VEGETATIVE FILTER STRIP REMOVAL OF METALS IN RUNOFF FROM POULTRY LITTER-AMENDED FESCUEGRASS PLOTS

Runoff from land areas amended with poultry (Gallus gallus domesticus) manure cart contain elevated concentrations of metals such as Cu, Fe, and Zn. Vegetative filter strips (VFS) can reduce runoff concentratio ns of animal manure components, but reported studies have typically fo cused on nutrients and solids rather than metals. This experiment asse ssed the impact of VFS length (0 to 12 m) on concentrations and mass l osses of Cu, Fe, K, Na, Ni, and Zn in runoff from fescuegrass (Festuca arundinacea Schreb.) plots (1.5 m wide x 6 and 12 m long) treated wit h poultry litter: The runoff was produced from simulated rainfall appl ied at 50 mm h(-1) until 1 h of runoff had occurred. Runoff Ni concent rations were below detection levels in all cases. Concentrations of Cu , Fe, K, Na, and Zn did not differ between litter-treated plot lengths but were significantly (p < 0.001) affected by VFS length, decreasing in an approximately first order fashion. Means separation indicated t hat concentrations of Cu, Fe, K, and Zn did not significantly decrease after a VFS length of 3 m, while Na concentrations decreased up to a VFS length of 6 m. Mass transport of only Cu significantly decreased w ith increasing VFS, suggesting that VFS removal mechanisms such as ads orption to clay particles might play a larger role with regard to Cu t han to Fe, K, Na, and Zn.