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Updated: Jul 8, 2025

Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors

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Published on: December 6, 2018

与颗粒相关的脱是有氧沿海水域N₂O的主要来源

Xianhui S Wan^1,2, Hua-Xia Sheng³, Li Liu³

¹College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China. xianhuiw@princeton.edu.

Nature communications

|December 13, 2023

概括

沿海海洋会产生大量的氧化 (N2O). 脱,而不是氨氧化,是含氧水中的主要N2O来源,受营养物质和颗粒物的影响.

科学领域:

海洋生物地质化学海洋生物地质化学
环境微生物学环境微生物学

背景情况:

沿海海洋是大气中氧化 (N2O) 的重要来源.
了解N2O生产途径对于全球N2O预算评估至关重要.
人类活动严重扰乱这些环境,影响N2O排放.

研究的目的:

调查推动人类影响的沿海海洋中N2O生产的关键过程.
通过河口-沿海梯度识别N2O的主要微生物来源.
了解粒子和营养素在调节N2O流量的作用.

主要方法:

用同位素标记实验来追踪N2O生产途径.
进行了尺寸分成的操纵实验,以分离微生物群落.
基因分析用于识别氨氧化剂和脱剂.
在不同的基板和颗粒度下测量了N2O生产率.

主要成果:

多种过程有助于沿河口-沿海梯度生产N2O.
脱化被确定为氧气充足的沿海水域中占主导地位的N2O来源,与此前的假设相反.
氨氧化在小颗粒上更为显著,而脱化在大颗粒上占主导地位.
N2O生产率与基质和颗粒度正相关.

结论:

脱是沿海海洋系统中一个关键的,被忽视的N2O来源.
微生物N2O生产者的利基分区存在于粒子大小之间.
营养素和颗粒物的可用性是沿海N2O生产的关键调节因素.
这些发现有助于理解涉及人类活动和沿海海洋的气候反循环.

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