Publication Date:
2018-03-06
Description:
Much concern has been raised about the increasing threat to air quality and human health due to ammonia (NH 3 ) emissions from agricultural systems, which is associated with the enrichment of reactive nitrogen (N) in southern Asia (SA), home of more than 60% the world's population (i.e., the people of West, central, East, South, and Southeast Asia). Southern Asia consumed more than half of the global synthetic N fertilizer and was the dominant region for livestock waste production since 2004. Excessive N application could lead to a rapid increase of NH 3 in the atmosphere, resulting in severe air and water pollution in this region. However, there is still a lack of accurate estimates of NH 3 emissions from agricultural systems. In this study, we simulated the agricultural NH 3 fluxes in SA by coupling the Bidirectional NH 3 exchange module (Bi-NH 3 ) from the Community Multi-scale Air Quality model with the Dynamic Land Ecosystem Model. Our results indicated that NH 3 emissions were 21.3 ± 3.9 Tg N yr −1 from SA agricultural systems with a rapidly increasing rate of ~0.3 Tg N yr −2 during 1961−2014. Among the emission sources, 10.8 Tg N yr −1 was released from synthetic N fertilizer use, and 10.4 ± 3.9 Tg N yr −1 was released from manure production in 2014. Ammonia emissions from China and India together accounted for 64% of the total amount in SA during 2000−2014. Our results imply that the increased NH 3 emissions associated with high N inputs to croplands would likely be a significant threat to the environment and human health unless mitigation efforts are applied to reduce these emissions.
Electronic ISSN:
2471-1403
Topics:
Geosciences
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
,
Medicine
