7.1. General Description

7.2 CO2 Sequestration from Forest

The “Land-Use Change and Forestry’ sector covers the processes of CO₂ exchange between the biomass sources (forests, grass and other plants, soils, etc.) and the atmosphere. The CO₂ flow exchange from and to the atmosphere is a set of processes, which result from anthropogenic activity. For example, CO₂ sequestration by forests is related to forest management and use of woodlands aimed at industrial timbering. The reforestation of uncultivated lands, aimed at erosion control, also results in CO₂ accumulation in biomass.

CO₂ emissions in the atmosphere are related to thinning and burning of forests to convert them in agricultural lands, and also because of changes in the organic compounds of the soils due to erosion or chemical treatment.

Due to the significant complexity and heterogeneity of the CO₂ removal and emission processes, the revised IPCC Guidelines define several sub sectors, which encompass the following categories:

    A. Changes in Forest and Other Woody Biomass Stocks.

This category includes the processes of woody biomass growing, felling and timbering. As a rule, the net carbon balance is in the direction of CO₂ removal from the atmosphere.

    B. Forest and Grassland Conversion.

These activities aim at the conversion of land for agricultural use for the production of crops and animal breeding.

    C. Abandonment of managed lands.

These are agricultural lands (fields, pastures, plantations, etc.) which resume their initial vegetation cover (woody or grassy).

    D. CO₂ Emissions and Removals from Soil.

This category includes processes and activities that change the organic composition of the soils. Such is the introduction of minerals during soil treatment, erosion process, etc.

    E. Other.

This category includes activities, which also result in changes of CO₂ flows from and to the atmosphere. Such are soil drainage, shifting the cultivation periods of crop farming (mostly in the tropical regions), succession of longer and shorter cultivation periods, flooding due to the construction of hydro technical installations, changes of underground waters due to human interference, etc.

In the 2003 GHG inventory, and also for the preceding years, the net CO₂ removal from category A – “Changes in Forest and other woody biomass stocks” has been determined. CO₂ emissions or removals from the categories B to E mentioned above have not been determined due to the lack of data or lack of the corresponding activities in Bulgaria.