Farmyard manure and soil biologcal activity
Under various site conditions it has been observed that farmyard manure (fresh or composted) brings a higher biological activity in soil than mineral fertilization (Bachinger, 1996; Pettersson et al., 1992). If the tests have been carried out under lab conditions (e.g. enzyme activities, microbial biomass) the results could be attributed alone to qualitative characteristics of the soil samples, as the circumstances of the tests have been constant. Under field conditions, however, environmental parameters controlling biological processes are variable, in particular soil temperature. Therefore, we investigated whether the type of fertilizer indirectly by its effect on crop density is able to influence soil temperature and possibly mineralization intensity.
References:
BACHINGER, J. (1996): Der Einfluß unterschiedlicher Düngungsarten (mineralisch, organisch, biologisch-dynamisch) auf die zeitliche Dynamik und die räumliche Verteilung von bodenchemischen und -mikrobiologischen Parametern der C- und N-Dynamik sowie auf das Pflanzen- und Wurzelwachstum von Winterroggen. Diss. Univ. Gießen. Schriftenreihe Bd. 7, Inst. f. biol.-dyn. Forschung, Darmstadt.
PETTERSSON, B.D.; REENTS, H.J.; WISTINGHAUSEN, E.v. (1992): Düngung und Bodeneigenschaften. Ergebnisse eines 32-jährigen Feldversuches in Järna, Schweden. Schriftenreihe: Band 2, Institut für biologisch-dynamische Forschung, Darmstadt.