Assessing Controlled Traffic Farming as a Precision Agriculture Strategy for Minimising N2O Losses

Intensive vegetable farming emits high nitrous oxide (N2O) due to traffic-induced compaction, highlighting the need for preventing nitrogen (N) losses through better traffic management. This study examined the effects of Controlled Traffic Farming (CTF) and Random Traffic Farming (RTF) on N2O emissions using intact soil cores (diameter: 18.7 cm; depth: 25 cm) collected from a vegetable production system in Pukekohe, New Zealand. Soil cores from CTF beds, CTF tramlines, and RTF plots were analysed under fertilised (140 kg N/ha) and unfertilised conditions. N2O fluxes were monitored over 58 days using gas chambers. The fertilised RTF system significantly (p < 0.05) increased N2O emissions (5.4 kg N2O–N/ha) compared to the unfertilised RTF system (1.53 kg N2O–N/ha). The emission from fertilised RTF was 46% higher than the maximum N2O emissions (3.7 kg N2O–N/ha) reported under New Zealand pasture conditions. The fertilised CTF system showed a 31.6% reduction in N2O emissions compared to fertilised RTF and did not differ significantly from unfertilised CTF. In general, CTF has demonstrated some resilience against fertiliser-induced N2O emissions, indicating the need for further investigation into its role as a greenhouse gas mitigation strategy.