ISSN:
1573-515X
Keywords:
NH 0 3 volatilization
;
denitrification
;
grazing
;
spatial heterogeneity
;
translocation
;
nitrification
;
leaching
;
urine
;
feces
;
15N
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Geosciences
Notes:
Abstract The cycling and volatile loss of N derived from cattle urine at upland and lowland sites within the shortgrass steppe of eastern Colorado was studied, using15N-labelled urea as an N source. Losses of NH 0 3 were determined by direct measurement and by difference. Losses were higher from coarse (27% summer, 12% winter) than from fine textured (0–2%) soils. Immobilization and plant uptake of N accounted for significant amounts of added N. Extrapolating our plot measurements to a typical pasture, using spatially and temporally stratified urine deposition data, losses from upland sites were calculated to be 0.016 g N · m-2 · y-1, while losses from lowland sites were negligible. This resulted in an average loss of 0.011 g N · m-2 · y-1 for a pasture divided 70:30 between uplands and lowlands. The loss of urine N calculated assuming no spatial stratification would be sevenfold higher (0.076 g N · m-2 · y-1). Losses of NH 0 3 from urine, animal biomass removal, and NH2O loss totaled only 0.07 g N · m-2 · y-1 , or about 25% of wet deposition input. We calculated a potential loss of NH 0 3 from senescing vegetation of 0.26 g N · m-2 · y-1, an order of magnitude larger than all other losses combined.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02186964
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