| Autor: |
Wyness AJ; Sediment Ecology Research Group, Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, St. Andrews KY16 8LB, UK. a.wyness@ru.ac.za.; Environmental and Biological Sciences Group; The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK. a.wyness@ru.ac.za.; Coastal Research Group, Department of Zoology and Entomology, Rhodes University, Grahamstown 6139, South Africa. a.wyness@ru.ac.za., Paterson DM; Sediment Ecology Research Group, Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, St. Andrews KY16 8LB, UK. dp1@st-andrews.ac.uk., Rimmer JEV; Sediment Ecology Research Group, Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, St. Andrews KY16 8LB, UK. jr49@st-andrews.ac.uk., Defew EC; Sediment Ecology Research Group, Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, St. Andrews KY16 8LB, UK. ecd2@st-andrews.ac.uk., Stutter MI; Environmental and Biological Sciences Group; The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK. Marc.Stutter@hutton.ac.uk.; Lancaster Environment Centre; Lancaster University, Bailrigg, Lancashire LA14YQ, UK. Marc.Stutter@hutton.ac.uk., Avery LM; Environmental and Biological Sciences Group; The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK. Lisa.Avery@hutton.ac.uk. |
| Abstrakt: |
Estuarine sediments are a reservoir for faecal bacteria, such as E. coli , where they reside at greater concentrations and for longer periods than in the overlying water. Faecal bacteria in sediments do not usually pose significant risk to human health until resuspended into the water column, where transmission routes to humans are facilitated. The erosion resistance and corresponding E. coli loading of intertidal estuarine sediments was monitored in two Scottish estuaries to identify sediments that posed a risk of resuspending large amounts of E. coli . In addition, models were constructed in an attempt to identify sediment characteristics leading to higher erosion resistance. Sediments that exhibited low erosion resistance and a high E. coli loading occurred in the upper- and mid-reaches of the estuaries where sediments had higher organic content and smaller particle sizes, and arose predominantly during winter and autumn, with some incidences during summer. Models using sediment characteristics explained 57.2% and 35.7% of sediment shear strength and surface stability variance respectively, with organic matter content and season being important factors for both. However large proportions of the variance remained unexplained. Sediments that posed a risk of resuspending high amounts of faecal bacteria could be characterised by season and sediment type, and this should be considered in the future modelling of bathing water quality. |
