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Background on Strategy G
Enhance carbon storage in Oregon's forests and forest products

What is global climate change?
Carbon dioxide is one of the gases found naturally in the earth's atmosphere. It is widely accepted and well documented that atmospheric levels of carbon dioxide have increased dramatically over the past 100 years. The increased level of carbon dioxide in the atmosphere acts much like a greenhouse, allowing sunlight in and trapping its heat so as to keep the air warm. Other gases in the atmosphere, such as methane and nitrous oxide, have the same effect. These gases are referred to collectively as greenhouse gases.
Studies have shown a strong relationship over the past 100 million years between the levels of atmospheric greenhouse gases and the earth's temperature. Many scientists believe the greenhouse effect from increased levels of atmospheric carbon dioxide is increasing the earth's average temperature to the point of undesirably changing the earth's climate-a phenomenon referred to as "global warming" or "global climate change."
 
Many scientists, policy-makers, and others believe that climate change from increasing atmospheric levels of greenhouse gases needs to be addressed by reducing or offsetting human-induced sources of greenhouse gases, in particular carbon dioxide. Proponents for taking action feel that doing nothing is too risky, and that inaction forecloses opportunities to achieve other benefits such as conserving energy, developing alternatives to fossil fuels, and placing greater emphasis on maintaining healthy, productive forests to mitigate carbon dioxide emissions. Others question whether climate change from increased levels of carbon dioxide is occurring, and if it is, whether humans are causing the changes and whether society needs to be concerned.
 
How does carbon move from the atmosphere to plants and back again?
All plants use energy from the sun's light to make their own food in a process called photosynthesis. During photosynthesis, carbon dioxide absorbed through leaves is broken down by the sun's energy and combined with hydrogen from water to make sugars that plants live on. This process releases oxygen into the air. The carbon in the sugars is stored as biomass in the plant's leaves, branches, trunk, and roots.
 
Plants break down the sugars into energy. This process, called respiration, releases carbon dioxide back into the air. Plants use much more carbon dioxide in making their food and storing it as biomass than they release during respiration. The remainder of the carbon is stored in their tissues. The process of removing carbon dioxide from the atmosphere, breaking it down into carbon, and storing the carbon in living and dead plant tissues and as organic material in the soil is called carbon sequestration. The carbon returns to the atmosphere as carbon dioxide when plants die, decompose, or burn. When trees are harvested and manufactured, carbon continues to be stored in lumber and other wood products until they decompose. Collectively, these processes are called the carbon cycle.
People, in their use of the earth's resources, are very much a part of the carbon cycle (Figure 17). For example, when we burn fossil fuels such as coal and natural gas to produce electricity or run our automobiles on gasoline, carbon dioxide is emitted as waste into the atmosphere. Similarly, clearing forestland for other uses not only reduces the area where carbon sequestration and storage can occur, but the clearing itself (i.e., removing stumps and disposing of slash) also releases stored carbon back into the atmosphere as carbon dioxide.

How do forests and forest management affect the carbon cycle?
The role of forests in the global carbon cycle and the use of forests to offset increases in atmospheric carbon dioxide have been widely discussed. It is very important to keep scale in mind when discussing the effects of forests and forest management on carbon storage.
The carbon cycle occurs at various scales-individual trees and plants, forest stands, and landscapes containing many forest stands. The plants themselves are a pool of stored carbon. At the stand scale, the age, species composition, and forest structure define the types of carbon pools present. Young conifer forests are very productive and grow rapidly. The pool of stored carbon in young forests is modest in size, but it increases rapidly, and it is made up mostly of the living trees themselves. An older forest containing trees of different ages, sizes, and species is still sequestering and storing carbon. The rate at which carbon is being stored (amount per unit of biomass) is lower than in a young forest, but there is more biomass present in an older forest. In addition to live-tree biomass, older forests contain other carbon pools: dead trees, leaf litter, duff, and organic material in the soil. The distribution of forest stands with respect to age, species composition, size, and structure is what determines the amount of carbon stored at landscape scales.

The size, frequency, and severity of natural disturbances such as floods, wildfire, wind, and insect and disease infestations greatly influence the carbon cycle at all scales. Losses of large expanses of forests to wildfires, insects, or diseases release carbon dioxide back into the atmosphere, either directly through combustion, or indirectly through increased decomposition. However, apparently catastrophic events do not necessarily have a net negative effect on stored carbon. The severity of forest losses can vary over the affected area, and stored carbon may be transferred from the living biomass pool to standing dead and down trees, rather than being released back into the atmosphere. Rapid regrowth of vegetation further offsets carbon losses from natural disturbances as the growing plants sequester carbon dioxide from the air.
 
Forest management influences the carbon cycle. Site preparation and timber harvest create logging slash and disturb down wood, leaf litter, duff, and other organic material in the soil. This results in increased decomposition, which releases stored carbon into the atmosphere as carbon dioxide. However, these effects are temporary if the subsequent forest is well stocked and managed to ensure its long-term health and productivity. Also, the utilization of harvested timber for wood products transfers stored carbon from the forest to homes, buildings, and furniture and continues the carbon storage benefits beyond the timber harvest rotation.
 
Carbon releases from natural disturbances can be minimized by reducing the risk of loss through management actions that maintain the forest's health and productivity, such as reduction of hazardous fuels, timber harvest, thinning, and prescribed fire, or combinations of these measures. While these actions may lead to reduced levels of stored carbon on the acres treated at the stand level, they maintain and enhance the overall carbon storage of the forested landscape by reducing the risk of wildfire and pests and by reducing the size and severity of loss when fire or pest outbreaks occur.
 
There is tremendous opportunity to increase the carbon storage ability of Oregon's forests. Planting trees along city streets and neighborhoods, converting marginal agricultural and pasture land back into forests, extending forest rotations, reducing stand density and wildfire fuels, and increasing the size and complexity of forest structures, all would increase carbon storage in forests. Encouraging people to use wood products instead of cement and steel (which emit more carbon dioxide during their manufacture) and discouraging the conversion of forestland to non-forest uses are perhaps the most important actions Oregon can take to increase carbon storage. In summary, we can make big gains in carbon storage by simply increasing the amount of land in forest and using renewable and recyclable wood materials.
 
What kinds of policies encourage forest landowners to maintain and increase the contribution of their forestlands to global carbon storage?
Oregon has a strong history of promoting policies that encourage the productive management of forestlands for the full array of environmental, economic, and social values people want from forests. While these policies have not explicitly recognized the benefits forests provide to carbon storage, they nonetheless have maintained the positive role Oregon's forests play in the carbon cycle by encouraging the management of forestland.
 
Through the Forest Practices Act, the State of Oregon encourages economically efficient forest practices that ensure the continuous growing and harvesting of forests consistent with the protection of soil, air, water, fish and wildlife, and scenic resources. The law specifically ensures the renewability of the forest by requiring that all areas harvested for commercial timber be promptly reforested to new "free-to-grow" stands. While the benefits of carbon sequestration were not explicitly recognized at the time of the law's development, this reforestation requirement ensures that Oregon's state, private, county, and municipal forests contribute positively to the carbon cycle. Oregon is also a leader in protecting productive forestland from being converted to non-forest uses such as urban and rural residential development. Over the period 1973-2000, only two percent of Oregon's non-federal wildland forest and seven percent of western Oregon's non-federal mixed agricultural-forest acreage was lost to development (see Strategy C).
 
In the early 1990s Oregon's two major power suppliers, PacifiCorp and Portland General Electric, both began using trees and forests as a means to offset carbon dioxide emissions. By the mid-1990s, Oregon's policy link between carbon dioxide emissions and forests was established by the Oregon Energy Facility Siting Council's "best of batch" site license competition. The competition was intended to encourage power providers to find creative ways to reduce carbon dioxide emissions. The Klamath Cogeneration Project won the competition by demonstrating the lowest net carbon dioxide emission level through efficiency, co-generation, and specific offset projects, including the investment of $1.5 million into Oregon's Forest Resource Trust. The Forest Resource Trust is a state incentive program that finances efforts to convert marginal agricultural, pasture, and brush land on nonindustrial private forestlands to healthy, productive forest. The Klamath project investment in the trust is expected to offset 1.16 million metric tons of atmospheric carbon dioxide by restoring forests on 2,400 acres over a 100-year period.
 
Based on these efforts, Oregon became a recognized leader in developing energy policies directed at reducing human-induced carbon dioxide emissions from the burning of fossil fuels. In 1997, the Oregon Legislature adopted a carbon dioxide emission standard for new power-generating facilities. Besides promoting efficiency, energy conservation, and cogeneration, the law allowed new power plants to fund specific offset projects including those involving forests. The Climate Trust, a nongovernmental organization, was set up to disseminate funds for eligible offset projects under the law's monetary path provision. In effect, power companies pay in advance for their carbon dioxide emissions by funding The Climate Trust-leaving the Climate Trust with the task of finding projects that will offset their carbon dioxide emissions. The Climate Trust has awarded several offset project grants, including two involving forests.
 
In 2001, the Oregon Legislature passed a law that established forestry carbon offsets as a marketable commodity. The law authorizes the state forester to sell carbon offsets on behalf of landowners to energy companies, power plants, or other businesses wishing to mitigate the effects of their carbon dioxide emissions. The innovative law18 anticipates that forest landowners who invest in forest management to improve the carbon-storage capability of their forestlands can get a return on this investment.
 
What are the key interactions of this strategy with other strategies?
Enhancing carbon storage in Oregon's forests affects, and is affected by, other strategies and policies for managing Oregon's forests. Here are some examples of these interactions:
  • The productive capacity of forests defines how much carbon dioxide can be removed from the atmosphere through sequestration and storage. Conversion of forestland to other uses directly reduces carbon storage in Oregon's forests.
  • Forests in poor health and in decline can be net sources of carbon dioxide released back into the atmosphere.
  • Managing fuel and stocking levels stabilizes and maintains carbon stores in forested landscapes by helping to ensure that wildfires do not destroy those essential components that define the forest ecosystem.
  • Soils are important carbon pools, and many practices that prevent erosion and protect and conserve forest soils serve to maintain and enhance the carbon pools found in leaf litter, duff, humus, and other organic material.
What are potential indicators to measure progress toward accomplishing this strategy?
1. Amount of stored carbon in forests and forest products
 
2. Number of verifiable projects to offset carbon dioxide emissions by restoring or enhancing forests.