Cost Effective Strategy to Reduce Nitrogen Loss from Land Application of Dairy Manure

Dr. Jennifer Becker is the PI. The purpose of this project is to (1) evaluate the effectiveness of conservation tillage manure applicators at reducing ammonia volatilization from land applied dairy manures in conservation tillage systems in the Mid-Atlantic region and to demonstrate their cost effectiveness, labor requirements, utility for ammonia reduction and improved manure and nutrient management, and (2) effectively disseminate this information to agricultural producers, consultants, regulators, extension personnel, and other interested parties in the Mid-Atlantic region.

This integrated research and extension project is a collaborative undertaking with the Maryland Department of Agriculture and Dr. John J. Meisinger (United States Department of Agriculture-Beltsville Agricultural Research Center) and is funded by a grant from the Chesapeake Bay Trust. Field studies will use micro-meteorology and wind tunnels to compare ammonia volatilization and changes in soil nitrogen (N) levels following surface application of dairy manure both with and without conservation and conventional tillage. The information from these studies will be used to estimate the impact of reducing ammonia volatilization on supplemental fertilizer requirements.

The costs associated with implementing the use of conservation tillage manure application, including management and labor costs, will be estimated along with potential corn crop yield benefits. The extension component of this project includes workshops and on-farm demonstrations, which will summarize the results of the field research studies and demonstrate manure being applied using different technologies and equipment, including conservation tillage incorporators. In field measurements of ammonia emissions during these demonstrations will illustrate the effects of manure application techniques on ammonia emissions and N conservation. Land application approaches for reducing ammonia emissions will be discussed in the context of whole farm management and opportunities for conserving N at other management stages will also be presented.

Preliminary field experiments showed that loss of soil N following surface application of dairy manure was lower when manure was incorporated using a conservation tillage applicator (Aerway) compared with surface application alone. Use of the conservation tillage incorporator also reduced ammonia emissions compared with surface application alone, while increasing surface residues relative to the use of conventional tillage. Over 200 dairy producers, soil conservation district personnel, and nutrient management and other extension personnel have been educated about the use of conservation tillage manure applicators to reduce ammonia and odor emissions through three on-farm demonstrations in 2007.

For more information, contact Dr. Jennifer Becker

Last updated: 02/7/2008