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Edited on Sun Oct-10-10 02:56 PM by jpak
Effects on carbon storage of conversion of old-growth forests to young forests.
Harmon ME, Ferrell WK, Franklin JF.
Science. 1990 Feb 9;247(4943):699-702.
Simulations of carbon storage suggest that conversion of old-growth forests to young fast-growing forests will not decrease atmospheric carbon dioxide (CO(2)) in general, as has been suggested recently. During simulated timber harvest, on-site carbon storage is reduced considerably and does not approach old-growth storage capacity for at least 200 years. Even when sequestration of carbon in wooden buildings is included in the models, timber harvest results in a net flux of CO(2) to the atmosphere. To offset this effect, the production of lumber and other long-term wood products, as well as the life-span of buildings, would have to increase markedly. Mass balance calculations indicate that the conversion of 5 x 10(9) to 1.8 x 10(9) megagrams of carbon to the atmosphere.
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Old-growth forests as global carbon sinks
Nature 455, 213-215 (11 September 2008) | doi:10.1038/nature07276; Received 18 January 2008; Accepted 7 July 2008
Sebastiaan Luyssaert1,2, E. -Detlef Schulze3, Annett Börner3, Alexander Knohl4, Dominik Hessenmöller3, Beverly E. Law2, Philippe Ciais5 & John Grace6
Old-growth forests remove carbon dioxide from the atmosphere1, 2 at rates that vary with climate and nitrogen deposition3. The sequestered carbon dioxide is stored in live woody tissues and slowly decomposing organic matter in litter and soil4. Old-growth forests therefore serve as a global carbon dioxide sink, but they are not protected by international treaties, because it is generally thought that ageing forests cease to accumulate carbon5, 6. Here we report a search of literature and databases for forest carbon-flux estimates. We find that in forests between 15 and 800 years of age, net ecosystem productivity (the net carbon balance of the forest including soils) is usually positive. Our results demonstrate that old-growth forests can continue to accumulate carbon, contrary to the long-standing view that they are carbon neutral. Over 30 per cent of the global forest area is unmanaged primary forest, and this area contains the remaining old-growth forests7. Half of the primary forests (6?×?108 hectares) are located in the boreal and temperate regions of the Northern Hemisphere. On the basis of our analysis, these forests alone sequester about 1.3?±?0.5 gigatonnes of carbon per year. Thus, our findings suggest that 15 per cent of the global forest area, which is currently not considered when offsetting increasing atmospheric carbon dioxide concentrations, provides at least 10 per cent of the global net ecosystem productivity8. Old-growth forests accumulate carbon for centuries and contain large quantities of it. We expect, however, that much of this carbon, even soil carbon9, will move back to the atmosphere if these forests are disturbed.
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Dumbass western conservatives have tried to convince folks that clear-cutting old growth forests is "good for the environment" - but its nothing more than ignorant greenwash/bullshit
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