Fig. 4. Bedding x location effects on mean (±1 SE) mass loads of dissolved reactive phosphorus, DRP (a), total P (b), and NH4–N (c) in runoff from a feedlot in southern Alberta in 1998. Mean values with the same lowercase letter are not significantly (P > 0.05) different. Labels on the x axis are ST (straw), WD (wood chips), BP (bedding pack), and PF (pen floor).