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Page 1298, results 32426 - 32450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Initial soil respiration response to biomass harvesting and green-tree retention in aspen-dominated forests of the Great Lakes region
Valerie J. Kurth, John B. Bradford, Robert A. Slesak, Anthony W. D’Amato
2014, Forest Ecology and Management (328) 342-352
Contemporary forest management practices are increasingly designed to optimize novel objectives, such as maximizing biomass feedstocks and/or maintaining ecological legacies, but many uncertainties exist regarding how these practices influence forest carbon (C) cycling. We examined the responses of soil respiration (Rs) to biomass harvesting and green-tree retention in an effort...
Forest stand structure, productivity, and age mediate climatic effects on aspen decline
David M. Bell, John B. Bradford, William K. Lauenroth
2014, Ecology (95) 2040-2046
Because forest stand structure, age, and productivity can mediate the impacts of climate on quaking aspen (Populus tremuloides) mortality, ignoring stand-scale factors limits inference on the drivers of recent sudden aspen decline. Using the proportion of aspen trees that were dead as an index of recent mortality at 841 forest...
Continuous estimation of baseflow in snowmelt-dominated streams and rivers in the Upper Colorado River Basin: A chemical hydrograph separation approach
Matthew P. Miller, David D. Susong, Christopher L. Shope, Victor M. Heilweil, Bernard J. Stolp
2014, Water Resources Research (50) 6986-6999
Effective science-based management of water resources in large basins requires a qualitative understanding of hydrologic conditions and quantitative measures of the various components of the water budget, including difficult to measure components such as baseflow discharge to streams. Using widely available discharge and continuously collected specific conductance (SC) data, we...
Site fidelity and condition metrics suggest sequential habitat use by early juvenile snook
Adam B. Brame, Carole McIvor, Ernst B Peebles, David J. Hollander
2014, Marine Ecology Progress Series (509) 255-269
The common snook Centropomus undecimalis is an estuarine-dependent fish that relies on landward wetlands as nursery habitat. Despite its economic importance, portions of the snook's early life history are poorly understood. We compared habitat use of young-of-the-year (YOY) snook in 2 geomorphic mesohabitats (tidal pond and tidal creek) along an...
Rice methylmercury exposure and mitigation: a comprehensive review
Sarah E. Rothenberg, Lisamarie Windham-Myers, Joel E. Creswell
2014, Environmental Research (133) 407-423
Rice cultivation practices from field preparation to post-harvest transform rice paddies into hot spots for microbial mercury methylation, converting less-toxic inorganic mercury to more-toxic methylmercury, which is likely translocated to rice grain. This review includes 51 studies reporting rice total mercury and/or methylmercury concentrations, based on rice (Orzya sativa) cultivated...
Aquatic CAM photosynthesis: a brief history of its discovery
Jon E. Keeley
2014, Aquatic Botany (118) 38-44
Aquatic CAM (Crassulacean Acid Metabolism) photosynthesis was discovered while investigating an unrelated biochemical pathway concerned with anaerobic metabolism. George Bowes was a significant contributor to this project early in its infancy. Not only did he provide me with some valuable perspectives on peer review rejections, but by working with his...
A mass balance approach to investigating geochemical controls on secondary water quality impacts at a crude oil spill site near Bemidji, MN
Gene-Hua Crystal Ng, Barbara A. Bekins, Isabelle M. Cozzarelli, Mary Jo Baedecker, Philip C. Bennett, Richard T. Amos
2014, Journal of Contaminant Hydrology (164) 1-15
Secondary water quality impacts can result from a broad range of coupled reactions triggered by primary groundwater contaminants. Data from a crude-oil spill research site near Bemidji, MN provide an ideal test case for investigating the complex interactions controlling secondary impacts, including depleted dissolved oxygen and elevated organic carbon, inorganic...
Major element and oxygen isotope geochemistry of vapour-phase garnet from the Topopah Spring Tuff at Yucca Mountain, Nevada, USA
Richard J. Moscati, Craig A. Johnson
2014, Mineralogical Magazine (78) 1029-1041
Twenty vapour-phase garnets were studied in two samples of the Topopah Spring Tuff of the Paintbrush Group from Yucca Mountain, in southern Nevada. The Miocene-age Topopah Spring Tuff is a 350 m thick, devitrified, moderately to densely welded ash-flow tuff that is zoned compositionally from high-silica rhyolite to latite. During...
Improving tsunami resiliency: California's Tsunami Policy Working Group
Charles R. Real, Laurie Johnson, Lucile M. Jones, Stephanie L. Ross
Y.A. Kontar, V. Santiago-Fandino, T. Takahashi, editor(s)
2014, Book chapter, Tsunami events and lessons learned: environmental and societal significance
California has established a Tsunami Policy Working Group to facilitate development of policy recommendations for tsunami hazard mitigation. The Tsunami Policy Working Group brings together government and industry specialists from diverse fields including tsunami, seismic, and flood hazards, local and regional planning, structural engineering, natural hazard policy, and coastal engineering....
Preliminary geologic map of the eastern Willapa Hills, Cowlitz, Lewis, and Wahkiakum Counties, Washington
Ray E. Wells, Michael G. Sawlan
2014, Open-File Report 2014-1063
This digital map database and the PDF derived from the database were created from the analog geologic map: Wells, R.E. (1981), “Geologic map of the eastern Willapa Hills, Cowlitz, Lewis, and Wahkiakum Counties, Washington.” The geodatabase replicates the geologic mapping of the 1981 report with minor exceptions along water boundaries...
Time-averaged discharge rate of subaerial lava at Kīlauea Volcano, Hawai‘i, measured from TanDEM-X interferometry: Implications for magma supply and storage during 2011-2013
Michael P. Poland
2014, Journal of Geophysical Research B: Solid Earth (119) 5464-5481
Differencing digital elevation models (DEMs) derived from TerraSAR add-on for Digital Elevation Measurements (TanDEM-X) synthetic aperture radar imagery provides a measurement of elevation change over time. On the East Rift Zone (EZR) of Kīlauea Volcano, Hawai‘i, the effusion of lava causes changes in topography. When these elevation changes are summed...
Emplacement and erosive effects of the south Kasei Valles lava on Mars
Colin M. Dundas, Laszlo P. Keszthelyi
2014, Journal of Volcanology and Geothermal Research (282) 92-102
Although it has generally been accepted that the Martian outflow channels were carved by floods of water, observations of large channels on Venus and Mercury demonstrate that lava flows can cause substantial erosion. Recent observations of large lava flows within outflow channels on Mars have revived discussion of the hypothesis...
A hierarchical integrated population model for greater sage-grouse (Centrocercus urophasianus) in the Bi-State Distinct Population Segment, California and Nevada
Peter S. Coates, Brian J. Halstead, Erik J. Blomberg, Brianne Brussee, Kristy B. Howe, Lief Wiechman, Joel Tebbenkamp, Kerry P. Reese, Scott C. Gardner, Michael L. Casazza
2014, Open-File Report 2014-1165
Greater sage-grouse (Centrocercus urophasianus, hereafter referred to as “sage-grouse”) are endemic to sagebrush (Artemisia spp.) ecosystems throughout Western North America. Populations of sage-grouse have declined in distribution and abundance across the range of the species (Schroeder and others, 2004; Knick and Connelly, 2011), largely as a result of human disruption...
Spatially explicit modeling of greater sage-grouse (Centrocercus urophasianus) habitat in Nevada and northeastern California: a decision-support tool for management
Peter S. Coates, Michael L. Casazza, Brianne E. Brussee, Mark A. Ricca, K. Benjamin Gustafson, Cory T. Overton, Erika Sanchez-Chopitea, Travis Kroger, Kimberly Mauch, Lara Niell, Kristy Howe, Scott Gardner, Shawn Espinosa, David J. Delehanty
2014, Open-File Report 2014-1163
Greater sage-grouse (Centrocercus urophasianus, hereafter referred to as “sage-grouse”) populations are declining throughout the sagebrush (Artemisia spp.) ecosystem, including millions of acres of potential habitat across the West. Habitat maps derived from empirical data are needed given impending listing decisions that will affect both sage-grouse population dynamics and human land-use...
Causal networks clarify productivity-richness interrelations, bivariate plots do not
James B. Grace, Peter B. Adler, W. Stanley Harpole, Elizabeth T. Borer, Eric W. Seabloom
2014, Functional Ecology (28) 787-798
Perhaps no other pair of variables in ecology has generated as much discussion as species richness and ecosystem productivity, as illustrated by the reactions by Pierce (2013) and others to Adler et al.'s (2011) report that empirical patterns are weak and inconsistent. Adler et al. (2011) argued we need to...
Raman spectroscopic characterization of CH4 density over a wide range of temperature and pressure
Linbo Shang, I-Ming Chou, Robert Burruss, Ruizhong Hu, Xianwu Bi
2014, Journal of Raman Spectroscopy (45) 696-702
The positions of the CH4 Raman ν1 symmetric stretching bands were measured in a wide range of temperature (from −180 °C to 350 °C) and density (up to 0.45 g/cm3) using high-pressure optical cell and fused silica capillary capsule. The results show that the Raman band shift is a function of both methane density and...
The implications of microbial and substrate limitation for the fates of carbon in different organic soil horizon types of boreal forest ecosystems: a mechanistically based model analysis
Y. He, Q. Zhuang, Jennifer W. Harden, A. David McGuire, Z. Fan, Y. Liu, Kimberly P. Wickland
2014, Biogeosciences (11) 4477-4491
The large amount of soil carbon in boreal forest ecosystems has the potential to influence the climate system if released in large quantities in response to warming. Thus, there is a need to better understand and represent the environmental sensitivity of soil carbon decomposition. Most soil carbon decomposition models...
Dissolved organic carbon concentration controls benthic primary production: results from in situ chambers in north-temperate lakes
Sean C. Godwin, Stuart E. Jones, Brian Weidel, Christopher T. Solomon
2014, Limnology and Oceanography (59) 2112-2120
We evaluated several potential drivers of primary production by benthic algae (periphyton) in north-temperate lakes. We used continuous dissolved oxygen measurements from in situ benthic chambers to quantify primary production by periphyton at multiple depths across 11 lakes encompassing a broad range of dissolved organic carbon (DOC) and total phosphorous...
A depth-averaged debris-flow model that includes the effects of evolving dilatancy. I. Physical basis
Richard M. Iverson, David L. George
2014, Proceedings of the Royal Society A (471)
To simulate debris-flow behaviour from initiation to deposition, we derive a depth-averaged, two-phase model that combines concepts of critical-state soil mechanics, grain-flow mechanics and fluid mechanics. The model's balance equations describe coupled evolution of the solid volume fraction, m, basal pore-fluid pressure, flow thickness and two...
The geology and geochemistry of Isla Floreana, Galápagos: A different type of late-stage ocean island volcanism
Karen S. Harpp, Dennis J. Geist, Alison M. Koleszar, Branden Christensen, John J. Lyons, Melissa Sabga, Nathan Rollins
Karen S. Harpp, Eric Mittelstaedt, Noemi d’Ozouville, David W. Graham, editor(s)
2014, Book chapter, The Galápagos: A natural laboratory for the earth sciences
Isla Floreana, the southernmost volcano in the Galápagos Archipelago, has erupted a diverse suite of alkaline basalts continually since 1.5 Ma. Because these basalts have different compositions than xenoliths and older lavas from the deep submarine sector of the volcano, Floreana is interpreted as being in a rejuvenescent or late-stage phase...
Petrographic maturity parameters of a Devonian shale maturation series, Appalachian Basin, USA. ICCP Thermal Indices Working Group interlaboratory exercise
Carla Viviane Araujo, Angeles G. Borrego, Brian Cardott, Renata Brenand A. das Chagas, Deolinda Flores, Paula Goncalves, Paul C. Hackley, James C. Hower, Marcio Luciano Kern, Jolanta Kus, Maria Mastalerz, Joao Graciano Mendonca Filho, Joalice de Oliveira Mendonca, Taissa Rego Menezes, Jane Newman, Isabel Suarez-Ruiz, Frederico Sobrinho da Silva, Igor Viegas de Souza
2014, International Journal of Coal Geology (130) 89-101
This paper presents results of an interlaboratory exercise on organic matter optical maturity parameters using a natural maturation series comprised by three Devonian shale samples (Huron Member, Ohio Shale) from the Appalachian Basin, USA. This work was conducted by the Thermal Indices Working Group of the International Committee for...
Bile salts as semiochemicals in fish
Tyler J. Buchinger, Weiming Li, Nicholas S. Johnson
2014, Chemical Senses (39) 647-654
Bile salts are potent olfactory stimuli in fishes; however the biological functions driving such sensitivity remain poorly understood. We provide an integrative review of bile salts as semiochemicals in fish. First, we present characteristics of bile salt structure, metabolism, and function that are particularly relevant to chemical communication. Bile salts...
Modeling future scenarios of light attenuation and potential seagrass success in a eutrophic estuary
Pilar del Barrio, Neil K. Ganju, Alfredo L. Aretxabaleta, Melanie Hayn, Andres Garcia, Robert W. Howarth
2014, Estuarine, Coastal and Shelf Science (149) 13-23
Estuarine eutrophication has led to numerous ecological changes, including loss of seagrass beds. One potential cause of these losses is a reduction in light availability due to increased attenuation by phytoplankton. Future sea level rise will also tend to reduce light penetration and modify seagrass habitat. In the present study,...
Pharmacokinetics of buprenorphine hydrochloride following intramuscular and intravenous administration to American kestrels (Falco sparverius)
Kate A. Gustavsen, David Sanchez-Migallon Guzman, Heather K. Knych, Olivia A. Petritz, Glenn H. Olsen, Joanne R. Paul-Murphy
2014, American Journal of Veterinary Research (75) 711-715
Objective—To determine the pharmacokinetics of buprenorphine hydrochloride after IM and IV administration to American kestrels (Falco sparverius). Animals—13 healthy 3-year-old captive-bred American kestrels. Procedures—Buprenorphine hydrochloride (0.6 mg/kg) was administered IM to all birds. Blood samples were collected at 9 times, ranging from 5 minutes to 9 hours after drug administration. Plasma...