Impact of Moderate Grazing on Soil Microbial Communities in Desert and Meadow Steppes of Inner Mongolia
Description
In this study, we employed second-generation amplicon sequencing to analyze the microbial diversity in soils from meadow steppe and desert steppe under grazing and control conditions. Soil samples were collected from a depth of 0-30 cm in August 2022 and were subjected to microbial diversity analysis using 16S rRNA gene sequencing. The microbial diversity, including α-diversity and β-diversity, was calculated to understand the complexity and variation within and between the microbial communities. Differences in microbial communities between treatments were assessed using ANOVA and PERMANOVA methods. Functional predictions of the microbial communities were performed using the PICRUSt2 tool, which allowed us to infer potential microbial functions based on 16S rRNA gene sequences. Functional indices, including carbon cycling functions, were computed to evaluate the ecological roles of the microbial communities. Network analysis was conducted to investigate the interactions within the microbial communities. This analysis revealed the topological properties of bacterial and fungal networks, such as connectivity and centrality. Grazing treatments were found to increase the complexity and centrality of fungal networks while decreasing the connectivity and centralization of bacterial networks. Module network analysis further explored the modular structures within the microbial networks, identifying key functional modules and their responses to grazing. The findings highlight the distinct microbial community responses to grazing in meadow steppe and desert steppe ecosystems, emphasizing the need for tailored grazing management strategies to promote sustainable ecosystem functioning.