|Powell, J Mark|
Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: June 3, 2008
Publication Date: June 20, 2008
Repository URL: http:////a-c-s.confex.com/crops/2008am/techprogram/P45677.HTM
Citation: Powell, J.M., Russelle, M.P. 2008. Dairy Cattle Management Impacts Manure Nitrogen Collection and Cycling Through Crops [abstract]. American Society of Agronomy Abstracts. Abstract No. P45677. Technical Abstract: Escalating energy and fertilizer N prices, and regulatory limits on ammonia emissions from livestock facilities require methods that reduce manure management costs, enhance the fertilizer value of manure and reduce gaseous ammonia losses. We compared two dairy herd management practices on manure N capture and recycling through crops: the conventional practice of barn manure collection and land-application, and corralling dairy cattle directly on cropland. Cattle were kept either in a barn for two (B2) or four (B4) days and manure hauled to fields, or they were corralled directly on cropland for two (C2) or four (C4) days. Two manure application seasons, spring-summer (SS) and fall-winter (FW) were used each of two years. Each season was followed by three-year crop rotations: SS by wheat-sudangrass-winter rye-corn-winter rye-corn, and FW followed by corn-winter rye-corn-winter rye-corn. Corralling resulted in 50 to 65% greater N applications than barn manure. In-barn N losses (% of excreted N, ExN) were greater from B4 (30%) than B2 (20%). Apparent N recovery of applied N (ANR) by wheat ranged from 13% to 25% at the lower (B2 and C2) N application rates and 8% to 14% at the higher (B4 and C4) N application rates. First corn following FW had ANR of 13 to 32% at the lower (B2 and C2) N application rates and 9 to 20% of applied N at the higher (B4 and C4) N application rates. As percent of ExN, ANR by C2 was 50%, B2 35%, C4 30% and B4 22%. Overall results demonstrate the importance of dairy herd and manure management on ammonia loss, urine N capture and recycling through crops. Corralling returns all ExN resulting in greater N applications and ANR than if cattle are kept in barns and only partial urine N recovery is possible due to ammonia losses.