Small farm plots and application of simulated rain to determine the potential for bacterial runoff after poultry litter surface application to bermudagrass

Authors: Brooks, John; Adeli, Ardeshir

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/18/2008
Publication Date: 6/2/2008
Citation: Brooks, J.P., Adeli, A. 2008. Small farm plots and application of simulated rain to determine the potential for bacterial runoff after poultry litter surface application to bermudagrass [abstract]. Mississippi 38th Water Resources Conference Proceedings. p. 17.

Interpretive Summary:

Technical Abstract: Land application of poultry litter is an economical and environmentally viable use of this manure byproduct. Runoff following a rain event is one possible source of environmental contamination resulting from manure application. In this second part of a two-part study, a series of treatments involving litter (two rates), inorganic fertilizer, and no fertilizer controls were added to bermudagrass plots held on the Mississippi State south farm to simulate “real-world” conditions and extend the baseline data gathered during the greenhouse trials previously conducted. A rainfall simulator was used to simulate precipitation events and following each rain event, runoff samples were collected for microbial analyses. Total Heterotrophic Plate Count (HPC) bacteria, antibiotic resistant bacteria (ARB), thermal-tolerant coliforms, enterococci, staphylococci, and Clostridium perfringens were investigated. Over a period of 60 days, 5 rain events were simulated using a portable rain applicator and results indicated that staphylococci, enterococci, and clostridia correlated well with manure application, corroborating the previous greenhouse study. Analysis of runoff concentration means demonstrated that in most cases litter application increased the presence of indicator microorganisms in runoff water. Traditional indicators such as thermal-tolerant and total coliforms performed poorly as fecal indicators relative to the other bacteria assayed in this study. No “frank” pathogens such as Salmonella or Campylobacter were detected in the applied litter or runoff. This study corroborated previous evidence suggesting that poultry litter land application and subsequent runoff can be simulated in a greenhouse using controlled conditions and that the presence of poultry litter in runoff can be detected using staphylococci, enterococci, and C. perfringens.