Table 1 Annual greenhouse gas emissions

From: Carbon-sink potential of continuous alfalfa agriculture lowered by short-term nitrous oxide emission events

Year

N2O flux (mg N2O m−2 y−1)

N2O GWP (g CO2e m−2 y−1)

CH4 flux (mg CH4 m−2 y−1)

CH4 GWP (g CO2e m−2 y−1)

Chamber CO2 flux (g CO2 m−2 y−1)

NEE (g CO2 m−2 y−1)

Total CO2e (g CO2e m−2 y−1)

Eddy Reco (g CO2 m−2 y−1)

Eddy GPP (g CO2 m−2 y−1)

1 (2017–2018)

610.5 ± 68.1 a

181.9 ± 20.3 a

−44.0 ± 2.2 ab

−1.2 ± 0.1 ab

5869.5 ± 31.4 a

−1757 ± 85 a

−1576.3 ± 105.4 a

6485 ± 25 a

8242 ± 96 a

2 (2018–2019)

901.9 ± 74.5 b

268.8 ± 22.2 b

−31.6 ± 2.5 a

−0.9 ± 0.1 a

4135.0 ± 25.4 d

−1989 ± 86 a

−1721.1 ± 108.3 a

6141 ± 22 b

8129 ± 96 a

3 (2019–2020)

777.1 ± 52.0 ab

231.6 ± 15.5 ab

−60.6 ± 2.8 b

−1.7 ± 0.1 b

5217.3 ± 23.9 b

−2942 ± 101 b

−2712.1 ± 116.6 b

6513 ± 27 a

9455 ± 113 b

4 (2020–2021)

263.6. ± 5.6 c

78.6 ± 1.7 c

−78.2 ± 8.8 c

−2.2 ± 0.2 c

4565.2 ± 26.5 c

−2632 ± 93 b

−2555.6 ± 94.9 b

6521 ± 24 a

9153 ± 103 b

All

624.4 ± 27.8

186.1 ± 8.3

−53.5 ± 2.5

−1.5 ± 0.1

4925.9 ± 13.5

−2330 ± 46

−2115.4 ± 54.4

6451 ± 12

8745 ± 51

  1. Mean (± standard error) annual chamber nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) fluxes, 100-year global warming potential (GWP) of N2O and CH4 in CO2-equivalence (CO2e), eddy covariance annual mean net ecosystem exchange (NEE), and annual field-scale CO2e emissions (combination of chamber N2O and CH4 fluxes and eddy covariance NEE) by site year. Net ecosystem exchange (NEE) was derived from ecosystem respiration (Reco) and gross primary productivity (GPP) eddy-covariance measurements. Letters denote statistically significant differences among annual values (p < 0.01) with statistical results reported from one-way repeated measures ANOVAs.
Back to article page