The boreal region of Alaska has vast forests spanning hundreds of thousands of square kilometers in the central portion of the state that is prone to large stand replacing summer wildfires. The region stores considerable quantities of terrestrial carbon sequestered in soil horizons down to 1 meter in depth that are strongly influenced by a combination of climate change, permafrost dynamics, vegetative composition, and fire regimes. Data and literature establish that the boreal region of Alaska (and the rest of the Arctic) has been steadily warming at a rate nearly double that of lower latitudes. This warming has resulted in larger fires defined by shorter return intervals. This altered fire regime places the vast stocks of organic soil carbon at risk to greater degrees of combustion, potentially contributing millions more tons of CO2 to the atmosphere in the Arctic region. Between 2000-2015 roughly 5% (~28,000 km2) of the over 560,000 km2 of the boreal region burned, raising CO2 levels and supporting a positive feedback loop between climate and fires; when considering that this region of Alaska is larger than the state of California (~420,000 km2) these emissions are significant. Mean summer temperatures have risen by 1.4° C over the last 100 years, resulting in shorter fire return intervals characterized by more severe and intense, longer fire seasons. This warming is driving more pronounced permafrost degradation that is altering both the extent and depth of regional permafrost layers, increasing labile carbon stocks that serve as additional fuel pools for fires. While permafrost layers are fluctuating more frequently, the warmer temperatures are supporting increased vegetation growth with expansion of the boreal forest into landscapes that were previously hostile, increasing novelty in these area's fire regimes and subsequent emissions. As fire activity increases in the region, forest composition is being altered toward a greater dominance by deciduous rather than coniferous trees, a development that is increasing soil carbon levels as these stands mature. Human suppression policies, despite being well intentioned, are driving more frequent and severe fires due to an unnatural buildup of fuels, especially around regional population centers. Because of these findings, I recommend closing critical data gaps with further data additions, changing timber harvesting and forest management policies, and reexamining fire suppression policies.

"Boreal forests contain large amounts of soil carbon and are susceptible to periodic wildfires. Predicting the response of soil carbon dynamics to fire disturbance requires understanding: (1) the environmental factors governing CO2 efflux; (2) the extent to which fire alters these factors; and, (3) the length of time over which these perturbations persist. In interior Alaska seasonal patterns of CO2 efflux, soil temperature. and soil moisture potential were measured in burned and control pairs of aspen, white spruce, and black spruce stands. Averaged over the growing season, mean CO2 efflux from burned stands (0.51 ± 0.26 g CO2 m−2 hr−1) was two-thirds that of control stands (0.77 ± 0.44 g CO2 M−2 hr1). Soil temperature explained 85 to 90% of the seasonal variability in the control, whereas moisture was a more important determinant in burned stands. Laboratory incubations of recently burned and control humic material indicate that changes in substrate chemistry and increased temperature may enhance rates of decomposition by a factor of 2.2 to 2.8 in the first decade after fire, resulting in a release of 6.3 to 13.4 Mg C ha−1 to the atmosphere. Under saturated moisture conditions, respiration from mosses may contribute 16 to 50% of total soil CO2 emissions. In a 140-year age-sequence of burned black spruce stands, CO2 efflux increased at an average rate of 8.3 kg C ha−1 yr1 up to a maximum of 1.83 Mg C ha−1 yr1. During this same time, accumulation of carbon in organic horizons ranges from 0.34 to 0.50 Mg C ha−1 yr1 and the ratio of microbial to root respiration decreased from 76:24 to 13:87. Numerical modeling of carbon accumulation suggests that these soils functioned as a net source of carbon for the first 7 to 15 years after fire and released 1.8 to 11.0 Mg C ha−1 to the atmosphere. Although conservative, these estimates of post-fire biogenic emissions are on the same order of magnitude as carbon losses during combustion itself, suggesting that current models may underestimate the impact of fire in northern latitudes by as much as a factor of two"--Leaves iv-v.

A discussion of the direct and indirect mechanisms by which fire and climate interact to influence carbon cycling in North American boreal forests. The first section summarizes the information needed to understand and manage fires' effects on the ecology of boreal forests and its influence on global climate change issues. Following chapters discuss in detail the role of fire in the ecology of boreal forests, present data sets on fire and the distribution of carbon, and treat the use of satellite imagery in monitoring these regions as well as approaches to modeling the relevant processes.

Much attention has been given to above ground biomass and its potential as a carbon sink, but in a mature forest ecosystem 40 to 60 percent of the stored carbon is below ground. As increasing numbers of forests are managed in a wide diversity of climates and soils, the importance of forest soils as a potential carbon sink grows. The Potenti

Interactions between forests, climatic change and the Earths carbon cycle are complex and represent a challenge for forest managers they are integral to the sustainable management of forests. In this volume, a number of papers are presented that describe some of the complex relationships between climate, the global carbon cycle and forests. Research has demonstrated that these are closely connected, such that changes in one have an influence not only on the other two, but also on their linkages. Climatic change represents a considerable threat to forest management in the current static paradigm. However, carbon sequestration issues offer opportunities for new techniques and strategies, and those able to adapt their management to this changing situation are likely to benefit. Such changes are already underway in countries such as Australia and Costa Rica, but it will probably take much longer for the forestry sector in the Pacific Northwest region of North America (encompassing Oregon, Washington, Montana, Idaho, British Columbia and Alaska) to change their current practices.

Abstract: "This report documents trends and impacts of climate change on America's forests as required by the Renewable Resources Planning Act of 1974. Recent research on the impact of climate and elevated atmospheric carbon dioxide on plant productivity is synthesized. Modeling analyses explore the potential impact of climate changes on forests, wood products, and carbon in the United States."

There are opportunities for forest owners and ranchers to participate in emerging carbon markets and contribute to climate change mitigation through carbon-oriented forest and range mgmt. activities. These activities often promote sustainable forestry and ranching and broader conservation goals while providing a new income stream for landowners. The authors describe current carbon market opportunities for landowners, discuss common steps they must undergo to take advantage of these opportunities, and address related questions. Also provides a synthesis of the existing scientific literature on how different forest and range mgmt. practices are thought to contribute to carbon sequestration, including current debates on this topic.