the National Natural Science Foundation of China (42407080)

Nitrogen pollution from agricultural and urban stormwater runoff is a growing problem, and stormwater Best Management Practices (BMPs) to combat nonpoint source pollution are ineffective in removing nitrogen.Best Management Practices (BMPs) for non-point source pollution are ineffective in removing nitrogen, and insufficient denitrification is the main problem.This project proposes to use pyrite and biochar composites to construct a novel autotrophic-heterotrophic synergistic denitrification system and apply it to BMPs toenhance their nitrogen removal capacity.To investigate the effects of material preparation and reaction conditions on denitrification; to carry out denitrification kinetic study, monitor the nitrogen balance and by-products during denitrification, analyze the microbial community structure and functional genes, and explore the role of pyrite-heterotrophic BMPs in denitrification. We also carried out denitrification kinetic studies to monitor the nitrogen balance and by-products during denitrification, analyze the structure and function of the microbial community, and explore the mechanism of denitrification and denitrification by synergistic denitrification of pyrite-biochar.The pyrite-biochar composite was applied to BMPs to test its nitrogen removal effect on stormwater runoff.