Table 3. Annual N2O fluxes for three contrasting study sites estimated using either an informed sampling strategy or from daily measurements.
Location† | Best estimate | Informed sampling regime‡ |
|
---|---|---|---|
Annual flux (kg N2O-N ha−1 yr−1) | Annual flux (kg N2O-N ha−1 yr−1) | No. measurements | |
Wongan Hills, Australia. | 0.04 (0.0)a | 0.03 (0.0)a | 60 |
Höglwald, Germany. | 0.58 (0.1)a | 0.64 (0.1)a | 83 |
Bellenden Ker, Australia. | 1.16 (0.1)a | 1.35 (0.2)a | 156 |
Values represent means (and standard errors) of three to five replicates depending on the study site. Values followed by the same letter in the same row are not statistically different (P < 0.05).
†For further details see Table 1. Corresponds to data set numbers 2 (Wongan Hills), 19 (Höglwald) and 28 (Bellenden Ker) in Supplementary Table 1.
‡Informed sampling strategy for each location: Wongan Hills, N2O fluxes measured daily for five consecutive days when daily rainfall > 5 mm rainfall (December–June) or > 10 mm rainfall (July–November); Höglwald, N2O fluxes measured daily for seven days consecutive day when air temperature between −0.7 and 0.7 °C or if daily rainfall > 15 mm; Bellenden Ker, N2O fluxes measured daily for six days consecutive day when daily rainfall > 15 mm.