Die Bedeutung des Strohgehaltes für die Erhaltung des Stickstoffs während der Kompostierung von Rindermist

The significance of straw content for the rentention of nitrogen during the composting of cattle manure A mixture of cattle manure (low in straw content) and straw were held at room temperature in perforated cubic containers for a 5 month's composting period. The influence of the availability of carbon on the formation of organically bound nitrogen was examined. For this purpose the added straw was reduced in size to varying degrees. The prepared mixtures all contained the same C/N-ratio. Nutrient losses in liquid form could be avoided by careful addition of water. During the first 6 weeks the content of organically bound nitrogen increased, in the sequence of increasing proportions of milled straw, from 6 to 23 %. This was attributed to the increased availability of carbon. At the end of the experiment the content of organically bound nitrogen, in all mixtures, decreased again to the initial level. This was attributed to an extensive mineralisation into nitrate in the mixtures with straw chaff. It is assumed that the low nitrate content of the variant containing only powdered straw is caused by temporary anaerobic conditions, which may be have induced a denitrification.