Entwicklung der Humusgehalte und der Humusqualität in verschiedenen Fruchtfolgen des ökologischen Landbaus

Summary

A high turnover of Humus is one of the goals in organic farming. The effect of different crop rotations on the content and the quality of humus was examined in two long term field experiments in Bavaria, South Germany. The three and five years crop rotations differed in the utilization of grass clover swards (cutting or mulching), in the following crops (potatoes or barley) in the portion of grass clover swards (33 and 40 %) and in the legume art (grass clover or grain legume). The soil samples were taken in 1998 (beginning of the trials), in 2010 and in 2013 and were analyzed for Corg and Nt.
The development of the Corg- and Nt-contents was better in the crop rotations with grass clover swards (increasing) than in the crop rotation with grain legume (rising or unchanged,). With one exception, no differences were determined between the crop rotations with grass clover swards concerning the development of these contents.