This Guide covers the calculation of carbon-stock changes in soil and above- and below-ground vegetation due to land use conversion in support of Directive 2009/28/EC on the promotion of the use of energy from renewable sources, particularly for assessing carbon-stock changes due to land conversion for biofuel production.
The methodology put forward is based on the Tier 1 approach as developed under the IPCC Guidelines 2006. It is based on specifying default values for carbon stocks and using coefficients of divergence from the default values according to land use/cover. The methodological approach of the IPCC was adapted for use with spatial layers instead of data tables. The spatial layers of the factors influencing carbon-stock changes were generated with global coverage and thematically aligned to comply with stipulations made in the Directive.
According to the types of land use/cover conversion, a review is made of the methodology of the IPCC (2006). Particular problems regarding peatlands are presented. Drained peatlands cannot be assessed in terms of carbon-stock changes because drainage occurs on the overall peat soil profile (not only on the first 30- cm). This has direct consequences not only on CO2 emissions but also on CH4 and N2O. Tables of coefficients of conversions are then proposed according to climate zone and continental boundaries for soil carbon-stock changes and for above- and below-ground carbon stock changes in biomass in a Technical Annex.