DEVELOPING SUSTAINABLE CROP AND ANIMAL PRODUCTION SYSTEMS SUITABLE FOR THE SOUTHEAST
Location: Athens, Georgia
Title: Forage management impacts II: Soil quality and nitrogen export in runoff
Submitted to: Soil and Water Conservation Society
Publication Type: Abstract Only
Publication Acceptance Date: July 21, 2007
Publication Date: July 21, 2007
Citation: Butler, D.M., Franklin, D.H., Cabrera, M.L., Steiner, J.L., Risse, L.M., Gaskin, J.W. 2007. Forage management impacts II: Soil quality and nitrogen export in runoff [abstract]. Soil and Water Conservation Society 2007 Annual Meeting, July 22-25, 2007, Tampa, Florida. CD-ROM.
The relationship between indicators of soil quality, water quality and nutrient source needs to be further addressed at the field-scale. Large uncertainties still exist in the magnitude of N losses from forage systems fertilized with animal manures. Quantitative, on-farm evaluations of N losses linked to ecosystem health assessment tools will help us utilize nutrients more efficiently while sustaining farm productivity. Twelve farm fields with forages managed as pasture or hay systems were outfitted with small in-field runoff collectors (SIRCs). Runoff N and Soil N were evaluated from 2000 to 2006 and soil quality indicators were evaluated for years 2002 and 2006. Farm field nutrient management was either inorganic N, broiler litter, dairy slurry or unfertilized. Preliminary results indicated that regardless of nutrient source, NH4+ in runoff was significantly greater in hay fields (P < 0.05). The ratio of NH4+ and total N was however significantly lower for fields fertilized with inorganic fertilizers (P < 0.05). It is expected that farm fields with better soil quality will have reduced incidence of runoff events and runoff losses of N will also be less.