Method of integrated fertilizer management adapted to the azotobacterial treatment of soil borne cellulosic crop residues and catch crops (cipan) comprising the formation of an elementary indicator of the resilience of the bacterial fraction of the microflora of an arable soil in terms of diversity, activity and/or abundance when confronted with variations in the pH of the surrounding soil characterized in that the formation of the indicator elementary, iSAB (elementary indicator of the acid-base resilience of indigenous telluric azotobacteria challenged by ΔpH), is obtained directly using pre-established relationships, namely; • a first relationship [ΔpH:: pH] quantitatively representing the acid-base defiance of the soil, DEF (acid-base defiance of a soil with regard to azotobacterial populations it shelters) formally defined as the ratio between the amplitude of the exchangeable acidity (ΔpHo - ΔpHn) and the ΔpH associated with the pHo (ΔpHo) and obtained by the first derivative equal to 0.00 of the relation [ΔpH:: pH] on the basis of soil pH values, preferably the water pH to ensure a ΔpH (aka exchangeable acidity of the soil attributable to aluminum and hydrogen adsorbed on the soil exchange complex but exchangeable by other cations such as K + and / or Ca ++) measurable (ΔpHi; ΔpH average of a set of ΔpH based on the difference pH water - pH KCl (or pH CaCl2) measured by the user) taken over time or resulting from different cultural practices or from spatial variations listed in various existing databases, knowing that ΔpHo is the optimal ΔpH corresponding to the first zero derivative (0,00) of the relationship [ΔpH:: pH] and ΔpHn the minimum ΔpH of a set of ΔpH, • a second relationship [ngaBAC:: pH] quantitatively representing the acid-base resilience of the native soil azotobacteria, RES(acid-base resilience of native soil azotobacteria faced with pH variations up to ΔpH = [pH water - pH KCl] or even [pH water - pH CaCl2]) defined as the ratio between the effective ΔpH (ΔpHe) and ΔpHi, ΔpHe being detectable as soon as ngaBAC (number of bacterial cells ( n), their masses (g) and/or their abundances relative to those of other fractions of the soil microflora, their genomic and / or phenotypic diversity and/or their metabolic and/or catabolic activities) is appreciably affected by ΔpH when the minimum of a certain confidence interval (ic) of the aforementioned fixed curve crosses (intersects) the maximum of the ic of the aforementioned variable curve at the point "pi", • the superposition, graphical or mathematical, with respect to ΔpHi = [pH water - pH KCl], of these two relationships - DEF and RES, to obtain the difference iSAB = [DEF - RES] as an elementary indicator of the degree of acid-base resilience of azotobacterial populations native to the soil, • and finally, the integration of iSAB into an aggregate index of eAZB used to calculate the forecast doses of nitrogen fertilizers (dN) adapted to the functioning of such azotobacterial treatment of cellulosic crop residues in integrated fertilizer management. • a first relationship [ΔpH:: pH] quantitatively representing the acid-base defiance of the soil, DEF (acid-base defiance of a soil with regard to azotobacterial populations it shelters) formally defined as the ratio between the amplitude of the exchangeable acidity (ΔpHo - ΔpHn) and the ΔpH associated with the pHo (ΔpHo) and obtained by the first derivative equal to 0.00 of the relation [ΔpH:: pH] on the basis of soil pH values, preferably the water pH to ensure a ΔpH (aka exchangeable acidity of the soil attributable to aluminum and hydrogen adsorbed on the soil exchange complex but exchangeable by other cations such as K + and / or Ca ++) measurable (ΔpHi; ΔpH average of a set of ΔpH based on the difference pH water - pH KCl (or pH CaCl2) measured by the user) taken over time or resulting from different cultural practices or from spatial variations listed in various existing databases, knowing that ΔpHo is the optimal ΔpH corresponding to the first zero derivative (0,00) of the relationship [ΔpH:: pH] and ΔpHn the minimum ΔpH of a set of ΔpH, • a second relationship [ngaBAC:: pH] quantitatively representing the acid-base resilience of the native soil azotobacteria, RES(acid-base resilience of native soil azotobacteria faced with pH variations up to ΔpH = [pH water - pH KCl] or even [pH water - pH CaCl2]) defined as the ratio between the effective ΔpH (ΔpHe) and ΔpHi, ΔpHe being detectable as soon as ngaBAC (number of bacterial cells ( n), their masses (g) and/or their abundances relative to those of other fractions of the soil microflora, their genomic and / or phenotypic diversity and/or their metabolic and/or catabolic activities) is appreciably affected by ΔpH when the minimum of a certain confidence interval (ic) of the aforementioned fixed curve crosses (intersects) the maximum of the ic of the aforementioned variable curve at the point "pi", • the superposition, graphical or mathematical, with respect to ΔpHi = [pH water - pH KCl], of these two relationships - DEF and RES, to obtain the difference iSAB = [DEF - RES] as an elementary indicator of the degree of acid-base resilience of azotobacterial populations native to the soil, • and finally, the integration of iSAB into an aggregate index of eAZB used to calculate the forecast doses of nitrogen fertilizers (dN) adapted to the functioning of such azotobacterial treatment of cellulosic crop residues in integrated fertilizer management.