Hypoxia and acidification antagonistically suppress nitrification but enhance its N(2)O production in coastal waters.

Hypoxia and acidification together reduce nitrification rates but increase N2O emissions in coastal waters, with combined effects less than additive.

• Why it matters: Understanding how multiple environmental stressors interact is crucial for predicting changes in nitrogen cycling and greenhouse gas emissions in vulnerable estuarine-coastal ecosystems.
• What they did: The study used metatranscriptomic analysis to examine microbial responses across the estuarine-coastal gradient, focusing on nitrification and N2O production under hypoxia and acidification.
• The result: Findings reveal that these stressors disrupt microbial nitrogen cycling, increasing N2O emissions and emphasizing the need to update models to account for multistressor effects on climate feedbacks.