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Page 1207, results 30151 - 30175

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Wintering ecology of sympatric subspecies of Sandhill Crane: Correlations between body size, site fidelity, and movement patterns
Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, Joseph P. Fleskes
2015, The Condor (117) 518-529
Body size is known to correlate with many aspects of life history in birds, and this knowledge can be used to manage and conserve bird species. However, few studies have compared the wintering ecology of sympatric subspecies that vary significantly in body size. We used radiotelemetry to examine the relationship...
Nutrient-enhanced decomposition of plant biomass in a freshwater wetland
James E. Bodker, Robert Eugene Turner, Andrew Tweel, Christopher Schulz, Christopher M. Swarzenski
2015, Aquatic Botany (127) 44-52
We studied soil decomposition in a Panicum hemitomon (Schultes)-dominated freshwater marsh located in southeastern Louisiana that was unambiguously changed by secondarily-treated municipal wastewater effluent. We used four approaches to evaluate how belowground biomass decomposition rates vary under different nutrient regimes in this marsh. The results of laboratory experiments demonstrated how nutrient enrichment...
Now hiring! Empirically testing a three-step intervention to increase faculty gender diversity in STEM
Jessi L. Smith, Ian M. Handley, Alexander V. Zale, Sara Rushing, Martha A. Potvin
2015, BioScience (65) 1084-1087
Workforce homogeneity limits creativity, discovery, and job satisfaction; nonetheless, the vast majority of university faculty in science, technology, engineering, and mathematics (STEM) fields are men. We conducted a randomized and controlled three-step faculty search intervention based in self-determination theory aimed at increasing the number of women faculty in STEM at...
Dreissenid mussel research priorities workshop
Mark Sytsma, Stephen Phillips, Timothy D. Counihan
2015, Conference Paper, Center for Lakes and Reservoirs Publications and Presentations
Currently, dreissenid mussels have yet to be detected in the northwestern part of the United States and western Canada. Infestation of one of the jurisdictions within the mussel-free Pacific Northwest would likely have significant economic, soci­etal and environmental implications for the entire region. Understanding the biology and environmental tolerances of...
Interpretation of hydraulic conductivity in a fractured-rock aquifer over increasingly larger length dimensions
Allen M. Shapiro, Jeffery Ladderud, Richard M. Yager
2015, Hydrogeology Journal (23) 1319-1339
A comparison of the hydraulic conductivity over increasingly larger volumes of crystalline rock was conducted in the Piedmont physiographic region near Bethesda, Maryland, USA. Fluid-injection tests were conducted on intervals of boreholes isolating closely spaced fractures. Single-hole tests were conducted by pumping in open boreholes for approximately 30 min, and an...
Trends and natural variability of North American spring onset as evaluated by a new gridded dataset of spring indices
Toby R. Ault, Mark D. Schwartz, Raul Zurita-Milla, Jake F. Weltzin, Julio L. Betancourt
2015, Journal of Climate (28) 8363-8378
Climate change is expected to modify the timing of seasonal transitions this century, impacting wildlife migrations, ecosystem function, and agricultural activity. Tracking seasonal transitions in a consistent manner across space and through time requires indices that can be used for monitoring and managing biophysical and ecological systems during the coming...
Mineral resource of the month: Pumice and pumicite
Robert Crangle Jr.
2015, Earth (November 2015)
Pumice is an extrusive igneous volcanic rock formed through the rapid cooling of air-pocketed lava, which results in a low-density, high-porosity rock. Fine-grained pumice, or pumicite, is defined as minute grains, flakes, threads or shards of volcanic glass, with a size finer than 4 millimeters. ...
Decomposition of sea lamprey Petromyzon marinus carcasses: temperature effects, nutrient dynamics, and implications for stream food webs
Daniel M. Weaver, Stephen M. Coghlan Jr., Joseph D. Zydlewski, Robert S. Hogg, Michael Canton
2015, Hydrobiologia (760) 57-67
Anadromous fishes serve as vectors of marine-derived nutrients into freshwaters that are incorporated into aquatic and terrestrial food webs. Pacific salmonines Oncorhynchus spp. exemplify the importance of migratory fish as links between marine and freshwater systems; however, little attention has been given to sea lamprey (Petromyzon...
The Open Water Data Initiative: Water information for a thirsty nation
Alan Rea, Edward Clark, Angela Adams, William B. Samuels
2015, Water Resources Impact (17) 7-10
Initial efforts of the Open Water Data Initiative have focused on three use cases covering flooding, drought, and contaminant spill response, with a goal of identifying critical water data resources and making them more accessible. Significant progress has been made in the past year, although much remains to be done....
Horseshoe crab spawning activity in Delaware Bay, USA, after harvest reduction: A mixed-model analysis
David R. Smith, Timothy J. Robinson
2015, Estuaries and Coasts (38) 2345-2354
A Delaware Bay, USA, standardized survey of spawning horseshoe crabs, Limulus polyphemus, was carried out in 1999 − 2013 through a citizen science network. Previous trend analyses of the data were at the state (DE or NJ) or bay-wide levels. Here, an alternative mixed-model regression analysis was used to estimate...
Geochemistry and origin of metamorphosed mafic rocks from the Lower Paleozoic Moretown and Cram Hill Formations of North-Central Vermont: Delamination magmatism in the western New England appalachians
Raymond Coish, Jonathan Kim, Evan Twelker, Scott P. Zolkos, Gregory J. Walsh
2015, American Journal of Science (315) 809-845
The Moretown Formation, exposed as a north-trending unit that extends from northern Vermont to Connecticut, is located along a critical Appalachian litho-tectonic zone between the paleomargin of Laurentia and accreted oceanic terranes. Remnants of magmatic activity, in part preserved as metamorphosed mafic rocks in the Moretown Formation and the overlying...
The surface elevation table and marker horizon technique: A protocol for monitoring wetland elevation dynamics
James C. Lynch, Phillippe Hensel, Donald R. Cahoon
2015, Natural Resource Report NPS/NCBN/NRR—2015/1078
The National Park Service, in response to the growing evidence and awareness of the effects of climate change on federal lands, determined that monitoring wetland elevation change is a top priority in North Atlantic Coastal parks (Stevens et al, 2010). As a result, the NPS Northeast Coastal and Barrier Network...
Stable carbon isotope fractionation during bacterial acetylene fermentation: Potential for life detection in hydrocarbon-rich volatiles of icy planet(oid)s
Laurence Miller, Shaun Baesman, Ron Oremland
2015, Astrobiology (15) 977-986
We report the first study of stable carbon isotope fractionation during microbial fermentation of acetylene (C2H2) in sediments, sediment enrichments, and bacterial cultures. Kinetic isotope effects (KIEs) averaged 3.7 ± 0.5‰ for slurries prepared with sediment collected at an intertidal mudflat in San Francisco Bay and 2.7 ± 0.2‰ for a pure culture of Pelobacter sp....
LIMS for Lasers 2015 for achieving long-term accuracy and precision of δ2H, δ17O, and δ18O of waters using laser absorption spectrometry
Tyler B. Coplen, Leonard I Wassenaar
2015, Rapid Communications in Mass Spectrometry (29) 2122-2130
RationaleAlthough laser absorption spectrometry (LAS) instrumentation is easy to use, its incorporation into laboratory operations is not easy, owing to extensive offline manipulation of comma-separated-values files for outlier detection, between-sample memory correction, nonlinearity (δ-variation with water amount) correction, drift correction, normalization to VSMOW-SLAP scales, and difficulty in performing long-term QA/QC...
Photoreduction of Hg(II) and photodemethylation of methylmercury: the key role of thiol sites on dissolved organic matter
Jeffrey D. Jeremiason, Joshua C. Portner, George R. Aiken, Amber J. Hiranaka, Michelle T. Dvorak, Khuyen T. Tran, Douglas E. Latch
2015, Environmental Science: Processes and Impacts (17) 1892-1903
This study examined the kinetics of photoreduction of Hg(II) and photodemethylation of methylmercury (MeHg+) attached to, or in the presence of, dissolved organic matter (DOM). Both Hg(II) and MeHg+ are principally bound to reduced sulfur groups associated with DOM in many freshwater systems. We propose that a direct photolysis mechanism is...
Imaging the magmatic system of Mono Basin, California with magnetotellurics in three--dimensions
Jared R. Peacock, Margaret T. Mangan, Darcy McPhee, David A. Ponce
2015, Journal of Geophysical Research (120) 7273-7289
A three–dimensional (3D) electrical resistivity model of Mono Basin in eastern California unveils a complex subsurface filled with zones of partial melt, fluid–filled fracture networks, cold plutons, and regional faults. In 2013, 62 broadband magnetotelluric (MT) stations were collected in an array around southeastern Mono Basin from which a 3D...
Mercury in stream water at five Czech catchments across a Hg and S deposition gradient
Tomáš Navrátil, James B. Shanley, Jan Rohovec, Filip Oulehle, Pavel Kram, Sarka Matouskova, Miroslav Tesar, Maria Hojdová
2015, Journal of Geochemical Exploration (158) 201-211
The Czech Republic was heavily industrialized in the second half of the 20th century but the associated emissions of Hg and S from coal burning were significantly reduced since the 1990s. We studied dissolved (filtered) stream water mercury (Hg) and dissolved organic carbon (DOC) concentrations at five catchments with contrasting...
Growth responses of five desert plants as influenced by biological soil crusts from a temperate desert, China
Yuanming Zhang, Jayne Belnap
2015, Ecological Research (30) 1037-1045
In almost all dryland systems, biological soil crusts (biocrusts) coexist alongside herbaceous and woody vegetation, creating landscape mosaics of vegetated and biocrusted patches. Results from past studies on the interaction between biocrusts and vascular plants have been contradictory. In the Gurbantunggut desert, a large temperate desert in northwestern China, well-developed...
Earthquake rupture process recreated from a natural fault surface
Thomas E. Parsons, Diane L. Minasian
2015, Journal of Geophysical Research B: Solid Earth (120) 7852-7862
What exactly happens on the rupture surface as an earthquake nucleates, spreads, and stops? We cannot observe this directly, and models depend on assumptions about physical conditions and geometry at depth. We thus measure a natural fault surface and use its 3D coordinates to construct a replica at 0.1 m...
Fire activity as a function of fire–weather seasonal severity and antecedent climate across spatial scales in southern Europe and Pacific western USA
Itziar R. Urbieta, Gonzalo Zavala, Joaquin Bedia, Jose M. Gutierrez, Jesus San Miguel-Ayanz, Andrea Camia, Jon E. Keeley, Jose M. Moreno
2015, Environmental Research Letters (10)
Climate has a strong influence on fire activity, varying across time and space. We analyzed the relationships between fire–weather conditions during the main fire season and antecedent water-balance conditions and fires in two Mediterranean-type regions with contrasted management histories: five southern countries of the European Union (EUMED)(all fires); the Pacific...
Density of river otters (Lontra canadensis) in relation to energy development in the Green River Basin, Wyoming
B.L. Godwin, S.E. Albeke, H.L. Bergman, Annika W. Walters, M. Ben-David
2015, Science of the Total Environment (532) 780-790
Exploration and extraction of oil and natural gas have increased in recent years and are expected to expand in the future. Reduction in water quality from energy extraction may negatively affect water supply for agriculture and urban use within catchments as well as down river. We used non-invasive genetic techniques...
Trends in publications in fluvial geomorphology over two decades: A truly new era in the discipline owing to recent technological revolution?
Hervé Piégay, G. Mathias Kondolf, J. Toby Minear, Lise Vaudor
2015, Geomorphology (248) 489-500
Trends in the field of fluvial geomorphology have been reviewed by a number of authors, who have emphasized the dramatic change occuring in the field in the last two decades of the twentieth century, largely as a result of technological advances. Nevertheless, no prior authors have systematically compiled data on...
Effects and quantification of acid runoff from sulfide-bearing rock deposited during construction of Highway E18, Norway
Atle Hindar, D. Kirk Nordstrom
2015, Applied Geochemistry (62) 150-163
The Highway E18 between the cities of Grimstad and Kristiansand, southern Norway, constructed in the period 2006–2009, cuts through sulfide-bearing rock. The geology of this area is dominated by slowly-weathering gneiss and granites, and oxidation of fresh rock surfaces can result in acidification of surface water. Sulfide-containing rock waste from...