Background: Diffuse faecal pollution impacts on the microbial quality of freshwaters and subsequent downstream Transport impacts on coastal bathing, recreational and shellfish production waters. Faecal indicator bacteria (FIOs) and bacterial pathogens such as E. coli O157; Campylobacter and Salmonella from agricultural run off, sewage and septic tank effluent and wildlife inputs are transported either bound to sediment particles or as free or clumped cells during peak flows.
There is evidence that particle-associated bacteria tend to sediment out during transport downstream and can remain as a “sediment pool” within the water body until they either die-off or further high flows or disturbance initiate resuspension. This has been shown in preliminary stream channel experiments here at JHI.
Understanding the dynamics of FIOs and pathogens through the transition from freshwater to coastal sediments helps us to assess where risk hotspots will occur and implement more effective (and cost effective) mitigation measures protecting human health and coastal industries.
This Ph.D. project draws together recognised expertise in characterisation of coastal sediments (St. Andrews University) with expertise in pathogen transport, survival and interactions with sediment and biofilm (JHI) and opportunity to utilise well characterised experimental and field sites and complementary skills and equipment from each group.
Aims:The overarching aim of the project is to understand the sediment and environmental characteristics that promote greater or lesser retention and resuspension of FIOs and bacterial pathogens through the transition from fresh water to marine (tributary, river and estuarine environments). A secondary aim is to link the findings to existing sediment transport models and catchment characteristics.
Funding Notes:
The studentship is funded under the JHI/University Joint PhD programme and will be undertaken in conjunction with the University of St Andrews. Prof D Paterson will be the principal university supervisor on this project.
Candidates are urged strongly to apply as soon as possible so as to stand the best chance of success. A more detailed plan of the studentship is available to suitable candidates upon application. Funding is available for European applications, but Worldwide applicants who possess suitable self-funding are also invited to apply.
References:
•Quilliam, R.; Williams, A.P.; Avery, L.; Malham, S.; Jones, D., (In press) Unearthing human pathogens at the agricultural-environment interface: a review of current methods for the detection of e-coli O157 in freshwater ecosysems., Agriculture, Ecosystems and Environment.
•Vinten, A.J.I.; Artz, R.R.E.; Thomas, N.; Potts, J.M.; Avery, L.M.; Langan, S.J.; Watson, H.; Cook, Y.; Taylor, C.; Abel, C.; Reid, E.; Singh, B.K., (2011) Comparison of microbial community assays for the assessment of stream biofilm ecology., Journal of Environmental Methods, 85, 190-198.
•Colloid-pathogen interactions and bacterial transport. - Avery, L.M.; Vinten, A.J.A.; Crooks, B. - Proceedings of the 2010 International Symposium on Waterborne Pathogens, Manhattan Beach, California, 2-4 May 2010.
•Avery, L.M.; Williams, A.P.; Killham, K.; Jones, D.L., (2009) Heat and lime treatment as an effective control method of e-coli O157:H7 in organic wastes., Bioresource Technology, 100, 2692-2698.
•Avery, L.M.; Williams, A.P.; Killham, K.; Jones, D.L., (2008) Survival of Eschericgia coli O157:H7 in waters from lakes, troughs, rivers, puddles and animal drinking troughs., The Science of the Total Environment, 389, 378-385.