Shifts in bacterial communities drive ecosystem multifunctionality under changed precipitation amount and timing in a semiarid grassland

Precipitation amount and timing profoundlyaffect soil microbial communities and ecosystem functions. However,whether alterations in microbial community and its seasonal dynamics affect soilecosystem multifunctionality (EMF) under changed precipitation in different periods of growing season remain incompletely understood.We conducted a manipulation experiment in a semiarid steppe by simulating a 60% increase and decrease in precipitation during the early (April-June), late (July-September), and entire (April-September) growing seasons to explore the effects of changed precipitation amount and timing on microbial communities, and consequent impacts on EMF in June and September.