Modeling the Biodegradation of Bacterial Community Assembly Linked Antibiotics in River Sediment Using a Deterministic-Stochastic Combined Model.

To understand the interaction between bacterial community assembly and the assembly linked antibiotics biodegradation, a unique model framework containing a Monod kinetic, a logistic kinetic, and a stochastic item was established to describe the biodegradation of bacterial community assembly linked sulfamethoxazole (SMX) in river sediment. According to the modeling results, both deterministic and stochastic processes driving bacterial population variations played important roles in controlling SMX biodegradation, and the relative importance depended on the in situ concentration of SMX. A threshold concentration of SMX, which was biodegraded in the experimental river sediment depending on different processes, was obtained (i.e., 20 μg/kg). The higher introduced concentration of SMX (>20 μg/kg) was found to promote the acclimation of antibiotic degradation bacteria in microbial community through niche differentiation, which resulted in the specific microbial metabolization of SMX. In contrast, the lower int...