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Publications

Browse more than 160,000 publications authored by our scientists over the past 100+ year history of the USGS.  Publications available are: USGS-authored journal articles, series reports, book chapters, other government publications, and more.

Filter Total Items: 171257

Spatial extent of seagrasses (Zostera marina and Ruppia maritima) along the central Pacific coast of Baja California, Mexico, 1999–2000

The seagrasses eelgrass (Zostera marina) and widgeongrass (Ruppia maritima) are prominent features of coastal lagoons along the Pacific coast of Baja California, Mexico, supporting a rich diversity of marine life. Yet little is known about their spatial distribution in this region. This is a concern because of declining trends in the abundance and distribution of seagrass in parts of northern Baja
Authors
David H. Ward, Alexandra Morton, Carl J. Markon, Kyle R. Hogrefe

Plant community trajectories following livestock exclusion for conservation vary and hinge on initial invasion and soil-biocrust conditions in shrub steppe

Adjustments or complete withdrawal of livestock grazing are among the most common conservation actions in semiarid uplands, but outcomes can vary considerably with ecological context. Invasion by exotic annual grasses and the excessive wildfire they promote are increasing threats to semiarid shrub-steppe, and plant-community response to livestock exclusion in these areas may be complicated by the
Authors
Matthew J. Germino, Chad Raymond Kluender, Christopher R. Anthony

Abundance of eelgrass (Zostera marina) at key Black Brant (Branta bernicla nigricans) wintering sites along the northern Pacific coast of Baja California, Mexico, 1998–2012

Trends in the abundance and distribution of eelgrass (Zostera marina), the primary winter forage of black brant (Branta bernicla nigricans), was evaluated at three major wintering sites for black brant along the northern Pacific coast of Baja California, Mexico. This region of northwestern Mexico contains significant beds of eelgrass that were showing signs of decline, which may negatively affect
Authors
David H. Ward

Sentinel responses of Arctic freshwater systems to climate: linkages, evidence, and a roadmap for future research

While the sentinel nature of freshwater systems is now well recognized, widespread integration of freshwater processes and patterns into our understanding of broader climate-driven Arctic terrestrial ecosystem change has been slow. We review the current understanding across Arctic freshwater systems of key sentinel responses to climate, which are attributes of these systems with demonstrated and s
Authors
Jasmine E. Saros, Christoper D. Arp, Frederic Bouchard, Jerome Comte, Raoul-Marie Couture, Joshua F. Dean, Melissa Lafreniere, Sally MacIntyre, Suzanne McGowan, Milla Rautio, Clay Prater, Suzanne E. Tank, Michelle A. Walvoord, Kimberly Wickland, Dermot Antoniades, Paola Ayala-Borda, Joao Canario, Travis W. Drake, Diogo Folhas, Vaclava Hazukova, Henriikka Kivila, Yohanna Klanten, Scott Lamoreux, Isabelle Laurion, Rachel M. Pilla, Jorien E. Vonk, Scott Zolkos, Warwick Vincent

Genetic analysis of North American Phragmites australis guides management approaches

Phragmites australis subsp. australis is an invasive and ecologically detrimental plant in multiple regions of North America. Its co-occurrence with the native subspecies, and multiple instances of hybridization, has created the need to differentiate Phragmites subspecies or haplotypes so that management can be appropriately targeted to the invader. We compiled a review of current genetic discrimi
Authors
Denise L. Lindsay, Joanna Freeland, Ping Gong, Xin Guan, Nathan E Harms, Kurt P. Kowalski, Richard F. Lance, Dong-Ha Oh, Bradley T Sartain, Douglas L Wendell

The hydroclimate niche: A tool for predicting and managing riparian plant community responses to streamflow seasonality

Habitat suitability is a consequence of interacting environmental factors. In riparian ecosystems, suitable plant habitat is influenced by interactions between stream hydrology and climate, hereafter referred to as “hydroclimate”. We tested the hypothesis that hydroclimate variables would improve the fit of ecological niche models for a suite of riparian species using occurrence data from the west
Authors
Bradley J. Butterfield, Emily C. Palmquist, Charles Yackulic

Bulk and intramolecular carbon isotopic compositions of hydrocarbon gases from laboratory pyrolysis of oil shale of the Green River Formation: Implications for isotope structures of kerogens

Evaluation of intramolecular isotope distributions within organic compounds can provide important insights into gas formation processes and structural properties of gas-generating precursors, such as kerogen, bitumen, and oil, in natural reservoirs. Until recently, little has been known about the intramolecular isotope distributions within kerogens. In this study, we conducted systematic pyrolysis
Authors
Xiaoqiang Li, Justin E. Birdwell, Juske Horita

Predicted uranium and radon concentrations in New Hampshire (USA) groundwater—Using Multi Order Hydrologic Position as predictors

Two radioactive elements, uranium (U) and radon (Rn), which are of potential concern in New Hampshire (NH) groundwater, are investigated. Exceedance probability maps are tools to highlight locations where the concentrations of undesirable substances in the groundwater may be elevated. Two forms of statistical analysis are used to create exceedance probability maps for U and Rn in NH groundwater. T
Authors
Richard B. Moore, Kenneth Belitz, Joseph D. Ayotte, Terri L. Arnold, Laura Hayes, Jennifer B. Sharpe, J. Jeffrey Starn

Patterns and controls of foliar nutrient stoichiometry and flexibility across United States forests

Plant element stoichiometry and stoichiometric flexibility strongly regulate ecosystem responses to global change. Here, we tested three potential mechanistic drivers (climate, soil nutrients, and plant taxonomy) of both using paired foliar and soil nutrient data from terrestrial forested National Ecological Observatory Network sites across the USA. We found that broad patterns of foliar nitrogen
Authors
Katherine A Kynarski, Fiona M. Soper, Sasha C. Reed, William R Wieder, Cory C Cleveland

Backpack electrofishing does not contribute to external signs of gas bubble trauma in sculpins

We exposed prickly sculpin Cottus asper and reticulate sculpin Cottus perplexus to electroshock and sham treatments in a controlled laboratory setting to determine if backpack electrofishing contributed to or exacerbated external signs of gas bubble trauma (GBT) in fish exposed to elevated total dissolved gas (TDG) levels. Fish were exposed to 115, 120 and 125% TDG (measured as percent of saturati
Authors
Kenneth Tiffan, Nicole Joy Eller

Systematic mapping of the ocean-continent transform plate boundary of the Queen Charlotte fault system, southeastern Alaska and western British Columbia—A preliminary bathymetric terrain model

In 2015, U.S. Geological Survey scientists in collaboration with scientists from other institutions began a study of the Queen Charlotte fault—the first systematic study of the fault in more than three decades. The primary goal of the study was to gain a better understanding of the earthquake, tsunami, and underwater-landslide hazards throughout southeastern Alaska, as well as gather data to devel
Authors
Brian D. Andrews, Daniel S. Brothers, Peter Dartnell, J. Vaughn Barrie, Peter J. Haeussler, Kristen M. Green, H. Gary Greene, Nathaniel C. Miller, Jared W. Kluesner, Uri S. ten Brink