Appendix B: Use of Forest Inventories and Geographic Information Systems To Estimate Biomass Density of Tropical Forests: Application to Tropical Africa
S. Brown and G. Gaston
U.S. Environmental Protection Agency, 200 SW 35th St., Corvalis, OR 97333, USA
One of the most important databases needed for estimating emissions of carbon dioxide resulting from changes in the cover, use, and management of tropical forests is the total quantity of biomass per unit area, referred to as biomass density. Forest inventories have been shown to be valuable sources of data for estimating biomass density, but inventories for the tropics are few in number and their quality is poor. This lack of reliable data has been overcome by use of a promising approach that produces geographically referenced estimates by modeling in a geographic information system (GIS). This approach has been used to produce geographically referenced, spatial distributions of potential and actual (circa 1980) aboveground biomass density of all forest types in tropical Africa. Potential and actual biomass density estimates ranged from 33 to 412 Mg/ha (10E06 g/ha) and 20 to 299 Mg/ha, respectively, for very dry lowland to moist lowland forests and from 78 to 197 Mg/ha and 37 to 105 Mg/ha, respectively, for montane-seasonal to montane-moist forests. Of the 37 countries included in this study, more than half (51%) contained forest that had less than 60% of their potential biomass. Actual biomass density for forest vegetation was lowest in Botswana, Niger, Somalia, and Zimbabwe (about 10 to 15 Mg/ha). Highest estimates for actual biomass density were found in Congo, Equatorial Guinea, Gabon, and Liberia (305 to 344 Mg/ha). Results from this research effort can contribute to reducing uncertainty in the inventory of country-level emission by providing consistent estimates of biomass density at subnational scales that can be used with other similarly scaled databases on change in land cover and use.
- Brown, S. and G. Gaston. 1995. Use of Forest Inventories and Geographic Information Systems to Estimate Biomass Density of Tropical Forests: Applications to Tropical Africa. Environmental Monitoring and Assessment 38:157-168.
Copyright 1995 Kluwer Academic Publishers, Printed in the Netherlands. This abstract is provided with permission of Kluwer Academic Publishers.