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Page 959, results 23951 - 23975

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Stable isotope analyses of oxygen (18O:17O:16O) and chlorine (37Cl:35Cl) in perchlorate: reference materials, calibrations, methods, and interferences
J.K. Bohlke, Stanley J. Mroczkowski, Neil C. Sturchio, Linnea J. Heraty, Kent W. Richman, Donald B. Sullivan, Kris N. Griffith, Baohua Gu, Paul B. Hatzinger
2017, Rapid Communications in Mass Spectrometry (31) 85-110
RationalePerchlorate (ClO4−) is a common trace constituent of water, soils, and plants; it has both natural and synthetic sources and is subject to biodegradation. The stable isotope ratios of Cl and O provide three independent quantities for ClO4− source attribution and natural attenuation studies: δ37Cl, δ18O, and δ17O (or Δ17O...
Undiscovered porphyry copper resources in the Urals—A probabilistic mineral resource assessment
Jane M. Hammarstrom, Mark J. Mihalasky, Stephen Ludington, Jeffrey Phillips, Byron R. Berger, Paul Denning, Connie Dicken, John C. Mars, Michael L. Zientek, Richard J. Herrington, Reimar Seltmann
2017, Ore Geology Reviews (85) 181-203
A probabilistic mineral resource assessment of metal resources in undiscovered porphyry copper deposits of the Ural Mountains in Russia and Kazakhstan was done using a quantitative form of mineral resource assessment. Permissive tracts were delineated on the basis of mapped and inferred subsurface distributions of igneous rocks assigned to...
Spatiotemporal variability of snow depletion curves derived from SNODAS for the conterminous United States, 2004-2013
Jessica M. Driscoll, Lauren E. Hay, Andrew R. Bock
2017, Journal of the American Water Resources Association (53) 655-666
Assessment of water resources at a national scale is critical for understanding their vulnerability to future change in policy and climate. Representation of the spatiotemporal variability in snowmelt processes in continental-scale hydrologic models is critical for assessment of water resource response to continued climate change. Continental-extent hydrologic models such as...
Drawing a line in the sand: Effectiveness of off-highway vehicle management in California's Sonoran desert
Nathan Custer, Lesley A. Defalco, Kenneth E. Nussear, Todd C. Esque
2017, Journal of Environmental Management (193) 448-457
Public land policies manage multiple uses while striving to protect vulnerable plant and wildlife habitats from degradation; yet the effectiveness of such policies are infrequently evaluated, particularly for remote landscapes that are difficult to monitor. We assessed the use and impacts of recreational vehicles on Mojave Desert washes (intermittent streams)...
Do we need demographic data to forecast plant population dynamics?
Andrew T. Tredennick, Mevin Hooten, Peter B. Adler
2017, Methods in Ecology and Evolution (8) 541-551
Rapid environmental change has generated growing interest in forecasts of future population trajectories. Traditional population models built with detailed demographic observations from one study site can address the impacts of environmental change at particular locations, but are difficult to scale up to the landscape and regional scales...
Functional visual sensitivity to ultraviolet wavelengths in the Pileated Woodpecker (Dryocopus pileatus), and its influence on foraging substrate selection
Sean T. O’Daniels, Dylan C. Kesler, Jeanne D. Mihail, Elisabeth B. Webb, Scott J. Werner
2017, Physiology & Behavior (174) 144-154
Most diurnal birds are presumed visually sensitive to near ultraviolet (UV) wavelengths, however, controlled behavioral studies investigating UV sensitivity remain few. Although woodpeckers are important as primary cavity excavators and nuisance animals, published work on their visual systems is limited. We developed a novel foraging-based behavioral assay designed to test...
Experimental evaluation of four ground-motion scaling methods for dynamic response-history analysis of nonlinear structures
Andrew P. O’Donnell, Yahya C. Kurama, Erol Kalkan, Alexandros A. Taflanidis
2017, Bulletin of Earthquake Engineering (15) 1899-1924
This paper experimentally evaluates four methods to scale earthquake ground-motions within an ensemble of records to minimize the statistical dispersion and maximize the accuracy in the dynamic peak roof drift demand and peak inter-story drift demand estimates from response-history analyses of nonlinear building structures. The scaling methods that are investigated...
Creating multithemed ecological regions for macroscale ecology: Testing a flexible, repeatable, and accessible clustering method
Kendra Spence Cheruvelil, Shuai Yuan, Katherine E. Webster, Pang-Ning Tan, Jean-Francois Lapierre, Sarah M. Collins, C. Emi Fergus, Caren E. Scott, Emily Norton Henry, Patricia A. Soranno, Christopher T. Filstrup, Tyler Wagner
2017, Ecology and Evolution (7) 3046-3058
Understanding broad-scale ecological patterns and processes often involves accounting for regional-scale heterogeneity. A common way to do so is to include ecological regions in sampling schemes and empirical models. However, most existing ecological regions were developed for specific purposes, using a limited set of geospatial features and irreproducible methods. Our...
Microbial formation of labile organic carbon in Antarctic glacial environments
H.J. Smith, R. Foster, D.M. McKnight, John T. Lisle, S. Littmann, M.M.M. Kuypers, C.M. Foreman
2017, Nature Geoscience (10) 356-359
Roughly six petagrams of organic carbon are stored within ice worldwide. This organic carbon is thought to be of old age and highly bioavailable. Along with storage of ancient and new atmospherically deposited organic carbon, microorganisms may contribute substantially to the glacial organic carbon pool. Models of glacial microbial carbon...
Using variance structure to quantify responses to perturbation in fish catches
Tiffany E. Vidal, Brian J. Irwin, Tyler Wagner, Lars G. Rudstam, James R. Jackson, James R. Bence
2017, Transactions of the American Fisheries Society (146) 584-593
We present a case study evaluation of gill-net catches of Walleye Sander vitreus to assess potential effects of large-scale changes in Oneida Lake, New York, including the disruption of trophic interactions by double-crested cormorants Phalacrocorax auritus and invasive dreissenid mussels. We used the empirical long-term gill-net time series and a...
National Park Service Vegetation Mapping Inventory Program: Appalachian National Scenic Trail vegetation mapping project
Kevin D. Hop, Andrew C. Strassman, Mark Hall, Shannon Menard, Ery Largay, Stephanie Sattler, Erin E. Hoy, Janis Ruhser, Enrika Hlavacek, Jennifer Dieck
2017, Natural Resource Report NPS/NETN/NRR—2017/1437
The National Park Service (NPS) Vegetation Mapping Inventory (VMI) Program classifies, describes, and maps existing vegetation of national park units for the NPS Natural Resource Inventory and Monitoring (I&M) Program. The NPS VMI Program is managed by the NPS I&M Division and provides baseline vegetation information to the NPS Natural...
Freshwater mussels (Unionidae): Central and West Texas Final Report
Charles R. Randklev, Nathan Johnson, T. J. Miller, J.M. Morton, J. Dudding, K. Skow, B. Boseman, M. Hart, E.T. Tsakiris, K. Inoue, R.R. Lopez
2017, Report, Texas A&M Institute of Renewable Natural Resources
The goal of this study was two-fold: (1) assess the taxonomic identity and phylogenetic placement of Quadrula aurea (Golden Orb) [Federal Candidate], Quadrula houstonensis (Smooth Pimpleback) [Federal Candidate], and Quadrula petrina (Texas Pimpleback) [Federal Candidate] through mitochondrial and nuclear DNA sequencing; and (2) provided additional information on the distribution and abundance for mussel species...
Different historical fire–climate patterns in California
Jon E. Keeley, Alexandra D. Syphard
2017, International Journal of Wildland Fire (26) 253-268
The relationship between annual variation in area burned and seasonal temperatures and precipitation was investigated for the major climate divisions in California. Historical analyses showed marked differences in fires on montane and foothill landscapes. Based on roughly a century of data, there are five important lessons on fire–climate relationships in...
Comparative precision of age estimates from two southern reservoir populations of paddlefish [Polyodon spathula (Walbaum, 1792)]
James M. Long, Ashley Nealis
2017, Journal of Applied Ichthyology (33) 819-820
The aim of the study was to determine whether location and sex affected the age precision estimates between two southern, reservoir populations of paddlefish [Polyodon spathula (Walbaum, 1792)]. From 589 paddlefish collected in Grand Lake and Keystone Lake, Oklahoma in 2011, ages from dentaries were estimated using three independent readers and...
Ecological regime shift drives declining growth rates of sea turtles throughout the West Atlantic
Karen A. Bjorndal, Alan B. Bolten, Milani Chaloupka, Vincent S. Saba, Claudio Bellini, Maria A.G. Marcovaldi, Armando J.B. Santos, Luis Felipe Wurdig Bortolon, Anne B. Meylan, Peter A. Meylan, Jennifer Gray, Robert Hardy, Beth Brost, Michael Bresette, Jonathan C. Gorham, Stephen Connett, Barbara Van Sciver Crouchley, Mike Dawson, Deborah Hayes, Carlos E. Diez, Robert P. van Dam, Sue Willis, Mabel Nava, Kristen M. Hart, Michael S. Cherkiss, Andrew Crowder, Clayton Pollock, Zandy Hillis-Starr, Fernando A. Munoz Teneria, Roberto Herrera-Pavon, Vanessa Labrada-Martagon, Armando Lorences, Ana Negrete-Philippe, Margaret M. Lamont, Allen M. Foley, Rhonda Bailey, Raymond R. Carthy, Russell Scarpino, Erin McMichael, Jane A. Provancha, Annabelle Brooks, Adriana Jardim, Milagros Lopez-Mendilaharsu, Daniel Gonzalez-Paredes, Andres Estrades, Alejandro Fallabrino, Gustavo Martinez-Souza, Gabriela M. Velez-Rubio, Ralf H. Boulon Jr., Jaime Collazo, Robert Wershoven, Vicente Guzman Hernandez, Thomas B. Stringell, Amdeep Sanghera, Peter B. Richardson, Annette C. Broderick, Quinton Phillips, Marta C. Calosso, John A.B. Claydon, Tasha L. Metz, Amanda L. Gordon, Andre M. Landry Jr., Donna J. Shaver, Janice Blumenthal, Lucy Collyer, Brendan J. Godley, Andrew McGowan, Matthew J. Witt, Cathi L. Campbell, Cynthia J. Lagueux, Thomas L. Bethel, Lory Kenyon
2017, Global Change Biology (23) 4556-4568
Somatic growth is an integrated, individual-based response to environmental conditions, especially in ectotherms. Growth dynamics of large, mobile animals are particularly useful as bio-indicators of environmental change at regional scales. We assembled growth rate data from throughout the West Atlantic for green turtles, Chelonia mydas, which are long-lived, highly migratory,...
High sensitivity of gross primary production in the Rocky Mountains to summer rain
M. Berkelhammer, I.C. Stefanescu, J. Joiner, Lesleigh Anderson
2017, Geophysical Research Letters (44) 3643-3652
In the catchments of the Rocky Mountains, peak snowpack is declining in response to warmer spring temperatures. To understand how this will influence terrestrial gross primary production (GPP), we compared precipitation data across the intermountain west with satellite retrievals of solar-induced fluorescence (SIF), a proxy for GPP. Annual precipitation patterns...
Seawater-flooding events and impact on freshwater lenses of low-lying islands: Controlling factors, basic management and mitigation
Stephen B. Gingerich, Clifford I. Voss, Adam G. Johnson
2017, Journal of Hydrology (551) 676-688
An unprecedented set of hydrologic observations was collected after the Dec 2008 seawater-flooding event on Roi-Namur, Kwajalein Atoll, Republic of the Marshall Islands. By two days after the seawater flooding that occurred at the beginning of dry season, the observed salinity of water withdrawn by the island’s main skimming...
Controls on the chemical composition of saline surface crusts and emitted dust from a wet playa in the Mojave Desert (USA)
Harland L. Goldstein, George N. Breit, Richard L. Reynolds
2017, Journal of Arid Environments (140) 50-66
Saline-surface crusts and their compositions at ephemeral, dry, and drying lakes are important products of arid-land processes. Detailed understanding is lacking, however, about interactions among locally variable hydrogeologic conditions, compositional control of groundwater on vadose zone and surface salts, and dust composition. Chemical and physical data from groundwater, sediments, and...
A practical method for the determination of total selenium in environmental samples using isotope dilution-hydride generation-inductively coupled plasma-mass spectrometry
Amy E. Kleckner, Evangelos Kakouros, A. Robin Stewart
2017, Limnology and Oceanography: Methods (15) 363-371
A safe, practical, and accurate method for the determination of selenium (Se) in range of environmental samples was developed. Small sample masses, 5–20 mg, were amended with 82Se enriched isotope for the isotope dilution (ID), preceding a multi-step wet digestion with nitric acid (HNO3) and hydrogen peroxide (H2O2). Samples were...
Using a full annual cycle model to evaluate long-term population viability of the conservation-reliant Kirtland's warbler after successful recovery
Donald J. Brown, Christine Ribic, Deahn M. Donner, Mark D. Nelson, Carol I. Bocetti, Christie M. Deloria-Sheffield
2017, Journal of Applied Ecology (54) 439-449
Long-term management planning for conservation-reliant migratory songbirds is particularly challenging because habitat quality in different stages and geographic locations of the annual cycle can have direct and carry-over effects that influence the population dynamics. The Neotropical migratory songbird Kirtland's warbler Setophaga kirtlandii (Baird 1852) is listed as...
Subsequent-year recaptures at winter sites in three species of shrubland sparrows (Emberizidae)
Steven T. Knick, Matthias Leu, Steve E. Hanser
2017, Southwestern Naturalist (62) 121-125
The tendency by individual birds to return to winter sites in subsequent years can be important in assessing the potential influence of habitat changes during the nonbreeding period. We recaptured five Brewer's (Spizella breweri), seven sagebrush (Artemisiospiza nevadensis), and three black-throated (Amphispiza bilineata) sparrows from 1–3 subsequent years at the...
Geologic map of Meridiani Planum, Mars
Brian M. Hynek, Gaetano Di Achille
2017, Scientific Investigations Map 3356
Introduction and BackgroundThe Meridiani Planum region of Mars—originally named due to its proximity to the Martian prime meridian—contains a variety of geologic units, including those that are crater‑related, that span the Early Noachian to Late Amazonian Epochs. Mars Global Surveyor (MGS) data indicate this area contains extensive layered deposits, some...
Precipitation thresholds for landslide occurrence near Seattle, Mukilteo, and Everett, Washington
Caroline R. Scheevel, Rex L. Baum, Benjamin B. Mirus, Joel B. Smith
2017, Open-File Report 2017-1039
Shallow landslides along coastal bluffs frequently occur in the railway corridor between Seattle and Everett, Washington. These slides disrupt passenger rail service, both because of required track maintenance and because the railroad owner, Burlington Northern Santa Fe Railway, does not allow passenger travel for 48 hours after a disruptive landslide....
Ongoing efforts to make ash-cloud model forecasts more accurate
Larry G. Mastin, Alexa R. Van Eaton, David J. Schneider, Roger P. Denlinger
2017, Conference Paper, Proceedings of impact of volcanic ash clouds on military operations
The 2010 eruption of Eyjafjallajökull volcano in Iceland changed the rules for air travel in Europe and introduced the use of restricted fly zones based on ash-cloud concentrations calculated by dispersion models. This change prompted a sustained effort to improve the accuracy of ash-cloud model forecasts. In this paper we...
Pore network modeling of the electrical signature of solute transport in dual-domain media
Frederick Day-Lewis, Niklas Linde, Roy Haggerty, Kamini Singha, Martin A. Briggs
2017, Geophysical Research Letters (44) 4908-4916
Dual-domain models are used to explain anomalous solute transport behavior observed in diverse hydrologic settings and applications, from groundwater remediation to hyporheic exchange. To constrain such models, new methods are needed with sensitivity to both immobile and mobile domains. Recent experiments indicate that dual-domain transport of ionic...