World’s Soil Resources

6.2.4 | Spatial distribution of carbon in biomass
A global map of C stored in biomass following the IPCC Tier 1 approach was produced by the European
Commission Joint Research Centre (Carré at al., 2010; EU, 2004; Hiederer et al., 2010). The C stocks are
determined for above- and below-ground biomass and include dead organic matter for the relevant vegetation
types. The default factors largely follow the IPCC specification, with specific attention given to agricultural
areas. The underlying vegetation data are based on the GlobCover V 2.2 (ESA, 2011). Because the GlobCover data
limits cropland to areas below 57º N in Europe the data were merged with the M 3-Cropland (Ramankutty et
al., 2008) and Crops (Monfreda, Ramankutty and Foley, 2008). In a comparison of the geographic distribution
of IPCC vegetation classes between the GlobCover and the M 3 Cropland and Pasture data, some notable
differences were identified (Hiederer et al., 2010). Some of the differences were attributed to the dissimilar
definition of the vegetation classes in the data sets, although others, such as the separation of shrub land
from open forest or confusion between cropland and pastures, seem to be the result of the classification
algorithm used or of sensor characteristics.
The global biomass map thus generated by the Joint Research Centre (JRC) estimates the storage of C in
the above-ground and below-ground vegetation and dead organic matter to be 456 Pg C. The JRC estimates
are thus 44 Pg C (8.8 percent) lower than those of the ‘New IPCC Tier -1 Global Biomass Carbon Map for the
Year 2000’ (Ruesch and Gibbs, 2008). The difference is not evenly distributed between geographic regions. A
comparison of carbon in C by climatic region is given in Figure 6.5.
Figure 6.5 Distribution of carbon in biomass between ORNL-CDIAC Biomass and JRC Carbon Biomass Map
The graph shows that the ORNL-CDIAC Biomass and the JRC Carbon Biomass map are mostly comparable,
but the JRC map places relatively more C in the biomass in ‘Cool Temperate Moist’ (11.4 percent of the total C
stock in biomass; 51.8 Pg C) and ‘Warm Temperate Moist’ (8.7 percent of the total C stock in biomass; 39.9 Pg
C) climate regions at the expense of other regions. By contrast, the ORNL-CDIAC Biomass map locates only 5.7
percent of the total C stock in biomass (28.4 Pg C) in the ‘Cool Temperate Moist’ and 5.7 percent of the total C
stock in biomass (28.7 Pg C) in the ‘Warm Temperate Moist’ climate region.
For the total terrestrial pool of organic C, biomass is the more important pool only in the climate regions
‘Tropical Wet’ and ‘Tropical Moist’. For all other climatic regions, the soil stores more organic C than the biomass
(Scharleman et al., 2014).
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