Recently Planted Vegetation Strips Reduce Giardia Runoff Reaching Waterways
Journal of Environmental Quality , 37 , 2008

Winkworth, C.L., Matthaei, C.D., Townsend, C.R.

Current methods for tracking pathogens across farmland and into surrounding waterways via runoff are limited and typically have been developed using artifi cially created landscapes. No studies have investigated how Giardia in farm runoff moves across the landscape, despite high prevalence rates in dairy cattle (Bos taurus) worldwide. Here, we report the development of a fi eld-based tracking method specifi c for Giardia movement in runoff and use this technique to compare the pathogen reduction capability of recently planted vegetation strips with bare soil strips cleared of vegetation. Such scenarios represent typical events in schemes to plant vegetation barriers aimed at reducing waterway contamination. A signifi cant treatment eff ect was identifi ed, with 26% fewer Giardia detected in runoff collected from the planted strip (P = 0.006). Th ese results highlight the immediate benefi t of pathogen removal to be gained from vegetation planting. Th e successful discrimination of treatment eff ects by this new technique will enable the assessment of diff erent vegetation types on runoff reduction and the eff ects of plant development over time.