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- The U.S. Forest Service has adopted the concept and language of ecosystem services to describe the beneficial outcomes of national forest management. We review the economic theory of ecosystem services as it applies to public lands management, and consider what it implies about the types of biophysical and other data that are needed for characterizing management outcomes as changes in ecosystem services. Our intent is to provide a guide to policymakers, managers, researchers, and others for evaluating and describing the tradeoffs involved in the management of public lands. Characterizing...AuthorsJeffrey D. Kline, Marisa J. MazzottaKeywordsSourceGen. Tech. Rep. PNW-GTR-865. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 48 pYear2012
- Tree canopy cover is a fundamental component of the landscape, and the amount of cover influences fire behavior, air pollution mitigation, and carbon storage. As such, efforts to empirically model percent tree canopy cover across the United States are a critical area of research. The 2001 national-scale canopy cover modeling and mapping effort was completed in 2006, and here we present results from a pilot study for a 2011 product. We examined the influence of two different modeling techniques (random forests and beta regression), two different Landsat imagery normalization processes, and...AuthorsJohn W. Coulston, Gretchen Moisen, Barry T. (Ty) Wilson, Mark V. Finco, Warren B. Cohen, Ken BrewerKeywordsSourcePhotogrammetric Engineering & Remote Sensing 78(7): 715–727Year2012
- In this article, our objective is to introduce economics as a tool for the planning, prioritization, and evaluation of restoration projects. Studies that develop economic estimates of public values for ecological restoration employ methods that may be unfamiliar to practitioners. We hope to address this knowledge gap by describing economic concepts in the context of ecological restoration. We have summarized the most common methods for estimating the costs and benefits of restoration projects as well as frameworks for decision analysis and prioritization. These methods are illustrated in a...AuthorsJean Daniels, Alicia S.T. RobbinsKeywordsSourceRestoration Ecology. 20(1): 10-17Year2012
- Red foxes (Vulpes vulpes) are native to boreal and western montane portions of North America but their origins are unknown in many lowland areas of the United States. Red foxes were historically absent from much of the East Coast at the time of European settlement and did not become common until the mid-1800s. Some early naturalists described an apparent southward expansion of native foxes that coincided with anthropogenic habitat changes in the region. Alternatively, red foxes introduced from Europe during Colonial times may have become established in the east and subsequently expanded...AuthorsBenjamin N. Sacks, Mark J. Statham, Keith B. Aubry, John D. Perrine, Samantha M. WiselyKeywordsSourceJournal of Mammalogy. 93(1): 52-65Year2012
- Spatial maps of density and stiffness patterns within individual trees were developed using two methods: (1) measured wood properties of veneer sheets; and (2) mixed effects models, to test the hypothesis that within-tree patterns could be predicted from easily measurable tree variables (height, taper, breast-height diameter, and acoustic velocity). Sample trees comprised an assortment of 25 coastal Pacific Northwest Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees grown on three sites under a range of thinning regimes. At harvest, trees were 36 years old on one site, and 45 and 51...AuthorsEini C. Lowell, Dennis Dykstra, David G. Briggs, Christine L. TodorokiKeywordsSourceSCION. 42: 1-13Year2012
- Tensile properties of strands processed from small-diameter Douglas-fir and western hemlock trees grown on the Washington coast were analyzed and effects of location within the tree on properties was examined. Reduction factors for strand properties relative to small, clear solid wood specimen properties were determined by correlating strand properties to previously examined small, clear solid wood specimen properties from the same set of trees. These reductions can be assumed to be damage reduction factors that could help in understanding the expected reduction in tensile or flexure...AuthorsVikram Yadama, Eini C. Lowell, Christopher E. LangumKeywordsSourceWood and Fiber Science. 44(1): 36-45Year2012
- Plume injection height influences plume transport characteristics, such as range and potential for dilution. We evaluated plume injection height from a predictive wildland fire smoke transport model over the contiguous United States (U.S.) from 2006 to 2008 using satellite-derived information, including plume top heights from the Multi-angle Imaging SpectroRadiometer (MISR) Plume Height Climatology Project and aerosol vertical profiles from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). While significant geographic variability was found in the comparison between modeled...AuthorsSean M. Raffuse, Kenneth J. Craig, Sim Larkin, Tara Strand, Dana Coe Sullivan, Neil J.M. Wheeler, Robert SolomonKeywordsSourceAtmosphere. 3: 103-123. DOI:10.3390/atmos3010103Year2012
- Riparian buffers provide improved protection for water quality and biota, and narrow, fixed-width buffers of native vegetation along streams have been used to mitigate the effects of forest harvest at least since the 1960s. The practice of leaving unmanaged strips of vegetation along water courses in agricultural lands had been used before the 1960s in southern Europe and in eastern North America, but the scientific basis for leaving riparian buffers on forested lands came from observations in the coastal temperate rainforests of western North America. Those observations often were applied...AuthorsRobert J. Naiman, Pete Bisson, John S. RichardsonSourceFreshwater Science. 31(1): 232-238Year2012
- Wildfires are increasingly emerging as an important component of Earth system models, particularly those that involve emissions from fires and their effects on climate. Currently, there are few resources available for estimating emissions from wildfires in real time, at subcontinental scales, in a spatially consistent manner. Developing subcontinental-scale databases and applications in fire science requires a framework that uses both fine-scale and coarse-scale data with attention to minimizing extrapolation errors, while ensuring spatial consistency in outputs. The estimation of actual...AuthorsNancy H.F. French, Roger D. Ottmar, Donald McKenzieKeywordsSourceEos. 93(6): 57-58Year2012
- Understanding the environmental controls on historical wildfires, and how they changed across spatial scales, is difficult because there are no surviving explicit records of either weather or vegetation (fuels). Here we show how power laws associated with fire-event time series arise in limited domains of parameters that represent critical transitions in the controls on landscape fire. Comparison to a self-organized criticality model shows that the latter mimics historical fire only in a limited domain of criticality, and is not an adequate mechanism to explain landscape fire dynamics,...AuthorsDonald McKenzie, Maureen C. KennedyKeywordsSourceNature Communications. 3. 6 p. DOI: 10.1038/ncomms1731Year2012