The fate of slurry-N fractions in herbage and soil during two growing seasons following application

作者：Hoekstra N J^*; Lalor S T J; Richards K G; O'Hea N; Dungait J A J; Schulte R P O; Schmidt O

来源：Plant and Soil, 2011, 342(1-2): 83-96.

DOI：10.1007/s11104-010-0669-7

• N-15 stable isotope tracer
• Grassland
• Cattle slurry
• Residual nitrogen recovery
• Faecal-N
• Urine-N

Farmers are under increasing pressure to use slurry-nutrients more efficiently in order to maximise crop utilisation and minimise losses to the environment. The objective of this field experiment was to quantify the fate of three N fractions (urine-N [U], rapid faecal-N [FR] and slow faecal-N [FS]) from cattle slurry in herbage and soil. The recovery of the three slurry-N fractions was measured in the first and second year after application on a permanent grassland in Ireland. Urine and faeces were collected from cows fed with N-15-labelled herbage, or unlabelled herbage with added N-15-labelled urea and these were recombined to produce differentially labelled experimental slurries. Slurries were applied to plots, and N-15-enrichments of the herbage and three soil layers were determined. The initial recovery of N-15 (6 weeks after application) in herbage was 18%, 13%, 2%, while the residual recovery (12-63 weeks) was 4%, 6% and 7% for U, FR and FS, respectively. The total slurry-N recovery in the plant-soil system was estimated to range from 45% for urine-N to 72% for faecal-N. These results increase our mechanistic understanding of slurry-N dynamics in soil-plant systems and will inform models used to predict the fate of cattle slurry applied to grassland.

• 出版日期2011-5