Biomass of the North American boreal forest: a step toward accurate global measures

• Published in: Biogeochemistry 1990-03, Vol.9 (2), p.161-174
• Main Authors: Botkin, D.B, Simpson, L.G
• Format: Article
• Language: English
• Subjects: aerial photography; Animal and plant ecology; Animal, plant and microbial ecology; biogeochemical cycles; Biological and medical sciences; Biomass; biomass production; Boreal forests; Carbon cycle; carbon dioxide; Carbon sequestration; climate change; environmental factors; Forestry; Fundamental and applied biological sciences. Psychology; Global carbon budget; mapping; Shrubs; Synecology; Terrestrial ecosystems; Trees; Tropical forests; Vegetation
• ISSN: 0168-2563; 1573-515X

Field measures of tree and shrub dimensions were used with established biomass equations in a stratified two-stage cluster sample design to estimate the above-ground ovendry woody biomass of the North American boreal forest. The forest boundaries and sampling strata were defined using several environmental factors. The biomass averaged 4.18 ± 1.01 (95% C.I.) kg/m2 and totaled 21.5× 109± 5.2× 109 (95% C.I.) metric tons, providing the first statistically reliable estimate of vegetation biomass for any large area of the Earth. Carbon content was calculated to be 1.9± 0.4 kg/m2 and totaled 9.7× 109± 2.3× 109 metric tons. These values are much lower than previous estimates used in analysis of the global carbon budget, which range from 12 to 18 kg/m2 for the above ground biomass and from 5.6 to 7.9 kg/m2 for carbon content. The main reason for this large difference is the biased nature of the earlier estimates. Other reasons for this lower new biomass value and its implications for our understanding of the global carbon cycle are discussed.