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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
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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Yosemite toad (Anaxyrus canorus) transcriptome reveals interplay between speciation genes and adaptive introgression
Genomes are heterogeneous during the early stages of speciation, with small ‘islands’ of DNA appearing to reflect strong adaptive differences, surrounded by vast seas of relative homogeneity. As species diverge, secondary contact zones between them can act as an interface and selectively filter through advantageous alleles of hybrid origin. Such introgression is another important adaptive process,
Authors
Paul A. Maier, A. G. Vandergast, Andrew J. Bohonak
Temporal variability and sources of PFAS in the Rio Grande, New Mexico through an arid urban area using multiple tracers and high-frequency sampling
Per- and polyfluoroalkyl substances (PFAS) are ubiquitous in the environment but sources are not well defined for temporal and spatial aspects within an urban environment, and especially for an arid urban environment subject to seasonal short term high-intensity precipitation events. A focused diel sampling was conducted in the summer of 2021 to assess the temporal and spatial variability of PFAS
Authors
Kimberly R. Beisner, Rebecca E. Travis, David Alvarez, Larry Barber, Jacob Fleck, Jeramy Jasmann
Implications for the resilience of modern coastal systems derived from mesoscale barrier dynamics at Fire Island, New York
Understanding the response of coastal barriers to future changes in rates of sea level rise, sediment availability, and storm intensity/frequency is essential for coastal planning, including socioeconomic and ecological management. Identifying drivers of past changes in barrier morphology, as well as barrier sensitivity to these forces, is necessary to accomplish this. Using remote sensing, field,
Authors
Daniel J. Ciarletta, Jennifer L. Miselis, Julie Bernier, Arnell S. Forde
Climatic variability as a principal driver of primary production in the southernmost subalpine Rocky Mountain lake
Mountain lakes are sensitive indicators of anthropogenically driven global change, with lake sediment records documenting increased primary production during the twentieth century. Atmospheric nutrient deposition and warming have been attributed to changes in other Western mountain lakes, however, the intensity of these drivers varies. We analyzed a sediment core representing a 270-year record fro
Authors
Anna Shampain, Jill Baron, Peter R. Leavitt, Sarah Spaulding
Modeled flooding by tsunamis and a storm versus observed extent of coral erratics on Anegada, British Virgin Islands— Further evidence for a great Caribbean earthquake six centuries ago
Models of near-field tsunamis and an extreme hurricane provide further evidence for a great precolonial earthquake along the Puerto Rico Trench. The models are benchmarked to brain-coral boulders and cobbles on Anegada, 125 km south of the trench. The models are screened by their success in flooding the mapped sites of these erratics, which were emplaced some six centuries ago. Among 25 tsunami sc
Authors
Yong Wei, Uri S. ten Brink, Brian F. Atwater
Spatial extent drives patterns of relative climate change sensitivity for freshwater fishes of the United States
Assessing the sensitivity of freshwater species to climate change is an essential component of prioritizing conservation efforts for threatened freshwater ecosystems and organisms. Sensitivity to climate change can be systematically evaluated for multiple species using geographic attributes such as range size and climate niche breadth, and using species traits associated with climate change sensit
Authors
Samuel C. Silknetter, Abigail Benson, Jennifer A. Smith, Meryl C. Mims
Evaluating water-quality trends in agricultural watersheds prioritized for management-practice implementation
Many agricultural watersheds rely on the voluntary use of management practices (MPs) to reduce nonpoint source nutrient and sediment loads; however, the water-quality effects of MPs are uncertain. We interpreted water-quality responses from as early as 1985 through 2020 in three agricultural Chesapeake Bay watersheds that were prioritized for MP implementation, namely, the Smith Creek (Virginia),
Authors
James S. Webber, Jeffrey G. Chanat, John Clune, Olivia H. Devereux, Natalie Celeste Hall, Robert D. Sabo, Qian Zhang
What the cliffs near America’s earliest settlements tell us about climate change
Climate change is a big problem for natural habitats, people, and the systems that support society, including roads, water supply, electrical grids, and phone and internet connections. It’s an important theme in politics, economics, and culture. Scientists make computer models to show what the climate might be like in the future, and it looks very different from what we are used to. Scientists can
Authors
Harry J. Dowsett, Marci M. Robinson
Quantifying spatiotemporal variation of nearshore forage fish schools with aerial surveys in Prince William Sound, Alaska
ObjectiveChanges in abundance and distribution of schooling forage fish, such as the Pacific Sand Lance Ammodytes hexapterus and Pacific Herring Clupea pallasii, can be difficult to document using traditional boat-based methods, especially in the shallow, nearshore habitats frequented by these species. In contrast, nearshore fish schools are easily observed and quantified from aircraft when light
Authors
Daniel Stephen Donnelly, Mayumi L. Arimitsu, Scott Pegau, John F. Piatt
Cathodoluminescence differentiates sedimentary organic matter types
High-resolution scanning electron microscopy (SEM) visualization of sedimentary organic matter is widely utilized in the geosciences for evaluating microscale rock properties relevant to depositional environment, diagenesis, and the processes of fluid generation, transport, and storage. However, despite thousands of studies which have incorporated SEM methods, the inability of SEM to differentiate
Authors
Paul C. Hackley, Ryan J. McAleer, Aaron M. Jubb, Brett J. Valentine, Justin E. Birdwell
Sulphide petrology and ore genesis of the stratabound Sheep Creek sediment-hosted Zn–Pb–Ag–Sn prospect, and U–Pb zircon constraints on the timing of magmatism in the northern Alaska Range
The Sheep Creek prospect is a stratabound Zn–Pb–Ag–Sn massive sulfide occurrence in the Bonnifield mining district, northern Alaska Range. The prospect is within a quartz–sericite–graphite–chlorite schist unit associated with Devonian carbonaceous and siliceous metasedimentary rocks. Volcanogenic massive sulfide (VMS) deposits in the district are hosted in felsic metavolcanic rocks (362 ± 2 Ma) as
Authors
Cynthia Dusel-Bacon, John N. Aleinikoff, Suzanne Paradise, John F. Slack
Trace silicon determination in biological samples by inductively coupled plasma mass spectrometry (ICP-MS): Insight into volatility of silicon species in hydrofluoric acid digests for optimal sample preparation and introduction to ICP-MS
A method for the determination of trace levels of silicon from biological materials by inductively coupled plasma mass spectrometry (ICP-MS) has been developed. The volatility of water-soluble silicon species, hexafluorosilicic acid (H2SiF6), and sodium metasilicate (Na2SiO3) was investigated by evaporating respective solutions (50 µg/mL silicon) in nitric acid (HNO3), nitric acid + hydrochloric a
Authors
Zikri Arslan, Heather A. Lowers