Movement and persistence of fecal bacteria in agricultural soils and subsurface drainage water: A review
Canadian Biosystems Engineering , 44 , 2002
Jamieson, R.C., Gordon, R.J., Sharples, K.E., Stratton, G.W., Madani, A.
The presence of pathogenic bacteria in public and private water systems has emerged in the past year as a priority water quality issue. Livestock agriculture is considered one of the primary causes of bacterial contamination of surface and ground waters. The application of animal manures to tile drained land, and the subsequent transport of pathogens with subsurface drainage water to surface water systems, has been identified as a major pathogen transport pathway. The objective of this review is to summarize the information that has been produced with respect to the survival of fecal bacteria in soil waste systems and their transport to tile drainage water. Factors influencing fecal bacteria survival include moisture, soil type, temperature, pH, manure application rate, nutrient availability, and competition. Cool, moist environments are considered optimal for bacterial survival. Field scale transport studies have shown significant transport of bacteria to tile drains under common manure management practices. Results from column and field studies suggest that the transport of bacteria through undisturbed soils is primarily controlled by macropore flow phenomena. Manure management strategies intended to reduce bacterial transport to tile drains, such as deep tillage, may conflict with other environmental management concerns. Further research is required to: (i) assess the effects of alternate cultivation practices on bacterial transport, (ii) verify that enteric pathogens behave similar to indicator organisms, and (iii) evaluate the effects of manure pre-application treatment methods, such as long-term storage and composting, on bacterial survival.