Potential Contributions of Ammonia‐Oxidizing Microorganisms to the Distributions of Nitrous Oxide in the Northern Bering Sea

作者：Jian Liu, Liqi Chen, Minghuang Ling, Yanpei Zhuang, Jiexia Zhang, Wangwang Ye, Youcheng Bai, Jianwen Wen, Man Wu, Liyang Zhan · 发表于：Journal of Geophysical Research Oceans · 年份：2024 · DOI：10.1029/2023jc020677 · 被引用次数：2 · 研究领域：Microbial Community Ecology and Physiology、Marine and coastal ecosystems、Methane Hydrates and Related Phenomena

Abstract Oceanic N 2 O is a major source of atmospheric N 2 O gas and is involved in global warming and ozone depletion. It is thought to be mainly produced by nitrification, denitrification and nitrifier denitrification processes mediated by ammonia‐oxidizing bacteria, ammonia‐oxidizing archaea (AOA) and denitrifying bacteria. The Bering Sea, especially its continental shelf area, is considered a typical source of atmospheric N 2 O. During the 7th Chinese National Arctic Research Expedition (CHINARE2016), the distributions of N 2 O and ammonia‐oxidizing microorganisms (AOOs) in the Bering Sea continental shelf and abyssal basin water were investigated. At a depth of 50∼900 m within the abyssal basin, the in‐situ ammonia oxidation process, particularly performed by AOA, exhibits considerable potential for the formation of supersaturated N 2 O. Meanwhile, beneath the oxygen minimum zone (depth range is approximately 800∼1,000 m), supersaturated N 2 O is primarily driven by mixing processes, while the ammonia oxidation mediated by AOA also contributes to a certain extent. In addition, the N 2 O distribution characteristic exhibits a substantial disparity between the southern and northern Bering Sea shelves, with the former characterized as a mild sink and the latter as a weak source. The water column of the Bering Sea demonstrates a considerable potential for generating supersaturated N 2 O through ammonia oxidation, as corroborated by the current study.