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Browse more than 65,000 articles authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
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Hydrogen isotope behavior during rhyolite glass hydration under hydrothermal conditions Hydrogen isotope behavior during rhyolite glass hydration under hydrothermal conditions
The diffusion of molecular water (H2Om) from the environment into volcanic glass can hydrate the glass up to several wt% at low temperature over long timescales. During this process, the water imprints its hydrogen isotope composition (δDH2O) to the glass (δDgl) offset by a glass-H2O fractionation factor (ΔDgl-H2O = δDgl – δDH2O) which is approximately −33‰ at Earth surface temperatures...
Authors
Michael R. Hudak, Ilya N. Bindeman, James M. Watkins, Jacob B. Lowenstern
Identifying turbulence features hindering swimming capabilities of grass carp larvae (Ctenopharyngodon idella) through submerged vegetation Identifying turbulence features hindering swimming capabilities of grass carp larvae (Ctenopharyngodon idella) through submerged vegetation
Aquatic vegetation can provide habitat and refuge for a variety of species in streams. However, the flow features generated by submerged patches of vegetation can also pose a challenge for fish larvae. We conducted a series of experiments with live grass carp larvae (starting ∼50 h post hatch) in a laboratory racetrack flume, using a submerged array of rigid cylinders to mimic vegetation...
Authors
Rafael O. Tinoco, Andres F. Prada, Amy E. George, Benjamin H. Stahlschmidt, P. Ryan Jackson, Duane Chapman
Inferring hatchery effects using spawner-recruit data: Comment on Courter et al. (2022) Inferring hatchery effects using spawner-recruit data: Comment on Courter et al. (2022)
No abstract available.
Authors
Matthew Richard Falcy
Long-term annual aerial surveys of submersed aquatic vegetation (SAV) support science, management, and restoration Long-term annual aerial surveys of submersed aquatic vegetation (SAV) support science, management, and restoration
Aerial surveys of coastal habitats can uniquely inform the science and management of shallow, coastal zones, and when repeated annually, they reveal changes that are otherwise difficult to assess from ground-based surveys. This paper reviews the utility of a long-term (1984-present) annual aerial monitoring program for submersed aquatic vegetation (SAV) in Chesapeake Bay, its tidal...
Authors
Robert J. Orth, William C. Dennison, Cassie Gurbisz, Michael P. Hannam, Jennifer L. Keisman, J. Brooke Landry, Jonathan S. Lefcheck, Kenneth A. Moore, Rebecca Murphy, Christopher J. Patrick, Jeremy Testa, Donald E. Weller, David J. Wilcox, Richard A. Batiuk
Mapping the extent and methods of small-scale emerald mining in the Panjshir Valley, Afghanistan Mapping the extent and methods of small-scale emerald mining in the Panjshir Valley, Afghanistan
Emerald mining in the Panjshir Valley, Afghanistan, has occurred for thousands of years, yet few records exist documenting the detailed spatial extent, techniques, or productivity of small-scale miners. This study proposes new methods to map and monitor the extent and changes in small-scale mining in remote and inaccessible terrain by integrating multispectral remote sensing analysis...
Authors
Jessica D. DeWitt, Peter G. Chirico, Kelsey L. O’Pry, Sarah E. Bergstresser
New indicators of ecological resilience and invasion resistance to support prioritization and management in the sagebrush biome, United States New indicators of ecological resilience and invasion resistance to support prioritization and management in the sagebrush biome, United States
Ecosystem transformations to altered or novel ecological states are accelerating across the globe. Indicators of ecological resilience to disturbance and resistance to invasion can aid in assessing risks and prioritizing areas for conservation and restoration. The sagebrush biome encompasses parts of 11 western states and is experiencing rapid transformations due to human population...
Authors
Jeanne C. Chambers, Jessi L. Brown, John B. Bradford, David I. Board, Steven B. Campbell, Karen J. Clause, Brice Hanberry, Daniel Rodolphe Schlaepfer, Alexandra K. Urza
Novel circoviruses detected in feces of Sonoran felids Novel circoviruses detected in feces of Sonoran felids
Sonoran felids are threatened by drought and habitat fragmentation. Vector range expansion and anthropogenic factors such as habitat encroachment and climate change are altering viral evolutionary dynamics and exposure. However, little is known about the diversity of viruses present in these populations. Small felid populations with lower genetic diversity are likely to be most...
Authors
Natalie Payne, Simona Kraberger, Rafaela S. Fontenele, Kara Schmidlin, Melissa H. Bergeman, Ivonne Cassaigne, Melanie Culver, Arvind Varsani, Koenraad Van Doorslaer
Salinification of coastal wetlands and freshwater management to support resilience Salinification of coastal wetlands and freshwater management to support resilience
Climates are rapidly changing in wetland ecosystems around the world and historical land-use change is not always given enough consideration in climate adaptation discussions. Historical changes to hydrology and other key environments can exacerbate vegetation stress; e.g., recent drought and flood episodes are likely more extreme because of climate change. The contributions of global...
Authors
Beth A. Middleton, Jere Boudell
Sea otters in a California estuary: Detecting temporal and spatial dynamics with volunteer monitoring Sea otters in a California estuary: Detecting temporal and spatial dynamics with volunteer monitoring
Volunteer monitoring can support conservation of imperiled wildlife, by providing higher resolution data in space and time than those available from professional scientists. However, concerns have been raised that data collected by amateurs are inaccurate or inconsistent and thus do not allow for robust detection of spatial or temporal trends. We evaluated the rigor and value of...
Authors
Ron Eby, Susan Rosso, John Copriviza, Robert Scoles, Yohn Gideon, Joseph Mancino, Karl A. Mayer, Julie L. Yee, Kerstin Wasson
Spatial and temporal variability in lake trout diets in Lake Ontario as revealed by stomach contents and stable isotopes Spatial and temporal variability in lake trout diets in Lake Ontario as revealed by stomach contents and stable isotopes
Lake trout (Salvelinus namaycush) are an ecologically and economically important piscivore with reported differences in diet and feeding behaviour throughout its range. Eleven stomach content and stable isotope-based metrics were used to describe diets of 349 lake trout between two years (2013 and 2018) and among geographic zones (west, central, east, Kingston basin) in Lake Ontario...
Authors
Brent M. Nawrocki, Brent W. Metcalfe, Jeremy P. Holden, Brian F. Lantry, Timothy B. Johnson
The source, fate, and transport of arsenic in the Yellowstone hydrothermal system - An overview The source, fate, and transport of arsenic in the Yellowstone hydrothermal system - An overview
The Yellowstone Plateau Volcanic Field (YPVF) contains >10,000 thermal features including hot springs, pools, geysers, mud pots, and fumaroles with diverse chemical compositions. Arsenic (As) concentrations in YPVF thermal waters typically range from 0.005 to 4 mg/L, but an As concentration of 17 mg/L has been reported. Arsenic data from thermal springs, outflow drainages, rivers, and...
Authors
R. Blaine McCleskey, D. Kirk Nordstrom, Shaul Hurwitz, Daniel R. Colman, David A. Roth, Madeline Oxner Johnson, Eric S. Boyd
Tungsten skarn potential of the Yukon-Tanana Upland, eastern Alaska, USA—A mineral resource assessment Tungsten skarn potential of the Yukon-Tanana Upland, eastern Alaska, USA—A mineral resource assessment
Tungsten (W) is used in a variety of industrial and technological applications and has been identified as a critical mineral for the United States, India, the European Union, and other countries. These countries rely on W imports mostly from China, which leaves them vulnerable to supply disruption. Consequently, the U.S. government has a current initiative to understand domestic resource...
Authors
George N.D. Case, Garth E. Graham, Erin E. Marsh, Ryan D. Taylor, Carlin J. Green, Philip J. Brown, Keith A. Labay