Treesearch
Search National Treesearch
Displaying 2,661 - 2,670 of 6,856 Publications
- Herein, we summarize our work, within forest ecosystems of Garo Hills in northeast India, on mapping vegetation and land cover conditions, delineating wildlife habitat corridors among protected areas, evaluating forest conservation values of influence zones bordering protected areas, analyzing dispersion patterns of native forests, and determining potential effects of shifting-cultivation agriculture and anthropogenic stressors on an umbrella species (Asian elephant) as an indicator of forest biodiversity. This work demonstrates our use of multiple geoinformatic methods to help advise on...AuthorsAshish Kumar, Bruce G. Marcot, Gautam Talukdar, P.S. RoyKeywordsSourceAsian Journal of Geoinformatics. 12(1): 13 pYear2012
- The bull trout Salvelinus confluentus is an apex predator in native fish communities in the western USA and is listed as threatened under the U.S. Endangered Species Act (ESA). Restoration of this species has raised concerns over its potential predatory impacts on native fish fauna. We held a five-person expert panel to help determine potential impacts of reintroducing bull trout into the Clackamas River, northwest Oregon, on the viability of four anadromous salmonid populations that are listed as threatened under the ESA: spring and fall Chinook salmon Oncorhynchus tshawytscha, coho...AuthorsBruce G. Marcot, Chris S. Allen, Steve Morey, Dan Shively, Rollie WhiteKeywordsSourceNorth American Journal of Fisheries Management. 32: 450-465Year2012
- Retreating glaciers and the periglacial areas that they vacate produce a harsh environment of extreme radiation, nutrient limitations and temperature oscillations. They provide a model system for studying mechanisms that drive the establishment and early assembly of communities. Here, we synthesize more than 20 years of research at the Lyman Glacier forefront in the North Cascades Mountains, comparing the results and conclusions for plant and fungal communities. Compared to plant communities, the trajectories and processes of fungal community development are difficult to deduce. However, a...AuthorsAri Jumpponen, Shawn P. Brown, James M. Trappe, Efrén Cázares, Rauni StrömmerKeywordsSourceFungal Ecology. 5(4): 430-442Year2012
- Provenance-specific variation in bark thickness in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is important for accurate volume calculations and might carry ecological implications as well. To investigate variation, diameter at breast height (dbh) and double bark thickness (dbt) were measured in 10 experiments in southwestern Germany (16 American and 6 German seed sources), which were approximately 50 years old and ranged in productivity. Provenance-specific mixed models for dbt versus dbh varied considerably with respect to intercept and slope. Likewise, analysis of covariance on...AuthorsUlrich Kohnle, Sebastian Hein, Frank Sorensen, Aaron R. WeiskittelSourceCanadian Journal of Forestry Research. 42: 382-399Year2012
- Hydraulic conductance of leaves (Kleaf) typically decreases with increasing water stress and recent studies have proposed different mechanisms responsible for decreasing Kleaf. We measured Kleaf concurrently with ultrasonic acoustic emissions (UAEs) in dehydrating leaves of several species to determine whether declining Kleaf was associated with xylem embolism. In addition, we performed experiments in which the surface tension of water in the leaf xylem was reduced by using a surfactant solution. Finally, we compared the hydraulic vulnerability of entire leaves with the leaf lamina in...AuthorsDaniel Johnson, Katherine A. McCulloh, David R. Woodruff, Frederick MeinzerKeywordsSourcePlant, Cell and Environment. 35: 760-769Year2012
- This report traces the flow of Oregon’s 2008 timber harvest through the primary timber processing industry and provides a description of the structure, operation, and condition of Oregon’s forest products industry as a whole. It is the second in a series of reports that update the status of the industry every 5 years. Based on a census conducted in 2009 and 2010, we provide detailed information about the industry in 2008, and discuss historical changes as well as more recent trends in harvest, production, and sales. To convey the severe market and economic conditions that existed in 2008,...AuthorsCharles B. Gale, Charles E. Keegan, Erik C. Berg, Jean Daniels, Glenn Christensen, Colin B. Sorenson, Todd A. Morgan, Paul PolzinKeywordsSourceGen. Tech. Rep. PNW-GTR-868. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 55 pYear2012
- There has been increasing interest in the use of market-based approaches to add value for forestland and to assist with the conservation of natural resources. While markets for ecosystem services show potential for increasing forestland value, there is concern that the lack of an integrated program will simply add to the complexity of these services without generating significant public benefits. If not designed properly, these fragmented programs can result in the restoration of many small sites that lack ecological integrity and are unlikely to provide the benefits from protecting larger...AuthorsRobert Deal, Bobby Cochran, Gina LaRoccoSourceForest Policy and Economics. 17: 69-76Year2012
- Around the world forests provide a broad range of vital ecosystem services. Sustainable forest management and forest products play an important role in global carbon management, but one of the major forestry concerns worldwide is reducing the loss of forestland from development. Currently, deforestation accounts for approximately 20% of total greenhouse gas emissions. Furthermore, recent evaluation of the state of the world's ecosystems shows that about 60% of all ecosystems are rapidly degrading or are being used unsustainably. As a result, the rationale for quantifying and valuing...AuthorsRobert Deal, Rachel WhiteSourceForest Policy and Economics. 17: 1-2Year2012
- Aquatic ecologists are working to develop theory and techniques for analysis of dynamic stream processes and communities of organisms. Such work is critical for the development of conservation plans that are relevant at the scale of entire ecosystems. The stream network is the foundation upon which stream systems are organized. Natural and human disturbances in streams alter the configuration of stream habitats such as pools, riffles, and glides across seasons, decades, or centuries. Thus, native aquatic species have developed mechanisms for adapting to the dynamic configuration of...AuthorsRebecca Flitcroft, Kelly Burnett, Gordon Reeves, Lisa M. GanioKeywordsSourceAquatic Conservation: Marine and Freshwater Ecosystems. 22: 288-302Year2012
- Cofiring of biomass and coal at electrical generation facilities is gaining in importance as a means of reducing fossil fuel consumption, and more than 40 facilities in the United States have conducted test burns. Given the large size of many coal plants, cofiring at even low rates has the potential to utilize relatively large volumes of biomass. This could have important forest management implications if harvest residues or salvage timber are supplied to coal plants. Other feedstocks suitable for cofiring include wood products manufacturing residues, woody municipal wastes, agricultural...AuthorsJohn Zerbe, David L. NichollsKeywordsSourcePNW-GTR-867. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 22 pYear2012