Old Growth Forests - Climatic Impacts

Climatic Impacts

The effects of old-growth forests in relation to Global Warming has been contested in various studies and journals.

While some studies that old-growth forests are an important part of carbon sequestration and its impacts on climate change and climate change mitigation. The Intergovernmental Panel on Climate Change said in its 2007 report: “In the long term, a sustainable forest management strategy aimed at maintaining or increasing forest carbon stocks, while producing an annual sustained yield of timber, fibre or energy from the forest, will generate the largest sustained mitigation benefit.”

Critics note that at old-growth forests are often perceived to be in equilibrium, but could be releasing as much carbon dioxide as they capture, or are currently in a state of decay. Another scientific studie concluded that forest harvesting has little or no effect on the amount of carbon stored in the soil. As trees grow, they remove carbon from the atmosphere. As they reach maturity, growth slows and ultimately stops as mortality catches up to growth. Harvesting also removes carbon from the forest but some of it is stored in wood products (preventing its immediate release to the atmosphere) and some is available for use as biomass energy (displacing fossil fuel use), although using biomass as a fuel produces air pollution in the form of carbon monoxide, NOx (nitrogen oxides), VOCs (volatile organic compounds), particulates and other pollutants, in some cases at levels above those from traditional fuel sources such as coal or natural gas. In most North American forests, this drop happens when a tree is between 60 and 150 years old, depending on the species and environmental factors.

Each forest has a different potential to store carbon. For example, this potential is particularly high in the Pacific Northwest where forests are relatively productive, trees live a long time, decomposition is relatively slow, and fires are infrequent. The differences between forests must therefore be taken into consideration when determining how they should be managed to store carbon.