Integrated Approach to Mathematical Modelling of Atrazine Degradation in Different Reaction Systems

Abstract

Based on the known approaches and published mathematical models, as well as on theoretical consideration using our experimental data, the integrated approach to mathematical modelling of atrazine biodegradation processes has been employed and sophisticated mathematical models for different reaction systems have been developed. The applicability of these models which take into account physical, chemical, biochemical and biological complexity of atrazine biodegradation was further analyzed in comparison with mathematical models describing simple consecutive reaction systems using first-order kinetics. Kinetics of atrazine degradation in liquid media and soil contaminated with atrazine at the temperatures of 10 and 30 °C was assessed and compared. Biodegradation experiments in liquid media were conducted at atrazine concentrations ranging from 0.14 to 25 mmol/L, while the experiments in soil were conducted at atrazine concentration of approx. 0.44 μmol/g. Computer simulations were applied to explain experimental results and test the adequacy of mathematical models. Detailed analysis of computer simulation data showed that the developed integrated mathematical models could be considered as the most convenient for describing kinetics of atrazine biotransformation in both liquid media and contaminated soil, although even simple mathematical models are suitable for explaining some experimental results, especially when evaluating the temperature effects on biodegradation efficacy of the applied mixed bacterial culture.

Keywords

• atrazine
• biodegradation kinetics
• mathematical modelling
• computer simulation
• mixed bacterial cultures