N-Bilanzen ökologischer und konventioneller Praxisbetriebe in Norddeutsch-land – Ergebnisse aus dem Projekt COMPASS

Summary

Nutrient balances are important agri-environmental indicators, which describe the magnitude of potential nutrient losses from farming systems to the environment. In order to analyze production systems at the entire farm scale, nitrogen balances and other agri-environmental indicators were assessed on 32 organic and conventional farms in Northern Germany. On organic farms, nitrogen fixation of legumes was determined on representative fields. Irrespective of the specialization (all-arable farms, dairy farms), nitrogen surpluses were always pronouncedly lower on organic farms compared to conventional farms. Organic farms generally conducted a sustainable nutrient management. However, the total nitrogen supply at the farm scale was not sufficient on many organic arable farms.