Neotrinia splendens (Liliopsida: Poaceae) Growth Influences Spatial Distribution of Soil Bacterial Community in a Degraded Temperate Grassland

<i>Neotrinia splendens</i> is widely distributed and is the dominant plant species of temperate degraded grassland in Inner Mongolia, showing a community growing habit forming a ring of individuals. However, there is a lack of attention to the soil microbial communities inside the ring (IN), outside the ring, and under the <i>N. splendens</i> ring (UN). This study investigated the soil bacterial community composition in three different zones of the <i>N. splendens</i> ring using amplicon sequencing technology, as well as soil environmental variables. The soil physicochemical properties, the composition of soil bacterial community, and the soil bacterial α-diversity varied significantly among the three zones. Especially, the growth of <i>N. splendens</i> promotes the soil bacterial diversity in the UN zone due to the interactions between plant and soil microbes. Soil NO₃^--N, TC, TN, and pH are the key factors causing the variations of soil bacterial community composition and bacterial diversity. Proteobacteria and Actinobacteria phyla of microorganisms accounted for the largest proportion in network analysis among the three zones. Overall, attention should be paid not only to the improvement of grassland vegetation and soil quality but also to the change in soil microorganisms during the formation and expansion of the <i>N. splendens</i> ring in the future.