Evaluating Prairie Buffer Strips to Mitigate the Spread of Antibiotics and Antibiotic Resistance Genes from Manure-Amended Fields

Alyssa Iverson

Iowa State University

Co-Authors:

The use of veterinary antibiotics (VAs) in animal agriculture and subsequent application of manure to farmland has led to elevated levels of antimicrobials and antimicrobial resistance (AMR) in the environment. Prairie strips are an edge-of-field conservation practice with a demonstrated ability to improve water quality in agricultural runoff while having minimal impact on crop production. The STRIPs (Science-Based Trials of Rowcrops Integrated with Prairie Strips) organization at Iowa State aims to demonstrate the impact of prairie strips on reducing the spread of VAs and AMR into the environment.

This presentation will outline the ongoing STRIPs experiments evaluating the possibility of prairie strips as a strategy to mitigate the spread of AMR from manure-amended row crop fields. Research includes field-based rainfall simulations and lab-based flume experiments to assess the ability of a prairie strip to retain VAs and ARGs, in addition to a lab-based soil incubation experiment to characterize VA and ARG occurrence and degradation in prairie strip soil in comparison to row crop soil. Early results of rainfall simulation and flume runoff studies both demonstrate the potential for prairie strips to reduce enterococci and resistant enterococci concentrations in runoff, while early results of soil incubation show that veterinary antibiotics degrade at similar rates between prairie strip soil and row crop soil. Ongoing analysis will assess a strip’s ability to reduce VA and ARG concentrations in overland runoff, as well as compare the occurrence and persistence of antibiotics and ARGs introduced to prairie strip soil and row crop soil through the application of manure.