Stickstoffaufnahme und Biomasseertrag von Zwischenfrüchten und deren Auswirkungen auf Bodennitratgehalte und die Folgekultur unter den Bedingungen des Ökologischen Landbaus im pannonischen Klimagebiet

Summary

Data on the potential of catch crops to reduce soil nitrate contents, on their N accumulation and biological nitrogen fixation (BNF) are lacking for organic farming in the dry, pannonic region of Eastern Austria. The effect of legume, non-legume, and legume + non-legume crops used as catch crops on inorganic soil nitrogen, crop biomass and crop N, and BNF were tested in comparison to bare fallow. Non-legumes and legumes + non-legumes were more efficient than legumes in reducing inorganic soil N contents in autumn and nitrate contents in soil solution from the subsoil in winter. This reduction in inorganic soil N did not last until March of the following year due to N mineralisation from the mulch. The legume + non-legume mixture contained a larger amount of crop N than both legumes and non-legumes. This was due to the combined effect of soil-N uptake by the non-legumes and BNF by the legumes in the mixture.