Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 1, 2003
Publication Date: November 2, 2003
Citation: El Balaa, M.F., Adeli, A., Rowe, D.E., Brink, G.E. 2003. Suitability of bacterial indicators in identifying runoff from poultry litter amended soil [abstract]. Agronomy Abstracts. CD-ROM.
In this study, broiler litter (equivalent to 9 Mg/ha) was applied to established bermudagrass on Ruston sandy loam soil in (144x20x10) troughs set at a 7% slope. Control and liter-amended troughs were rained on using a rain simulator to determine the effect of single rain events (0, 3, 6 and 9 d, at 36 mm/h) and 7 repeated rain events (at 3-day intervals) on runoff water quality. Surface runoff was collected for 18 min after its onset, and analyzed for fecal streptococci, coliforms, fecal coliforms, and total aerobic plate counts. Differences between coliform and fecal coliform counts were more noticeable during repeated rain events. Identification of the most predominant types revealed that Enterobacter cloacae and Alcaligenes xylosoxidans predominated in runoff water from both litter-amended and control soil, thus providing little resolution for differentiation between treatments. Fecal streptococci proved to be the more reliable indicator for differentiating between treatments. Identification of the most predominant type revealed that E. faecium constituted (66.7%) of recovered fecal streptococci. Fecal streptococcal counts of the same samples stored at 4 degrees C showed no-significant difference upon recounts over 9 days of refrigerated storage. Fecal streptococci proved to be the more reliable indicator of litter amendment, when compared to coliform and fecal coliforms.