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- We observed habitat occupancy by juvenile Chinook salmon (Oncorhynchus tschawytscha) and steelhead trout (Oncorhynchus mykiss) at in-stream habitat restoration structures constructed in the Entiat River, Washington, USA. In 2009–2013, fish abundance measurements during rearing (July–October) showed high temporal variability in pools with restoration structures. Both species were more abundant at restored pools than at natural pools in early summer (July), but this difference was typically absent by September. Fish response to restoration structures also varied across years. When looking...AuthorsCarlos M. Polivka, Ashley Steel, Jenni L. Novak, Bror JonssonSourceCanadian Journal of Fisheries and Aquatic Sciences. 72(2): 166-174.Year2015
- Accurate biomass measurements and analyses are critical components in quantifying carbon stocks and sequestration rates, assessing potential impacts due to climate change, locating bio-energy processing plants, and mapping and planning fuel treatments. To this end, biomass equations will remain a key component of future carbon measurements and estimation. As researchers in biomass and carbon estimation, we review the present scenario of aboveground biomass estimation, focusing particularly on estimation using tree-level models and identify some cautionary points that we believe will...AuthorsHailemariam Temesgen, David Affleck, Krishna Poudel, Andrew Gray, John SessionsKeywordsSourceScandinavian Journal of Forest Research. 30(4): 326-335.Year2015
- The physical and chemical environment of the Earth has changed rapidly over the last 100 years and is predicted to continue to change into the foreseeable future. One of the main concerns with potential alterations in climate is the propensity for increases in the magnitude and frequency of extremes to occur. Even though precipitation is predicted to increase in some locations, in others precipitation is expected to decrease and evapotranspiration increase with air temperature, resulting in exacerbated drought in the future. Chemical [ozone (O3) and other air contaminants] and subsequent...AuthorsA. H. Chappelka, Nancy E. Grulke, L. De KokSourcePlant BiologyYear2015
- Climate change models are predicting increased frequency and severity of droughts in arid and semiarid environments, and these areas are responsible for much of the world’s livestock production. Because cattle (Bos Taurus) grazing can impact the abundance, distribution, and ecological function of native plant and animal communities, it is important to understand how cattle might respond to increasingly arid conditions. Here, we evaluate changes in habitat selection by cattle across an 8-yr period as a function of rainfall and other environmental covariates. Using resource selection...AuthorsC. L. Roever, T. DelCurto, Mary M. Rowland, Marty Vavra, Michael WisdomKeywordsSourceJournal of Animal Science. 93(6): 3212-.Year2015
- Viewing peaceful natural environments has been shown to restore cognitive abilities and reduce physiological arousal. As such, visual access to the natural environment is becoming more commonplace in built environments. One exception to that trend is in educational settings where windowless classrooms are used to reduce outside distractions. The current study examines differences across multiple sections of a college writing course in two types of identically designed classrooms—those with a view of a natural setting and those with a view of a concrete retaining wall. Results showed that...AuthorsJ.A. Benfield, G.N. Rainbolt, P.A. Bell, Geoffrey DonovanKeywordsSourceEnvironment and Behavior. 47(2): 140-157.Year2015
- Predictive relationships between soil drainage and soil morphological features are essential for understanding hydromorphic processes in soils. The linkage between patterns of soil saturation, reduction, and reductimorphic soil properties has not been extensively studied in mountainous forested terrain. We measured soil saturation and reduction during a 4-yr period in three catenas of the perhumid coastal temperate rainforest of Alaska and compared these measurements to soil morphological features of Spodosols and Histosols. Soil saturation and anaerobic conditions indicated by redox...AuthorsDavid V. D'Amore, Chien-Lu Ping, Paul HerendeenSourceSoil Science Society of America Journal. 79(2): 698-709.Year2015
- Questions: Are exotic plant species favoured by non-native ungulate herbivores and disadvantaged by native herbivores in forested rangelands? Do the impacts of ungulates on exotic vs native plants depend on forest management activities such as prescribed fire and stand thinning? Location: Northeastern Oregon, USA. Methods: We recorded changes in richness and cover of different exotic and native plant life forms in experimental plots that were grazed only by cattle (a non-native herbivore), only by elk (a native herbivore) or not grazed by any ungulate over a 7-yr period at bothmanaged...AuthorsBurak K. Pekin, Michael Wisdom, Catherine Parks, Bryan A. Endress, Bridgett Naylor, Ralf OhlemullerKeywordsSourceApplied Vegetation ScienceYear2015
- Climate impact studies often require the selection of a small number of climate scenarios. Ideally, a subset would have simulations that both (1) appropriately represent the range of possible futures for the variable/s most important to the impact under investigation and (2) come from global climate models (GCMs) that provide plausible results for future climate in the region of interest.We demonstrate an approach to select a subset of GCMs that incorporates both concepts and provides insights into the range of climate impacts. To represent how an ecosystem process responds to projected...AuthorsJulie A. Vano, John B. Kim, David E. Rupp, Philip W. MoteSourceGeophysical Research Letters. 42(13): 5516-5525.Year2015
- We reviewed the literature to synthesize what is known about the use of fire to maintain and restore oak forests, woodlands, and savannas of the upper Midwestern United States, with emphasis on Minnesota, Wisconsin, and Michigan. Included are (1) known physical and ecological effects of fire on oaks from acorn through seedling, established sapling, and mature stages of the life cycle; (2) the use of fire to modify competitive interactions between oaks and mesic forest species (e.g., maple), between oaks and pines, and between oaks and grasses; (3) interaction of fire with other disturbances...AuthorsLee E. Frelich, Peter B. Reich, David W. PetersonKeywordsSourceGen. Tech. Rep. PNW-GTR-914. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 64 p.Year2015
- Current and future human and forest landscape conditions are influenced by the cumulative, unfolding history of socialecological interactions. Examining past system responses, especially unintended consequences, can reveal valuable insights that promote learning and adaptation in forest policy and management. Temporal couplings are complex, however; they can be difficult to trace, characterize, and explain. We develop a framework that integrates environmental history into analysis of coupled human and natural systems (CHANS). Our study demonstrates how historical data and methods can help...AuthorsMichelle M. Steen-Adams, Nancy Langston, Mark D. O. Adams, David J. MladenoffKeywordsSourceEcology and Society. 20(1): 1-28.Year2015