Nitrous oxide (N(2)O) emissions from grazing animal excreta are estimated to be responsible for 1.5 Tg of the total 6.7 Tg of anthropogenic N(2)O emissions. This study was conducted to determine the in situ effect of incorporating biochar, into soil, on N(2)O emissions from bovine urine patches and associated pasture uptake of N. The effects of biochar rate (0-30 t ha(-1)), following soil incorporation, were investigated on ruminant urine-derived N(2)O fluxes, N uptake by pasture, and pasture yield. During an 86-d spring-summer period, where irrigation and rainfall occurred, the N(2)O fluxes from (15)N labeled ruminant urine patches were reduced by >50%, after incorporating 30 t ha(-1) of biochar. Taking into account the N(2)O emissions from the control plots, 30 t ha(-1) of biochar reduced the N(2)O emission factor from urine by 70%. The atom% (15)N enrichment of the N(2)O emitted was lower in the 30 t ha(-1) biochar treatment, indicating less urine-N contributed to the N(2)O flux. Soil NO(3)(-)-N concentrations were lower with increasing biochar rate during the first 30 d following urine deposition. No differences occurred, due to biochar addition, with respect to dry matter yields, herbage N content, or recovery of (15)N applied in herbage. Incorporating biochar into the soil can significantly diminish ruminant urine-derived N(2)O emissions. Further work is required to determine the persistence of the observed effect and to fully understand the mechanism(s) of the observed reduction in N(2)O fluxes.