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Page 229, results 5701 - 5725

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Delineating the Pierre Shale from geophysical surveys within and near Ellsworth Air Force Base, South Dakota, 2019
Colton J. Medler, Todd M. Anderson
2021, Scientific Investigations Map 3474
The U.S. Geological Survey, in cooperation with the U.S. Air Force Civil Engineering Center, investigated the use of surface geophysical methods to delineate the top of the Cretaceous Pierre Shale along survey transects in selected areas within and near Ellsworth Air Force Base, South Dakota. Two complementary geophysical methods—electrical resistivity...
Identifying policy-relevant indicators for assessing landscape vegetation patterns to inform planning and management on multiple use public lands
Sarah K. Carter, Lucy Burris, Chris Domschke, Steven L Garman, Travis Haby, Benjamin R Harms, Emily Kachergis, Kevin Miller, S. E. Litschert
2021, Environmental Management (68) 426-443
Understanding the structure and composition of landscapes can empower agencies to effectively manage public lands for multiple uses while sustaining land health. Many landscape metrics exist, but they are not often used in public land decision-making. Our objectives were to (1) develop and (2) apply a process for identifying a...
Identification of low-frequency earthquakes on the San Andreas fault with deep learning
A. M. Thomas, A. Inbal, J. Searcy, David R. Shelly, R. Bürgmann
2021, Geophysical Research Letters (48)
Low-frequency earthquakes are a seismic manifestation of slow fault slip. Their emergent onsets, low amplitudes, and unique frequency characteristics make these events difficult to detect in continuous seismic data. Here, we train a convolutional neural network to detect low-frequency earthquakes near Parkfield, CA using the catalog of...
Two-dimensional hydraulic analyses of Joachim Creek, De Soto, Missouri
Kyle D. Hix, Paul H. Rydlund Jr., David C. Heimann
2021, Scientific Investigations Report 2021-5058
A two-dimensional hydraulic model; water-surface profiles; and digital maps of water-surface elevation, velocities, and water depths were developed for a 6.7-mile reach of Joachim Creek within and near the city of De Soto, Missouri. Water-surface profiles were generated for the 10-, 4-, 2-, 1-, and 0.2-percent annual exceedance probability (10-,...
Hydrogeologic framework and groundwater characterization in selected alluvial basins in the upper Rio Grande basin, Colorado, New Mexico, and Texas, United States, and Chihuahua, Mexico, 1980 to 2015
Natalie A. Houston, Jonathan V. Thomas, Linzy K. Foster, Diana E. Pedraza, Toby L. Welborn
2021, Scientific Investigations Report 2021-5035
Increasing demand for the limited water resources of the United States continues to put pressure on resource management agencies to balance the competing needs of ecosystem health with municipal, agricultural, and other uses. To meet these needs, the U.S. Geological Survey conducted a multiyear study to evaluate water resources in...
Exploring the potential of electrospray-Orbitrap for stable isotope analysis using nitrate as a model
Andreas Hilkert, J.K. Bohlke, Stanley J. Mroczkowski, Kyle L. Fort, Konstantin Aizikov, Xinchen T. Wang, Sebastian H. Kopf, Cajetan Neubauer
2021, Analytical Chemistry (93) 9139-9148
Widely used isotope ratio mass spectrometers have limited capabilities to measure metabolites, drugs, or small polyatomic ions without the loss of structural isotopic information. A new approach has recently been introduced that uses electrospray ionization Orbitrap to measure multidimensional isotope signatures of intact polar compounds. Using nitrate as a model...
Sources and risk factors for nitrate and microbial contamination of private household wells in the fractured dolomite aquifer of northeastern Wisconsin
Mark A. Borchardt, Joel P. Stokdyk, Burney A Kieke, Maureen A. Muldoon, Susan K. Spencer, Aaron D. Firnstahl, Davina Bonness, Randall J. Hunt, Tucker R. Burch
2021, Environmental Health Perspectives (129)
Background:Groundwater quality in the Silurian dolomite aquifer in northeastern Wisconsin, USA, has become contentious as dairy farms and exurban development expand.Objectives:We investigated private household wells in the region, determining the extent, sources, and risk factors of nitrate and microbial contamination.Methods:Total coliforms, Escherichia...
Probabilistic methodology for the assessment of original and recoverable coal resources, illustrated with an application to a coal bed in the Fort Union Formation, Wyoming
Ricardo A. Olea, Brian N. Shaffer, Jon E. Haacke, James A. Luppens
2021, Techniques and Methods 6-G1
Executive SummaryThe U.S. Geological Survey (USGS) has been using its Circular 891 for evaluating uncertainty in coal resource assessments for more than 35 years. Calculated cell tonnages are assigned to four qualitative reliability classes depending exclusively on distance to the nearest drill hole. The main appeal of this methodology, simplicity,...
Mapping the vulnerability of giant sequoias after extreme drought in California using remote sensing
Andres Baeza, Roberta E. Martin, Nathan L. Stephenson, Adrian Das, Paul Hardwick, Koren R. Nydick, Jeff Mallory, Michèle Slaton, Kirk Evans, Gregory P. Asner
2021, Ecological Applications (31)
Between 2012 and 2016, California suffered one of the most severe droughts on record. During this period Sequoiadendron giganteum (giant sequoias) in the Sequoia and Kings Canyon National Parks (SEKI), California, USA experienced canopy water content (CWC) loss, unprecedented foliage senescence, and, in a few cases, death. We...
Hyperspectral narrowband data propel gigantic leap in the earth remote sensing
Prasad Thenkabail, Itiya P. Aneece, Pardhasaradhi Teluguntla, Adam Oliphant
2021, Photogrammetric Engineering and Remote Sensing. (77) 461-467
Hyperspectral narrowbands (HNBs) capture data as nearly continuous “spectral signatures” rather than a “few spectral data points” along the electromagnetic spectrum as with multispectral broadbands (MBBs). Almost all of satellite remote sensing of the Earth in the twentieth century was conducted using MBB data from sensors such as the Landsat-series, Advanced...
Perceived barriers to the use of assisted colonization for climate sensitive species in the Hawaiian Islands
Shannon Rivera, Lucas Berio Fortini, Sheldon M. Plentovich, Melissa Price
2021, Environmental Management (68) 329-339
Conservation actions to safeguard climate change vulnerable species may not be utilized due to a variety of perceived barriers. Assisted colonization, the intentional movement and release of an organism outside its historical range, is one tool available for species predicted to lose habitat under future climate...
Reconstruction of an extreme flood hydrograph and morphodynamics of a meander bend in a high-peak discharge variability river (Powder River, USA)
Massimiliano Ghinassi, John A. Moody
2021, Sedimentology (68) 3549-3576
Understanding of morphodynamic processes associated with large-scale floods has recently improved following significant advances of modern technologies. Nevertheless, a clear link between flood discharge and in-channel sedimentation processes remains to be resolved. The hydrological and geomorphological data available for the meandering Powder River (Montana, USA) since...
Trait heritability and its implications for the management of an invasive vertebrate
Brenna A Levine, Marlis R Douglas, Amy A. Yackel Adams, Bjorn Lardner, Robert Reed, Julie A. Savidge, Michael E Douglas
2021, Biological Invasions (23) 3447-3456
Control methods that target specific traits of an invasive species can produce results contrary to the aims of management. If targeted phenotypes exhibit heritability, then it follows that the invasive species could evolve greater resistance to the applied control measures over time. Additional complications emerge if those traits targeted by...
Assessing the robustness of time-to-event models for estimating unmarked wildlife abundance using remote cameras
Kenneth E. Loonam, Paul M. Lukacs, David Edward Ausband, Michael S. Mitchell, Hugh S. Robinson
2021, Ecological Applications (31)
Recently developed methods, including time-to-event and space-to-event models, estimate the abundance of unmarked populations from encounter rates with camera trap arrays, addressing a gap in noninvasive wildlife monitoring. However, estimating abundance from encounter rates relies on assumptions that can be difficult to meet in the field, including random movement, population...
Surficial geology of the northern San Luis Valley, Saguache, Fremont, Custer, Alamosa, Rio Grande, Conejos, and Costilla Counties, Colorado
Chester A. Ruleman, Theodore R. Brandt
2021, Scientific Investigations Map 3475
The San Luis Valley and associated underlying basin of south-central Colorado and north-central New Mexico is the largest structural and hydrologic basin of the Rio Grande Rift and fluvial system. The surrounding San Juan and Sangre de Cristo Mountains reveal evidence of widespread volcanism and transtensional tectonism beginning in...
Hydrology of annual winter water level drawdown regimes in recreational lakes of Massachusetts, United States
Jason R. Carmignani, Allison H. Roy, Jason Stolarski, Todd Richards
2021, Lake and Reservoir Management (37) 339-359
Annual winter water level drawdown (WD) is a common lake management strategy to maintain recreational value by controlling nuisance macrophytes and preventing ice damage to shoreline infrastructure in lakes of the northeastern United States. The state of Massachusetts provides general guidelines for lake managers to implement and practice WDs. However,...
Climate and the latitudinal limits of subtropical reef development
Lauren T. Toth, William F. Precht, Alexander B. Modys, Anastasios Stathakopoulos, Martha L. Robbart, J. Harold Hudson, Anton E. Olenik, Bernhard M Riegl, Eugene A. Shinn, Richard B. Aronson
2021, Scientific Reports (11)
Climate plays a central role in coral-reef development, especially in marginal environments. The high-latitude reefs of southeast Florida are currently non-accreting, relict systems with low coral cover. This region also did not support the extensive Late Pleistocene reef development observed in many other locations around the world; however, there is...
The 2011-2019 Long Valley Caldera inflation: New insights from separation of superimposed geodetic signals and 3D modeling
F. Silverii, F. Pulvirenti, Emily K. Montgomery-Brown, A. Borsa, W. Neely
2021, Earth and Planetary Science Letters (569)
Increasingly accurate, and spatio-temporally dense, measurements of Earth surface movements enable us to identify multiple deformation patterns and highlight the need to properly characterize the related source processes. This is particularly important in tectonically active areas, where deformation measurement is crucial for monitoring ongoing processes and assessing future hazard....
As the prey thickens: Rainbow trout select prey based upon width not length
Michael J. Dodrill, Charles B. Yackulic, Theodore Kennedy, Michael D. Yard, Josh Korman
2021, Canadian Journal of Fisheries and Aquatic Sciences (78) 809-819
Drift-feeding fish are typically considered size-selective predators. Yet, few studies have explicitly tested which aspect of prey “size” best explains size selection by drift-foraging fish. Here, we develop a Bayesian discrete choice model to evaluate how attributes of both prey and predator simultaneously influence size-selective foraging. We apply the model...
Refining sampling protocols for cavefishes and cave crayfishes to account for environmental variation
J.B. Mouser, Shannon K. Brewer, M.L. Niemiller, M. Mollenhauer, Van Den Bussche
2021, Subterranean Biology (39) 79-105
Subterranean habitats support a diverse array of organisms and represent imperative habitats in many conservation strategies; however, subterranean habitats are one of the most difficult environments to study. Accounting for variable sampling detection is necessary to properly evaluate conservation options for rare species such as karst and other groundwater organisms....
Demography of the Oregon spotted frog along a hydrologically modified river
Jennifer Rowe, Adam Duarte, Christopher Pearl, Brome McCreary, Patricia Haggerty, John W. Jones, Michael J. Adams
2021, Ecosphere (12)
Altered flow regimes can contribute to dissociation between life history strategies and environmental conditions, leading to reduced persistence reported for many wildlife populations inhabiting regulated rivers. The Oregon spotted frog (Rana pretiosa) is a threatened species occurring in floodplains, ponds, and wetlands in the Pacific Northwest...
Endophytic bacteria in grass crop growth promotion and biostimulation
James F. White, Xiaoqian Chang, Kathryn L. Kingsley, Qiuwei Zhang, Peerapol Chiaranunt, April Micci, Fernando Velazquez, Matthew T. Elmore, Sharron Crane, Shanjia Li, Jiaxin Lu, Maria Molina Cobos, Natalia Gonzalez-Benitez, Miguel J Beltran-Garcia, Kurt P. Kowalski
2021, Grass Research (1)
Plants naturally carry microbes on seeds and within seeds that may facilitate development and early survival of seedlings. Some crops have lost seed-vectored microbes in the process of domestication or during seed storage and seed treatment. Biostimulant microbes from wild plants were used by pre-modern cultures to re-acquire beneficial...
Resilience to fire and resistance to annual grass invasion in sagebrush ecosystems of US National Parks
Thomas Rodhouse, Jeffrey Lonneker, Lisa Bowersock, Diana Popp, Jamela Thompson, Gordon Dicus, Kathryn M. Irvine
2021, Global Ecology and Conservation (28)
Western North American sagebrush shrublands and steppe face accelerating risks from fire-driven feedback loops that transition these ecosystems into self-reinforcing states dominated by invasive annual grasses. In response, sagebrush conservation decision-making is increasingly done through the lens of resilience to fire and annual grass invasion resistance. Operationalizing...
Age and tectonic setting of the Quinebaug-Marlboro belt and implications for the history of Ganderian crustal fragments in southeastern New England, USA
Gregory J. Walsh, John N. Aleinikoff, Robert A. Ayuso, Robert P. Wintsch
2021, Geosphere (4) 1038-1100
Crustal fragments underlain by high-grade rocks represent a challenge to plate reconstructions, and integrated mapping, geochronology, and geochemistry enable the unravelling of the temporal and spatial history of exotic crustal blocks. The Quinebaug-Marlboro belt (QMB) is an enigmatic fragment on the trailing edge of the...
Monitoring abundance of aggregated animals (Florida manatees) using an unmanned aerial system (UAS)
Holly H Edwards, Jeffrey A. Hostetler, Bradley M Stith, Julien Martin
2021, Scientific Reports (11)
Imperfect detection is an important problem when counting wildlife, but new technologies such as unmanned aerial systems (UAS) can help overcome this obstacle. We used data collected by a UAS and a Bayesian closed capture-mark-recapture model to estimate abundance and distribution while accounting for imperfect detection...