ARS | Publication request: Investigations into the transport behavior of E. coli and the sorption of phosphorus to soil

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 4, 2010
Publication Date: November 5, 2010
Citation: Bolster, C.H. 2010. Investigations into the transport behavior of E. coli and the sorption of phosphorus to soil. Meeting Abstract. Abstract only.

Technical Abstract: Land application of animal wastes can lead to water quality degradation if manure-derived pathogens and/or nutrients reach water supplies. To minimize agriculture’s impact on the environment, factors controlling pathogen and nutrient movement through the landscape must be better understood. Investigating these factors is the focus of on-going research at USDA-ARS’s Animal Waste Management Research Unit. In particular, research has focused on the role isolate diversity plays on the subsurface transport of E. coli, a commonly used indicator of possible fecal contamination of water. Results from this research have shown that a significant amount of diversity exists in cell properties and transport behavior among different E. coli isolates. This diversity has important implications in modeling E. coli movement in the environment and should caution against making generalizations about the transport behavior of E. coli based on experimental results from a single strain. Research has also focused on developing and testing improved regression methods for fitting sorption models to phosphorus (P) data so that the sorption behavior of P can be better understood. Results from this research show that the use of linearized sorption equations needlessly limits the ability to model sorption data with good accuracy. Furthermore, this research shows that traditional weighted regression methods are inadequate for fitting P sorption data. A new weighting method was developed and was shown to improve assessments of model fits. Applying this method to several data sets shows that the Langmuir model, the most commonly used sorption model, is rarely the most appropriate model for describing P sorption to soils.