|Why is this project important?
Conveyance of fine sediment through river systems is of major interest to many stakeholders owing to its significance with respect to contaminant and nutrient transfer, instream habitat, sustainability of infrastructure (hydropower, flood defences), flood risk and soil loss from agriculture. Traditionally the most robust suspended sediment concentration dynamics estimates have been based on bank side turbidity monitoring. However, in rivers with large cross sectional areas and, in particular, those with complex and dynamic hydromorphology, sediment and water fluxes will not be uniformly distributed throughout the cross section. Given that these variations are poorly understood and are likely to be important in the estimation of sediment fluxes this represents a priority research area.
The aim of this project is to understand cross sectional variations in suspended sediment to enable its account in flux and budget estimation, and habitat suitability assessment. It is a collaborative project between the Centre for Ecology and Hydrology, Lancaster Environment Centre and Environment Agency. More specifically, the objectives of the proposed project are threefold. Firstly, simultaneous, co-located measurements of river hydraulics and suspended sediment will be obtained from both in channel and floodplain environments. Secondly, observed variations will be investigated to elucidate cross sectional changes in sediment transport and their controls. Knowledge will be gained by making observations in carefully selected varied catchment settings (e.g. contrasting land-uses, soils, hydrology, in-stream biota). Finally, the potential of calibrating Acoustic Doppler Current Profiler (ADCP) backscatter data to suspended sediment concentration will be assessed.
A new generation state of the art ADCP instrument (SonTek’s River Surveyor M9) will be used to make hydraulic measurements. The instrument will be deployed remotely using a Differential Global Positioning System-enabled, radio-controlled boat to allow the safe survey of large and often inaccessible river and floodplain flows. The ADCP backscatter data will be evaluated against in situ physical water samples (particle size and mass) and independent direct measurements (turbidity and particle size; using a LISST100X instrument) to provide robust calibration. Particle size of samples will also be determined in the laboratory using a Malvern Mastersizer 1000 instrument. This important but detailed calibration procedure is particularly well suited to a research project and will contribute to the delivery an optimised protocol for the calibration of ADCP backscatter.
Results of the research would be of direct relevance to those involved in river management and model development and, in particular, those with an interest in Working With Natural Processes (WWNP) who are focused on mitigating the effects of changes in land use/management, climate and water resources. The proposal builds on the current research and experience of its application from all three partners (CEH, LEC and EA) and will form the basis for partnership working in areas such as sedimentology (including modelling of floodplain sediment losses), ecohydraulics, hydromorphology and water quality monitoring (e.g. at the CEH River Lambourn Observatory). Through this partnership important links with estuarine and terrestrial science will also be developed. It is likely the research would focus on key sites throughout the River Thames basin to benefit from and complement existing NERC research centre national capability effort.
What's in it for you?
The PhD project provides comprehensive personal and professional development training alongside extensive opportunities for the student to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and policy partners.
Training will be also given in research methods, experimental design, field and laboratory measurement methods, in-stream biota recognition, flow measurement techniques (e.g. use of Acoustic Doppler Current Profiler (ADCP) including driving a radio-controlled boat), GPS surveying, in situ sediment measurement techniques (e.g. use of state of the art turbidity and particle size instruments), laboratory techniques for analysing sediment samples (e.g. Malvern Mastersizer 1000 instrument) and computing techniques for data presentation and analysis (e.g. Tecplot, programming in R, ArcGIS). The student will also benefit from working alongside CEH and LEC scientists, field ecologists, and other PhD students. The student will also be encouraged and supported in engaging with stakeholders (environmental regulators and advisory bodies) to promote the potential of closer consideration of natural processes in catchment management.
Who should apply?
Candidates for this project should have a minimum of an Upper Second Class Honours degree or equivalent in engineering, environmental science, physics, geography, mathematics, ecology or a similar discipline, and an interest in river flow hydraulics. The candidate will be required to have some knowledge of fluid mechanics and reasonable numerical and computer skills. An interest in fluvial processes in addition to an enthusiasm to undertake field, laboratory and desk based science is essential.
The small print
Studentship funding: Full studentships (UK/EU tuition fees and stipend (£14,057 2015/16 [tax free])) for UK/EU students for 3.5 years. Unfortunately studentships are not available to non-UK/EU applicants.
Academic Requirements: First-class or 2.1 (Hons) degree, or Masters degree (or equivalent) in an appropriate subject.
Deadline for applications: Midnight 31 March 2016
Provisional Interview Date: To Be Confirmed
Start Date: October 2016
For further information or informal discussion about the position, please contact Dr P Rameshwaran (firstname.lastname@example.org) or Dr Andrew Folkard (email@example.com).
suitability for this project and a CV at LEC Postgraduate Research Applications,
Due to the limited time between the closing date and the interview date, it is essential that you ensure references are submitted by the closing date or as soon as possible.
1. Rameshwaran, P; Sutcliffe, A; Naden, P; Wharton, G. 2014 Modelling river flow responses to weed management. In: Schleiss, Anton J.; de Cesare, Giovanni; Franca, Mario J.; Pfister, Michael, (eds.) River Flow 2014. London, Taylor & Francis Group, 467-474.
2. Old, G.H.; Naden, P.S.; Rameshwaran, P.; Acreman, M.C.; Baker, S.; Edwards, F.K.; Sorensen, J.P.R.; Mountford, O.; Gooddy, D.C.; Stratford, C.J.; Scarlett, P.M.; Newman, J.R.; Neal, M.. 2014 Instream and riparian implications of weed cutting in a chalk river. Ecological Engineering, 71. 290-300. 10.1016/j.ecoleng.2014.07.006.
3. Folkard, A.M. 2011 Vegetated flows in their environmental context: a review. Proceedings of the Institution of Civil Engineers - Engineering and Computational Mechanics 164 (1): 3-24. DOI: 10.1680/eacm.8.00006