Neue Techniken zur Kompostierung. Teilvorhaben: 11/1. Herstellung und Erprobung eines Organomineralduengers aus aufbereiteten, naehrstoffreichen Ganzpflanzen und vorbehandelten Holzabfaellen mit Klaerschlamm als Zuschlagstoff Abschlussbericht

Scientific status quo: Specification and diversification of secondary fertilizers in order to applicate appropriate nutients to each crop is an propose which is often risen. In horticulture such defined products made out of secondary fertilizers do exist, in agriculture such products have not been developed yet. The objective of the project was given in the formation of a defined fertilizer on bases of sewage sludge composts for application on agricultural plants. To guarantee a high standard of quality, sewage sludges with a minimal content of heavy metals have been chosen. Furtheron the results of the projects 11/2 and 11/3 gave the opportunity to use sewage sludge compost with a minimized content of harmful organic substances. Methods: Different compost processes and different means of confectioning the fertilizers have been examined. The produced fertilizers have been applicated in two field experiments and a greenhouse experiment in various crops. The effects on harvest level and quality of the harvested products have been examined. Results: An optimized production method has been developed. The tested organic-mineral fertilizer had a similar effect like mineral fertilizers on yield level and quality. Organic-mineral fertilizers had no negative effect on the quality of the harvested products. These results led to a certification of theproduced organic-mineral fertilizers by the government authorities. Conclusions: The fertilizer law will be changed within this year. After that, marketing activities for the produced fertilizers and for comparable fertilizers, based on secondary fertilizers, will be launched. (orig.)Available from TIB Hannover: F97B2+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman