Test of a mathematical model for degradation kinetics of components of cultivated soil. Its use to determine optimal nutrient dosage required to maintain stable soil conditions

In a previous paper, the structural characteristics of a mathematical model describing the kinetics of change in the fundamental soil components activated by organic matter added to the soil (perturbation) were illustrated. An initial partial verification of the model was also provided. In the present study, the results of more complete tests of this model obtained with the use of kinetics, from three different experimental works, regarding the microbial biomass, carbon, total and inorganic nitrogen are reported. By applying small corrections to two of the five model equations, a better fit of the theoretical curves to the experimental data was obtained. Lastly, the possible use of the model to predict the correct input of nutrients necessary to preserve the physico-chemical characteristics of the soils analysed in this study is discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.