Interactive effects of environmental change and management strategies on regional forest carbon emissions.

Climate mitigation activities in forests need to be quantified in terms of the long-term effects on forest carbon stocks, accumulation, and emissions. The impacts of future environmental change and bioenergy harvests on regional forest carbon storage have not been quantified. We conducted a comprehensive modeling study and life-cycle assessment of the impacts of projected changes in climate, CO2 concentration, and N deposition, and region-wide forest management policies on regional forest carbon fluxes. By 2100, if current management strategies continue, then the warming and CO2 fertilization effect in the given projections result in a 32-68% increase in net carbon uptake, overshadowing increased carbon emissions from projected increases in fire activity and other forest disturbance factors. To test the response to new harvesting strategies, repeated thinnings were applied in areas susceptible to fire to reduce mortality, and two clear-cut rotations were applied in productive forests to provide biomass for wood products and bioenergy. The management strategies examined here lead to long-term increased carbon emissions over current harvesting practices, although semiarid regions contribute little to the increase. The harvest rates were unsustainable. This comprehensive approach could serve as a foundation for regional place-based assessments of management effects on future carbon sequestration by forests in other locations.

[1]  T. Beringer,et al.  The global technical potential of bio-energy in 2050 considering sustainability constraints , 2010, Current opinion in environmental sustainability.

[2]  R. Harrod,et al.  Thinning and prescribed fire effects on overstory tree and snag structure in dry coniferous forests of the interior Pacific Northwest , 2009 .

[3]  A. Taylor,et al.  Widespread Increase of Tree Mortality Rates in the Western United States , 2009, Science.

[4]  M. Harmon,et al.  Modeling carbon stores in Oregon and Washington forest products: 1900–1992 , 1996 .

[5]  Christian Körner,et al.  Slow in, Rapid out--Carbon Flux Studies and Kyoto Targets , 2003, Science.

[6]  B. Quayle,et al.  A Project for Monitoring Trends in Burn Severity , 2007 .

[7]  David P. Turner,et al.  Atmospheric inverse modeling to constrain regional-scale CO2 budgets at high spatial and temporal resolution , 2010 .

[8]  Helmut Haberl,et al.  Large‐scale bioenergy from additional harvest of forest biomass is neither sustainable nor greenhouse gas neutral , 2012 .

[9]  J. Randerson,et al.  Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997-2009) , 2010 .

[10]  Arpad Horvath,et al.  Greenhouse Gas Emissions from the Construction, Manufacturing, Operation, and Maintenance of U.S. Distribution Infrastructure for Petroleum and Biofuels , 2013 .

[11]  Sunil Kumar,et al.  Assessing Forest Vulnerability and the Potential Distribution of Pine Beetles Under Current and Future Climate Scenarios in the Interior West of the US , 2011 .

[12]  B. Law,et al.  Evaluation and improvement of the Community Land Model ( CLM 4 . 0 ) in Oregon forests , 2012 .

[13]  Peter E. Thornton,et al.  Simulating the Biogeochemical and Biogeophysical Impacts of Transient Land Cover Change and Wood Harvest in the Community Climate System Model (CCSM4) from 1850 to 2100 , 2012 .

[14]  R. S. Kennedy,et al.  Decadal trends in net ecosystem production and net ecosystem carbon balance for a regional socioecological system , 2011 .

[15]  Daniel C. Donato,et al.  Forest Fire Impacts on Carbon Uptake, Storage, and Emission: The Role of Burn Severity in the Eastern Cascades, Oregon , 2009, Ecosystems.

[16]  B. Law.  Biogeochemistry: Nitrogen deposition and forest carbon , 2013, Nature.

[17]  M. Harmon,et al.  Carbon debt and carbon sequestration parity in forest bioenergy production , 2012 .

[18]  B. Hungate,et al.  Aligning ecology and markets in the forest carbon cycle , 2013 .

[19]  W. Kurz,et al.  Could increased boreal forest ecosystem productivity offset carbon losses from increased disturbances? , 2008, Philosophical Transactions of the Royal Society B: Biological Sciences.

[20]  C. Wirth,et al.  Reconciling Carbon-cycle Concepts, Terminology, and Methods , 2006, Ecosystems.

[21]  Biomass Sustainability and Carbon Policy Study , 2022 .

[22]  Peter E. Thornton,et al.  Generating surfaces of daily meteorological variables over large regions of complex terrain , 1997 .

[23]  L. Gustavsson,et al.  Life cycle impacts of forest management and wood utilization on carbon mitigation: knowns and unknowns , 2011 .

[24]  Jason J. Moghaddas,et al.  Fuel treatment effects on stand-level carbon pools, treatment-related emissions, and fire risk in a Sierra Nevada mixed-conifer forest. , 2009 .

[25]  B. Law,et al.  Pyrogenic carbon emission from a large wildfire in Oregon, United States , 2007 .

[26]  C. Gough,et al.  The legacy of harvest and fire on ecosystem carbon storage in a north temperate forest , 2007 .

[27]  Christian Wirth,et al.  Regional carbon dioxide implications of forest bioenergy production , 2011 .

[28]  Richard York.  Asymmetric effects of economic growth and decline on CO 2 emissions , 2012 .

[29]  J. Bowyer,et al.  Managing Forests because Carbon Matters: Integrating Energy, Products, and Land Management Policy , 2011, Journal of Forestry.

[30]  Thinning effects on forest productivity: consequences of preserving old forests and mitigating impacts of fire and drought , 2013 .

[31]  W. Parton,et al.  Harvesting Carbon from Eastern US Forests: Opportunities and Impacts of an Expanding Bioenergy Industry , 2012 .

[32]  Leif Gustavsson,et al.  Primary energy and greenhouse gas implications of increasing biomass production through forest fertilization , 2010 .

[33]  Bjart Holtsmark.  Material for : Harvesting in boreal forests and the biofuel carbon debt , 2011 .

[34]  Mark E. Harmon,et al.  Forest sector carbon management, measurement and verification, and discussion of policy related to climate change , 2011 .

[35]  D. Lawrence,et al.  Parameterization improvements and functional and structural advances in Version 4 of the Community Land Model , 2011 .

[36]  W. Post,et al.  North American carbon dioxide sources and sinks: magnitude, attribution, and uncertainty , 2012 .

[37]  Johanna Routa,et al.  Effects of forest management on the carbon dioxide emissions of wood energy in integrated production of timber and energy biomass , 2011 .

[38]  B. Law,et al.  Evaluation and improvement of the Community Land Model (CLM4) in Oregon forests , 2012 .

[39]  R. B. Jackson,et al.  A Large and Persistent Carbon Sink in the World’s Forests , 2011, Science.

[40]  Jeffrey G. Masek,et al.  Carbon consequences of forest disturbance and recovery across the conterminous United States , 2012 .

[41]  Jason J. Moghaddas,et al.  Fire treatment effects on vegetation structure, fuels, and potential fire severity in western U.S. forests. , 2009, Ecological applications : a publication of the Ecological Society of America.

[42]  J. Hicke,et al.  Cross-scale Drivers of Natural Disturbances Prone to Anthropogenic Amplification: The Dynamics of Bark Beetle Eruptions , 2008 .

[43]  B. Duval,et al.  Altered dynamics of forest recovery under a changing climate , 2013, Global change biology.

[44]  S. Malyshev,et al.  The underpinnings of land‐use history: three centuries of global gridded land‐use transitions, wood‐harvest activity, and resulting secondary lands , 2006 .

[45]  W. Keeton,et al.  Factors contributing to carbon fluxes from bioenergy harvests in the U.S. Northeast: an analysis using field data , 2013 .

[46]  Mark E Harmon,et al.  Forest fuel reduction alters fire severity and long-term carbon storage in three Pacific Northwest ecosystems. , 2009, Ecological applications : a publication of the Ecological Society of America.

[47]  Alan A Ager,et al.  Forest wildfire, fuel reduction treatments, and landscape carbon stocks: a sensitivity analysis. , 2013, Journal of environmental management.

[48]  H. MacLean,et al.  Forest bioenergy or forest carbon? Assessing trade-offs in greenhouse gas mitigation with wood-based fuels. , 2011, Environmental science & technology.

[49]  H. Tian,et al.  Century-Scale Responses of Ecosystem Carbon Storage and Flux to Multiple Environmental Changes in the Southern United States , 2012, Ecosystems.

[50]  Bjart Holtsmark,et al.  The outcome is in the assumptions: analyzing the effects on atmospheric CO2 levels of increased use of bioenergy from forest biomass , 2013 .

[51]  R. Neilson,et al.  Impacts of climate change on fire regimes and carbon stocks of the U.S. Pacific Northwest , 2011 .

[52]  Malcolm P. North,et al.  Carbon recovery rates following different wildfire risk mitigation treatments , 2010 .

[53]  R. Barbour,et al.  Woody biomass supply from thinnings to reduce fire hazard in the U.S. West and its potential impact on regional wood markets , 2008 .

[54]  T. Swetnam,et al.  Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity , 2006, Science.

[55]  Maureen E. Puettmann,et al.  Sustainable Biofuel Contributions to Carbon Mitigation and Energy Independence , 2011 .

[56]  Warren B. Cohen,et al.  Scaling net ecosystem production and net biome production over a heterogeneous region in the Western United States , 2007 .

[57]  B. Law,et al.  Carbon dynamics of a ponderosa pine plantation following a thinning treatment in the northern Sierra Nevada , 2009 .