Venice Lagoon Salt Marsh Microbes Stay Stable Through Day-Night Swings, Supporting Carbon Sequestration

A new study in Microbial Ecology found that microbial communities in Venice Lagoon salt marshes remain compositionally stable over a summer day-night cycle, despite strong swings in temperature and oxygen. Using metabarcoding and metagenomics, researchers showed these microbes rely on functional redundancy and metabolic flexibility rather than community turnover to keep carbon and nutrient cycling running. This stability is good news for blue carbon projects, since restored marshes may develop functioning biogeochemical cycles relatively quickly. The study also highlights the role of sulphur cycling and denitrification in these ecosystems, pointing to how tightly coastal habitat services are tied to microbial activity. Understanding this short-term resilience helps clarify how marshes might respond to longer-term pressures like sea-level rise and pollution, which is critical for conservation and restoration planning.