The effect of preferential flow of dairy cow urine and simulated rainfall on movement of potassium through undisturbed topsoil cores.

摘要: Cores of undisturbed topsoil (15 cm in depth and diameter) were taken from a range soil types to controlled climate chamber. Urine dairy cows was spiked with tritiated water (3H2O) then applied these cores which had moisture contents near field capacity. Liquid draining cores, as direct consequence urine application, contained up 72% the water, 74% potassium (K), 62% nitrogen (N) 80% chloride (Cl) urine, indicating that could flow preferentially beyond 15 soils. The activity tritium concentrations K, N Cl effluent indicated this preferential movement occurred too quickly for sorption reactions occur between surface majority solutes urine. After ceased, amounts K leached by subsequent simulated rain events much smaller than losses immediately following application. Leaching particularly small (accounting 3-15% K) when moved through thus bypassing micropores or been sorbed soil. Overall, results suggest substantial (and N) grazed pastures may urination event due cow profile, at least soils are capacity time deposition. extent will be more dependent upon structural characteristics rather chemical characteristics.