Background and aims Soil microbial communities
are crucial for ecosystem functioning, but their sea-sonal responses to climate warming and increased precipitation are poorly understood. This study inves-tigates how soil microbial communities respond to warming and enhanced precipitation across different seasons in a semiarid grassland.
Methods A field manipulation experiment of cli-
mate warming and increased precipitation was con-ducted to assess seasonal variations in bacteria and fungi composition and diversity in a semiarid grass-land of Inner Mongolia. We analyzed bacterial and fungal communities by sequencing the 16S rRNA and ITS regions. ResultsWarming changed asynchronously bacterial composition in each period of growing seasons and increased fungal species richness in early growing season. In contrast to warming, increased precipita-tion differentially changed bacterial and fungal com-position in each period of growing season. Structural equation models showed that warming lowered bac-terial diversity by increasing air temperature in late growing season, but did not change fungal diversity. Increased precipitation limited bacterial diversity by inhibiting soil organic carbon in early growing sea-son and soil moisture, total nitrogen and plant diver-sity in late growing season. Conversely, increased precipitation also increased fungal diversity through enhancing soil pH and plant diversity in early grow-ing season. ConclusionsThese findings demonstrate asynchro-nous responses of microbial community in different seasons to climate warming and increased precipita-tion, with subsequently reconstruct the seasonal pat-tern in microbial communities.