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Sources, Variations, and Effects on Air Quality of Atmospheric Ammonia

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Purpose of Review As the most abundant alkaline trace gas in the atmosphere, NH3 plays a critical role in the formation of atmospheric particulate matter and nitrogen cycling in ecosystems. NH3 emissions have been increasing globally over the past few decades. To provide a clearer understanding of atmospheric NH3, this paper presents a systematic review of the literature on the sources and variability of atmospheric NH3 and describes the contribution of atmospheric NH3 to PM2.5. Recent Findings (1) The primary source of atmospheric NH3 emissions is agriculture; other sources include combustion-related emissions and volatilization from soil and oceans. However, recent studies have revealed the major role of nonagricultural sources in urban areas. (2) The spatiotemporal variability of atmospheric NH3 is complex, and its mechanisms are not entirely clear. (3) Atmospheric NH3 can participate in multiple atmospheric chemical processes and to the formation of fine particulate matter. Summary This review summarizes the latest knowledge on the sources and variability of atmospheric NH3 and highlights the necessity of controlling atmospheric NH3 emissions. However, significant knowledge gaps still exist in understanding the sources, trends, and effects of atmospheric NH3. Therefore, further research is essential to investigate the influencing factors and environmental effects of atmospheric NH3 concentrations, providing a scientific basis for the development of effective NH3 control strategies.
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Vol:.(1234567890)
Current Pollution Reports (2024) 10:40–53
https://doi.org/10.1007/s40726-023-00291-6
Sources, Variations, andEffects onAir Quality ofAtmospheric Ammonia
ZiruLan1,2· WeiliLin1,2· GangZhao1,2
Accepted: 25 December 2023 / Published online: 19 January 2024
© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024
Abstract
Purpose of Review As the most abundant alkaline trace gas in the atmosphere, NH3 plays a critical role in the formation of
atmospheric particulate matter and nitrogen cycling in ecosystems. NH3 emissions have been increasing globally over the
past few decades. To provide a clearer understanding of atmospheric NH3, this paper presents a systematic review of the
literature on the sources and variability of atmospheric NH3 and describes the contribution of atmospheric NH3 to PM2.5.
Recent Findings (1) The primary source of atmospheric NH3 emissions is agriculture; other sources include combustion-
related emissions and volatilization from soil and oceans. However, recent studies have revealed the major role of nonagri-
cultural sources in urban areas. (2) The spatiotemporal variability of atmospheric NH3 is complex, and its mechanisms are
not entirely clear. (3) Atmospheric NH3 can participate in multiple atmospheric chemical processes and to the formation of
fine particulate matter.
Summary This review summarizes the latest knowledge on the sources and variability of atmospheric NH3 and highlights
the necessity of controlling atmospheric NH3 emissions. However, significant knowledge gaps still exist in understanding
the sources, trends, and effects of atmospheric NH3. Therefore, further research is essential to investigate the influencing
factors and environmental effects of atmospheric NH3 concentrations, providing a scientific basis for the development of
effective NH3 control strategies.
Keywords NH3· Emission source· Variation characters· PM2.5
Introduction
The application of fertilizers has gradually become more
targeted since German scientist Justus von Liebig discov-
ered that NH3 is a key chemical for plant growth [1]. The
Haber–Bosch process, developed by Fritz Haber and Carl
Bosch, has since enabled a rapid increase in NH3 produc-
tion [2]. To promote crop development and maximize yield
when farmland is limited, various fertilizers are produced,
with approximately 80% of NH3 chemical products being
used in these fertilizers, including ammonium nitrate, urea,
calcium nitrate, and ammonium bicarbonate [3]. In recent
years, with countries establishing carbon reduction targets,
the use of synthetic NH3 has expanded to include novel
applications in the energy field; for example, it has been
used in H2 production, in NH3 fuel cells, and in NH3 inter-
nal combustion engines or gas turbines [4]. Currently, the
global emissions of reactive nitrogen have reached unprec-
edented levels, with agricultural NH3 emissions increasing
by 78% over the past 40 years [5]. This increase in emis-
sions highlights the substantial impact of human activities
on the atmosphere and reveals the importance of developing
NH3 emission management strategies. NH3 is a key nitrogen
compound with a substantial effect on the nitrogen cycle in
ecosystems, the formation of atmospheric particulate mat-
ter, and climate change. With its increasing contribution to
nitrogen deposition [6], excessive concentrations of NH3
can cause water eutrophication and soil acidification, lead-
ing to forest soil erosion and reduced biodiversity [79]. In
addition, high concentrations of NH3 in the environment
can also negatively impact ecosystems by directly affecting
plant health through stomatal diffusion [10]. Interactions
involving atmospheric NH3 and other atmospheric compo-
nents have been acknowledged for over a century. NH3 is a
crucial precursor for the formation of secondary inorganic
* Weili Lin
linwl@muc.edu.cn
1 Key Laboratory ofEcology andEnvironment inMinority
Areas, Minzu University ofChina), National Ethnic Affairs
Commission, Beijing100081, China
2 College ofLife andEnvironmental Sciences, Minzu
University ofChina, Beijing100081, China
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Ammonia(NH3) is an inorganic compound, a colorless gas with a strong irritating odor. Agricultural emissions represent one of the primary sources of NH3 in the atmosphere [1][2][3]. Since the 1980s and 1990s, three catalysts have been added to gasoline, increasing NH3 emissions in urban environments. The United States Department of Labor Occupational Safety and Health Administration (OSHA) regulations of indoor NH3 allowable concentration of 50 ppm. ...
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