Polyacrylamide (PAM) is used in agriculture to reduce soil erosion and has been reported to reduce turbidity, nutrients, and pollutants in surface runoffwater. The objective of this work was to determine the effect of PAM on the concentration of enteric bacteria in surface runoffby comparing four enteric bacteria representing phenotypically different motility and hydrophobicity from three soils. Results demonstrated that bacterial surface runoffwas differentially influenced by the PAM treatment. Polyacrylamide treatment increased surface runofffor adhered and planktonic cells from a clay soil; significantly decreased surface runoffof adhered bacteria, while no difference was observed for planktonic bacteria from the sandy loam; and significantly decreased the surface runoffof planktonic cells, while no difference was observed for adhered bacteria from the clay loam. Comparing strains from a final water sample collected after 48 h showed a greater loss of Escherichia coli while Salmonella enterica serovar Poona was almost not detected. Thus, (i) the PAM efficiency in reducing the concentration of enteric bacteria in surface runoffwas influenced by soil type and (ii) variation in the loss of enteric bacteria highlights the importance of strainspecific properties that may not be captured with general fecal indicator bacteria.
- Programområde 2: Vandressourcer