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Below ground biomass carbon

Roots are a long term and stable carbon sink, accounting for about 0.4 of the above ground biomass across biogeographical regions. Well established and developed root systems provide various ecosystem services related to improved soil quality (higher cation exchange capacity and nutrient turnaround) and characteristics (improved soil porosity and aeration). Spatially explicit data and assessments of forest biomass and carbon are paramount to design and implement effective sustainable forest management options and forest related policies. The belowground biomass carbon index (BBCI) presented in this dataset is expressed in Mg (Megagrams or Tonnes) of carbon per km2. It represents an estimation of the carbon stored in the roots of all living trees. Together with the above-ground carbon index (AGCI) and the soil organic content index (SOCI), it provides a complete overview of the total carbon stored in forest areas (trees and soil).

Santoro, M., Cartus, O., Mermoz, S., Bouvet, A., Le Toan, T., Carvalhais, N., Rozendaal, D., Herold, M., Avitabile, V., Quegan, S., Carreiras, J., Rauste, Y., Balzter, H., Schmullius, C., Seifert, F.M., 2018, GlobBiomass global above-ground biomass and growing stock volume datasets, available on-line at OR Santoro, M. et al. (2018): GlobBiomass - global datasets of forest biomass. PANGAEA,


*** The belowground biomass carbon is the carbon stored in tree roots; only added to the soil organic carbon does it represent the total belowground carbon stock. ***The biomass to carbon conversion factor of 0.5 used is a good approximation of the typical carbon content in the biomass of terrestrial vegetation, and is consistent with the Good Practice Guidance in LULUCF by the IPCC (2003). There is however some variation for different tree species, different components of a tree or a stand and age of the stand, which may be accounted for in more detailed assessments. ***The IPCC Root-to-shoot ratios depend on the biogeographic conditions (ecozone), forest type, forest origin (natural or planted) and aboveground biomass density. However, while the biomass map provides wall-to-wall global coverage, the IPCC ratios are not available for all existing combinations of the parameters indicated above. In order to estimate the root-to-shoot ratios in the classes not represented in the IPCC table, the following assumptions were made: 1. Missing ecozones in the IPCC table: use the ratio for the most similar ecozone included in the IPCC table. The similarity considers the way trees allocate biomass in the belowground component (i.e., higher ratios for dry ecozones); 2. Missing Continent for a certain ecozone in the IPCC table: use the average ratio available for other continents located in the same ecozone and same biomass class (if appropriate); 3. Missing Origin in the IPCC table: use the ratio for the same Forest type but different forest origin(if available); 4. Missing Forest type: use the ratio for the same (or most similar) Forest type but different Origin (if available); 5. Missing AGB class: use the ratio for any available AGB class under the same conditions (if available). ***For more information, refer to:

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