长期被忽视的化对黄河N2O排放的贡献
Shuo Wang1, Shengjie Li2, Mingfei Ji3
1Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China.
Environmental pollution (Barking, Essex : 1987)
|May 4, 2024
概括
河流是氧化 (N2O) 的重要来源,但微生物过程仍然不清楚. 这项研究揭示了化,而不是脱化,是黄河的主要N2O来源,氨氧化细菌和古生物扮演着关键角色.
科学领域:
- 环境微生物学 环境微生物学
- 生物地质化学生物地质化学
- 河流生态系统 河流生态系统
背景情况:
- 河流对全球二氧化 (N2O) 预算有很大影响.
- 人们对河流中N2O的微生物来源和沉积点的了解很少,这导致人们忽视了化.
- 量化N2O生产和减少途径对于了解河流N2O排放至关重要.
研究的目的:
- 为了研究黄河中N2O的同位素特征.
- 量化微生物N2O生产来源和N2O减少的程度.
- 区分氨氧化细菌 (AOB) 和古菌 (AOA) 对N2O排放的贡献.
主要方法:
- 对N2O同位素特征的分析.
- 量化N2O生产和减少途径.
- 评估溶解有机碳 (DOC) 对脱的影响.
- 区分AOB和AOA对化驱动N2O生产的贡献.
主要成果:
- 无化仅占黄河N2O产量的18.3%,同时减少了50.2%-80.2%.
- 脱率与溶解有机碳 (DOC) 有正相关,但通常受其可用性限制.
- 化成为氧气充足的黄河中主要的N2O贡献者.
- 氨氧化细菌 (AOB) 主导了N2O生产,但氨氧化古生物 (AOA) 贡献了显著的份额 (25.6%的化器产生的N2O).
结论:
- 化是N2O的重要来源,在像黄河这样的大型寡质河流中.
- 溶解有机碳的可用性限制了河流系统中的脱.
- 突出了氨氧化古生物在寡头性河流N2O排放中的重要作用.
- 同位素分析提供了一种有价值的非侵入性方法,用于量化水生环境中的微生物N2O来源和沉.
相关概念视频
Overview of Nitrogen Metabolism
7.9K
Nitrogen is a very important element for life because it is a major constituent of proteins and nucleic acids. It is a macronutrient, and in nature, it is recycled from organic compounds and stored in the form of ammonia, ammonium ions, nitrate, nitrite, or nitrogen gas by many metabolic processes. Many of these metabolic processes are carried out only by prokaryotes.
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
7.9K
The Nitrogen Cycle
52.1K
Nitrogen atoms, present in all proteins and DNA, are recycled between abiotic and biotic components of the ecosystem. However, the primary form of nitrogen on Earth is nitrogen gas, which cannot be used by most animals and plants. Thus, nitrogen gas must first be converted into a usable form by nitrogen-fixing bacteria before it can be cycled through other living organisms. The use of nitrogen-containing fertilizers and animal waste products in human agriculture has greatly influenced the...
52.1K
2° Amines to N-Nitrosamines: Reaction with NaNO2
4.2K
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
4.2K
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
3.3K
Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...
3.3K
Reaction Yield
51.1K
The theoretical yield of a reaction is the amount of product estimated to form based on the stoichiometry of the balanced chemical equation. The theoretical yield assumes the complete conversion of the limiting reactant into the desired product. The amount of product that is obtained by performing the reaction is called the actual yield, and it may be less than or (very rarely) equal to the theoretical yield.
51.1K
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
3.8K
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
3.8K


