FOREST HARVESTS AND WOOD PRODUCTS - SOURCES AND SINKS OF ATMOSPHERIC CARBON-DIOXIDE

Changes in the net carbon (C) sink-source balance related to a country 's forest harvesting and use of wood products is an important componen t in making country-level inventories of greenhouse gas emissions, a c urrent activity within many signatory nations to the UN Framework Conv ention on Climate Change. We propose two approaches for estimating nat ional C inventories from forest harvesting and wood product utilizatio n (excluding forest regrowth): the atmospheric-flow method and the sto ck-change method. The former has the atmosphere as its system of inter est and counts ail flows to and from the atmosphere for a particular c ountry. The latter looks at a country's forest and wood product C stoc ks and how they change over time. Here we develop these two methods, a nd estimate national C source-sink balance from the readily available FAO global forest products database for countries, regions, and the wo rld. Both methods gave a worldwide estimated source of 980 Tg of C: in 1990 as a result of forest harvests and wood product utilization; abo ut 60% came from developing countries and 40% from developed countries . Estimates (Tg C) for selected developing countries for the atmospher ic-flow/stock-change method were: Brazil, 72/73; India, 81/80; Indones ia, 53/56; and Ivory Coast, 3.9/4.3; and for selected developed countr ies (again atmospheric-flow/stock-change method): Canada, 36/50; Finla nd, 8.8/13; New Zealand, 2.7/3.4; and United States 141/138. Net wood exporters show lower numbers in the atmospheric-flow method, net wood importers in the stock-change method. Among the variables that most co nsistently and strongly affected C emissions for a given country in 19 90 were: roundwood production, slash left to oxidize, and commodity wo od put into uses greater than or equal to 5 yr. We conclude with a dis cussion that shows how choosing either one of the two methods for wood harvest accounting has potential policy implications or impacts on th e incentives or disincentives to use wood.