ISSN:
1573-0867
Keywords:
ammonium fertilizer
;
application rate
;
cattle slurry
;
denitrification
;
grassland
;
nitrate fertilizer
;
nitrous oxide
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Five field experiments and one greenhouse experiment were carried out to assess the effects of nitrogen (N) fertilizer type and the amount of applied N fertilizer on nitrous oxide (N2O) emission from grassland. During cold and dry conditions in early spring, emission of N2O from both ammonium (NH 4 + ) and nitrate (NO 3 − ) containing fertilizers applied to a clay soil were relatively small, i.e. less than 0.1% of the N applied. Emission of N2O and total denitrification losses from NO 3 − containing fertilizers were large after application to a poorly drained sand soil during a wet spring. A total of 5–12% and 8–14% of the applied N was lost as N2O and via denitrification, respectively. Emissions of N2O and total denitrification losses from NH 4 + fertilizers and cattle slurry were less than 2% of the N applied. Addition of the nitrification inhibitor dicyandiamide (DCD) reduced N2O fluxes from ammonium sulphate (AS). However, the effect of DCD to reduce total N2O emission from AS was much smaller than the effect of using NH 4 + fertilizer instead of NO 3 − fertilizer, during wet conditions. The greenhouse study showed that a high groundwater level favors production of N2O from NO 3 − fertilizers but not from NH 4 + fertilizers. Inereasing calcium ammonium nitrate (CAN) application increased the emitted N2O on grassland from 0.6% of the fertilizer application rate for a dressing of 50 kg N ha−1 to 3.1% for a dressing of 300 kg N ha−1. In another experiment, N2O emission increased proportionally with increasing N rate. The results indicate that there is scope for reducing N2O emission from grasslands by choosing the N fertilizer type depending on the soil moisture status. Avoiding excessive N application rates may also minimize N2O emission from intensively managed grasslands.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00420561
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