Treesearch
Search National Treesearch
Displaying 6,171 - 6,180 of 12,497 Publications
- National Park Service Inventory and Monitoring (I&M) networks conduct long-term monitoring to provide park managers information on the status and trends in key biological and environmental attributes (Vital Signs). Here we present an overview of a collaborative approach to long-term monitoring of high-elevation white pine forest dynamics among three Pacific West Region I&M networks: Klamath (KLMN), Sierra Nevada (SIEN), and Upper Columbia Basin (UCBN). Whitebark pine (Pinus albicaulis) is monitored in five national parks: Lassen Volcanic and Crater Lake in the KLMN, and Yosemite, Sequoia,...AuthorsShawn T. McKinney, Tom Rodhouse, Les Chow, Penelope Latham, Daniel Sarr, Lisa Garrett, Linda MutchKeywordsSourceIn: Keane, Robert E.; Tomback, Diana F.; Murray, Michael P.; Smith, Cyndi M., eds. The future of high-elevation, five-needle white pines in Western North America: Proceedings of the High Five Symposium. 28-30 June 2010; Missoula, MT. Proceedings RMRS-P-63. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 51-55.Year2011
- High elevation five-needle pines are rapidly declining throughout North America. The six species, whitebark (Pinus albicaulis Engelm.), limber (P. flexilis James), southwestern white (P. strobiformis Engelm.), foxtail (P. balfouriana Grev. & Balf.), Great Basin bristlecone (P. longaeva D.K. Bailey), and Rocky Mountain bristlecone pine (P. aristata Engelm.), have limited timber value but are of great ecological and symbolic importance to both the U.S. and Canadian West. A comprehensive International symposium, called the High Five symposium, was held June 28-30, 2010, in Missoula, Montana...AuthorsRobert E. Keane, Diana F. Tomback, Michael P. Murray, Cyndi M. SmithKeywordsSourceProceedings RMRS-P-63. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 376 p.Year2011
- The 2002 Hayman Fire was the largest fire in recent Colorado history (558 km2). The extent of high severity combustion and possible effects on Denver's water supply focussed public attention on the effects of wildfire on water quality.Wemonitored stream chemistry, temperature and sediment before the fire and at monthly intervals for 5 years after the fire. The proportional extent of a basin that was burned or that burned at high severity was closely related to post-fire streamwater nitrate and turbidity. Basins that burned at high severity on >45% of their area had twice the streamwater...AuthorsCharles C. Rhoades, Deborah Entwistle, Dana ButlerKeywordsSourceInternational Journal of Wildfire Science. 20: 430-442.Year2011
- Slash pile burning is widely conducted by land managers to dispose of unwanted woody fuels, yet this practice typically has undesirable ecological impacts. Simple rehabilitation treatments may be effective at ameliorating some of the negative impacts of pile burning on plants and soils. Here, we investigated: (1) the impacts of slash pile burning on soil nitrogen and understory plant species richness and cover in Colorado Pinus contorta Douglas ex Louden and P. contorta - Populus tremuloides Michx. stands; (2) the effectiveness of woodchip mulch and soil scarification at reversing pile...AuthorsPaula J. Fornwalt, Charles C. RhoadesSourceNatural Areas Journal. 31(2): 177-182.Year2011
- Biologic control of the introduced and invasive, woody plant tamarisk (Tamarix spp, saltcedar) in south-western states is controversial because it affects habitat of the federally endangered South-western Willow Flycatcher (Empidonax traillii extimus). These songbirds sometimes nest in tamarisk where floodplain-level invasion replaces native habitats. Biologic control, with the saltcedar leaf beetle (Diorhabda elongate), began along the Virgin River, Utah, in 2006, enhancing the need for comprehensive understanding of the tamarisk-flycatcher relationship. We used maximum entropy (Maxent)...AuthorsPatricia York, Paul Evangelista, Sunil Kumar, James Graham, Curtis H. Flather, Thomas StohlgrenKeywordsSourceFrontiers of Earth Science. 5(2): 120-129.Year2011
- Wetlands generally provide significant ecosystem services and function as important harbors of biodiversity. To ensure that these habitats are conserved, an efficient means of identifying wetlands at risk of conversion is needed, especially in the southern United States where the rate of wetland loss has been highest in recent decades. We used multivariate adaptive regression splines to develop a model to predict the risk of wetland habitat loss as a function of wetland features and landscape context. Fates of wetland habitats from 1992 to 1997 were obtained from the National Resources...AuthorsKevin J. Gutzwiller, Curtis H. FlatherKeywordsSourceEcological Applications. 21(3): 968-982.Year2011
- Establishing species conservation priorities and recovery goals is often enhanced by extinction risk estimates. The need to set goals, even in data-deficient situations, has prompted researchers to ask whether general guidelines could replace individual estimates of extinction risk. To inform conservation policy, recent studies have revived the concept of the minimum viable population (MVP), the population size required to provide some specified probability of persistence for a given period of time. These studies conclude that long-term persistence requires ≥5000 adult individuals, an MVP...AuthorsCurtis H. Flather, Gregory D. Hayward, Steven R. Beissinger, Philip A. StephensSourceTrends in Ecology and Evolution. 26(6): 307-316.Year2011
- We characterized the water chemistry of nine slope wetlands and adjacent headwater streams in Colorado subalpine forests and compared sites in basins formed on crystalline bedrock with those formed in basins with a mixture of crystalline and sedimentary bedrock. The pH, Ca2+, Mg2+, NH4 +, acid neutralizing capacity, and electrical conductivity of wetland porewater and streamwater were higher in the basins with mixed geology. Bryophyte cover was higher in lower pH, crystalline basins, and vascular plant cover was higher in the mixed bedrock basins. On average, wetland porewater had lower pH...AuthorsMonique LaPerriere Nelson, Charles C. Rhoades, Kathleen A. DwireKeywordsSourceWetlands. 31: 251-261.Year2011
- Available air temperature models do not adequately account for the influence of terrain on nocturnal air temperatures. An empirical model for night time air temperatures was developed using a network of one hundred and forty inexpensive temperature sensors deployed across the Bitterroot National Forest, Montana. A principle component analysis (PCA) on minimum temperatures showed that 98% of the spatiotemporal variability could be accounted for using the first two modes which described the coupling and decoupling of surface temperature from free air temperatures, respectively. The spatial...AuthorsJohn T. Abatzoglou, Zachary A. Holden, Charlie H. Luce, L. Scott BaggettKeywordsSourceAgricultural and Forest Meteorology. 151: 1066-1073.Year2011
- Many forestry and earth science applications require spatially detailed forest height data sets. Among the various remote sensing technologies, lidar offers the most potential for obtaining reliable height measurement. However, existing and planned spaceborne lidar systems do not have the capability to produce spatially contiguous, fine resolution forest height maps over large areas. This paper describes a Landsat-lidar fusion approach for modeling the height of young forests by integrating historical Landsat observations with lidar data acquired by the Geoscience Laser Altimeter System...AuthorsAinong Li, Chengquan Huang, Guoqing Sun, Hua Shi, Chris Toney, Zhiliang Zhu, Matthew G. Rollins, Samuel N. Goward, Jeffrey G. MasekKeywordsSourceRemote Sensing of Environment. 115(8): 1837-1849.Year2011