Influence of soil chemical reaction and crop rotation on the capacity of reddish preluvosoil for free (asymbiotical) - fixing of the atmospheric dinitrogen

Abstract

This paper continues other scientific research (Stefanic and Oprea G., 2010, 2011) aimed to rectify the Waksman and Karunacker method for determining the soil capacity to fix (asymbiotically) atmospheric dinitrogen. Their method ignored that Nt, determined by the Kjeldahl digestion, did not include nitrates, because these volatilized during boiling with concentrated H2SO4. That error, repeated by all specialists until the present, made Feher (1954), and Rippel- Baldes (1955) and others conclude that atmospheric dinitrogen fixation is insignificant in comparison with the symbiotical one. In this paper we present some results concerning the negative influence of soil acidity, crop-rotation and any monocultures on the microbiological process.