Chiang Mai Journal of Science

       Nitrification, a crucial step in nitrogen cycle of ecosystems, is an important issue that attracts many attentions. In this research, the nitrification process is investigated by developing a new dynamical model which couples the kinetics of ammonia oxidation process and nitrite oxidation process. With the application of literature-based parameter values, the dynamical characteristics of nitrification process in aquatic and soil environments are studied. Stable coexistent equilibrium, periodic oscillations, as well as more complex nitrification dynamics, such as quasiperiodic and chaotic oscillations, are predicted in both environments under seasonal variations. The projected levels of ammonia and nitrite ions are similarly aligned with previously reported observations in natural ecosystems. By uncovering the dynamical complexity of nitrification process, this research can advance our comprehension of the nonlinear mechanisms underlying microbial nitrification in ecosystems.