inquiries can be made to Dr Y Tanino (ytanino@abdn.ac.uk) with a copy of your curriculum vitae and cover letter. All general enquiries should be directed to the Postgraduate Research School (pgrs-admissions@abdn.ac.uk)