Treesearch
Search National Treesearch
Displaying 981 - 990 of 6,800 Publications
- This guidebook describes major biological and physical attributes of the 2686-ha (6,637-ac) Black Canyon Research Natural Area (RNA), Wheeler County, Oregon. The RNA contains high-quality examples of native plant associations’ representative of the foothills of the Blue Mountains ecoregion.AuthorsReid Schuller, Sarah CanhamKeywordsSourceGen. Tech. Rep. PNW-GTR-969. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 25 p.Year2019
- Recent predictions of hyporheic exchange at the basin‐scale assume individual features control exchange independently of each other, which has been demonstrated in relatively uniform, low‐gradient rivers. However, this assumption may not hold in steep catchments where both the type and size of individual features may vary over short distances, leading to irregular patterns of feature dominance on hyporheic exchange flows. Also, steep longitudinal gradients support substantial downvalley flows in the subsurface, which may create feedbacks between adjacent features. In this study, we test...AuthorsSkuyler P. Herzog, Adam S. Ward, Steve WondzellKeywordsSourceWater Resources Research. 55(12): 10976-10992.Year2019
Spatial and temporal variation in river corridor exchange across a 5th-order mountain stream network
Although most field and modeling studies of river corridor exchange have been conducted at scales ranging from tens to hundreds of meters, results of these studies are used to predict their ecological and hydrological influences at the scale of river networks. Further complicating prediction, exchanges are expected to vary with hydrologic forcing and the local geomorphic setting. While we desire predictive power, we lack a complete spatiotemporal relationship relating discharge to the variation in geologic setting and hydrologic forcing that is expected across a river basin. Indeed, the...AuthorsAdam S. Ward, Steve Wondzell, Noah M. Schmadel, Skuyler Herzog, Jay P. Zarnetske, Viktor Baranov, Phillip J. Blaen, Nicolai Brekenfeld, Rosalie Chu, Romain Derelle, Jennifer Drummond, Jan H. Fleckenstein, Vanessa Garayburu-Caruso, Emily Graham, David Hannah, Ciaran J. Harman, Jase Hixson, Julia L. A. Knapp, Stefan Krause, Marie J. Kurz, Jörg Lewandowski, Angang Li, Eugènia Martí, Melinda Miller, Alexander M. Milner, Kerry Neil, Luisa Orsini, Aaron I Packman, Stephen Plont, Lupita Renteria, Kevin Roche, Todd Royer, Catalina Segura, James Stegen, Jason Toyoda, Jacqueline Wells, Nathan I WisnoskiSourceHydrology and Earth System Sciences. 23(12): 5199-5225.Year2019- A comprehensive set of measurements and calculated metrics describing physical, chemical, and biological conditions in the river corridor is presented. These data were collected in a catchment-wide, synoptic campaign in the H. J. Andrews Experimental Forest (Cascade Mountains, Oregon, USA) in summer 2016 during low-discharge conditions. Extensive characterization of 62 sites including surface water, hyporheic water, and streambed sediment was conducted spanning 1st- through 5th-order reaches in the river network. The objective of the sample design and data acquisition was to generate a...AuthorsAdam S. Ward, Jay P. Zarnetske, Viktor Baranov, Phillip J. Blaen, Nicolai Brekenfeld, Rosalie Chu, Romain Derelle, Jennifer Drummond, Jan H. Fleckenstein, Vanessa Garayburu-Caruso, Emily Graham, David Hannah, Ciaran J. Harman, Skuyler Herzog, Jase Hixson, Julia L. A. Knapp, Stefan Krause, Marie J. Kurz, Jörg Lewandowski, Angang Li, Eugènia Martí, Melinda Miller, Alexander M. Milner, Kerry Neil, Luisa Orsini, Aaron I Packman, Stephen Plont, Lupita Renteria, Kevin Roche, Todd Royer, Noah M. Schmadel, Catalina Segura, James Stegen, Jason Toyoda, Jacqueline Wells, Nathan I Wisnoski, Steve WondzellKeywordsSourceEarth System Science Data. 11(4): 1567-1581.Year2019
- The relationship between carbon burial and sedimentation in reservoirs is unknown, contributing to uncertainty in our understanding of the net impact of dams to the global carbon budget and exposing gaps in our fundamental understanding of the transport, processing, and deposition of organic matter in fluvial and lacustrine systems. Taking opportunistic advantage of the removal of two high‐head dams, we investigate this relationship by developing a stratigraphic, process‐based framework to estimate total carbon accumulation as a function of depositional environment in the sediments of two...AuthorsLaurel E. Stratton, Roy Haggerty, Gordon GrantKeywordsSourceJournal of Geophysical Research: Earth Surface. 124(8): 2118-2140.Year2019
- Phenology can be linked to individual fitness, particularly in strongly seasonal environments where the timing of events has important consequences for growth, condition, and survival. We studied the phenology of coho salmon (Oncorhynchus kisutch) hatching and emergence in streams with contrasting thermal variability but in close geographic proximity. Following emergence, we tracked body sizes of cohorts of young-of-year fish until the end of the growing season. Hatch and emergence occurred at the same time among streams with marked variability in thermal regimes. We demonstrate that this...AuthorsEmily Y. Campbell, Jason B. Dunham, Gordon Reeves, Steve WondzellKeywordsSourceCanadian Journal of Fisheries and Aquatic Sciences. 76(2): 185-191.Year2019
- At the ecosystem scale, water-use efficiency (WUE) is defined broadly as the ratio of carbon assimilated to water evaporated by an ecosystem. WUE is an important aspect of carbon and water cycling and has been used to assess forest ecosystem responses to climate change and rising atmospheric CO2 concentrations. This study investigates the influence of meteorological and radiation variables on forest WUE by analyzing an 18 year (1998–2015) half-hourly time series of carbon and water fluxes measured with the eddy covariance technique in an old-growth conifer forest in the Pacific Northwest,...AuthorsYueyang Jiang, Christopher Still, Bharat Rastogi, Gerald Page, Sonia Wharton, Frederick Meinzer, Steven Voelker, John B. KimKeywordsSourceEnvironmental Research Letters. 14(7): 074029.Year2019
- Natural resource advisors operate at a natural resource-climate nexus that presents opportunity for utilization of regionally relevant climate science and tools to support climate smart decision making among land managers. This opportunity, however, may be underutilized. In thousands of county offices across the country, USDA field staff with the Natural Resources Conservation Service (NRCS) and Farm Service Agency (FSA) interface with farmers on a daily basis to provide conservation technical assistance, farm loans, and disaster recovery assistance. In this study, we conducted a survey of...AuthorsS. Wiener, G.E. Roesch-McNally, R.E. Schattman, M.T. NilesKeywordsSourceJournal of Soil and Water Conservation. 75(1): 62-74.Year2019
- The American West exists in the popular imagination as a distinct region, and policies and politics often suggest that both the challenges and the opportunities for land management and human well-being across the region are relatively homogeneous. In this paper, we argue that there are key characteristics that define the West as a social-ecological region, and also that there are myriad social-ecological systems (SESs) within the region that require diverse and dynamic approaches to managing change over time. We first conceptualize aridity, topography, and a unique political economy of...AuthorsKristal Jones, Jesse Abrams, R Travis Belote, Bray Beltrán, Jodi Brandt, Neil Carter, Antonio Castro, Brian Chaffin, Alexander Metcalf, Gabrielle Roesch-McNally, Kenneth Wallen, Matthew A. WilliamsonSourceEnvironmental Research Letters. 14(11): 115008.Year2019
- Climate change is altering the conditions for tree recruitment, growth, and survival, and impacting forest community composition. Across southeast Alaska, USA, and British Columbia, Canada, Callitropsis nootkatensis (Alaska yellow‐cedar) is experiencing extensive climate change‐induced canopy mortality due to fine‐root death during soil freezing events following warmer winters and the loss of insulating snowpack. Here, we examine the effects of ongoing, climate‐driven canopy mortality on forest community composition and identify potential shifts in stand trajectories due to the loss of a...AuthorsSarah M. Bisbing, Brian J. Buma, Lauren E. Oakes, John Krapek, Allison L. BidlackKeywordsSourceEcology and Evolution. 9(14): 8157-8174.Year2019