Extremely dry calcareous soil comammox

In extreme drought conditions, the behavior and activity of complete ammonia oxidizing bacteria (comammox) in calcareous soils are of particular interest due to their role in nitrogen cycling. Calcareous soils, characterized by high pH and calcium content, present unique challenges for microbial communities, especially under water-limited conditions. Comammox bacteria, particularly those belonging to the genus Nitrospira, are known for their ability to oxidize ammonia to nitrite and nitrate in a single step. This capability gives them a competitive advantage over other ammonia oxidizers, such as AOB and AOA, in nutrient-limited environments. In drought conditions, the reduced availability of water and nutrients can significantly impact microbial activity.