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Page 150, results 3726 - 3750

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Not all publications have extents, not all extents are completely accurate
The southern megalopolis: using the past to predict the future of urban sprawl in the Southeast U.S.
Adam Terando, Jennifer Costanza, Curtis Belyea, Robert R. Dunn, Alexa McKerrow, Jaime Collazo
2014, PLoS ONE (9)
The future health of ecosystems is arguably as dependent on urban sprawl as it is on human-caused climatic warming. Urban sprawl strongly impacts the urban ecosystems it creates and the natural and agro-ecosystems that it displaces and fragments. Here, we project urban sprawl changes for the next 50 years for...
Detecting well casing leaks in Bangladesh using a salt spiking method
M.O. Stahl, J.B. Ong, C.F. Harvey, C. D. Johnson, A.B.M. Badruzzaman, M.H. Tarek, A. VanGeen, J.A. Anderson, J. W. Lane
2014, Ground Water (52) 195-200
We apply fluid-replacement logging in arsenic-contaminated regions of Bangladesh using a low-cost, down-well fluid conductivity logging tool to detect leaks in the cased section of wells. The fluid-conductivity tool is designed for the developing world: it is lightweight and easily transportable, operable by one person, and can be built for...
Application of near-surface geophysics as part of a hydrologic study of a subsurface drip irrigation system along the Powder River floodplain near Arvada, Wyoming
James I. Sams, Garret Veloski, Bruce D. Smith, Burke J. Minsley, Mark A. Engle, Brian A. Lipinski, Richard W. Hammack, John W. Zupancic
2014, International Journal of Coal Geology (126) 128-139
Rapid development of coalbed natural gas (CBNG) production in the Powder River Basin (PRB) of Wyoming has occurred since 1997. National attention related to CBNG development has focused on produced water management, which is the single largest cost for on-shore domestic producers. Low-cost treatment technologies allow operators to reduce...
Accuracy of travel time distribution (TTD) models as affected by TTD complexity, observation errors, and model and tracer selection
Christopher T. Green, Yong Zhang, Bryant C. Jurgens, J. Jeffrey Starn, Matthew K. Landon
2014, Water Resources Research (50) 6191-6213
Analytical models of the travel time distribution (TTD) from a source area to a sample location are often used to estimate groundwater ages and solute concentration trends. The accuracies of these models are not well known for geologically complex aquifers. In this study, synthetic datasets were used to quantify the...
Temporal variation in fish mercury concentrations within lakes from the western Aleutian Archipelago, Alaska
Leah A. Kenney, Collin A. Eagles-Smith, Joshua T. Ackerman, Frank A. von Hippel
2014, PLoS ONE (9)
We assessed temporal variation in mercury (Hg) concentrations of threespine stickleback (Gasterosteus aculeatus) from Agattu Island, Aleutian Archipelago, Alaska. Total Hg concentrations in whole-bodied stickleback were measured at two-week intervals from two sites in each of two lakes from June 1 to August 10, 2011 during the time period when...
Demographic monitoring and population viability analysis of two rare beardtongues from the Uinta Basin
Rebecca M. McCaffery, Rita Reisor, Kathryn M. Irvine, Jessi Brunson
2014, Western North American Naturalist (74) 257-274
Energy development, in combination with other environmental stressors, poses a persistent threat to rare species endemic to energy-producing regions of the western United States. Demographic analyses of monitored populations can provide key information on the natural dynamics of threatened plant and animal populations and how these dynamics might be affected...
Mapping forest height in Alaska using GLAS, Landsat composites, and airborne LiDAR
Birgit Peterson, Kurtis Nelson
2014, Remote Sensing (6) 12409-12426
Vegetation structure, including forest canopy height, is an important input variable to fire behavior modeling systems for simulating wildfire behavior. As such, forest canopy height is one of a nationwide suite of products generated by the LANDFIRE program. In the past, LANDFIRE has relied on a combination of field observations...
High-frequency imaging of elastic contrast and contact area with implications for naturally observed changes in fault properties
Kohei Nagata, Brian D. Kilgore, Nicholas M. Beeler, Masao Nakatani
2014, Journal of Geophysical Research (119) 5855-5875
During localized slip of a laboratory fault we simultaneously measure the contact area and the dynamic fault normal elastic stiffness. One objective is to determine conditions where stiffness may be used to infer changes in area of contact during sliding on nontransparent fault surfaces. Slip speeds between 0.01 and 10...
Characterization of the porosity distribution in the upper part of the karst Biscayne aquifer using common offset ground penetrating radar, Everglades National Park, Florida
Gregory S. Mountain, Xavier Comas, Kevin J. Cunningham
2014, Journal of Hydrology (515) 223-236
The karst Biscayne aquifer is characterized by a heterogeneous spatial arrangement of porosity and hydraulic conductivity, making conceptualization difficult. The Biscayne aquifer is the primary source of drinking water for millions of people in south Florida; thus, information concerning the distribution of karst features that concentrate the groundwater flow...
Dynamic response to strike-slip tectonic control on the deposition and evolution of the Baranof Fan, Gulf of Alaska
Maureen A. L. Walton, Sean P. S. Gulick, Robert S. Reece, Ginger A. Barth, Gail L. Christeson, Harm J. VanAvendonk
2014, Geosphere (10) 680-691
The Baranof Fan is one of three large deep-sea fans in the Gulf of Alaska, and is a key component in understanding large-scale erosion and sedimentation patterns for southeast Alaska and western Canada. We integrate new and existing seismic reflection profiles to provide new constraints on the Baranof Fan area,...
Investigating the potential role of persistent organic pollutants in Hawaiian green sea turtle fibropapillomatosis
Jennifer M. Keller, George H. Balazs, Frances Nilsen, Marc Rice, Thierry M. Work, Brenda A. Jensen
2014, Environmental Science & Technology (48) 7807-7816
It has been hypothesized for decades that environmental pollutants may contribute to green sea turtle fibropapillomatosis (FP), possibly through immunosuppression leading to greater susceptibility to the herpesvirus, the putative causative agent of this tumor-forming disease. To address this question, we measured concentrations of 164 persistent organic pollutants (POPs) and halogenated...
Polar bears from space: Assessing satellite imagery as a tool to track Arctic wildlife
Seth P. Stapleton, Michelle A. LaRue, Nicolas Lecomte, Stephen N. Atkinson, David L. Garshelis, Claire Porter, Todd C. Atwood
2014, PLoS ONE (9) 1-7
Development of efficient techniques for monitoring wildlife is a priority in the Arctic, where the impacts of climate change are acute and remoteness and logistical constraints hinder access. We evaluated high resolution satellite imagery as a tool to track the distribution and abundance of polar bears. We examined satellite images...
High spatial resolution WorldView-2 imagery for mapping NDVI and its relationship to temporal urban landscape evapotranspiration factors
Hamideh Nouri, Simon Beecham, Sharolyn Anderson, Pamela Nagler
2014, Remote Sensing (6) 580-602
Evapotranspiration estimation has benefitted from recent advances in remote sensing and GIS techniques particularly in agricultural applications rather than urban environments. This paper explores the relationship between urban vegetation evapotranspiration (ET) and vegetation indices derived from newly-developed high spatial resolution WorldView-2 imagery. The study site was Veale Gardens in Adelaide,...
Effects of disturbance associated with seismic exploration for oil and gas reserves in coastal marshes
Rebecca J. Howard, Christopher J. Wells, Thomas C. Michot, Darren J. Johnson
2014, Environmental Management (54) 30-50
Anthropogenic disturbances in wetland ecosystems can alter the composition and structure of plant assemblages and affect system functions. Extensive oil and gas extraction has occurred in wetland habitats along the northern Gulf of Mexico coast since the early 1900s. Activities involved with three-dimensional (3D) seismic exploration for these resources cause...
Three-year growth response of young Douglas-fir to nitrogen, calcium, phosphorus, and blended fertilizers in Oregon and Washington
Douglas B. Mainwaring, Douglas A. Maguire, Steven S. Perakis
2014, Forest Ecology and Management (327) 178-188
Studies of nutrient limitation in Douglas-fir forests of the Pacific Northwest focus predominantly on nitrogen, yet many stands demonstrate negligible or even negative growth response to nitrogen fertilization. To understand what nutrients other than nitrogen may limit forest productivity in this region, we tested six fertilizer treatments for their ability...
Climate-driven effects of fire on winter habitat for caribou in the Alaskan-Yukon Arctic
David D. Gustine, Todd J. Brinkman, Michael A. Lindgren, Jennifer I. Schmidt, T. Scott Rupp, Layne G. Adams
2014, PLoS ONE (9)
Climatic warming has direct implications for fire-dominated disturbance patterns in northern ecosystems. A transforming wildfire regime is altering plant composition and successional patterns, thus affecting the distribution and potentially the abundance of large herbivores. Caribou (Rangifer tarandus) are an important subsistence resource for communities throughout the north and a species...
Movement-based estimation and visualization of space use in 3D for wildlife ecology and conservation
Jeff A. Tracey, James Sheppard, Jun Zhu, Fu-Wen Wei, Ronald R. Swaisgood, Robert N. Fisher
2014, PLoS ONE (9)
Advances in digital biotelemetry technologies are enabling the collection of bigger and more accurate data on the movements of free-ranging wildlife in space and time. Although many biotelemetry devices record 3D location data with x, y, and z coordinates from tracked animals, the third z coordinate is typically not integrated...
Methylmercury-induced changes in gene transcription associated with neuroendocrine disruption in largemouth bass (Micropterus salmoides)
Catherine A. Richter, Christopher J. Martyniuk, Mandy L. Annis, William G. Brumbaugh, Lia C. Chasar, Nancy D. Denslow, Donald E. Tillitt
2014, General and Comparative Endocrinology (203) 215-224
Methyl-mercury (MeHg) is a potent neuroendocrine disruptor that impairs reproductive processes in fish. The objectives of this study were to (1) characterize transcriptomic changes induced by MeHg exposure in the female largemouth bass (LMB) hypothalamus under controlled laboratory conditions, (2) investigate the health and reproductive impacts of MeHg exposure on...
Replacement cost valuation of Northern Pintail (Anas acuta) subsistence harvest in Arctic and sub-Arctic North America
Joshua H. Goldstein, Wayne E. Thogmartin, Kenneth J. Bagstad, James A. Dubovsky, Brady J. Mattsson, Darius J. Semmens, Laura López-Hoffman, James E. Diffendorfer
2014, Human Dimensions of Wildlife: An International Journal (19) 347-354
Migratory species provide economically beneficial ecosystem services to people throughout their range, yet often, information is lacking about the magnitude and spatial distribution of these benefits at regional scales. We conducted a case study for Northern Pintails (hereafter pintail) in which we quantified regional and sub-regional economic values of subsistence...
Experimental design and quality assurance: in situ fluorescence instrumentation
Robyn N. Conmy, Carlos E. Del Castillo, Bryan D. Downing, Robert F. Chen
2014, Book chapter, Aquatic organic matter fluorescence
Both instrument design and capabilities of fluorescence spectroscopy have greatly advanced over the last several decades. Advancements include solid-state excitation sources, integration of fiber optic technology, highly sensitive multichannel detectors, rapid-scan monochromators, sensitive spectral correction techniques, and improve data manipulation software (Christian et al., 1981, Lochmuller and Saavedra, 1986; Cabniss...
Screening native botanicals for bioactivity: an interdisciplinary approach
Anik Boudreau, Diana M. Cheng, Carmen Ruiz, David Ribnicky, Larry K. Allain, C. Ray Brassieur, D. Phil Turnipseed, William T. Cefalu, Z. Elizabeth Floyd
2014, Nutrition (30) S11-S16
Objective: Plant-based therapies have been used in medicine throughout recorded history. Information about the therapeutic properties of plants often can be found in local cultures as folk medicine is communicated from one generation to the next. The aim of this study was to identify native Louisiana plants from Creole folk...
Comparative responses to endocrine disrupting compounds in early life stages of Atlantic salmon, Salmo salar
Tara A. Duffy, Luke R. Iwanowicz, Stephen D. McCormick
2014, Aquatic Toxicology (152) 1-10
Atlantic salmon (Salmo salar) are endangered anadromous fish that may be exposed to feminizing endocrine disrupting compounds (EDCs) during early development, potentially altering physiological capacities, survival and fitness. To assess differential life stage sensitivity to common EDCs, we carried out short-term (four day) exposures using three doses each of 17α-ethinylestradiol...
Avian response to timber harvesting applied experimentally to manage Cerulean Warbler breeding populations
James Sheehan, Petra Bohall Wood, David A. Buehler, Patrick D. Keyser, Jeffrey L. Larkin, Amanda D. Rodewald, T. Bently Wigley, Than J. Boves, Gregory A. George, Marja H. Bakermans, Tiffany A. Beachy, Andrea Evans, Molly E. McDermott, Felicity L. Newell, Kelly A. Perkins, Matthew White
2014, Forest Ecology and Management (321) 5-18
Timber harvesting has been proposed as a management tool to enhance breeding habitat for the Cerulean Warbler (Setophaga cerulea), a declining Neotropical–Nearctic migratory songbird that nests in the canopy of mature eastern deciduous forests. To evaluate how this single-species management focus might fit within an ecologically based management approach for...
Scenario earthquake hazards for the Long Valley Caldera-Mono Lake area, east-central California (ver. 2.0, January 2018)
Rui Chen, David M. Branum, Chris J. Wills, David P. Hill
2014, Open-File Report 2014-1045
As part of the U.S. Geological Survey’s (USGS) multi-hazards project in the Long Valley Caldera-Mono Lake area, the California Geological Survey (CGS) developed several earthquake scenarios and evaluated potential seismic hazards, including ground shaking, surface fault rupture, liquefaction, and landslide hazards associated with these earthquake scenarios. The results of these...
Air-sea interactions during strong winter extratropical storms
Jill Nelson, Ruoying He, John C. Warner, John Bane
2014, Ocean Dynamics
A high-resolution, regional coupled atmosphere–ocean model is used to investigate strong air–sea interactions during a rapidly developing extratropical cyclone (ETC) off the east coast of the USA. In this two-way coupled system, surface momentum and heat fluxes derived from the Weather Research and Forecasting model and sea surface temperature (SST)...