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Science Quality and Integrity
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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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Evaluating water-quality trends in agricultural watersheds prioritized for management-practice implementation 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...
Authors
James S. Webber, Jeffrey G. Chanat, John W. Clune, Olivia Devereux, Natalie Celeste Hall, Robert D. Sabo, Qian Zhang
What the cliffs near America’s earliest settlements tell us about climate change 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...
Authors
Harry J. Dowsett, Marci M. Robinson
How, when and where current mass flows in Martian gullies are driven by CO2 sublimation How, when and where current mass flows in Martian gullies are driven by CO2 sublimation
Martian gullies resemble water-carved gullies on Earth, yet their present-day activity cannot be explained by water-driven processes. The sublimation of CO2 has been proposed as an alternative driver for sediment transport, but how this mechanism works remains unknown. Here we combine laboratory experiments of CO2-driven granular flows under Martian atmospheric pressure with 1D climate...
Authors
Lonneke Roelofs, Susan J. Conway, Tjalling de Haas, Colin M. Dundas, Stephen R. Lewis, Jim McElwaine, Kelly Pasquon, Jan Raack, Matt Sylvest, Manish Patel
Quantifying spatiotemporal variation of nearshore forage fish schools with aerial surveys in Prince William Sound, Alaska Quantifying spatiotemporal variation of nearshore forage fish schools with aerial surveys in Prince William Sound, Alaska
Objective Changes 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...
Authors
Daniel Stephen Donnelly, Mayumi L. Arimitsu, Scott Pegau, John F. Piatt
Arsenic and other geogenic contaminants in global groundwater Arsenic and other geogenic contaminants in global groundwater
Geogenic groundwater contaminants (GGCs) affect drinking-water availability and safety, with up to 60% of groundwater sources in some regions contaminated by more than recommended concentrations. As a result, an estimated 300–500 million people are at risk of severe health impacts and premature mortality. In this Review, we discuss the sources, occurrences and cycling of arsenic...
Authors
Abhijit Mukherjee, Poulomee Coomar, Soumyajit Sarkar, Karen H. Johannesson, Alan Fryar, Madeline Schreiber, Kazi M. Ahmed, Mohd. A. Alam, Prosun Bhattacharya, Jochen Bundschuh, William Burgess, Madhumita Chakraborty, Rachel Coyte, Abida Farooqi, Huaming Guo, Julian Ijumulana, Gh Jeelani, Debapriya Mondal, D. Kirk Nordstrom, Joel Podgorski, David Polya, Bridget R. Scanlon, Mohd. Shamsudduha, Joseline Tapia, Avner Vengosh
Influence of irrigation water and soil on annual mercury dynamics in Sacramento Valley rice fields Influence of irrigation water and soil on annual mercury dynamics in Sacramento Valley rice fields
Methylmercury (MeHg) is a human and environmental toxin produced in flooded soils. Little is known about MeHg in rice (Oryza Sativa L.) fields in Sacramento Valley, California. The objectives of this study were to quantify mercury fractions in irrigation water and within rice fields and to determine their mercury pools in surface water, soil, and grain. Soil, grain, and surface water...
Authors
Luke A. Salvato, Mark C. Marvin-DiPasquale, Jacob Fleck, Stephen A. McCord, Bruce A. Linquist
Cathodoluminescence differentiates sedimentary organic matter types 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...
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 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...
Authors
Cynthia Dusel-Bacon, John N. Aleinikoff, Suzanne Paradise, John F. Slack
Chemistry, growth, and fate of the unique, short-lived (2019–2020) water lake at the summit of Kīlauea Volcano, Hawaii Chemistry, growth, and fate of the unique, short-lived (2019–2020) water lake at the summit of Kīlauea Volcano, Hawaii
Less than a year after the 2018 Kīlauea caldera collapse and eruption, water appeared in newly deepened Halemaʻumaʻu crater. The lake—unprecedented in the written record—grew to a depth of ∼50 m before lava from the December 2020 eruption boiled it away. Surface water heightened concerns of potential phreatic or phreatomagmatic explosions but also offered a new means of possibly...
Authors
Patricia A. Nadeau, Shaul Hurwitz, Sara Peek, Allan Lerner, Edward F. Younger, Matthew R. Patrick, David Damby, R. Blaine McCleskey, Peter J. Kelly
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 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 +...
Authors
Zikri Arslan, Heather A. Lowers
Deep learning for water quality Deep learning for water quality
Understanding and predicting the quality of inland waters are challenging, particularly in the context of intensifying climate extremes expected in the future. These challenges arise partly due to complex processes that regulate water quality, and arduous and expensive data collection that exacerbate the issue of data scarcity. Traditional process-based and statistical models often fall...
Authors
Wei Zhi, Alison P. Appling, Heather E. Golden, Joel Podgorski, Li Li
Using global remote camera data of a solitary species complex to evaluate the drivers of group formation Using global remote camera data of a solitary species complex to evaluate the drivers of group formation
The social system of animals involves a complex interplay between physiology, natural history, and the environment. Long relied upon discrete categorizations of “social” and “solitary” inhibit our capacity to understand species and their interactions with the world around them. Here, we use a globally distributed camera trapping dataset to test the drivers of aggregating into groups in a...
Authors
Joshua P. Twining, Chris Sutherland, Andrzej Zalewski, Michael V. Cove, Johnny Birks, Oliver R. Wearn, Jessica Haysom, Anna Wereszczuk, Emiliano Manzo, Paola Bartolommei, Alessio Mortelliti, Bryn Evans, Brian D. Gerber, Thomas J. McGreevy, Laken S. Ganoe, Juliana Masseloux, Amy E. Mayer, Izabela Wierzbowska, Jan Loch, Jocelyn Akins, Donovan Drummey, William McShea, Stephanie Manke, Lain Pardo, Andy Boyce, Sheng Li, Roslina Binti Ragai, Ronglarp Sukmasuang, Alvaro Jose Villafane Trujillo, Carlos Lopez-Gonzalez, Nalleli Elvira Lara-Diaz, Olivia Cosby, Cristian N. Waggershauser, Jack Bamber, Frances Stewart, Jason Fisher, Angela K. Fuller, Kelly Perkins, Roger A. Powell