Simulating Soil Microbial Population Dynamics Under Aerobic and Anaerobic Conditions Using Individual Based Model.

Dynamics of soil microbes would be associated with nutrient cycles in soil. Still, it would be challenging to monitor population of soil microbial organisms. Little effort has been made to simulate population dynamics of soil microorganisms in paddy fields where interaction of aerobic and anaerobic organism would contribute to carbon and nitrogen cycle in soil. The objective of this study was to develop an individual based model (IBM) for simulation of microbial population dynamics in a rice paddy field. The IBM was designed and implemented to calculate population of aerobic and anaerobic microorganisms under given soil and management conditions, e.g., tillage, flooding, drainage and fertilizer application using C#. In the model, soil carbon and oxygen concentration were forced to simulate growth of soil microorganisms under continuous flooding and intermittent irrigation. Population of aerobes and anaerobes under the continuous flooding irrigation condition was 50% and 10% less respectively than those under the intermittent irrigation. This result suggested that the IBM would be useful to provide insight on the effect of crop management on soil microbes in paddy fields, which would help assessment of management approaches for sustainable agricultural practices. Thus, further studies are merited to improve the model for simulation of microbial population dynamics in realistic rice paddy field, which would require comprehensive calibration of the model and extensive measurements of soil microorganism population.