Improved barn design, cleaning processes and manure treatment could reduce ammonia emissions from commercial dairy cattle barns by 17-50%, according to a new study published in the journal Science of the Total Environment.
The study provides a list of techniques and technologies that could provide the greatest reductions in ammonia emissions, according to an announcement from the International Institute for Applied Systems Analysis (IIASA).
Reactive nitrogen pollution and, more specifically, ammonia pollution have effects on both the environment and human health. Such pollution can lead to algal blooms in fresh water that threaten aquatic wildlife and contribute to smog that damages human health, IIASA said.
"Under the Natura 2000 framework, European Union member countries were requested to regulate their discharge of reactive nitrogen into protected natural ecosystems," said study lead author Luciano Barreto Mendes, a postdoctoral fellow in the IIASA Air Quality & Greenhouse Gases and Ecosystems Services & Management programs. However, "there is a lack of empirical data on how to do this. Our study aimed to assess to what extent management and design technologies could reduce emissions in full-scale commercial dairy cattle cubicle barns."
Mendes and colleagues approached the problem using a model of ammonia emissions that was designed to calculate the ammonia emission reduction potential of new or adapted dairy cattle barns. It incorporates management technologies and processes designed to reduce pollution.
In northwestern Europe, dairy cattle are usually housed loose in large barns, and manure, which is the source of ammonia emissions, is removed and stored in a pit beneath the barn. A number of factors contribute to how much ammonia escapes from the manure into the air, including chemical processes, temperature and airflow.
The new study assesses the emissions reduction potential of a number of techniques, including floor scraping, flushing with water, manure acidification and using different types of flooring.
"Cow manure may not be the most glamorous subject for research, but the fact is that how we deal with waste has a major impact on the health of our environment. This study provides a useful set of interventions that farmers and agriculture policy-makers can use to inform their compliance with EU regulations," Mendes said.