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- Advancing phenology is one of the most visible effects of climate change on plant communities, and has been especially pronounced in temperature-limited tundra ecosystems. However, phenological responses have been shown to differ greatly between species, with some species shifting phenology more than others. We analysed a database of 42,689 tundra plant phenological observations to show that warmer temperatures are leading to a contraction of community-level flowering seasons in tundra ecosystems due to a greater advancement in the flowering times of late-flowering species than early-flower...AuthorsJanet S. Prevey, Christian Rixen, Nadja Rüger, Toke T. Høye, Anne D. Bjorkman, Isla H. Myers-Smith, Sarah C. Elmendorf, Isabel W. Ashton, Nicoletta Cannone, Chelsea L. Chisholm, Karin Clark, Elisabeth J. Cooper, Bo Elberling, Anna Maria Fosaa, Greg H. R. Henry, Robert D. Hollister, Ingibjörg Svala Jónsdóttir, Kari Klanderud, Christopher W. Kopp, Esther Lévesque, Marguerite Mauritz, Ulf Molau, Susan M. Natali, Steven F. Oberbauer, Zoe A. Panchen, Eric Post, Sabine B. Rumpf, Niels Martin Schmidt, Edward Schuur, Philipp R. Semenchuk, Jane G. Smith, Katharine N. Suding, Ørjan Totland, Tiffany Troxler, Susanna Venn, Carl-Henrik Wahren, Jeffrey M. Welker, Sonja WipfKeywordsSourceNature Ecology & Evolution. 3(1): 45-52.Year2019
- The Northwest Forest Plan (NWFP) initiated one of the most sweeping changes to forest management in the world, affecting 10 million hectares of federal land. The NWFP is a science-based plan incorporating monitoring and adaptive management and provides a unique opportunity to evaluate the influence of policy. We used >25 years of region-wide bird surveys, forest data, and landownership maps to test this policy’s effect on biodiversity. Clearcutting decreased rapidly, and we expected populations of olderforest– associated birds to stabilize on federal land, but to continue declining on...AuthorsBenjamin T. Phalan, Joseph M. Northrup, Zhiqiang Yang, Robert Deal, Josée S. Rousseau, Thomas Spies, Matthew G. BettsKeywordsSourceProceedings of the National Academy of Sciences. 101: 201813072-.Year2019
- The wood energy landscape is rapidly changing in southeast Alaska. One of the important decisions facing wood energy users is the best choice of wood fuel to use, with options often including wood chips, cordwood, and pellets. However, there are usually tradeoffs depending on the wood energy type selected: wood pellets must often be transported long distances, cordwood systems are relatively labor intensive, and chip-fired systems can often be very expensive. We consider the use of locally produced and engineered fuel chips as a fuel source for small thermal wood energy applications in...AuthorsDavid L. Nicholls, Robert Deering, Thomas R. MilesSourceGen. Tech. Rep. PNW-GTR-965. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 24 p.Year2019
- Most studies of the health benefits of the natural environment use coarse 2D exposure metrics based on the normalized difference vegetation index (NDVI). We compare the performance of these 2D NDVI metrics to finer-resolution 3D metrics derived from Light Detection and Ranging imagery (LiDAR). In logit models of small-for-gestational-age births, both NDVI and LiDAR metrics were associated with a reduced probability of an adverse birth outcome. However, models using LiDAR metrics had higher explanatory power than equivalent NDVI models, and LiDAR models also revealed that vegetation height...AuthorsGeoffrey Donovan, Demetrios Gatziolis, Kristen Jakstis, Saskia ComessKeywordsSourceHealth & Place. 57: 305-312.Year2019
- Background: Several small experimental studies and cross-sectional observational studies have shown that exposure to the natural environment might protect against attention-deficit hyperactivity disorder (ADHD) or moderate the symptoms of ADHD in children. We aimed to assess whether exposure to the natural environment protects against ADHD and whether this hypothesised protective effect varies across a child’s life course. Methods: We did a longitudinal study with data collected from all children born in New Zealand in 1998, excluding those without an address history, those who were not...AuthorsGeoffrey Donovan, Yvonne L Michael, Demetrios Gatziolis, Andrea' t Mannetje, Jeroen DouwesKeywordsSourceLancet Planet Health. 3: e226-e234.Year2019
- An increasing threat to U.S. waterways is the establishment and spread of invasive and injurious fishes. A species may be designated by the U.S. Fish and Wildlife Service (USFWS) as federally “injurious” under the Lacey Act (18 U.S.C. 42) either if that species causes harm (injury) without establishing and spreading (not invasive), or if that species causes harm after establishment and spread (invasive). Species designated as injurious are prohibited from being imported, which is a highly effective way of preventing invasions by nonnative species. We developed a decision-support, risk...AuthorsBruce G. Marcot, Michael H. Hoff, Craig D. Martin, Susan D. Jewell, Carrie E. GivensKeywordsSourceManagement of Biological Invasions. 10(2): 200-226.Year2019
- Western larch forests are iconic in the interior northwest, and here we document the preemptive steps that scientists and managers are taking to steward these forests into the future. Changing climate is forecast to have acute and chronic impacts on growth and disturbance in western larch forests. A group of scientists and managers in the northern Rocky Mountains have teamed up with the Adaptive Silviculture for Climate Change Network in an experiment to proactively manage forests for climate adaptation. The collaborative group developed a gradient of adaptation treatments (i.e., resistance...AuthorsElaine K. Sutherland, Terrie B. Jain, David K. Wright, Melissa Jenkins, Christopher Keyes, Linda M. Nagel, Justin S. CrotteauKeywordsSourceForest Science. 65(4): 528-536.Year2019
- Numerical simulations of laboratory-scale experiments, with no wind imposed, were performed for fuel bed slopes ranging from 0° to 45°. The implementation of a vertical symmetry plane (SP) placed, span-wise, along the middle of the computational domain, was assessed as an approach to reduce computational cost. The simulations were performed with Wildland-urban interface Fire Dynamics Simulator (WFDS). The experimental trends of the compared quantities were reproduced well by the simulations. Radiative heat transfer is the dominant mechanism of heating for slope angles between 0° and 22°,...AuthorsWilliam E. Mell, J. Torres-Arenas, Bret W. Butler, X. Sanchez-MonroyKeywordsSourceFire Safety Journal. 108: 102844.Year2019
- Documenting biodiversity and wildlife behavior is time‐consuming and potentially invasive. Remotely placed cameras often are used to increase sampling and minimize disturbance of focal animals. Such wildlife monitoring programs can entail numerous and lengthy videos requiring massive amounts of time to analyze their content. We evaluated the efficacy of a computer program, MotionMeerkat (http://benweinstein.weebly.com/motionmeerkat.html), for automated detection of motion in 21 continuous, 3‐hour‐long videos monitoring woodpecker (Picidae) nest cavities during 2016 in Washington, USA. The...AuthorsBruce G. Marcot, Teresa Lorenz, Philip Fischer, Ben G. Weinstein, Samuel CowellKeywordsSourceWildlife Society Bulletin. 43(4): 726-736.Year2019
- Insufficient winter chill accumulation can detrimentally impact agriculture. Understanding the changing risk of insufficient chill accumulation can guide orchard management and cultivar selection for long-lived perennial crops including peaches. This study quantifies the influence of modeled anthropogenic climate change on observed chill accumulation since 1981 and projected chill accumulation through the mid-21st century, with a focus on principal peach-growing regions in the southeastern United States, and commonly grown peach cultivars with low, moderate, and high chill accumulation...AuthorsJohn T. Abatzoglou, Lauren E. ParkerKeywordsSourceClimateYear2019