Plants Decrease Network Complexity and Increase Environmental Stability of Microbial Communities, Shifting the Dominant Environmental Controls from Carbon-Related Factors to pH in Newly Formed Wetlands

Soil microorganisms are crucial regulators of wetland ecological functions and are significantly influenced by plants. However, the ecological patterns underlying soil microbial responses to plants during wetland restoration remain poorly understood. Soil samples from sections with and without plants in each wetland were collected to investigate the impact of plants on soil microbial communities using high-throughput absolute quantification sequencing and analysis of soil physicochemical properties. Results showed that environmental drivers exerted stronger effects on microbial communities in areas without plants. Soil microbial networks in areas without plants were more complex and stable, while plants enhanced the contribution of stochastic processes to microbial community assembly. In areas with plants, pH was the most important environmental driver of soil microbial community variations, while organic carbon was the primary driver in areas without plants. Moreover, bacteria exhibited higher sensitivity than fungi to the same environmental variation in both areas with and without plants. In summary, our findings elucidate the responses of soil microbial ecological patterns to plants in newly formed wetlands, while emphasizing that the major environmental drivers of soil microbial communities are influenced by plants. This study provides important implications for enhancing wetland restoration efficiency.