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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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Estimating the effects of fish quality and size on the economic value of fishing in Oklahoma streams and rivers: A revealed preference and contingent behavior approach Estimating the effects of fish quality and size on the economic value of fishing in Oklahoma streams and rivers: A revealed preference and contingent behavior approach
Fishing in Oklahoma’s rivers and streams provides a unique experience for anglers in the state. Despite its popularity, information on total demand and economic benefits associated with stream fishing is limited in the state. Research on the role of site quality indicators, such as fish size and quantity, on recreational fishing has shown mixed results. Whether fish size or quantity...
Authors
O. Joshi, B. Chapagain, James M. Long, B. York, A.T. Taylor
Understanding grass invasion, fire severity, and Acacia koa regeneration for forest restoration in Hawaiʻi Volcanoes National Park Understanding grass invasion, fire severity, and Acacia koa regeneration for forest restoration in Hawaiʻi Volcanoes National Park
With invasive grasses increasing wildfire occurrence worldwide, a better understanding of the relationships between native plants, fire, and invasive grass is needed to help restoration plans facilitate ecosystem resilience. Invasive grasses are particularly problematic for altering fire regimes in the tropics, yet in Hawaiʻi, restoration sites are often planted with monocultures of the...
Authors
Hamilton Natalia, Stephanie G. Yelenik, Tara Durboraw, Robert Cox, Nathan S. Gill
A petrological and conceptual model of Mayon volcano (Philippines) as an example of an open-vent volcano A petrological and conceptual model of Mayon volcano (Philippines) as an example of an open-vent volcano
Mayon is a basaltic andesitic, open-vent volcano characterized by persistent passive degassing from the summit at 2463 m above sea level. Mid-size (200 orthopyroxene crystals reveal magma mixing timescales that range from a few days to about 65 years, but the majority are shorter than the decadal inter-eruptive repose period. This implies that magma intrusion at Mayon has been nearly...
Authors
Dawn Catherine Sweeney Ruth, Fidel Costa
Experimental design and data relevance in a volcanic ash-leachate health study: Letter to the Editor re. Barone et al. (2021) ‘Surface reactivity of Etna volcanic ash and evaluation of health risks’ Experimental design and data relevance in a volcanic ash-leachate health study: Letter to the Editor re. Barone et al. (2021) ‘Surface reactivity of Etna volcanic ash and evaluation of health risks’
No abstract available.
Authors
Carol Stewart, David Damby, Ines Tomasek, Claire J. Horwell
The potential of satellite remote sensing time series to uncover wetland phenology under unique challenges of tidal setting The potential of satellite remote sensing time series to uncover wetland phenology under unique challenges of tidal setting
While growth history of vegetation within upland systems is well studied, plant phenology within coastal tidal systems is less understood. Landscape-scale, satellite-derived indicators of plant greenness may not adequately represent seasonality of vegetation biomass and productivity within tidal wetlands due to limitations of cloud cover, satellite temporal frequency and attenu-ation of...
Authors
Gwendolyn Joelle Miller, Iryna Dronova, Patricia Oikawa, Sara Helen Knox, Lisamarie Windham-Myers, Julie Shahan, Ellen Stuart-Haëntjens
Urban proximity while breeding is not a predictor of perfluoroalkyl substance contamination in the eggs of brown pelicans Urban proximity while breeding is not a predictor of perfluoroalkyl substance contamination in the eggs of brown pelicans
Identifying sources of exposure to chemical stressors is difficult when both target organisms and stressors are highly mobile. While previous studies have demonstrated that populations of some organisms proximal to urban centers may display increased burdens of human-created chemicals compared to more distal populations, this relationship may not be universal when applied to organisms...
Authors
B. P. Wilkinson, A. R. Robuck, R. Lohman, H. M. Pickard, Patrick G.R. Jodice
Phenotypic variation in Brook Trout Salvelinus fontinalis (Mitchill) at broad spatial scales makes morphology an insufficient basis for taxonomic reclassification of the species Phenotypic variation in Brook Trout Salvelinus fontinalis (Mitchill) at broad spatial scales makes morphology an insufficient basis for taxonomic reclassification of the species
It was recently proposed that there are three new species of Salvelinus with microendemic distributions in the Great Smoky Mountains National Park, Tennessee, USA. The three species of Salvelinus were hypothesized to be distinct from their congener Brook Trout S. fontinalis based on three meristic traits—pored lateral-line scales, vertebral counts, and number of basihyal teeth. After...
Authors
Shannon L. White, David C. Kazyak, Richard C Harrington, Matt A. Kulp, Jacob M Rash, T. Casey Weathers, Thomas J Near
If you give a clam an estuary: The story of potamocorbula If you give a clam an estuary: The story of potamocorbula
When you look at San Francisco Bay, what animals do you see? You may see lots of fish swimming around and birds flying above. What you DON’T see is Potamocorbula, a little clam that has had a big impact. Many years ago, ships accidentally brought Potamocorbula into the Bay. Pretty soon, Potamocorbula spread out all over in large numbers! Clams pump water over their gills and eat small...
Authors
Kelly H. Shrader, Emily L. Zierdt Smith, Francis Parchaso, Janet K. Thompson
The structure and volume of large geysers in Yellowstone National Park, USA and the mineralogy and chemistry of their silica sinter deposits The structure and volume of large geysers in Yellowstone National Park, USA and the mineralogy and chemistry of their silica sinter deposits
Siliceous sinter is formed by biogenic and abiogenic opal deposition around hot springs and geysers. Using Structure-from-Motion photogrammetry we generated three-dimensional models of Giant and Castle Geysers from the Upper Geyser Basin of Yellowstone National Park. We use these models to calculate an approximate mass of sinter for each (~2 and ~ 5 kton, respectively) and estimate a...
Authors
Dakota Churchill, Michael Manga, Shaul Hurwitz, Sara Peek, David Damby, Richard Conrey, John R. Wood, R. Blaine McCleskey, William E. Keller, Behnaz Hosseini, Jefferson D.G. Hungerford
Improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS) Improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS)
We describe recent improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS), which continues to represent our most advanced and complete earthquake forecast in terms of relaxing segmentation assumptions and representing multifault ruptures, elastic‐rebound effects, and spatiotemporal clustering (the latter to represent aftershocks and otherwise...
Authors
Edward H. Field, Kevin R. Milner, Morgan T. Page, William H. Savran, Nicholas van der Elst
Estimating and forecasting time-varying groundwater recharge in fractured rock: A state-space formulation with preferential and diffuse flow to the water table Estimating and forecasting time-varying groundwater recharge in fractured rock: A state-space formulation with preferential and diffuse flow to the water table
Rapid infiltration following precipitation may result in groundwater contamination from surface contaminants or pathogens. In fractured rock, contaminants can migrate rapidly to points of groundwater withdrawals. In contrast to the temporal availability of groundwater quality chemical indicators, meteorological and groundwater level observations are available in real-time to estimate...
Authors
Allen M. Shapiro, Frederick Day-Lewis
Global drivers of avian haemosporidian infections vary across zoogeographical regions Global drivers of avian haemosporidian infections vary across zoogeographical regions
Aim: Macroecological analyses provide valuable insights into factors that influence how parasites are distributed across space and among hosts. Amid large uncertainties that arise when generalizing from local and regional findings, hierarchical approaches applied to global datasets are required to determine whether drivers of parasite infection patterns vary across scales. We assessed...
Authors
Alan Fecchio, Nicholas J. Clark, Jeffrey A Bell, Heather Skeen, Holly L Lutz, Gabriel M De La Torre, Jefferson A Vaughan, Vasyl V. Tkach, Fabio Schunck, Francisco C Ferreira, Erika M Braga, Camile Lugarini, Wanyoike Wamiti, Janice H Dispoto, Spencer C Galen, Karin Kirchgatter, M. Cecilia Sagario, Victor R Cueto, Daniel Gonzalez-Acuna, Mizue Inumaru, Yukita Sato, Yvonne R. Schumm, Petra Quillfeldt, Irene Pellegrino, Guha Dharmarajan, Pooja Gupta, V. V. Robin, Arif Ciloglu, Alparslan Yildirim, Xi Huang, Leonardo Chapa-Vargas, Paulina Alvarez-Mendizabal, Diego Santiago-Alarcon, Sergei V. Drovetski, Olof Hellgren, Gary Voelker, Robert E Ricklefs, Shannon Hackett, Michael D Collins, Jason D Weckstein, Konstans Wells