Abstract

There is a traditional view suggesting forests remove carbon dioxide from the atmosphere (Pregitzer & Euskirchen, 2004), but they cease to serve as a carbon sink as they fully mature (Odum, 1969).  Recent modeling of old-growth forests indicate they continue to serve as a “net sink” of carbon even after maturity (Carey, Sala, & Callaway, 2001; Zhou, 2006), sequestering an average of 2.4 +/- 0.8 tC ha^-1 yr^-1 (tC = metric tons of carbon; ha = hectare; yr =year), identifying a ratio of heterotrophic respiration (Rh) to net primary production (NPP) of approximately 0.65 +/- 0.02 (Luyssaert, 2008).  These figures show the strongest correlation amongst temperate forest regions.  Two calculations are made using the carbon sequestration average.  One is made identifying the amount of carbon sequestered through a small-scale land protection organization, showing a net carbon sequestration of approximately 224 metric tons of carbon per year.  The other is based on the amount of land required to offset current anthropogenic emissions of carbon in the global carbon budget, showing approximately 235 million hectares of new forest growth would be required to offset current global anthropogenic emissions.  One implication of these calculations is the traditional assumption of carbon neutrality increasing with age (Magnani, 2007) is incorrect, suggesting re-growing forests may be a favored policy choice for continued carbon sequestration.

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