Yu-Tao Wang

The response of microbial communities to changes in precipitation can regulate the nutrition cycling of terrestrial ecosystems, but the effect on the structure and interaction of microbial communities and the relationship with environmental factors in arid and semiarid areas are unclear. Here, a field simulation experiment using three precipitation gradients, 50% of normal precipitation (P50), normal precipitation (P100) and 150% of normal precipitation (P150), was carried out in the typical grassland of the Loess Plateau. We applied high-throughput sequencing and network analysis to explore the effect of precipitation changes to soil microbial communities. The results indicated that the structural composition of the microbial community responded to precipitation treatments dramatically. The Top 50 microbials were divided into resource-limited, drought-tolerant and sensitive groups based on their response to altered precipitation. The network of bacteria was more complex and stronger than fungi. Bacterial networks were less stable but more adaptable under drought than fungal. Increasing precipitation promoted the complication and firmness of fungi networks. These findings are crucial for revealing the effects of climate change on soil microbial communities in arid-land and elsewhere and can provide valuable guidance for ecological restoration and response to climate change of the Loess Plateau.

The study evaluates how simulated climate change affects microorganism communities in the desert grassland of Ningxia Autonomous Region, China. It explores the soil microorganism community and relationships among the soil microorganism community, chemical properties, soil respiration (SR), and plant biomass under climate change. We established a field experiment with five levels of rainfall using rainout shelters and two levels of temperature by the Open-Top Chamber (OTC). The results show that in fungal communities, normal precipitation will promote the number and base number of valid sequences the most, and R66 will significantly promote the mean length of the valid sequence. In the bacterial communities, the interaction of increasing temperature and R133 will promote the number of valid sequences and R166 will promote the length of valid sequences. Neither rainfall nor rising temperature promotes not only the soil community α-diversity but also the soil microorganism community β-diversity. Soil microorganism communities show resistance to rainfall. SR will limit the soil microorganism diversity. Soil organic carbon (SOC), soil total nitrogen (STN), and soil total phosphorus (STP) will promote soil microorganism abundance (SMA) and soil microorganism diversity (SMS). Aboveground living biomass (ALB) and soil temperature (ST) will promote soil α-diversity, whereas the effect of root biomass (RB) on the soil α-diversity is the opposite.