[Phylogenetic Processes and Key Driving Factors of Bacterial Communities in Jinze Reservoir]

To investigate the ecological mechanisms of the bacterial response to human disturbance in micro-polluted water ecosystems, we studied the relationship between the environmental factors and bacterial community development in the incoming water and various areas of a reservoir based on an ecological null model. The results showed that the phylogenetic clustering of bacterial communities was more dispersed than expected (the single-sample t-test of SES.MNTD has a 95% lower confidence limit of 9.79). Temperature is an important environmental factor affecting community phylogeny. The relative importance of stochastic and deterministic processes in the bacterial community succession of different samples showed seasonal characteristics. The bacterial community succession in spring, summer, and autumn samples was dominated by random and deterministic processes. NH₄⁺-N is the main environmental factor affecting the relative importance of random and deterministic processes. When the concentration of NH₄⁺-N is 0.06-0.40 mg ·L^-1, the bacterial community succession is dominated by random processes; when the concentration is 0.40-0.80 mg ·L^-1, it is dominated by both random and deterministic processes. Dispersal limitation (61.68%) and heterogeneous selection (26.65%) played important roles in bacterial community changes at different sampling points in the study area.