Table 1

Annual and seasonal NPP of the major units of the biosphere, from CASA-VGPM. Ocean color data are averages from 1978 to 1983. The land vegetation index is from 1982 to 1990. All values are in petagrams of carbon (1 Pg = 1015 g). Ocean NPP estimates are binned into three biogeographic categories on the basis of annual average C sat for each satellite pixel, such that oligotrophic = C sat < 0.1 mg m−3, mesotrophic = 0.1 < C sat < 1 mg m−3, and eutrophic = C sat > 1 mg m−3 (21). The macrophyte contribution to ocean production from (38) is not included in the seasonal totals. The vegetation classes are those defined by (37).

Ocean NPPLand NPP
Seasonal
April to June10.915.7
July to September13.018.0
October to December12.311.5
January to March11.311.2
Biogeographic
Oligotrophic11.0Tropical rainforests17.8
Mesotrophic27.4Broadleaf deciduous forests1.5
Eutrophic9.1Broadleaf and needleleaf forests3.1
Macrophytes1.0Needleleaf evergreen forests3.1
Needleleaf deciduous forest1.4
Savannas16.8
Perennial grasslands2.4
Broadleaf shrubs with bare soil1.0
Tundra0.8
Desert0.5
Cultivation8.0
Total48.556.4