Altering Soil Nutrient Concentrations in Animal Congregation Areas of an Abandoned Beef Cattle Backgrounding Feedlot through Soil Amendments.

Animal congregation around feeders and water sources is common in intensive beef cattle production systems. The resulting intense manure and urine deposition by congregating animals enriches soils around feeders and water troughs with manure born soil nutrients. Unless properly managed, soil nutrients accumulated in animal congregating areas can deteriorate quality of soil and surface/underground water. We tested three soil amendments; alum (KAl(SO₄)₂.12H₂O), biochar, and lime (CaCO₃) with a control on pre identified feeder area of an abandoned beef cattle backgrounding site to manage high soil nutrientlevels. We compared soil pH, Mehlich 3 P (M3 P), Fe, Cu, and Zn level change two years after the amendments. Alum amendment reduced soil pH from7.2 to 6.7; Zn from 29.4 to 21.7 mgkg^-1; Mehlich 3 P from 771.2 to 585.9 mgkg^-1. Biochar application marginally reduced soil M3 P, Fe, and Cu levels. Lime addition did not alter soil pH, however slightly reduced soil Fe and Cu content. Although effect of alum application on reducing soil nutrient levels in feeder areas was evident in the short run, data for much longer period are required to evaluate long term effects of soil amendments.