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- The invasive shrub Scotch broom (Cytisus scoparius(L.) Link) is a pervasive threat to regenerating Douglas-fir (Pseudotsuga menziesii(Mirb.) Franco var. menziesii) stands in the Pacific Northwest, USA. Field observations indicate that the susceptibility of areas to Scotch broom invasion and dominance can vary by site. We selected 10 sites throughout the western Pacific Northwest that spanned a gradient of soil textures and other factors to test the site-specific susceptibility of Douglas-fir to overtopping by Scotch broom. We expected to find that the ability of Scotch broom to dominate a...AuthorsDavid R. Carter, Robert A. Slesak, Timothy B. Harrington, Anthony W. D’AmatoKeywordsSourceCanadian Journal of Forest Research. 52(1): 38-50.Year2022
- The interaction of similar soil forming factors with different parent materials determines soil chemical weathering, influencing soil processes and properties. In the coastal temperate rainforests of southeast Alaska, Spodosols is the dominant soil order in well-drained parent materials regardless of the lithology. Yet, the role of lithology on chemical weathering, base cation depletion, and mineral transformation during pedogenesis remains elusive. Here, we established a lithosequence comprised of soils derived from tonalite, phyllite, slate, and metavolcanic rocks to test the hypothesis...AuthorsDiogo Spinola, Raquel Portes, Jennifer Fedenko, Rebecca Lybrand, Ashlee Dere, Frances Biles, Thomas Trainor, Mark E. Bowden, David V. D'AmoreKeywordsSourceGeoderma. 428(2): 116211.Year2022
- Predicting the edges of species distributions is fundamental for species conservation, ecosystem services, and management decisions. In North America, the location of the upstream limit of fish in forested streams receives special attention, because fish-bearing portions of streams have more protections during forest management activities than fishless portions. We present a novel model development and evaluation framework, wherein we compare 26 models to predict upper distribution limits of trout in streams. The models used machine learning, logistic regression, and a sophisticated nested...AuthorsBrooke Penaluna, Jonathan Burnett, Kelly Christiansen, Ivan Arismendi, Sherri Johnson, Kitty Griswold, Brett Holycross, Sonja KolstoeKeywordsSourceScientific Reports. 12(1): 20266.Year2022
- Leaf litter inputs can influence the structure and function of both terrestrial and adjacent aquatic ecosystems. Dioecy and herbivory are two factors that together have received little attention, yet have the potential to affect the quantity, quality, and timing of riparian litterfall, litter chemistry, and litter decomposition processes. Here, we explore litter chemistry differences for the dioecious Sitka willow (Salix sitchensis Sanson ex. Bong), which is establishing on primary successional habitats at Mount St. Helens (WA, USA) and is heavily infested with a stem-boring weevil...AuthorsJoy M. Ramstack Hobbs, Iris J. Garthwaite, Logan Lancaster, Jordan A. Moffett‐Dobbs, Kelly Johnson, Nichole Criss, Victoria McConathy, C. Andrew James, Alex Gipe, Shannon Claeson, Carri J. LeRoyKeywordsSourceEcology and Evolution. 12(12): e9626.Year2022
- We developed new measures of structural complexity using single point terrestrial laser scanning (TLS) point clouds. These metrics are depth, openness, and isovist. Depth is a three-dimensional, radial measure of the visible distance in all directions from plot center. Openness is the percent of scan pulses in the near-omnidirectional view without a return. Isovists are a measurement of the area visible from the scan location, a quantified measurement of the viewshed within the forest canopy. 243 scans were acquired in 27 forested stands in the Pacific Northwest region of the United...AuthorsJonathan L. Batchelor, Todd M. Wilson, Michael Olsen, William J. RippleKeywordsSourceRemote Sensing. 15(1): 145.Year2022
- Polycyclic aromatic hydrocarbons (PAHs) are air pollutants that are costly to measure using traditional air-quality monitoring methods. We used an epiphytic bio-indicator (moss genus: Orthotrichum) to cost-effectively evaluate atmospheric deposition of PAHs in Portland, Oregon in May 2013. However, it is unclear if measurements derived from these bioindicators are good proxies for human exposure. To address this question, we simultaneously, measured PAH-DNA adducts in blood samples of non-smokers residing close to the sites of moss measurements. We accounted for individual determinants of...AuthorsIgor Burstyn, Geoffrey Donovan, Yvonne L. Michael, Sarah JovanKeywordsSourcePLOS ONE. 17(12): e0279207.Year2022
- A new, dynamic reality is unfolding as climate change interacts with historical land management, causing changes in riverscape conditions that affect stream habitat and populations of native fishes. In Alaska, and elsewhere, land managers are facing new challenges as they seek to balance forest use with ecological resilience in rivers that support culturally and commercially important salmonids. In this context, data-driven forest management intended to maintain and restore landscapes relies on information that defines conditions over time. In this study, we analyzed 8 years of stream...AuthorsRebecca Flitcroft, Jay Munyon, Shannon Claeson, Adelaide C. Johnson, Michael Moore, Emil Tucker, Katherine Prussian, Sheila Jacobson, Heidi LombardKeywordsSourceGen. Tech. Rep. PNW-GTR-1009. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 77 p.Year2022
- Beaver-related restoration (BRR) has gained popularity as a means of improving stream ecosystems, but the effects are not fully understood. Studies of dissolved oxygen (DO) and water temperature, key water quality metrics for salmonids, have demonstrated improved conditions in some cases, but warming and decreased DO have been more commonly reported in meta-analyses. These results point to the contingencies that can influence outcomes from BRR. We examined water quality related to beaver ponds in a diverse coastal watershed (Umpqua River Basin, OR, USA). We monitored water temperature...AuthorsJohn R. Stevenson, Jason B. Dunham, Steve Wondzell, Jimmy TaylorSourceEcohydrology. 15(4): 206-222.Year2022
- The South Fork McKenzie River (SFMR) in western Oregon, USA hosts one of the largest Stage 0 stream restoration projects implemented to date. Stage 0 refers to a multichannel planform with strong hydrologic connectivity to the adjacent floodplain and surface–subsurface connectivity. Stage 0 restoration was implemented on a 900-m-long reach of the SFMR by re-grading the channel and floodplain using 65,000 m3 of sediment to raise the channel bed. Thousands of large logs were added and the ends of some logs were buried in the sediment to provide foundations for future log jams. Our primary...AuthorsSarah Hinshaw, Ellen Wohl, Jonathan Burnett, Steve WondzellKeywordsSourceEarth Surface Processes and Landforms. 47(8): 1937-1951.Year2022
- Research suggests that maternal exposure to natural environments (i.e., green and blue spaces) promotes healthy fetal growth. However, the available evidence is heterogeneous across regions, with very few studies on the effects of blue spaces. This study evaluated associations between maternal exposure to natural environments and birth outcomes in 11 birth cohorts across nine European countries. This study, part of the LifeCycle project, was based on a total sample size of 69,683 newborns with harmonised data. For each participant, we calculated seven indicators of residential exposure to...AuthorsMaria Torres Toda, Demetris Avraam, Timothy James Cadman, Serena Fossati, Montserrat de Castro, Audrius Dedele, Geoffrey Donovan, Ahmed Elhakeem, Marisa Estarlich, Amanda Fernandes, Romy Gonçalves, Regina Grazuleviciene, Jennifer R. Harris, Margreet Harskamp-van Ginkel, Barbara Heude, Jesús Ibarluzea, Carmen Iñiguez, Vincent WV Jaddoe, Deborah Lawlor, Aitana Lertxundi, Johanna Lepeule, Rosemary McEachan, Giovenale Moirano, Johanna LT Nader, Anne-Marie Nybo Andersen, Marie Pedersen, Costanza Pizzi, Theano Roumeliotaki, Susana Santos, Jordi Sunyer, Tiffany Yang, Marina Vafeiadi, Tanja GM Vrijkotte, Mark Nieuwenhuijsen, Martine Vrijheid, Maria Foraster, Payam DadvandSourceEnvironment International. 170: 107648.Year2022