Nitrogen balances in organic and conventional arable crop rotations and their relations to nitrogen yield and nitrate leaching losses

Abstract

Nitrogen (N) flows in organic cropping systems differ considerably from those in conventional systems. The difference is particularly due to the N in organic materials in organic systems as opposed to the mineral N in fertilizer in conventional systems, which differently affect crop N supply and N losses. This implies different responses of conventional and organic cropping systems to N inputs and N management. Therefore, N flow dynamics were studied in a range of arable cropping systems with 4-year crop rotations at three different sites in Denmark varying in soil (coarse sand, loamy sand and sandy loam) and climatic conditions. The long-term field experiments included an incomplete factori..