Submitted to: Transactions of the Institute of Ecological Soil Science
Publication Type: Book / Chapter
Publication Acceptance Date: 9/15/2006
Publication Date: 11/18/2006
Citation: Devin, B.A., Pachepsky, Y.A., Shein, E.V., Polyanskaia, L.M., Shelton, D.R., Guber, A.K. 2006. Model of Aquaspirillum and Arthrobacter transport in soils. Transactions of the Institute of Ecological Soil Science. 20(3):207-218. Interpretive Summary: Bacterial transport through soils is attracting more attention because soil serves as an environmental bacterial filter, thereby reducing microbial contamination of ground water. Bacteria breakthrough in soils has demonstrated several features that set such transport apart from the transport of chemical pollutants. Two of such features are the appearance of concentrations in soil effluent that are larger than influent concentrations, and the presence of several maxima in effluent concentrations. These features have been observed in our earlier experiments with Aquaspirillum and Arthrobacter suspensions applied to soil columns. We developed the "limited entrapment model" to simulate the observed bacterial transport. The model assumed that (a) the capacity of soil pore space to trap bacteria is limited, (b) the bacteria entrapment accelerates as the amount of trapped bacteria approaches the soil trapping capacity, and (c) the trapped bacteria form cell clusters that may be released back to the soil solution but travel slowly and may become re-trapped because of their size. The new model provided a satisfactory fit to data and indicated that both cell cluster formation and the limited entrapment may be significant factors of bacterial transport through soil.
Technical Abstract: It is proposed to simulate transport of Aquaspirillum and Arthrobacter transport in soils using the hypothesis of limited entrapment of bacteria in soil.