Evaluating the impact of manure application timing on corn uptake and losses of nitrogen

Thumbnail Image
Nagasawa, Jason Masahiro
Journal Title
Journal ISSN
Volume Title
University of Guelph

The agronomic value of livestock manures as a nitrogen (N) source and the potential environmental losses of N in corn ('Zea Mays' L.) production were compared over different manure types, application rates and the times of application throughout the year. Corn N-uptake response to spring applications of liquid hog manure (LHM) and liquid cattle manure (LCM) were greater than the late-summer and fall applications. Spring applications of LHM and LCM had an increased proportion of N recovered than the late-summer and fall applications. A pulse of mineral N after the late-summer and fall applied LHM and LCM was found at lower soil depths indicating that the reduction in N recovery may be attributed to leaching losses. Solid poultry manure (SPM) and solid cattle manure (SCM) had a greater proportion of N as organic-N. Since the late-summer and fall applications were greater in N-uptake than the spring applications, this may be due to the mineralization of the organic N. No increases in mineral N concentrations at lower depths were detected for each manure type over the application times. The proportion of available mineral N present within manure types may more directly affect the potential for livestock manures to serve as an N source. Environmental losses of manure N due to application timing may be a function of the proportion of manure as mineral N and seasonal conditions associated with application times. In particular, applications during seasonal patterns of downward water movement increase the potential for mineral N leaching to lower soil depths and to groundwater sources.

manure application, timing, corn uptake, nitrogen, leaching losses