Nitrogen cycle factors contributing to N 2 O production from fertilizers

Nitrogen cycle factors contributing to N 2 O production and associated ozone perturbations are examined. It is pointed out that fertilizer nitrogen losses are non‐linear and increase with application rate. Losses are apportioned between rapid denitrification (∼ 1 year) and slower transfer processes of 10² to 10³ years between nitrogen reservoirs. It is concluded that different estimates of N 2 O production result from selecting nitrogen models with different denitrification and transfer efficiencies. A significant ozone perturbation cannot be ruled out because of uncertainties in the relative efficiency of agricultural denitrification.