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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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Method development for a short-term 7-day toxicity test with unionid mussels Method development for a short-term 7-day toxicity test with unionid mussels
The US Environmental Protection Agency's short-term freshwater effluent test methods include a fish (Pimephales promelas), a cladoceran (Ceriodaphnia dubia), and a green alga (Raphidocelis subcapitata). There is a recognized need for additional taxa to accompany the three standard species for effluent testing. An appropriate additional taxon is unionid mussels because mussels are widely
Authors
Ning Wang, James L. Kunz, Douglas K. Hardesty, Jeffery A. Steevens, Teresa J. Norberg-King, Edward J. Hammer, Candice R. Bauer, Tom Augspurger, Suzanne Dunn, David Martinez, M. Christopher Barnhart, Jordan Murray, Marcus Bowersox, John F. Roberts, Robert B. Bringolf, Robert Ratajczak, Serena Ciparis, W. Gregory Cope, Sean B. Buczek, Daniel Farrar, Lauren May, Mailee Garton, Patricia L. Gillis, James Bennett, Joseph Salerno, Brian Hester, Richard Lockwood, Christopher Tarr, Dennis McIntyre, Jonathan Wardell
Sampling design workflows and tools to support adaptive monitoring and management Sampling design workflows and tools to support adaptive monitoring and management
On the Ground • Adaptive land management requires monitoring of resource conditions, which requires choices about where and when to monitor a landscape. • Designing a sampling design for a monitoring program can be broken down in to eight steps: identifying questions, defining objectives, selecting reporting units, deciding data collection methods, defining the sample frame, selecting an...
Authors
Nelson G. Stauffer, Michael C. Duniway, Jason W. Karl, Travis W. Nauman
Ecosystem carbon balance in the Hawaiian Islands under different scenarios of future climate and land use change Ecosystem carbon balance in the Hawaiian Islands under different scenarios of future climate and land use change
The State of Hawai'i passed legislation to be carbon neutral by 2045, a goal that will partly depend on carbon sequestration by terrestrial ecosystems. However, there is considerable uncertainty surrounding the future direction and magnitude of the land carbon sink in the Hawaiian Islands. We used the Land Use and Carbon Scenario Simulator (LUCAS), a spatially explicit stochastic...
Authors
Paul C. Selmants, Benjamin M. Sleeter, Jinxun Liu, Tamara Wilson, Clay Trauernicht, Abby G. Frazier, Gregory P. Asner
Effect of an algal amendment on the microbial conversion of coal to methane at different sulfate concentrations from the Powder River Basin, USA Effect of an algal amendment on the microbial conversion of coal to methane at different sulfate concentrations from the Powder River Basin, USA
Biogenic methane is estimated to account for one-fifth of the natural gas worldwide and there is great interest in controlling methane from different sources. Biogenic coalbed methane (CBM) production relies on syntrophic associations between fermentative bacteria and methanogenic archaea to anaerobically degrade recalcitrant coal and produce methanogenic substrates. However, very little...
Authors
Heidi J. Smith, Hannah S. Schweitzer, Elliott P. Barnhart, William H. Orem, Robin Gerlach, Matthew W. Fields
Compositional evolution of organic matter in Boquillas Shale across a thermal gradient at the single particle level Compositional evolution of organic matter in Boquillas Shale across a thermal gradient at the single particle level
The molecular composition of petroliferous organic matter and its compositional evolution throughout thermal maturation provides insight for understanding petroleum generation. This information is critical for understanding hydrocarbon resources in unconventional reservoirs, as source rock organic matter is highly dispersed, in contact with the surrounding mineral matrix, and may occur...
Authors
Justin E. Birdwell, Aaron M. Jubb, Paul C. Hackley, Javin J. Hatcherian
Demographic risk assessment for a harvested species threatened by climate change: Polar bears in the Chukchi Sea Demographic risk assessment for a harvested species threatened by climate change: Polar bears in the Chukchi Sea
Climate change threatens global biodiversity. Many species vulnerable to climate change are important to humans for nutritional, cultural, and economic reasons. Polar bears Ursus maritimus are threatened by sea-ice loss and represent a subsistence resource for Indigenous people. We applied a novel population modeling-management framework that is based on species life history and accounts...
Authors
Eric V. Regehr, Michael C. Runge, Andrew L. Von Duyke, Ryan R. Wilson, Lori Polasek, Karyn D. Rode, Nathan J. Hostetter, Sarah J. Converse
Populations using public-supply groundwater in the conterminous U.S. 2010; Identifying the wells, hydrogeologic regions, and hydrogeologic mapping units Populations using public-supply groundwater in the conterminous U.S. 2010; Identifying the wells, hydrogeologic regions, and hydrogeologic mapping units
Most Americans receive their drinking water from publicly supplied sources, a large portion of it from groundwater. Mapping these populations consistently and at a high resolution is important for understanding where the resource is used and needs to be protected. The results show that 269 million people are supplied by public supply, 107 million are supplied by groundwater and 162...
Authors
Tyler D. Johnson, Kenneth Belitz, Leon J. Kauffman, Elise Watson, John T. Wilson
Development of aquaculture protocols and gonadal differentiation of green sunfish (Lepomis cyanellus) Development of aquaculture protocols and gonadal differentiation of green sunfish (Lepomis cyanellus)
We provide detailed rearing methods and describe green sunfish (Lepomis cyanellus) gonadal development and histological differentiation for both sexes. Developing in-depth aquaculture protocols and describing the gonadal differentiation of green sunfish could facilitate strategies to control nuisance populations, enhance stocking programs, and provide information for this species' use in...
Authors
Chad N. Teal, Daniel J. Schill, Susan B. Fogelson, Colby M. Roberts, Kevin Fitzsimmons, Scott A. Bonar
Improved fire severity mapping in the North American boreal forest using a hybrid composite method Improved fire severity mapping in the North American boreal forest using a hybrid composite method
Fire severity is a key driver shaping the ecological structure and function of North American boreal ecosystems, a biome dominated by large, high-intensity wildfires. Satellite-derived burn severity maps have been an important tool in these remote landscapes for both fire and resource management. The conventional methodology to produce satellite-inferred fire severity maps generally...
Authors
Lisa M. Holsinger, Sean Parks, Lisa Saperstein, Rachel A. Loehman, Ellen Whitman, Jennifer L. Barnes, Marc-André Parisien
Late Cenozoic paleogeographic reconstruction of the San Francisco Bay Area from analysis of stratigraphy, tectonics, and tephrochronology Late Cenozoic paleogeographic reconstruction of the San Francisco Bay Area from analysis of stratigraphy, tectonics, and tephrochronology
The Neogene stratigraphic and tectonic history of the Mount Diablo area is a consequence of the passage of the Mendocino Triple Junction (MTJ) by the San Francisco Bay area between 12 and 6 Ma, volcanism above a slab-window trailing the MTJ, and crustal transpression beginning ~8-6 Ma, when the Pacific Plate and Sierra Nevada microplate began to converge obliquely. Between ~12-6 Ma...
Authors
Andrei Sarna-Wojcicki
Late Cenozoic tephrochronology of the Mount Diablo area within the evolving plate-tectonic boundary zone of northern California Late Cenozoic tephrochronology of the Mount Diablo area within the evolving plate-tectonic boundary zone of northern California
We present a tephrochronologic/chronostratigraphic database for the Mount Diablo area and greater San Francisco Bay region that provides a spatial and temporal framework for geologic studies in the region, including stratigraphy, paleogeography, tectonics, quantification of earth surface processes, recurrence of natural hazards, and climate change. We identified and correlated 34 tephra...
Authors
Andrei Sarna-Wojcicki, Raymond Sullivan, Alan L. Deino, Laura Walkup, J. Ross Wagner, Elmira Wan
A decision tool to identify population management strategies for common ravens and other avian predators A decision tool to identify population management strategies for common ravens and other avian predators
Some avian species have developed the capacity to leverage resource subsidies associated with human manipulated landscapes to increase population densities in habitats with naturally low carrying capacities. Elevated corvid densities and new territory establishment have led to an unsustainable increase in depredation pressure on sympatric native wildlife prey populations as well as in...
Authors
Andrea Faye Currylow, Brenda Hanley, Kerry L. Holcomb, Timothy Shields, Stephen Boland, William Boarman, Mercy Vaughn