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Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/19/2014 Publication Date: 7/14/2014 Citation: Leytem, A.B., Dungan, R.S. 2014. Livestock GRACEnet: A workgroup dedicated to evaluating and mitigating emissions from livestock production. Journal of Environmental Quality. 43(4):1101-1110. Interpretive Summary: Greenhouse gas, ammonia, and particulate emissions from livestock production systems are being increasingly scrutinized by state and federal regulatory agencies. These pollutants, which are also generated by energy, industrial, and transportation sectors, can adversely affect air quality on local, regional, and even global scales. In order to generate a larger database of on-farm emissions, the workgroup ‘Livestock GRACEnet’ was recently created by the USDA and is currently composed of scientists who are located at 13 Agricultural Research Service locations. Based on current needs of livestock producers and policy makers, the objectives of Livestock GRACEnet are to: i) develop emission factors that can reliably be used to estimate emissions from livestock housing and manure storage areas based on species, on-farm management practices, and climactic conditions; ii) develop or improve upon current process-based models to accurately quantify emissions; and iii) identify and develop new management practices to decrease emissions from livestock production systems. This special section highlights some of the work presently being pursued by members of Livestock GRACEnet with the intent of drawing attention to these critical research areas. Technical Abstract: Ammonia, greenhouse gases, and other emissions (e.g., particulate matter, volatile organic compounds, hydrogen sulfide) from livestock production systems are being increasingly scrutinized by regulatory agencies. These pollutants, which are also generated by energy, industrial, and transportation sectors, can adversely affect air quality on local, regional, and global scales. When evaluating the impact of emissions from livestock production on air quality in the United States, ammonia emissions are by far the greatest concern. According to the U.S. EPA it is estimated that 82% of total ammonia emissions are directly related to agriculture, with the majority associated with livestock production. Atmospheric ammonia contributes to the formation of fine particulate matter that is linked to human respiratory problems and its deposition in the environment can lead to the degradation of terrestrial and aquatic ecosystems. While occurring naturally in the atmosphere, the most important greenhouse gases directly emitted during anthropogenic activities are carbon dioxide, methane, and nitrous oxide. In the U.S., livestock production accounts for approximately 4.6% of total greenhouse gas emissions when weighted by their relative contribution to global warming. The generation of dust from livestock housing units has also been linked to ambient air quality issues. Agriculture is estimated to contribute 33% of total anthropogenic fine particulate matter, with livestock operations at about 1.1% of total. In order to generate a larger database of on-farm emissions, collaboration at the national level is necessary. To facilitate this collaboration, the workgroup ‘Livestock GRACEnet’ was recently created by the USDA and is currently composed of scientists who are located at 13 Agricultural Research Service locations. Based on current needs of livestock producers and policy makers, the objectives of Livestock GRACEnet are to: i) develop emission factors that can reliably be used to estimate emissions from livestock housing and manure storage areas based on species, on-farm management practices, and climactic conditions; ii) develop or improve upon current process-based models to accurately quantify emissions; and iii) identify and develop new management practices to decrease emissions from livestock production systems. This special section highlights some of the work presently being pursued by members of Livestock GRACEnet with the intent of drawing attention to these critical research areas. |
