Abstract
Urine deposited onto grazed pastures is the main source of anthropogenic nitrous oxide (N
2
O) in New Zealand. Low soil pH (ca 5.0) has been linked to increases in the proportion of N
2
O to N
2
emitted through soil denitrification. However, total denitrification rates and N
2
O emissions can increase with soil pH up to ca 7.0-8.0. We conducted an incubation experiment and a field study to examine the potential to mitigate total N
2
O emissions from urine deposition by increasing the soil pH through liming. The incubation study used three different soils where the pH was adjusted to 6.5, 6.9 and 7.4. Cumulative N
2
O emissions following synthetic urine application at 630 kg N ha
−1
increased with increasing soil pH. The field study, where soil pH was adjusted to 6.6, 7.0 and 7.1, had synthetic urine applied one year later at 600 kg N ha
−1
. Within the pH range studied, increasing pH did not have a significant effect on N
2
O emissions following urine application. Both experiments suggest adjusting soil pH from ca 6 to ca 7 is not an effective tool for reducing N
2
O emissions from urine patches.