w i n e G R O WIN G
N2O emissions across a given tractor
row area were similar and uniformly elevated mainly after early fall rain events
but also immediately following cultivation. The highest rates of N2O emission
were seen from the tilled cover crop trac-
tor rows, despite the common belief that
tillage will reduce N2O production since
it increases aeration.
Figure 7: Spatial models of emissions after drip fertigation with 7.5 pounds N per acre using KNO3 show how the N2O plume in the drip zone can be quantified spatially. Left panel shows a plume resulting from continuous N application in 20 gallons of fertigation solution over six hours. Right panel shows
effects when nitrogen applied through the drip system was pulsed at hour three, then chased with two hours of irrigation water (REPRINTED WITH
PERMISSION OF THE AMERICAN CHEMICAL SOCIETY, OR, from D.R. Smart et al. N2O emissions and water management in California perennial crops.
pp. 227-255 In Guo, L, AS Gunasekara and LL McConnell (Eds.) Understanding Greenhouse Gas Emissions from Agricultural Management, American
Chemical Society, Baltimore, Md.
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