Articles
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
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.
Filter Total Items: 77848
Post-landing major element quantification using SuperCam laser induced breakdown spectroscopy Post-landing major element quantification using SuperCam laser induced breakdown spectroscopy
The SuperCam instrument on the Perseverance Mars 2020 rover uses a pulsed 1064 nm laser to ablate targets at a distance and conduct laser induced breakdown spectroscopy (LIBS) by analyzing the light from the resulting plasma. SuperCam LIBS spectra are preprocessed to remove ambient light, noise, and the continuum signal present in LIBS observations. Prior to quantification, spectra are...
Authors
Ryan B. Anderson, Olivier Forni, Agnes Cousin, Roger C. Wiens, Samuel M. Clegg, Jens Frydenvang, Travis S.J. Gabriel, Ann M. Ollila, Susanne Schröder, Olivier Beyssac, Erin Gibbons, David Vogt, Elise Clave, Jose-Antonio Manrique, Carey Legett, Paolo Pilleri, Raymond Newell, Joseph Sarrao, Sylvestre Maurice, Gorka Arana, Karim Benzerara, Pernelle Bernardi, Sylvain Bernard, Bruno Bousquet, Adrian J. Brown, Cesar Alvarez-Llamas, Baptiste Chide, Edward A. Cloutis, Jade Comellas, Stephanie Connell, Erwin Dehouck, Dorothea Delapp, Ari Essunfeld, Cecile Fabre, Thierry Fouchet, Cristina Garcia, Laura Garcia-Gomez, Patrick J. Gasda, Olivier Gasnault, Elisabeth Hausrath, Nina L. Lanza, Javier Laserna, Jeremie Lasue, Guillermo Lopez, Juan Manuel Madariaga, Lucia Mandon, Nicolas Mangold, Pierre-Yves Meslin, Marion Nachon, Anthony Nelson, Horton E. Newsom, Adriana Reyes-Newell, Scott Robinson, Fernando Rull, Shiv Sharma, Justin I Simon, Pablo Sobron, Imanol Torre Fernandez, Arya Udry, Dawn Venhaus, Scott McLennan, Richard V. Morris, Bethany L. Ehlmann
Response to comment on “Mercury isotope fractionation by internal demethylation and biomineralization reactions in seabirds: Implications for environmental mercury science”: Principles and limitations of source tracing and process tracing with stable isot Response to comment on “Mercury isotope fractionation by internal demethylation and biomineralization reactions in seabirds: Implications for environmental mercury science”: Principles and limitations of source tracing and process tracing with stable isot
No abstract available.
Authors
Alain Manceau, Romain Brossier, Sarah E. Janssen, Brett Poulin
Factors affecting spatiotemporal variation in survival of endangered winter-run Chinook Salmon outmigrating from the Sacramento River Factors affecting spatiotemporal variation in survival of endangered winter-run Chinook Salmon outmigrating from the Sacramento River
Among four extant and declining Chinook salmon (Oncorhynchus tshawytscha) runs in California’s Central Valley, none have declined as precipitously as Sacramento River winter-run Chinook Salmon. In addition to habitat loss, migratory winter-run employ a life history strategy to reside and feed in stopover habitats on their way from freshwaters to the ocean. This life history strategy is...
Authors
Jason L. Hassrick, Arnold J. Ammann, Russell Perry, Sara N. John, Miles E. Daniels
Major reorganization of the Snake River modulated by passage of the Yellowstone Hotspot Major reorganization of the Snake River modulated by passage of the Yellowstone Hotspot
The details and mechanisms for Neogene river reorganization in the U.S. Pacific Northwest and northern Rocky Mountains have been debated for over a century with key implications for how tectonic and volcanic systems modulate topographic development. To evaluate paleo-drainage networks, we produced an expansive data set and provenance analysis of detrital zircon U-Pb ages from Miocene to
Authors
Lydia M. Staisch, Jim E. O'Connor, Charles M. Cannon, Christopher S. Holm-Denoma, Paul K. Link, John Lasher, Jeremy A. Alexander
How many Ciscoes are needed for stocking in the Laurentian Great Lakes? How many Ciscoes are needed for stocking in the Laurentian Great Lakes?
Historically, Cisco Coregonus artedi and deepwater ciscoes Coregonus spp. were the most abundant and ecologically important fish species in the Laurentian Great Lakes, but anthropogenic influences caused nearly all populations to collapse by the 1970s. Fishery managers have begun exploring the feasibility of restoring populations throughout the basin, but questions regarding hatchery...
Authors
Benjamin J. Rook, Michael J. Hansen, Charles R. Bronte
Transforming Palmyra Atoll to native-tree dominance will increase net carbon storage and reduce dissolved organic carbon reef runoff Transforming Palmyra Atoll to native-tree dominance will increase net carbon storage and reduce dissolved organic carbon reef runoff
Native forests on tropical islands have been displaced by non-native species, leading to calls for their transformation. Simultaneously, there is increasing recognition that tropical forests can help sequester carbon that would otherwise enter the atmosphere. However, it is unclear if native forests sequester more or less carbon than human-altered landscapes. At Palmyra Atoll, efforts...
Authors
Kate Longley-Wood, Mary Engels, Kevin D. Lafferty, John P. McLaughlin, Alex Wegmann
Dermal denticle shedding rates vary between two captive shark species Dermal denticle shedding rates vary between two captive shark species
Shark dermal scale (denticle) accumulation in the fossil record can provide information about the abundance and composition of past shark communities. Denticles are shed continuously, such that a single shark leaves a scattered composite of many isolated denticles in sediments. However, the rate of denticle shedding as well as how these rates vary among shark species with different life...
Authors
Erin M. Dillon, Anshika Bagla, Kiera D. Plioplys, Douglas J. McCauley, Kevin D. Lafferty, Aaron O’Dea
A biological condition gradient for Caribbean coral reefs: Part II. Numeric rules using sessile benthic organisms A biological condition gradient for Caribbean coral reefs: Part II. Numeric rules using sessile benthic organisms
The Biological Condition Gradient (BCG) is a conceptual model used to describe incremental changes in biological condition along a gradient of increasing anthropogenic stress. As coral reefs collapse globally, scientists and managers are focused on how to sustain the crucial structure and functions, and the benefits that healthy coral reef ecosystems provide for many economies and...
Authors
Deborah L Santavy, Susan K Jackson, Benjamin Jessup, Christina Horstmann, Caroline Rogers, Ernesto Weil, Alina Szmant, David Cuevas Miranda, Brian K Walker, Christopher F.G. Jeffrey, David Ballantine, William S. Fisher, Randy Clark, Hector Ruiz Torres, Brandi Todd, Sandy Raimondo
Perils of life on the edge: Climatic threats to global diversity patterns of wetland macroinvertebrates Perils of life on the edge: Climatic threats to global diversity patterns of wetland macroinvertebrates
Climate change is rapidly driving global biodiversity declines. How wetland macroinvertebrate assemblages are responding is unclear, a concern given their vital function in these ecosystems. Using a data set from 769 minimally impacted depressional wetlands across the globe (467 temporary and 302 permanent), we evaluated how temperature and precipitation (average, range, variability)...
Authors
Luis B. Epele, Marta G. Grech, Emilio A. Williams-Subiza, Cristina Stenert, Kyle McLean, Hamish S. Greig, Leonardo Maltchik, Mateus M. Pires, Matthew S. Bird, Aurelie Boissezon, Dani Boix, Eliane Demierre, Patricia E. García, Stephanie Gascón, Michael Jeffries, Jamie M. Kneitel, Olga Loskutov, Luz M. Manzo, Gabriela Mataloni, Musa C. Mlambo, Beat Oertli, Jordi Sala, Erica E. Scheibler, Haitao Wu, Scott A Wissinger, Darold P. Batzer
Experimental inoculation trial to determine the effects of temperature and humidity on White-nose Syndrome in hibernating bats Experimental inoculation trial to determine the effects of temperature and humidity on White-nose Syndrome in hibernating bats
Disease results from interactions among the host, pathogen, and environment. Inoculation trials can quantify interactions among these players and explain aspects of disease ecology to inform management in variable and dynamic natural environments. White-nose Syndrome, a disease caused by the fungal pathogen, Pseudogymnoascus destructans (Pd), has caused severe population declines of...
Authors
Winifred F. Frick, Emily R. Johnson, Tina L. Cheng, Julia S. Lankton, Robin Warne, Jason Dallas, Katy L. Parise, Jeffrey T. Foster, Justin G. Boyles, Liam P. McGuire
Shifting precipitation regimes alter the phenology and population dynamics of low latitude ectotherms Shifting precipitation regimes alter the phenology and population dynamics of low latitude ectotherms
Predicting how species respond to changes in climate is critical to conserving biodiversity. Modeling efforts to date have largely centered on predicting the effects of warming temperatures on temperate species phenology. In and near the tropics, the effects of a warming planet on species phenology are more likely to be driven by changes in the seasonal precipitation cycle rather than...
Authors
Erica H Henry, Adam Terando, William F. Morris, Jaret C. Daniels, Nick M. Haddad
Sediment sources and sealed-pavement area drive polycyclic aromatic hydrocarbon and metal occurrence in urban streams Sediment sources and sealed-pavement area drive polycyclic aromatic hydrocarbon and metal occurrence in urban streams
Metals and polycyclic aromatic hydrocarbons (PAHs) are common pollutants in urban streambed sediment, yet their occurrence is highly variable and difficult to predict. To investigate sources of PAHs and metals to streambed sediment, we sampled pavement dust, soil, and streambed sediment in 10 urban watersheds in three regions of the United States and applied a fallout-radionuclide-based...
Authors
Peter C. Van Metre, Barbara Mahler, Sharon L. Qi, Allen C. Gellis, Christopher C. Fuller, Travis S. Schmidt