Nitrogen fixation is generally referred to as any conversion of the (chemically inactive) elementary, molecular nitrogen (N2). It is an important part of the nitrogen cycle. In addition, the fixing of the soil nitrogen in the organic matter is also called nitrogen fixation. This phenomenon, which occurs in an unfavorable carbon-nitrogen ratio (C/N ratio), can be attributed to the nitrogen requirements of degrading microorganisms. If nitrogen-poor mulch material such as sawdust, wood or bark chopping is used, a lack of nitrogen in crop plants can be observed. Therefore, it may be advantageous to compost such materials beforehand or to add a nitrogen fertilizer. With the decomposition of organic matter, the bonded nitrogen is released in the long term.