Efficiency of controlled drainage and subirrigation in reducing nitrogen losses from agricultural fields

▶ Controlled drainage and subirrigation reduced nitrate-nitrogen losses in N-E Italy. ▶ Controlled drainage and subirrigation reduced nitrate-nitrogen losses by 71%. ▶ Few drainage events in the fall and spring caused most nitrate-nitrogen losses. ▶ Reduction of drainage flow was a key mechanism to reduce nitrate-nitrogen losses.