Fuel treatment effects on modeled landscape- level fire behavior in the northern Sierra Nevada

Across the western United States, decades of fire exclusion combined with past management history have con- tributed to the current condition of extensive areas of high-density, shade-tolerant coniferous stands that are increasingly prone to high-severity fires. Here, we report the modeled effects of constructed defensible fuel profile zones and group se- lection treatments on crown fire potential, flame length, and conditional burn probabilities across 11 land allocation types for an 18 600 ha study area within the northern Sierra Nevada, California. Fire modeling was completed using FlamMap and FARSITE based on landscape files developed with high-resolution aerial (IKONOS) imagery, ground-based plot data, and integrated data from ARCFUELS and the Forest Vegetation Simulator. Under modeled 97th percentile weather condi- tions, average conditional burn probability was reduced between pre- and post-treatment landscapes. A more detailed simu- lation of a hypothetical fire burning under fairly severe fire weather, or ''problem fire'', revealed a 39% reduction in final fire size for the treated landscape relative to the pre-treatment condition. To modify fire behavior at a landscape level, a combination of fuel treatment strategies that address topographic location, land use allocations, vegetation types, and fire regimes is needed. Resume´ : Partout dans l'ouest des Etats-Unis, des decennies d'exclusion du feu combinee aux pratiques d'amenagement passees ont contribuea la situation actuelle caracterisee par de vastes superficies de peuplements de coniferes tolerants a l'ombre qui sont de plus en plus sujets ades feux de severiteelevee. Ici, nous rapportons les effets de la construction de coupe-feu ombrages et de traitements de jardinage par groupe sur le potentiel de feu de cime, la longueur de flamme et les probabilites de brulage conditionnel parmi 11 types d'affectation des terres dans une aire d'etude de 18 600 ha situee dans la partie septentrionale de la Sierra Nevada, en Californie. La modelisation du feu a eterealiseeal'aide de FlamMap et de FARSITE sur la base de fichiers de paysage elaboresapartir de l'imagerie aerienne (IKONOS) a haute resolution, de donnees terrain provenant de placettes echantillons et de donnees integrees provenant de ARCFUELS et du Simulateur de vegetation forestiere. Sur la base de conditions meteorologiques modelisees au 97 e percentile, la probabilitemoyenne de brulage conditionnel etait reduite en comparant les paysages pre ´- et post-traitement. Une simulation plus detaillee d'un feu hypothetique brulant dans des conditions meteorologiques assez severes, ou un feu problematique, a reveleque la di- mension finale du feu etait reduite de 39 % dans le cas du paysage traiterelativement a la situation anterieure au traite- ment. Pour modifier le comportement du feu al'echelle du paysage, il faut avoir recours a une combinaison de strategies de traitement des combustibles qui tiennent compte de la situation topographique, de l'affectation des terres, du type de vegetation et du regime des feux. (Traduit par la Redaction)

[1]  Nicholas L. Crookston,et al.  Incorporating landscape fuel treatment modeling into the Forest Vegetation Simulator , 2008 .

[2]  M. Barbour,et al.  Terrestrial Vegetation of California, New Expanded Edition. , 1990 .

[3]  Nicole M. Vaillant,et al.  Integrating Fire Behavior Models and Geospatial Analysis for Wildland Fire Risk Assessment and Fuel Management Planning , 2011 .

[4]  J. Agee.  The Fallacy of Passive Management Managing for Firesafe Forest Reserves , 2002 .

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

[6]  P. Fulé,et al.  Pre-wildfire fuel treatments affect long-term ponderosa pine forest dynamics , 2007 .

[7]  李幼升,et al.  Ph , 1989 .

[8]  T. Spies,et al.  Conserving Old‐Growth Forest Diversity in Disturbance‐Prone Landscapes , 2006, Conservation biology : the journal of the Society for Conservation Biology.

[9]  S. Stephens.  Mixed conifer and red fir forest structure and uses in 1899 from the central and northern Sierra Nevada, California. , 2000 .

[10]  Bret W. Butler,et al.  High Resolution Wind Direction and Speed Information for Support of Fire Operations , 2006 .

[11]  M. Finney.  FARSITE : Fire Area Simulator : model development and evaluation , 1998 .

[12]  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.

[13]  C. Skinner,et al.  Probability of tree survival after wildfire in an interior pine forest of northern California: Effects of thinning and prescribed fire , 2007 .

[14]  Jay D. Miller,et al.  Quantitative Evidence for Increasing Forest Fire Severity in the Sierra Nevada and Southern Cascade Mountains, California and Nevada, USA , 2009, Ecosystems.

[15]  Jason J. Moghaddas,et al.  A fuel treatment reduces fire severity and increases suppression efficiency in a mixed conifer forest , 2007 .

[16]  Kevin E. Shaffer.  Prescribed Burning in California Wildlands Vegetation Management , 2001 .

[17]  Philip N. Omi,et al.  The use of shaded fuelbreaks in landscape fire management. , 2000 .

[18]  Scott L. Stephens,et al.  Operational approaches to managing forests of the future in Mediterranean regions within a context of changing climates , 2010 .

[19]  H. Safford,et al.  Effects of fuel treatments on fire severity in an area of wildland-urban interface, Angora Fire, Lake Tahoe Basin, California , 2009 .

[20]  Carl N. Skinner,et al.  Basic principles of forest fuel reduction treatments , 2005 .

[21]  M. Finney.  Design of Regular Landscape Fuel Treatment Patterns for Modifying Fire Growth and Behavior , 2001, Forest Science.

[22]  L. Kobziar,et al.  The efficacy of fire and fuels reduction treatments in a Sierra Nevada pine plantation , 2009 .

[23]  Charles W. McHugh,et al.  Stand- and landscape-level effects of prescribed burning on two Arizona wildfires , 2005 .

[24]  S. Stephens,et al.  FEDERAL FOREST‐FIRE POLICY IN THE UNITED STATES , 2005 .

[25]  Jason J. Moghaddas,et al.  Silvicultural and reserve impacts on potential fire behavior and forest conservation: Twenty-five years of experience from Sierra Nevada mixed conifer forests , 2005 .

[26]  Charles W. McHugh,et al.  Simulation of long-term landscape-level fuel treatment effects on large wildfires , 2006 .

[27]  Klaus H. Barber,et al.  Stewardship and fireshed assessment: a process for designing a landscape fuel treatment strategy. , 2007 .

[28]  E. Cranbrook.  A conspiracy of Optimism: Management of the National Forests since World War Two , 2004, Biodiversity & Conservation.

[29]  S. Stehman,et al.  Public perceptions of the USDA Forest Service public participation process , 2001 .

[30]  E. Pastor,et al.  Mathematical models and calculation systems for the study of wildland fire behaviour , 2003 .

[31]  Jennifer M. Menzel,et al.  Effects of group selection silviculture in bottomland hardwoods on the spatial activity patterns of bats , 2002 .

[32]  J. Battles,et al.  Group selection management in conifer forests: relationships between opening size and tree growth , 2004 .

[33]  Charles W. McHugh,et al.  A simulation study of thinning and fuel treatments on a wildland–urban interface in eastern Oregon, USA , 2007 .

[34]  Scott L. Stephens,et al.  Fire Climbing in the Forest: A Semiqualitative, Semiquantitative Approach to Assessing Ladder Fuel Hazards , 2007 .

[35]  S. Stephens,et al.  Fire history and climate influences from forests in the Northern Sierra Nevada, USA , 2006 .

[36]  J. Battles,et al.  Forest Composition, Structure, and Change in an Old-Growth Mixed Conifer Forest in the Northern Sierra Nevada , 1998 .

[37]  M. Finney,et al.  Modeling wildfire risk to northern spotted owl (Strix occidentalis caurina) habitat in Central Oregon, USA , 2007 .

[38]  J. Timbrook.  Tending The Wild: Native American Knowledge and The Management of California's Natural Resources , 2006 .

[39]  Robert E. Keane,et al.  Objectives and considerations for wildland fuel treatment in forested ecosystems of the interior western United States , 2008 .

[40]  Scott L. Stephens,et al.  Challenges and Approaches in Planning Fuel Treatments across Fire-Excluded Forested Landscapes , 2010, Journal of Forestry.

[41]  Joe H. Scott,et al.  Assessing Crown Fire Potential by Linking Models of Surface and Crown Fire Behavior , 2003 .

[42]  S. Stephens,et al.  Climate change and forests of the future: managing in the face of uncertainty. , 2007, Ecological applications : a publication of the Ecological Society of America.