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Page 837, results 20901 - 20925

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Factors influencing fine sediment on stream beds in the Midwestern United States
Christopher P. Konrad, Allen C. Gellis
2018, Journal of Environmental Quality (47) 1214-1222
Fine sediment (particles <2 mm in diameter) in stream beds has wide-ranging effects on hydraulics, geomorphology, and ecology and is a primary focus for stream quality management in many regions. We identify reach- and basin-scale factors associated with fine sediment in the beds of 83 stream reaches in the Midwestern...
Isolation by distance versus landscape resistance: Understanding dominant patterns of genetic structure in Northern Spotted Owls (Strix occidentalis caurina)
Mark P. Miller, Raymond J. Davis, Eric D. Forsman, Thomas D. Mullins, Susan M. Haig
2018, PLoS ONE (13) 1-14
Landscape genetics investigations examine how the availability and configuration of habitat influence genetic structure of plants and animals. We used landscape genetics to evaluate the role that forest connectivity plays in determining genetic structure of the federally-threatened Northern Spotted Owl (Strix occidentalis caurina) using genotypes of 339 Northern Spotted Owls...
Volcanic eruptions and threats to respiratory health
W. Graham Carlos, Jane E. Gross, Shazia Jamil, Charles S. Dela Cruz, David Damby, Elizabeth K. Tam
2018, American Journal of Respiratory and Critical Care Medicine (197) P21-P22
In early May 2018, Kīlauea volcano became increasingly active, posing an increase in threat to respiratory health. The emission of gases such as sulfur dioxide from Kīlauea produces large amounts of respirable acid particles as the gases react with water vapor and sunlight, resulting in a visible haze called “vog”....
Riparian defoliation by the invasive green alder sawfly influences terrestrial prey subsidies to salmon streams
David A. Roon, Mark S. Wipfli, James J. Kruse
2018, Ecology of Freshwater Fish (27) 963-975
Invasive species in riparian forests are unique as their effects can transcend ecosystem boundaries via stream‐riparian linkages. The green alder sawfly (Monsoma pulveratum) is an invasive wasp whose larvae are defoliating riparian thin‐leaf alder (Alnus tenuifolia) stands across southcentral Alaska. To test the hypothesis that riparian defoliation by this invasive...
Timescales of magmatic differentiation from alkali basalt to trachyte within the Harrat Rahat volcanic field, Kingdom of Saudi Arabia
Mark E. Stelten, Drew T. Downs, Hannah R. Dietterich, Gail A. Mahood, Andrew T. Calvert, Thomas W. Sisson, Hani M. Zahran, Jamal Shawali
2018, Contributions to Mineralogy and Petrology (173) 1-17
A fundamental goal of igneous petrology is to quantify the duration of time required to produce evolved magmas following influx of basalt into the crust. However, in many cases, complex field relations and/or the presence of a long-lived magmatic system make it difficult to assess how basaltic inputs relate to...
Improving understanding of soil organic matter dynamics by triangulating theories, measurements, and models
Joseph C. Blankinship, Susan E. Crow, Asmeret Asefaw Berhe, Jennifer L. Druhan, Katherine A. Heckman, Marco Keiluweit, Corey R. Lawrence, Erika Marin-Spiotta, Alain F. Plante, Craig Rasmussen, Christina Schadel, Joshua P. Schmiel, Carlos A. Sierra, Aaron Thomson, Rota Wagai, William R. Weider
2018, Biogeochemistry (140) 1-13
Soil organic matter (SOM) turnover increasingly is conceptualized as a tension between accessibility to microorganisms and protection from decomposition via physical and chemical association with minerals in emerging soil biogeochemical theory. Yet, these components are missing from the original mathematical models of belowground carbon dynamics and remain underrepresented in more...
Geologic map of the Hayfield quadrangle, Frederick County, Virginia
Daniel H. Doctor, Ronald A. Parker
2018, Scientific Investigations Map 3407
The Hayfield 7.5-minute quadrangle is located within the Valley and Ridge physiographic province of northern Virginia. The quadrangle includes the topographical lowland area of the northern Great Valley to the southeast, the narrow ridge of Little North Mountain along the western edge of the Great Valley, and the broad region...
Metal reactivity in laboratory burned wood from a watershed affected by wildfires
Asifur Rahman, Eliane El Hayek, Johanna M. Blake, Rebecca J. Bixby, Abdul-Mehdi Ali, Michael Spilde, Amanda A. Otieno, Keely Miltenberger, Cyrena Ridgeway, Kateryna Artyushkova, Viorel Atudorei, Jose M. Ceratto
2018, Environmental Science & Technology (52) 8115-8123
We investigated interfacial processes affecting metal mobility by wood ash under laboratory-controlled conditions using aqueous chemistry, microscopy, and spectroscopy. The Valles Caldera National Preserve in New Mexico experiences catastrophic wildfires of devastating effects. Wood samples of Ponderosa Pine, Colorado Blue Spruce, and Quaking Aspen collected from this site were exposed...
Evidence for exposure to selenium by breeding interior snowy plovers (Charadrius nivosus) in saline systems of the Southern Great Plains
H.M. Ashbaugh, Warren C. Conway, David A. Haukos, D. P. Collins, C. E. Comer, A. D. French
2018, Ecotoxicology (27) 703-718
Interior snowy plover (Charadrius nivosus) population declines and deteriorating conditions throughout the Southern Great Plains (SGP) of Texas, New Mexico, and Oklahoma may be linked to environmental contaminants. Concentrations of V, As, Cd, Pb, and Se were quantified in breeding snowy plover blood, feathers (5th primary; P5), and...
A critical time for mercury science to inform global policy
Celia Y. Chen, Charles T. Driscoll, Collin A. Eagles-Smith, Chris S. Eckley, David A. Gay, Heileen Hsu-Kim, S. E. Keane, Jane L. Kirk, Robert Mason, Daniel Obrist, Henrik Selin, Noelle Selin, Marcella R. Thompson
2018, Environmental Science & Technology (52) 9556-9561
Mercury is a global pollutant released into the biosphere by varied human activities including coal combustion, mining, artisanal gold mining, cement production, and chemical production. Once released to air, land and water, the addition of carbon atoms to mercury by bacteria...
A new high-resolution map of world mountains and an online tool for visualizing and comparing characterizations of global mountain distributions
Roger Sayre, Charlie Frye, Deniz Karagulle, Jurg Krauer, Sean Breyer, Peter Aniello, Dawn J. Wright, Davnah Payne, Carolina Adler, Harumi Warner, D. Paco Van Sistine, Jill Janene Cress
2018, Mountain Research and Development (38) 240-249
Answers to the seemingly straightforward questions “what is a mountain?” and “where are the mountains of the world?” are in fact quite complex, and there have been few attempts to map the mountains of the earth in a consistent and rigorous fashion. However, knowing exactly where mountain ecosystems are distributed...
Monitoring mountains in a changing world: New horizons for the Global Network for Observations and Information on Mountain Environments (GEO-GNOME)
Carolina Adler, Elisa Palazzi, Aino Kulonen, Jorg Balsiger, Guido Colangeli, Douglas Cripe, Nathan Forsythe, Grace Goss-Durant, Yaniss Guigoz, Jurg Krauer, Davnah Payne, Nicholas Pepin, Manuel Peralvo, Jose Romero, Roger Sayre, Maria Shahgedanova, Rolf Weingartner, Marc Zebisch
2018, Mountain Research and Development (38) 265-269
Mountains are globally distributed environments that provide significant societal benefits, a function that is increasingly compromised by climatic change, environmental stress, political and socioeconomic transformations, and unsustainable use of natural resources. Gaps in our understanding of these processes and their interactions limit our capacity to inform decisions, where both generalities...
Landscape genetics identifies streams and drainage infrastructure as dispersal corridors for an endangered wetland bird
Charles B. van Rees, J. Michael Reed, Robert E. Wilson, Jared G. Underwood, Sarah A. Sonsthagen
2018, Ecology and Evolution (8) 8328-8343
Anthropogenic alterations to landscape structure and composition can have significant impacts on biodiversity, potentially leading to species extinctions. Population‐level impacts of landscape change are mediated by animal behaviors, in particular dispersal behavior. Little is known about the dispersal habits of rails (Rallidae) due to their cryptic behavior and tendency to...
Tritium deposition in precipitation in the United States, 1953–2012
Robert L. Michel, Bryant C. Jurgens, Megan B. Young
2018, Scientific Investigations Report 2018-5086
Tritium is a radioactive isotope of hydrogen (half-life is equal to 12.32 years). Since it is part of the water molecule, tritium can be used to track and date groundwater and surface water when the history of tritium in precipitation and recharge is known. To facilitate that effort, tritium concentrations...
Review and development of ASABE Engineering Practice 621: “Guidelines for calibrating, validating, and evaluating hydrologic and water quality models”
R. Daren Harmel, Claire Baffaut, Kyle R. Douglas-Mankin
2018, Transactions of the ASABE (61) 1393-1401
In 2010, the Natural Resources and Environmental Systems Hydrology Committee (NRES-21) of ASABE initiated a long-term process to develop guidelines to improve modeling practice through better understanding of the calibration, validation, and evaluation process across applications and more effective interpretation and communication of model performance. This effort generated a compilation...
Limits to ponderosa pine regeneration following large high-severity forest fires in the United States Southwest
Collin Haffey, Thomas D. Sisk, Craig D. Allen, Andrea E. Thode, Ellis Q. Margolis
2018, Fire Ecology (14) 143-163
High-severity fires in dry conifer forests of the United States Southwest have created large (>1000 ha) treeless areas that are unprecedented in the regional historical record. These fires have reset extensive portions of Southwestern ponderosa pine (Pinus ponderosa Lawson & C. Lawson var. scopulorum Engelm.) forest landscapes. At least two...
The influence of nutrients from carcasses of sea lamprey (Petromyzon marinus) on larval growth and spawner abundance
Daniel M. Weaver, Stephen M. Coghlan Jr., Joseph D. Zydlewski
2018, Fishery Bulletin (116) 142-152
Migrations of anadromous sea lamprey (Petromyzon marinus) from marine ecosystems serve as vectors of nutrients into freshwater food webs. Larval sea lamprey reside in streams for 6–8 years as deposit feeders before metamorphosing into juveniles and migrating to the ocean. Previous work has shown that carcass nutrients, which result from...
Patterns of longer-term climate change effects on CO2 efflux from biocrusted soils differ from those observed in the short term
Anthony Darrouzet-Nardi, Sasha C. Reed, Edmund E. Grote, Jayne Belnap
2018, Biogeosciences (15) 4561-4573
Biological soil crusts (biocrusts) are predicted to be sensitive to the increased temperature and altered precipitation associated with climate change. We assessed the effects of these factors on soil carbon dioxide (CO2) balance in biocrusted soils using a sequence of manipulations over a 9-year period. We warmed biocrusted soils by...
Drivers and mechanisms of tree mortality in moist tropical forests
Nate G. McDowell, Craig D. Allen, Kristina Anderson‐Teixeira, Paulo M. Brando, Roel Brienen, Jeff Chambers, Brad Christoffersen, Stuart J. Davies, Chris Doughty, Alvaro Duque, Fernando Espirito-Santo, Rosie A. Fisher, Clarissa G. Fontes, David Galbraith, Devin Goodsman, Charlotte Grossiord, Henrik Hartmann, Jennifer Holm, Daniel J. Johnson, Abd. Rahman Kassim, Michael Keller, Charles Koven, Lara Kueppers, Tomo’omi Kumagai, Yadvinder Malhi, Sean M. McMahon, Maurizio Mencuccini, Patrick Meir, Paul R. Moorcroft, Helene C. Muller-Landau, Oliver L. Phillips, Thomas M. Powell, Carlos A. Sierra, John Sperry, Jeff Warren, Chonggang Xu, Xiangtao Xu
2018, New Phytologist (219) 851-869
Tree mortality rates appear to be increasing in moist tropical forests (MTFs) with significant carbon cycle consequences. Here, we review the state of knowledge regarding MTF tree mortality, create a conceptual framework with testable hypotheses regarding the drivers, mechanisms and interactions that may underlie increasing MTF mortality rates, and identify...
Influencia de factores ambientales y biométricos en la capacidad de nado del barbo ibérico (Luciobarbus bocagei Steindachner, 1864), un ciprínido potamódromo endémico de la Península Ibérica
Jorge Ruiz-Legazpi, F.J. Sanz-Ronda, F.J. Bravo-Cordoba, J.F. Fuentes-Perez, Theodore R. Castro-Santos
2018, Limnetica (37) 251-265
El presente trabajo analiza la capacidad voluntaria de nado del barbo ibérico (Luciobarbus bocagei Steindachner, 1864) en un canal abierto durante su época de migración, relacionándola con factores ambientales y biométricos. La temperatura del agua, la velocidad de flujo y la longitud del pez fueron los factores de mayor importancia...
Climate change and future wildfire in the western USA: An ecological approach to nonstationarity
Jeremy S. Littell, Donald McKenzie, Ho Yi Wan, Samuel A. Cushman
2018, Earth's Future (6) 1097-1111
We developed ecologically based climate‐fire projections for the western United States. Using a finer ecological classification and fire‐relevant climate predictors, we created statistical models linking climate and wildfire area burned for ecosections, which are geographic delineations based on biophysical variables. The results indicate a gradient from purely fuel‐limited (antecedent positive...
Applying recreation ecology science to sustainably manage camping impacts: A classification of camping management strategies
Jeffrey L. Marion, Johanna Arredondo, Jeremy Wimpey, Fletcher Meadema
2018, International Journal of Wilderness (24) 1-12
Wilderness and other protected natural areas such as national forests, parks, and refuges are managed to provide high-quality recreational opportunities while preserving natural resource conditions. In managing recreation visitation, land managers could allow visitors to create their own infrastructure of trails and campsites, or they could choose to apply an...
Assessing and communicating the impacts of climate change on the Southern California coast
Li H. Erikson, Patrick L. Barnard, Andrea C. O'Neill, Patrick Limber, Sean Vitousek, Juliette Finzi Hart, Maya Hayden, Jeanne M. Jones, Nathan J. Wood, Michael Fitzgibbon, Amy C. Foxgrover, Jessica Lovering
2018, Report
Over the course of this and the next century, the combination of rising sea levels, severe storms, and coastal erosion will threaten the sustainability of coastal communities, development, and ecosystems as we currently know them. To clearly identify coastal vulnerabilities and develop appropriate adaptation strategies for projected increased levels of...
National Park Service and the USA National Phenology Network
Jake Weltzin, Theresa M. Crimmins, Erin E. Posthumus, Alyssa Rosemartin
2018, Report
Understanding the seasonal cycles of plants and animals, how they are changing, and how they can inform management, operations, and interpretation is critical to the mission of the National Park Service (NPS): to preserve unimpaired the natural and cultural resources and values of the National Park System for the enjoyment, education, and inspiration of this...
Gas emissions, tars, and secondary minerals at the Ruth Mullins and Tiptop coal mine fires
Jennifer M. K. O’Keefe, Erika R. Neace, Maxwell L. Hammond III, James C. Hower, Mark A. Engle, Joseph A. East, Nicholas J. Geboy, Ricardo A. Olea, Kevin R. Henke, Gregory C. Copley, Edward W. Lemley, Rachel S. Hatch Nally, Antonia E. Hansen, Allison R. Richardson, Anne B. Satterwhite, Glenn B. Stracher, Larry F. Radke, Charles Smeltzer, Christopher Romanek, Donald R. Blake, Paul A. Schroeder, Stephen D. Emsbo-Mattingly, Scott A. Stout
2018, International Journal of Coal Geology (195) 304-316
Both the Tiptop and Ruth Mullins coal fires, Kentucky, were reinvestigated in 2009 and 2010. The Tiptop fire was not as active in 2009 and may have been on the path to burning out at the time of the 2009 visit. The Ruth Mullins coal mine fire, Perry County, Kentucky, has been the subject of several...