The U.S. Pork Center of Excellence offers a variety of fact sheets explaining the science behind odor and manure management techniques via the Pork Information Gateway Web site’s Environmental Stewardship domain. Erin Cortus, assistant professor, South Dakota State University Department of Agricultural and Biosystems Engineering, maintains this section of the Web site.

She says an increasing world population means waste handling practices will need to continue to improve, while at the same time a higher population will also demand more protein production, which will result in more livestock manure to handle. “What happens to the manure after it is deposited, through storage, treatment or land application, can have significant implications on air quality, water quality, public perception and cost of production,” she says.

Cortus points out that a manure storage system is a living organism that reacts to the manure quality and quantity, weather conditions, with temperature, air speed, pressure all playing a role, and design and management considerations such as structure type, cleaning and maintenance schedules. “These differences make it difficult to provide individualized emission estimates based on limited research data or model nutrient transformations,” she says.

Cortus adds that an additional challenge comes from the fact that manure is often a taboo subject and a “Not-In-My-Backyard” issue. “Manure has an odor. Manure will release many different types of gases. To stop this is to stop natural processes like urea hydrolysis, aerobic and anaerobic digestion. However, by understanding what these processes are, what the main factors are, and then addressing these main factors, we not only promote a better understanding of what manure is, but how to reduce the nuisance associated with it,” she relates.

The challenges associated with manure are many, and require a multi-disciplinary set of scientists to address. Cortus says the information provided at the Pork Information Gateway Web site places a significant emphasis on methods for reducing the environmental impact and effects behind manure management techniques. Read manure management fact sheets and learn more at