Response of nitrogen removal processes in estuarine sediments to environmental changes during sea ice freezing and melting

Freezing and thawing of sea ice is constantly changing the complex aquatic environment of estuaries and putting great pressure on microbial nitrogen cycling in coastal ecosystems. However, the overall impact of sea-ice-induced environmental changes on microbial nitrogen removal processes in estuaries is unclear. Here, we simulated the freezing and thawing of sea ice and investigated the response mechanism of microbial denitrification processes in estuarine sediments to sea ice by combining 15N labeling and molecular techniques.