Table 5.2 Seasonal sums and statistics of gross primary production (GPP) at the Mead site,
Nebraska, USA
Year
Crop Type
GPP EC
GPP VPM
GPP %RE
RMSD
2001
Maize
1662.32
1745.81
5.02
2.37
2003
Maize
1592.72
1828.19
14.78
2.66
2005
Maize
1593.92
1744.45
9.44
2.01
2002
Soybean
910.24
913.66
0.38
1.87
2004
Soybean
845.68
830.30
-1.82
1.46
RMSD Root Mean Squared Deviation
GPP EC seasonal sum of GPP estimated from eddy covariance flux tower observations
in g C m
-2 yr
-1
GPP VPM seasonal sum of GPP predicted by the VPM in g C m
-2 yr
-1
GPP %RE: relative error in GPP sums calculated as [(GPP EC -GPP VPM )/GPP EC ] 9 100
Fig. 5.5 Scatterplots between GPP EC and GPP VPM of soybean in individual and multiple years
5 Gross Primary Production of Terrestrial Vegetation
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