Old Growth Forests Are Carbon Sinks and Must Be Protected

A forest levy and other financial mechanisms within the Kyoto Protocol are appropriate measures for protecting natural forests. Dr. Mae-Wan Ho General misconception leaves old growth forests especially vulnerable to wonton destruction Old-growth forests sequester carbon in live woody tissues and in slowly decomposing litter on the ground and buried in the soil, thereby acting as effective global carbon sinks.

Yet, they are not protected by international treaties because of general misconception that ageing forests cease to accumulate carbon. An international team of scientists led by Sebastian Luyssaert at the University of Antwerp in Belgium reviewed the literature and existing databases for forests between 15 and 800 years old. They found that all forests, from the youngest to the oldest, show positive net ecosystem productivity; i.e., they are growing and hence sequestering or accumulating carbon [1].

Over 30 percent of the global forest area is unmanaged primary forest and this area contains the remaining old growth forests. Half of the primary forests (covering 600 million ha) are located in boreal (near the Arctic) and temperate regions in the Northern Hemisphere. These forests alone sequester about 1.3 + 0.5 Gt of C per year. This 15 percent of the global forest area currently not considered when offsetting increasing atmospheric CO2, provides at least 10 percent of the global net ecosystem productivity.

Old-growth forests accumulate carbon for centuries and contain large quantities that will move back into the atmosphere if these forests are disturbed or cut down, especially tropical forests [2, 3] (Saving and Restoring Forests Saves Far More Carbon Emissions than Biofuels, SiS 37) .

Net ecosystem productivity and age of forests Net ecosystem productivity (NEP) is the net carbon balance of the forest ecosystem as a whole, and is the difference between CO2 uptake by photosynthetic assimilation and losses through plant and soil respiration. Tropical forests were excluded from the study because of the lack of data, and only 12 sites were found for which NEP and age estimates are available.

Copyright Issues?