Progressive Decomposition of Algal Organic Matter Decouples Nitrogen Transformations in Lake Sediments: Evidence from Short-Term Incubation

led to the decoupling of nitrification-denitrification. After 7 days, humic-like AOM dominated by lignins (56.8%) prevailed, reducing oxygen consumption and enabling rapid recovery of nitrification and slow rebound of denitrification. These findings clarify the phased transformations of AOM and their microbial interactions, providing mechanistic insights into the short-term fluctuations of lake water quality and microbial processes during bloom decay.