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- Modelling techniques used in binary classification problems often result in a predicted probability surface, which is then translated into a presence - absence classification map. However, this translation requires a (possibly subjective) choice of threshold above which the variable of interest is predicted to be present. The selection of this threshold value can have dramatic effects on model accuracy as well as the predicted prevalence for the variable (the overall proportion of locations where the variable is predicted to be present). The traditional default is to simply use a threshold...AuthorsElizabeth Freeman, Gretchen MoisenKeywordsSourceEcological Modelling. 217: 48-58.Year2008
- The occurrence and abundance of conifers along climate gradients in the Inland Northwest (USA) was assessed using data from 5082 field plots, 81% of which were forested. Analyses using the Random Forests classification tree revealed that the sequential distribution of species along an altitudinal gradient could be predicted with reasonable accuracy from a single climate variable, a growing-season dryness index, calculated from the ratio of degreedays .58C that accumulate in the frost-free season to the summer precipitation. While the appearance and departure of species in an ascending...AuthorsGerald Rehfeldt, Dennis E. Ferguson, Nicholas L. CrookstonKeywordsSourceEcology. 89(8): 2127-2139.Year2008
- This state-of-knowledge review of information on relationships between wildland fire and nonnative invasive plants can assist fire managers and other land managers concerned with prevention, detection, and eradication or control of nonnative invasive plants. The 16 chapters in this volume synthesize ecological and botanical principles regarding relationships between wildland fire and nonnative invasive plants, identify the nonnative invasive species currently of greatest concern in major bioregions of the United States, and describe emerging fire-invasive issues in each bioregion and...AuthorsKristin L. Zouhar, Jane Kapler Smith, Steve Sutherland, Matthew L. BrooksKeywordsSourceGen. Tech. Rep. RMRS-GTR-42-vol. 6. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 355 p.Year2008
- This article introduces yaImpute, an R package for nearest neighbor search and imputation. Although nearest neighbor imputation is used in a host of disciplines, the methods implemented in the yaImpute package are tailored to imputation-based forest attribute estimation and mapping. The impetus to writing the yaImpute is a growing interest in nearest neighbor imputation methods for spatially explicit forest inventory, and a need within this research community for software that facilitates comparison among different nearest neighbor search algorithms and subsequent imputation techniques....AuthorsNicholas L. Crookston, Andrew O. FinleyKeywordsSourceJournal of Statistical Software. 23(10). 16 p.Year2008
- The National Forest System (NFS) is composed of 155 national forests (NFs) and 20 national grasslands (NGs), which encompass a wide range of ecosystems, harbor much of the nation’s biodiversity, and provide myriad goods and services. The mission of the U.S. Forest Service (USFS), which manages the NFS, has broadened from water and timber to sustaining ecosystem health, diversity, and productivity to meet the needs of present and future generations. The evolution of this mission reflects changing societal values (e.g., increasing emphasis on recreation, aesthetics, and biodiversity conservat...AuthorsLinda A. Joyce, Geoffry M. Blate, Jeremy S. Littell, Steven G. McNulty, Connie I. Millar, Susanne C. Moser, Ronald P. Neilson, Kathy O'Halloran, David L. PetersonKeywordsSourceIn: Julius, S.H.; West, J.M., eds. Preliminary review of adaptation options for climate-sensitive ecosystems and resources. Synthesis and Assessment Product 4.4. Washington, DC: U.S. Environmental Protection Agency, Climate Change Science Program: p. 3-1 to 3-127Year2008
- This report provides a preliminary review of adaptation options for climate-sensitive ecosystems and resources in the United States. The term “adaptation” in this document refers to adjustments in human social systems (e.g., management) in response to climate stimuli and their effects. Since management always occurs in the context of desired ecosystem conditions or natural resource management goals, it is instructive to examine particular goals and processes used by different organizations to fulfill their objectives. Such an examination allows for discussion of specific adaptation options...AuthorsSusan H. Julius, Jordan M. West, Geoffrey M. Blate, Jill S. Baron, Brad Griffith, Linda A. Joyce, Peter Kareiva, Brian D. Keller, Margaret A. Palmer, Charles Peterson, J. Michael ScottKeywordsSourceIn: Julius, S.H.; West, J.M., eds. Preliminary review of adaptation options for climate-sensitive ecosystems and resources. Synthesis and Assessment Product 4.4. Washington, DC: U.S. Environmental Protection Agency, Climate Change Science Program: p. 1-1 to 1-6Year2008
- The Great Basin Native Plant Selection and Increase Project, organized by the USDA Bureau of Land Management, Great Basin Restoration Initiative and the USDA Forest Service, Rocky Mountain Research Station in 2000 as a multi-agency collaborative program (https://www.fs.usda.gov/rm/boise/research/shrub/greatbasin.shtml), has the objective of improving the availability of native plant materials and providing the knowledge and technology required for their use in restoring diverse native plant communities in the Great Basin of the western United States. Lands within the 55 million ha region...AuthorsN. L. Shaw, M. Pellant, P. Olweli, S. L. Jensen, E. D. McArthurSourceIn: Multifunctional grasslands in a changing world, Volume II; XXI International Grassland Congress; VIII International Rangeland Congress. Beijing, China: Guangdong People's Publishing House: 454Year2008
- Forests store much carbon and their growth can be a carbon sink if disturbance or harvesting has killed or removed trees or if trees that can now regrow are planted where they did not historically occur. Forests and long-lived wood products currently offset 310 million metric tons of U.S. fossil fuel emissions of carbon--20 percent of the total (Pacala et al. 2007). This is an enormous ecosystem service; Jackson and Schlesinger (2004) estimated that offsetting another 10 percent of emissions would require the conversion of one-third of our current U.S. cropland to forest plantations. Large...AuthorsMichael G. RyanKeywordsSource(June 04, 2008). U.S. Department of Agriculture, Forest Service, Climate Change Resource Center. http://www.fs.fed.us/ccrc/topics/carbon.shtml [July 16, 2008].Year2008
- In the last 20 years, wildfire damages and the costs of wildfire suppression have risen dramatically. This trend has been attributed to three main factors: climate change, increased fuel loads from a century of wildfire suppression, and increased housing development in fire-prone areas., There is little that fire managers can do about climate change, and current fuel management budgets struggle to keep pace with fuel accumulation, let alone correct it. Thus, if wildfire costs and damages are to be controlled, efforts need to focus on mitigating wildfire risk near housing developments in...AuthorsPatricia A. Champ, Geoffrey Donovan, Christopher BarthKeywordsSourceRural connections. 2(3): 5-6.Year2008
- This publication has been removed. On July 1, 2009, the United States District Court for the District of Idaho issued a decision and order in Idaho Wool Growers Assoc. v. Schafer which found that the Risk Assessment Disease Transmission Committee and the Payette Principles Committee were advisory committees subject to the procedural requirements of FACA. These Committees were established to review information regarding disease transmission between domestic and bighorn sheep for a Forest Planning effort. The order states that "the Committees' finding and /or conclusions are not to be relied...AuthorsTimothy J. Schommer, Melanie M. WooleverSourceGen. Tech. Rep. RMRS-GTR-209 Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 16 p.Year2008