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Page 1758, results 43926 - 43950

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Publication Extents

Not all publications have extents, not all extents are completely accurate
The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: Implications for post-thaw carbon loss
J. A. O'Donnell, J.W. Harden, A. D. McGuire, M.Z. Kanevskiy, M.T. Jorgenson, X. Xu
2011, Global Change Biology (17) 1461-1474
High‐latitude regions store large amounts of organic carbon (OC) in active‐layer soils and permafrost, accounting for nearly half of the global belowground OC pool. In the boreal region, recent warming has promoted changes in the fire regime, which may exacerbate rates of permafrost thaw and alter soil OC dynamics in...
Deep long-period earthquakes beneath Washington and Oregon volcanoes
M.L. Nichols, S. D. Malone, Seth C. Moran, Weston A. Thelen, J.E. Vidale
2011, Journal of Volcanology and Geothermal Research (200) 116-128
Deep long-period (DLP) earthquakes are an enigmatic type of seismicity occurring near or beneath volcanoes. They are commonly associated with the presence of magma, and found in some cases to correlate with eruptive activity. To more thoroughly understand and characterize DLP occurrence near volcanoes in Washington and Oregon, we systematically...
Position of the Triassic-Jurassic boundary and timing of the end-Triassic extinctions on land: Data from the Moenave Formation on the southern Colorado Plateau, USA
S. G. Lucas, L.H. Tanner, L. Donohoo-Hurley, J. W. Geissman, H. W. Kozur, A.B. Heckert, Robert E. Weems
2011, Palaeogeography, Palaeoclimatology, Palaeoecology (302) 194-205
Strata of the Moenave Formation on and adjacent to the southern Colorado Plateau in Utah–Arizona, U.S.A., represent one of the best known and most stratigraphically continuous, complete and fossiliferous terrestrial sections across the Triassic–Jurassic boundary. We present a synthesis of new biostratigraphic and magnetostratigraphic data collected from across the Moenave...
Aeolian nutrient fluxes following wildfire in sagebrush steppe: Implications for soil carbon storage
N.J. Hasselquist, M.J. Germino, Joel B. Sankey, L.J. Ingram, N.F. Glenn
2011, Biogeosciences Discussions (8) 8323-8349
. Pulses of aeolian transport following fire can profoundly affect the biogeochemical cycling of nutrients in semi-arid and arid ecosystems. Our objective was to determine horizontal nutrient fluxes occurring in the saltation zone during an episodic pulse of aeolian transport that occurred following a wildfire in a semi-arid sagebrush steppe...
A bacterium that can grow by using arsenic instead of phosphorus
Felisa Wolfe-Simon, Jodi S. Blum, T.R. Kulp, Gordon W. Rattray, S.E. Hoeft, J. Pett-Ridge, J.F. Stolz, S.M. Webb, P.K. Weber, P.C.W. Davies, A.D. Anbar, R.S. Oremland
2011, Science (332) 1163-1166
Life is mostly composed of the elements carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus. Although these six elements make up nucleic acids, proteins, and lipids and thus the bulk of living matter, it is theoretically possible that some other elements in the periodic table could serve the same functions. Here,...
Canine detection of free-ranging brown treesnakes on Guam
Julie A. Savidge, James W. Stanford, Robert Reed, Ginger R. Haddock, Amy A. Yackel Adams
2011, New Zealand Journal of Ecology (35) 174-181
We investigated canine teams (dogs and their handlers) on Guam as a potential tool for finding invasive brown treesnakes (Boiga irregularis) in the wild. Canine teams searched a 40 × 40 m forested area for a snake that had consumed a dead mouse containing a radio-transmitter. To avoid tainting the...
Early growth of Kohala volcano and formation of long Hawaiian rift zones
Peter W. Lipman, Andrew T. Calvert
2011, Geology (39) 659-662
Transitional-composition pillow basalts from the toe of the Hilo Ridge, collected from outcrop by submersible, have yielded the oldest ages known from the Island of Hawaii: 1138 ± 34 to 1159 ± 33 ka. Hilo Ridge has long been interpreted as a submarine rift zone of Mauna Kea, but the...
Habitat selection and overlap of Atlantic salmon and smallmouth bass juveniles in nursery streams
G. Wathen, S.M. Coghlan Jr., Joseph D. Zydlewski, J.G. Trial
2011, Transactions of the American Fisheries Society (140) 1145-1157
Introduced smallmouth bass Micropterus dolomieu have invaded much of the historic freshwater habitat of Atlantic salmon Salmo salar in North America, yet little is known about the ecological interactions between the two species. We investigated the possibility of competition for habitat between age-0 Atlantic salmon and age-0 and age-1 smallmouth bass by means of...
Raman spectroscopic measurements of CO2 density: Experimental calibration with high-pressure optical cell (HPOC) and fused silica capillary capsule (FSCC) with application to fluid inclusion observations
X. Wang, I-Ming Chou, W. Hu, Robert Burruss, Q. Sun, Y. Song
2011, Geochimica et Cosmochimica Acta (75) 4080-4093
Raman spectroscopy is a powerful method for the determination of CO2 densities in fluid inclusions, especially for those with small size and/or low fluid density. The relationship between CO2 Fermi diad split (Δ, cm−1) and CO2 density (ρ, g/cm3) has been documented by several previous studies. However, significant discrepancies exist among these...
Sibship reconstruction for inferring mating systems, dispersal and effective population size in headwater brook trout (Salvelinus fontinalis) populations
Yoichiro Kanno, Jason C. Vokoun, Benjamin H. Letcher
2011, Conservation Genetics (12) 619-628
Brook trout Salvelinus fontinalis populations have declined in much of the native range in eastern North America and populations are typically relegated to small headwater streams in Connecticut, USA. We used sibship reconstruction to infer mating systems, dispersal and effective population size of resident (non-anadromous) brook trout in two...
What is the role of fresh groundwater and recirculated seawater in conveying nutrients to the coastal ocean?
Yishai Weinstein, Yoseph Yechieli, Yehuda Shalem, William C. Burnett, Peter W. Swarzenski, Barak Herut
2011, Environmental Science and Technology (45) 5195-5200
Submarine groundwater discharge (SGD) is a major process operating at the land-sea interface. Quantifying the SGD nutrient loads and the marine/terrestrial controls of this transport is of high importance, especially in oligotrophic seas such as the eastern Mediterranean. The fluxes of nutrients in groundwater discharging from the seafloor at Dor...
Spatial modeling for groundwater arsenic levels in North Carolina
D. Kim, M.L. Miranda, J. Tootoo, P. Bradley, A.E. Gelfand
2011, Environmental Science & Technology (45) 4824-4831
To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized...
Whole-edifice ice volume change A.D. 1970 to 2007/2008 at Mount Rainier, Washington, based on LiDAR surveying
T. W. Sisson, J.E. Robinson, D.D. Swinney
2011, Geology (39) 639-642
Net changes in thickness and volume of glacial ice and perennial snow at Mount Rainier, Washington State, have been mapped over the entire edifice by differencing between a highresolution LiDAR (light detection and ranging) topographic survey of September-October 2007/2008 and the 10 m lateral resolution U.S. Geological Survey digital elevation...
Fish community and bioassessment responses to stream network position
N.P. Hitt, P. L. Angermeier
2011, Journal of the North American Benthological Society (30) 296-309
If organisms move beyond the boundaries of local sampling units, regional metacommunity dynamics could undermine the ability of bioassessment studies to characterize local environmental quality. We tested the prediction that fish dispersal influences local fish community structure and bioassessment metrics as a function of site position within stream networks. We...
Inter-specific coral chimerism: Genetically distinct multicellular structures associated with tissue loss in Montipora capitata
Thierry M. Work, Zac H. Forsman, Zoltan Szabo, Teresa D. Lewis, Greta S. Aeby, Robert J. Toonen
2011, PLoS ONE (6)
Montipora white syndrome (MWS) results in tissue-loss that is often lethal to Montipora capitata, a major reef building coral that is abundant and dominant in the Hawai'ian Archipelago. Within some MWS-affected colonies in Kane'ohe Bay, Oahu, Hawai'i, we saw unusual motile multicellular structures within gastrovascular canals (hereafter referred to as invasive gastrovascular...
Using normalized difference vegetation index to estimate carbon fluxes from small rotationally grazed pastures
R.H. Skinner, B.K. Wylie, T.G. Gilmanov
2011, Agronomy Journal (103) 972-979
Satellite-based normalized difference vegetation index (NDVI) data have been extensively used for estimating gross primary productivity (GPP) and yield of grazing lands throughout the world. However, the usefulness of satellite-based images for monitoring rotationally-grazed pastures in the northeastern United States might be limited because paddock size is often smaller than...
Common challenges for ecological modelling: synthesis of facilitated discussions held at the symposia organized for the 2009 conference of the International Society for Ecological Modelling in Quebec City, Canada, (October 6-9, 2009)
Guy R. Larocque, D. Mailly, T.-X. Yue, M. Anand, C. Peng, C. Kazanci, M. Etterson, P. Goethals, S.E. Jorgensen, J.R. Schramski, E.J.B. McIntire, D.J. Marceau, B. Chen, G.Q. Chen, Z.F. Yang, B. Novotna, N. Luckai, Jagtar S. Bhatti, J. Liu, A. Munson, Andrew M. Gordon, J.C. Ascough
2011, Ecological Modelling (222) 2456-2468
The eleven symposia organized for the 2009 conference of the International Society for Ecological Modelling (ISEM 2009) held in Quebec City, Canada, October 6–9, 2009, included facilitated discussion sessions following formal presentations. Each symposium focused on a specific subject, and all the subjects could be classified into three broad categories:...
Environmental controls of wood entrapment in upper Midwestern streams
Eric C. Merten, Jacques Finlay, Lucinda Johnson, Raymond Newman, Heinz Stefan, Bruce C. Vondracek
2011, Hydrological Processes (25) 593-602
Wood deposited in streams provides a wide variety of ecosystem functions, including enhancing habitat for key species in stream food webs, increasing geomorphic and hydraulic heterogeneity and retaining organic matter. Given the strong role that wood plays in streams, factors that influence wood inputs, retention and transport are critical to...
Development of an aquatic pathogen database (AquaPathogen X) and its utilization in tracking emerging fish virus pathogens in North America
E.J. Emmenegger, E. Kentop, T.M. Thompson, S. Pittam, A. Ryan, D. Keon, J.A. Carlino, J. Ranson, R.B. Life, R.M. Troyer, K.A. Garver, Gael Kurath
2011, Journal of Fish Diseases (34) 579-587
The AquaPathogen X database is a template for recording information on individual isolates of aquatic pathogens and is freely available for download (http://wfrc.usgs.gov). This database can accommodate the nucleotide sequence data generated in molecular epidemiological studies along with the myriad of abiotic and biotic traits associated with isolates of various...
Tiny intraplate earthquakes triggered by nearby episodic tremor and slip in Cascadia
J.E. Vidale, A.J. Hotovec, A. Ghosh, K. C. Creager, J. Gomberg
2011, Geochemistry, Geophysics, Geosystems (12)
Episodic tremor and slip (ETS) has been observed in many subduction zones, but its mechanical underpinnings as well as its potential for triggering damaging earthquakes have proven difficult to assess. Here we use a seismic array in Cascadia of unprecedented density to monitor seismicity around a moderate 16 day ETS...
Accelerated construction of a regional DNA-barcode reference library: Caddisflies (Trichoptera) in the Great Smoky Mountains National Park
X. Zhou, J.L. Robinson, C.J. Geraci, C.R. Parker, O.S. Flint Jr., D.A. Etnier, D. Ruiter, R.E. DeWalt, L.M. Jacobus, P.D.N. Hebert
2011, Journal of the North American Benthological Society (30) 131-162
Deoxyribonucleic acid (DNA) barcoding is an effective tool for species identification and lifestage association in a wide range of animal taxa. We developed a strategy for rapid construction of a regional DNA-barcode reference library and used the caddisflies (Trichoptera) of the Great Smoky Mountains National Park (GSMNP) as a model....
Geology and petroleum potential of the north and east margins of the Siberian Craton, north of the Arctic Circle
T. R. Klett, C. J. Wandrey, Janet K. Pitman
2011, Geological Society Memoir 413-431
The Siberian Craton consists of crystalline rocks and superimposed Precambrian sedimentary rocks deposited in rift basins. Palaeozoic rocks, mainly carbonates, were deposited along the margins of the craton to form an outwardly younger concentric pattern that underlies an outward-thickening Mesozoic sedimentary section. The north and east margins of the Siberian...
Long-term biases in geomagnetic K and aa indices
Jeffrey J. Love
2011, Annales Geophysicae (29) 1365-1375
Analysis is made of the geomagnetic-activity aa index and its source K-index data from groups of ground-based observatories in Britain, and Australia, 1868.0–2009.0, solar cycles 11–23. The K data show persistent biases, especially for high (low) K-activity levels at British (Australian) observatories. From examination of multiple subsets of the K data we infer that the biases are not...
Rain pulse response of soil CO2 exchange by biological soil crusts and grasslands of the semiarid Colorado Plateau, United States
David R. Bowling, Edmund E. Grote, Jayne Belnap
2011, Journal of Geophysical Research G: Biogeosciences (116)
Biological activity in arid grasslands is strongly dependent on moisture. We examined gas exchange of biological soil crusts (biocrusts), the underlying soil biotic community, and the belowground respiratory activity of C3 and C4 grasses over 2 years in southeast Utah, USA. We used soil surface CO2 flux and the amount...
Molecular detection of vertebrates in stream water: A demonstration using rocky mountain tailed frogs and Idaho giant salamanders
C.S. Goldberg, D. S. Pilliod, R.S. Arkle, L.P. Waits
2011, PLoS ONE (6)
Stream ecosystems harbor many secretive and imperiled species, and studies of vertebrates in these systems face the challenges of relatively low detection rates and high costs. Environmental DNA (eDNA) has recently been confirmed as a sensitive and efficient tool for documenting aquatic vertebrates in wetlands and in a large river...