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Page 143, results 3551 - 3575

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Ground-based thermal imaging of stream surface temperatures: Technique and evaluation
Scott A. Bonar, Sally J. Petre
2015, North American Journal of Fisheries Management (35) 1209-1218
We evaluated a ground-based handheld thermal imaging system for measuring water temperatures using data from eight southwestern USA streams and rivers. We found handheld thermal imagers could provide considerably more spatial information on water temperature (for our unit one image = 19,600 individual temperature measurements) than traditional methods could supply...
Early Permian conodont fauna and stratigraphy of the Garden Valley Formation, Eureka County, Nevada
Bruce R. Wardlaw, Dora M. Gallegos, Valery V. Chernykh, Walter S. Snyder
2015, Micropaleontology (61) 369-387
The lower part of the Garden Valley Formation yields two distinct conodont faunas. One of late Asselian age dominated by Mesogondolella and Streptognathodus and one of Artinskian age dominated by Sweetognathus with Mesogondolella. The Asselian fauna contains the same species as those found in the type area of the Asselian...
Uranium Sequestration During Biostimulated Reduction and In Response to the Return of Oxic Conditions In Shallow Aquifers
Christopher C. Fuller, Kelly J. Johnson, Katherine Akstin, David M. Singer, Steven B. Yabusaki, Yi Fang, M. Fuhrmann
2015, Report
A proposed approach for groundwater remediation of uranium contamination is to generate reducing conditions by stimulating the growth of microbial populations through injection of electron donor compounds into the subsurface. Sufficiently reducing conditions will result in reduction of soluble hexavalent uranium, U(VI), and precipitation of the less soluble +4 oxidation...
Tracing historical trends of Hg in the Mississippi River using Hg concentrations and Hg isotopic compositions in a lake sediment core, Lake Whittington, Mississippi, USA
John E. Gray, Peter C. Van Metre, Michael J. Pribil, Arthur J. Horowitz
2015, Chemical Geology (395) 80-87
Concentrations and isotopic compositions of mercury (Hg) in a sediment core collected from Lake Whittington, an oxbow lake on the Lower Mississippi River, were used to evaluate historical sources of Hg in the Mississippi River basin. Sediment Hg concentrations in the Lake Whittington core have a large 10-15 y peak...
Sensitivity of tsunami evacuation modeling to direction and land cover assumptions
Mathew C. Schmidtlein, Nathan J. Wood
2015, Applied Geography (56) 154-163
Although anisotropic least-cost-distance (LCD) modeling is becoming a common tool for estimating pedestrian-evacuation travel times out of tsunami hazard zones, there has been insufficient attention paid to understanding model sensitivity behind the estimates. To support tsunami risk-reduction planning, we explore two aspects of LCD modeling as it applies to pedestrian...
The role of tidal marsh restoration in fish management in the San Francisco Estuary
Bruce Herbold, Donald Baltz, Larry R. Brown, Robin Grossinger, Wim J. Kimmerer, Peggy W. Lehman, Charles A. Simenstad, Carl Wilcox, Matthew L. Nobriga
2015, San Francisco Estuary and Watershed Science (12)
Tidal marsh restoration is an important management issue in the San Francisco Estuary (estuary). Restoration of large areas of tidal marsh is ongoing or planned in the lower estuary (up to 6,000 ha, Callaway et al. 2011). Large areas are proposed for restoration in the upper estuary under the Endangered...
BET surface area distributions in polar stream sediments: Implications for silicate weathering in a cold-arid environment
Kristen R. Marra, Megan E Elwood Madden, Gerilyn S. Soreghan, Brenda L Hall
2015, Applied Geochemistry (52) 31-42
BET surface area values are critical for quantifying the amount of potentially reactive sediments available for chemical weathering and ultimately, prediction of silicate weathering fluxes. BET surface area values of fine-grained (<62.5 μm) sediment from the hyporheic zone of polar glacial streams in the McMurdo Dry Valleys, Antarctica (Wright and...
Vegetation controls on weathering intensity during the last deglacial transition in southeast Africa
Sarah J. Ivory, Michael M. McGlue, Geoffrey S. Ellis, Anne-Marie Lézine, Andrew S. Cohen, Annie Vincens
2015, PLoS ONE (9)
Tropical climate is rapidly changing, but the effects of these changes on the geosphere are unknown, despite a likelihood of climatically-induced changes on weathering and erosion. The lack of long, continuous paleo-records prevents an examination of terrestrial responses to climate change with sufficient detail to answer questions about how systems...
Cyclic avian mass mortality in the northeastern United States is associated with a novel orthomyxovirus
Andrew B. Allison, Jennifer R. Ballard, Robert B. Tesh, Justin D. Brown, Mark G. Ruder, M. Kevin Keel, Brandon A. Munk, Randall M. Mickley, Samantha E.J. Gibbs, Julie C. Ellis, Amelia P.A. Travassos da Rosac, S. Ip, Valerie I. Shearn-Bochsler, Matthew B. Rogers, Elodie Gheldin, Edward C. Holmes, Colin R. Parrish, Chris P. Dwyer
2015, Journal of Virology (89) 1389-1403
Since 1998, cyclic mortality events in common eiders (Somateria mollissima), numbering in the hundreds to thousands of dead birds, have been documented along the coast of Cape Cod, Massachusetts, USA. Although longitudinal disease investigations have uncovered potential contributing factors responsible for these outbreaks, detecting a primary etiological agent has proven...
MODFLOW-based coupled surface water routing and groundwater-flow simulation
Joseph D. Hughes, Christian D. Langevin, Jeremy T. White
2015, Groundwater (53) 452-463
In this paper, we present a flexible approach for simulating one- and two-dimensional routing of surface water using a numerical surface water routing (SWR) code implicitly coupled to the groundwater-flow process in MODFLOW. Surface water routing in SWR can be simulated using a diffusive-wave approximation of the Saint-Venant equations and/or...
Dietary mercury exposure to endangered California Clapper Rails in San Francisco Bay
Michael L. Casazza, Mark A. Ricca, Cory T. Overton, John Y. Takekawa, Angela Merritt, Joshua T. Ackerman
2015, Marine Pollution Bulletin (86) 254-260
California Clapper Rails (Rallus longirostris obsoletus) are an endangered waterbird that forage in tidal-marsh habitats that pose risks from mercury exposure. We analyzed total mercury (Hg) in six macro-invertebrate and one fish species representing Clapper Rail diets from four tidal-marshes in San Francisco Bay, California. Mercury concentrations among individual taxa...
Predicted effects of future climate warming on thermal habitat suitability for Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) in rivers in Wisconsin, USA
John D. Lyons, Jana S. Stewart
2015, Journal of Applied Ichthyology (30) 1508-1513
The Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) may be threatened by future climate warming. The purpose of this study was to identify river reaches in Wisconsin, USA, where they might be vulnerable to warming water temperatures. In Wisconsin, A. fulvescens is known from 2291 km of large-river habitat that has...
Please don't misuse the museum: 'declines' may be statistical
Evan H. Campbell Grant
2015, Global Change Biology (21) 1018-1024
Detecting declines in populations at broad spatial scales takes enormous effort, and long-term data are often more sparse than is desired for estimating trends, identifying drivers for population changes, framing conservation decisions or taking management actions. Museum records and historic data can be available at large scales across multiple decades,...
Contrasting long-term survival of two outplanted Mojave Desert perennials for post-fire revegetation
Sara J. Scoles-Sciulla, Lesley A. Defalco, Todd C. Esque
2015, Arid Land Research and Management (29) 110-124
Post-fire recovery of arid shrublands is typically slow, and planting greenhouse-raised seedlings may be a means of jump-starting this process. Recovery can be further accelerated by understanding the factors controlling post-planting survival. In fall 2007 and 2009, we outplanted seedlings of two contrasting native evergreen shrubs—fast-growing Nevada jointfir and slow-growing...
High-resolution paleoclimatology of the Santa Barbara Basin during the Medieval Climate Anomaly and early Little Ice Age based on diatom and silicoflagellate assemblages in Kasten core SPR0901-02KC
John A. Barron, David B. Bukry, Ingrid L. Hendy
2015, Quaternary International (387) 13-22
Diatom and silicoflagellate assemblages documented in a high-resolution time series spanning 800 to 1600 AD in varved sediment recovered in Kasten core SPR0901-02KC (34°16.845’ N, 120°02.332’ W, water depth 588 m) from the Santa Barbara Basin (SBB) reveal that SBB surface water conditions during the Medieval Climate Anomaly (MCA) and...
Projected risk of population declines for native fish species in the Upper Mississippi River
S.M. Crimmins, P. Boma, W.E. Thogmartin
2015, River Research and Applications (31) 135-142
Conservationists are in need of objective metrics for prioritizing the management of habitats. For individual species, the threat of extinction is often used to prioritize what species are in need of conservation action. Using long-term monitoring data, we applied a Bayesian diffusion approximation to estimate quasi-extinction risk for 54 native...
USGS46 Greenland ice core water – A new isotopic reference material for δ2H and δ18O measurements of water
Tyler B. Coplen, Haiping Qi, Lauren V. Tarbox, Jennifer M. Lorenz, Bryan Buck
2015, Geostandards and Geoanalytical Research (38) 153-157
Ice core from Greenland was melted, filtered, homogenised, loaded into glass ampoules, sealed, autoclaved to eliminate biological activity, and calibrated by dual-inlet isotope-ratio mass spectrometry. This isotopic reference material (RM), USGS46, is intended as one of two secondary isotopic reference waters for daily normalisation of stable hydrogen (δ2H) and stable...
Sequence stratigraphic framework of upper pliocene to holocene sediments of the Los Angeles Basin, California: Implications for aquifer architecture
Kenneth D. Ehman, Brian D. Edwards, Daniel J. Ponti
2015, Book
Executive Summary Groundwater provides more than one-third of the municipal water supply for the coastal Los Angeles Basin and defining the aquifer architecture is a high priority for ground-water managers. Sequence stratigraphy, the state-of-the-art method for delineating reservoir geometry and continuity in the petroleum industry, is now being incorporated into ground water...
Forecasting the combined effects of urbanization and climate change on stream ecosystems: from impacts to management options
Karen C. Nelson, Margaret A. Palmer, James E. Pizzuto, Glenn E. Moglen, Paul L. Angermeier, Robert H. Hilderbrand, Mike Dettinger, Katharine Hayhoe
2015, Journal of Applied Ecology (46) 154-163
Streams collect runoff, heat, and sediment from their watersheds, making them highly vulnerable to anthropogenic disturbances such as urbanization and climate change. Forecasting the effects of these disturbances using process-based models is critical to identifying the form and magnitude of likely impacts. Here, we integrate a new biotic model with...
Laboratory constraints on models of earthquake recurrence
Nicholas M. Beeler, Terry Tullis, Jenni Junger, Brian D. Kilgore, David L. Goldsby
2014, Journal of Geophysical Research (119) 8770-8791
In this study, rock friction ‘stick-slip’ experiments are used to develop constraints on models of earthquake recurrence. Constant-rate loading of bare rock surfaces in high quality experiments produces stick-slip recurrence that is periodic at least to second order. When the loading rate is varied, recurrence is approximately inversely proportional to...
Response to L. Land comment on Bricker, Rice, Bricker (2014) From Headwaters to Coast: Influence of human activities on water quality of the Potomac River Estuary. Aquatic Geochemistry 20: 291-324
Suzanne B. Bricker, Karen C. Rice, III Owen Bricker Owen, P.
2014, Aquatic Geochemistry (20) 459-463
Overabundance of nutrients is considered one of the top challenges to most populated coastal water bodies, including Chesapeake Bay (Executive Order 13508). As scientists, one of our responsibilities is to contribute to the discussion and evaluation of management actions that have the potential to decrease pollution with concomitant improvement of...
Reduced disease in black abalone following mass mortality: Phage therapy and natural selection
Glenn R. VanBlaricom
2014, Frontiers in Microbiology (5) 10
Black abalone, Haliotis cracherodii, populations along the NE Pacific ocean have declined due to the rickettsial disease withering syndrome (WS). Natural recovery on San Nicolas Island (SNI) of Southern California suggested the development of resistance in island populations. Experimental challenges in one treatment demonstrated that progeny of disease-selected black abalone from...
Survival and reproduction of myxobolus cerebralis-resistant Rainbow Trout introduced to the colorado river and increased resistance of age-0 progeny
Dana L. Winkelman, Eric R. Fetherman, Melinda R. Baerwald, George J. Schisler
2014, PLoS ONE
Myxobolus cerebralis caused severe declines in rainbow trout populations across Colorado following its introduction in the 1980s. One promising approach for the recovery of Colorado’s rainbow trout populations has been the production of rainbow trout that are genetically resistant to the parasite. We introduced one of these resistant crosses, known as...
When to be discrete: The importance of time formulation in understanding animal movement
Brett T. McClintock, Devin S. Johnson, Mevin Hooten, Jay M. Ver Hoef, Juan M. Morales
2014, Movement Ecology (2)
Animal movement is essential to our understanding of population dynamics, animal behavior, and the impacts of global change. Coupled with high-resolution biotelemetry data, exciting new inferences about animal movement have been facilitated by various specifications of contemporary models. These approaches differ, but most share common themes. One key distinction is...
Ancient fish and recent invaders: white sturgeon Acipenser transmontanus diet response to invasive-species-mediated changes in a benthic prey assemblage
Steven C Zeug, Annie Brodsky, Nina Kogut, A. Robin Stewart, Joe Merz
2014, Marine Ecology Progress Series (514) 163-174
Invasive organisms can have significant impacts on native species, and the San Francisco Estuary (SFE), California, USA, is one of the world's most invaded estuaries. Decline of native white sturgeon Acipenser transmontanus abundance in the SFE has been acknowledged, but underlying mechanisms are poorly understood. Invasion by the overbite clam...