Effects of acidification on nitrification and associated nitrous oxide emission in estuarine and coastal waters.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36914644.
- Also identified by DOI 10.1038/s41467-023-37104-9 and PMC identifier 10011576.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
In the context of an increasing atmospheric carbon dioxide (CO<sub>2</sub>) level, acidification of estuarine and coastal waters is greatly exacerbated by land-derived nutrient inputs, coastal upwelling, and complex biogeochemical processes. A deeper understanding of how nitrifiers respond to intensifying acidification is thus crucial to predict the response of estuarine and coastal ecosystems and their contribution to global climate change. Here, we show that acidification can significantly decrease nitrification rate but stimulate generation of byproduct nitrous oxide (N<sub>2</sub>O) in estuarine and coastal waters. By varying CO<sub>2</sub> concentration and pH independently, an expected beneficial effect of elevated CO<sub>2</sub> on activity of nitrifiers ("CO<sub>2</sub>-fertilization" effect) is excluded under acidification. Metatranscriptome data further demonstrate that nitrifiers could significantly up-regulate gene expressions associated with intracellular pH homeostasis to cope with acidification stress. This study highlights the molecular underpinnings of acidification effects on nitrification and associated greenhouse gas N<sub>2</sub>O emission, and helps predict the response and evolution of estuarine and coastal ecosystems under climate change and human activities.