- Azotobacterial fertilization method for reducing soil-based emissions of nitrous oxide and enriching soil-borne cellulosic crop residues with P & S in order to promote their use as carbonaceous substrates in the presence of field cereal crops, rapeseed and/or intermediate nitrate catch-crops (cipan) planted after burial of these crop residues comprising mineral or organic fertilizers of N (nitrogen) of P (phosphorus) and / or S (sulfur) either applied pre-harvest to the aerial parts of an agronomic crop always on feet producing cellulosic soil-borne crop residues, or post-harvest directly to said cellulosic soil-borne crop residues by the aforementioned agronomic crop, wherein; • the hectare rates of N, P and S fertilizers when applied pre-harvest to the aerial parts of the agronomic crop still standing producing these cellulosic crop residues left in the ground post-harvest are higher than those normally recommended, and the growth stages (BBCH; scale of the growth stage of the crop for the application of fertilizers to the foliage) at the time of their more advanced applications, than those normally recommended in foliar fertilization associated with apparent coefficients of use (UE; apparent coefficient of use indicating the proportion of the nutrient concerned - N, P or S, applied as fertilizer and found in the grains) optimal of these fertilizers N, P and S, and also wherein; • the hectare doses of fertilizers N, P and S when applied directly to the soil-borne crop residues post-harvest of the aforementioned agronomic crop producing them are equal to or up to 50% more or less important compared to those applied pre-harvest than to the aerial parts always on feet of agronomic crops producing these crop residues, and in which; • the above-mentioned doses-hectare of the aforementioned mineral or organic fertilizers of N of P and / or S applied pre-harvest to the aerial parts still standing of the agronomic crop producing and thus leaving cellulosic crop residues in the soil are higher from 5 to 50%, more particularly from 10 to 33%, or preferably 25% compared to those normally recommended in foliar fertilization in order to optimize their apparent coefficients of use, and • that the aforementioned growth stages (BBCH) are more advanced from 5 to 33%, more particularly from 10 to 25% and preferably 20% compared to those normally recommended in foliar fertilization N, P and S in order to optimize their apparent coefficients of use. • the hectare rates of N, P and S fertilizers when applied pre-harvest to the aerial parts of the agronomic crop still standing producing these cellulosic crop residues left in the ground post-harvest are higher than those normally recommended, and the growth stages (BBCH; scale of the growth stage of the crop for the application of fertilizers to the foliage) at the time of their more advanced applications, than those normally recommended in foliar fertilization associated with apparent coefficients of use (UE; apparent coefficient of use indicating the proportion of the nutrient concerned - N, P or S, applied as fertilizer and found in the grains) optimal of these fertilizers N, P and S, • the hectare doses of fertilizers N, P and S when applied directly to the soil-borne crop residues post-harvest of the aforementioned agronomic crop producing them are equal to or up to 50% more or less important compared to those applied pre-harvest than to the aerial parts always on feet of agronomic crops producing these crop residues, • the above-mentioned doses-hectare of the aforementioned mineral or organic fertilizers of N of P and / or S applied pre-harvest to the aerial parts still standing of the agronomic crop producing and thus leaving cellulosic crop residues in the soil are higher from 5 to 50%, more particularly from 10 to 33%, or preferably 25% compared to those normally recommended in foliar fertilization in order to optimize their apparent coefficients of use, and • that the aforementioned growth stages (BBCH) are more advanced from 5 to 33%, more particularly from 10 to 25% and preferably 20% compared to those normally recommended in foliar fertilization N, P and S in order to optimize their apparent coefficients of use.