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Page 788, results 19676 - 19700

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Beneath the veil: Plant growth form influences the strength of species richness-productivity relationships in forests
B. Oberle, J.B. Grace, J.M. Chase
2009, Global Ecology and Biogeography (18) 416-425
Aim: Species richness has been observed to increase with productivity at large spatial scales, though the strength of this relationship varies among functional groups. In forests, canopy trees shade understorey plants, and for this reason we hypothesize that species richness of canopy trees will depend on macroclimate, while species richness...
The contemporary cement cycle of the United States
A. Kapur, H. G. Van Oss, G. Keoleian, S.E. Kesler, A. Kendall
2009, Journal of Material Cycles and Waste Management (11) 155-165
A country-level stock and flow model for cement, an important construction material, was developed based on a material flow analysis framework. Using this model, the contemporary cement cycle of the United States was constructed by analyzing production, import, and export data for different stages of the cement cycle. The United...
Broadening our approaches to studying dispersal in raptors
J. L. Morrison, P.B. Wood
2009, Journal of Raptor Research (43) 81-89
Dispersal is a behavioral process having consequences for individual fitness and population dynamics. Recent advances in technology have spawned new theoretical examinations and empirical studies of the dispersal process in birds, providing opportunities for examining how this information may be applied to studies of the dispersal process in raptors. Many...
Titan's surface at 2.2-cm wavelength imaged by the Cassini RADAR radiometer: Calibration and first results
M.A. Janssen, R. D. Lorenz, R. West, F. Paganelli, R.M. Lopes, R. L. Kirk, C. Elachi, S. D. Wall, W.T.K. Johnson, Y. Anderson, R.A. Boehmer, P. Callahan, Y. Gim, G.A. Hamilton, K.D. Kelleher, L. Roth, B. Stiles, Gall A. Le
2009, Icarus (200) 222-239
The first comprehensive calibration and mapping of the thermal microwave emission from Titan's surface is reported based on radiometric data obtained at 2.2-cm wavelength by the passive radiometer included in the Cassini Radar instrument. The data reported were accumulated from 69 separate observational segments in Titan passes from Ta (October...
Halogen degassing during ascent and eruption of water-poor basaltic magma
M. Edmonds, T.M. Gerlach, Richard A. Herd
2009, Chemical Geology (263) 122-130
A study of volcanic gas composition and matrix glass volatile concentrations has allowed a model for halogen degassing to be formulated for K??lauea Volcano, Hawai'i. Volcanic gases emitted during 2004-2005 were characterised by a molar SO2/HCl of 10-64, with a mean of 33; and a molar HF/HCl of 0-5, with...
Case study of a full-scale evapotranspiration cover
Patrick E. McGuire, Brian J. Andraski, Ryan E. Archibald
2009, Journal of Geotechnical and Geoenvironmental Engineering (135) 316-332
The design, construction, and performance analyses of a 6.1ha evapotranspiration (ET) landfill cover at the semiarid U.S. Army Fort Carson site, near Colorado Springs, Colo. are presented. Initial water-balance model simulations, using literature reported soil hydraulic data, aided selection of borrow-source soil type(s) that resulted in predictions...
Post-fledging movements of juvenile Common Mergansers (mergus merganser) in Alaska as inferred by satellite telemetry
John M. Pearce, Margaret R. Petersen
2009, Waterbirds (32) 133-137
We implanted satellite transmitters into eight juvenile Common Mergansers to investigate post-fledging movements from their natal river in southcentral Alaska. Subsequently, they moved widely throughout portions of western and southcentral Alaska up to 750 km from their natal areas during fall and winter months. Transmitters of two birds (one male...
Internal tidal currents in the Gaoping (Kaoping) Submarine Canyon
I.-H. Lee, Y. #NAME? Wang, J.T. Liu, W.-S. Chuang, J. Xu
2009, Journal of Marine Systems (76) 397-404
Data from five separate field experiments during 2000-2006 were used to study the internal tidal flow patterns in the Gaoping (formerly spelled Kaoping) Submarine Canyon. The internal tides are large with maximum interface displacements of about 200??m and maximum velocities of over 100cm/s. They are characterized by a first-mode velocity...
Assessing spatial uncertainty in reservoir characterization for carbon sequestration planning using public well-log data: A case study
E.R. Venteris, K.M. Carter
2009, Environmental Geosciences (16) 211-234
Mapping and characterization of potential geologic reservoirs are key components in planning carbon dioxide (CO2) injection projects. The geometry of target and confining layers is vital to ensure that the injected CO2 remains in a supercritical state and is confined to the target layer. Also, maps of injection volume (porosity)...
Isomer-specific determination of 4-nonylphenols using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry
R.P. Eganhouse, J. Pontolillo, R.B. Gaines, G.S. Frysinger, F.L.P. Gabriel, H.-P.E. Kohler, W. Giger, L. B. Barber
2009, Environmental Science & Technology (43) 9306-9313
Technical nonylphenol (tNP), used for industrial production of nonylphenol polyethoxylate surfactants, is a complex mixture of C3−10-phenols. The major components, 4-nonylphenols, are weak endocrine disruptors whose estrogenicities vary according to the structure of the branched nonyl group. Thus, accurate risk assessment requires isomer-specific determination of 4-NPs. Comprehensive...
Mesohaline submerged aquatic vegetation survey along the U.S. gulf of Mexico coast, 2001 and 2002: A salinity gradient approach
J.H. Merino, J. Carter, S.L. Merino
2009, Gulf of Mexico Science (27) 9-20
Distribution of marine submerged aquatic vegetation (SAV; i.e., seagrass) in the northern Gulf of Mexico coast has been documented, but there are nonmarine submersed or SAV species occurring in estuarine salinities that have not been extensively reported. We sampled 276 SAV beds along the gulf coast in Florida, Alabama, Mississippi,...
Spatial habitat use patterns of sea otters in coastal washington
K.L. Laidre, R.J. Jameson, E. Gurarie, S.J. Jeffries, H. Allen
2009, Journal of Mammalogy (90) 906-917
Sea otter (Enhydra lutris kenyoni) movements, home range, and activity budgets were described from data collected during very-high-frequency radiotelemetry studies of 75 individuals on the outer coast of Washington State between 1992 and 1999. Sea otters were located at least once per week from 22 accessible sites along the coast....
A multiscale analysis of coral reef topographic complexity using lidar-derived bathymetry
D.G. Zawada, J. C. Brock
2009, Journal of Coastal Research 6-15
Coral reefs represent one of the most irregular substrates in the marine environment. This roughness or topographic complexity is an important structural characteristic of reef habitats that affects a number of ecological and environmental attributes, including species diversity and water circulation. Little is known about the range of topographic complexity...
Water balance dynamics in the Nile Basin
Gabriel B. Senay, Kwabena Asante, Guleid A. Artan
2009, Hydrological Processes (23) 3675-3681
Understanding the temporal and spatial dynamics of key water balance components of the Nile River will provide important information for the management of its water resources. This study used satellite-derived rainfall and other key weather variables derived from the Global Data Assimilation System to estimate and map the distribution of...
Unraveling the stratigraphy of the Oriskany Sandstone: A necessity in assessing its site-specific carbon sequestration potential
J. Kostelnik, K.M. Carter
2009, Environmental Geosciences (16) 187-200
The widespread distribution, favorable reservoir characteristics, and depth make the Lower Devonian Oriskany Sandstone a viable sequestration target in the Appalachian Basin. The Oriskany Sandstone is thickest in the structurally complex Ridge and Valley Province, thins toward the northern and western basin margins, and is even absent in other parts...
Small-footprint, waveform-resolving lidar estimation of submerged and sub-canopy topography in coastal environments
A. Nayegandhi, J. C. Brock, C. W. Wright
2009, International Journal of Remote Sensing (30) 861-878
The experimental advanced airborne research lidar (EAARL) is an airborne lidar instrument designed to map near-shore submerged topography and adjacent land elevations simultaneously. This study evaluated data acquired by the EAARL system in February 2003 and March 2004 along the margins of Tampa Bay, Florida, USA, to map bare-earth elevations...
Extraction of lidar-based dune-crest elevations for use in examining the vulnerability of beaches to inundation during hurricanes
H.F. Stockdon, K.S. Doran, A. H. Sallenger Jr.
2009, Journal of Coastal Research 59-65
The morphology of coastal sand dunes plays an important role in determining how a beach will respond to a hurricane. Accurate measurements of dune height and position are essential for assessing the vulnerability of beaches to extreme coastal change during future landfalls. Lidar topographic surveys provide rapid, accurate, high-resolution datasets...
Weathering of the New Albany Shale, Kentucky, USA: I. Weathering zones defined by mineralogy and major-element composition
M.L.W. Tuttle, G. N. Breit
2009, Applied Geochemistry (24) 1549-1564
Comprehensive understanding of chemical and mineralogical changes induced by weathering is valuable information when considering the supply of nutrients and toxic elements from rocks. Here minerals that release and fix major elements during progressive weathering of a bed of Devonian New Albany Shale in eastern Kentucky are documented. Samples were...
Sensitivity analysis, calibration, and testing of a distributed hydrological model using error‐based weighting and one objective function
L. Foglia, Mary C. Hill, Steffen W. Mehl, P. Burlando
2009, Water Resources Research (45)
We evaluate the utility of three interrelated means of using data to calibrate the fully distributed rainfall‐runoff model TOPKAPI as applied to the Maggia Valley drainage area in Switzerland. The use of error‐based weighting of observation and prior information data, local sensitivity analysis, and single‐objective function nonlinear regression provides quantitative...
The effect of bathymetric filtering on nearshore process model results
N.G. Plant, K.L. Edwards, J.M. Kaihatu, J. Veeramony, L. Hsu, K. T. Holland
2009, Coastal Engineering (56) 484-493
Nearshore wave and flow model results are shown to exhibit a strong sensitivity to the resolution of the input bathymetry. In this analysis, bathymetric resolution was varied by applying smoothing filters to high-resolution survey data to produce a number of bathymetric grid surfaces. We demonstrate that the sensitivity of model-predicted...
Objective rapid delineation of areas at risk from block-and-ash pyroclastic flows and surges
C. Widiwijayanti, B. Voight, D. Hidayat, S. P. Schilling
2009, Bulletin of Volcanology (71) 687-703
Assessments of pyroclastic flow (PF) hazards are commonly based on mapping of PF and surge deposits and estimations of inundation limits, and/or computer models of varying degrees of sophistication. In volcanic crises a PF hazard map may be sorely needed, but limited time, exposures, or safety aspects may preclude fieldwork,...
Seismic analysis of clinoform depositional sequences and shelf-margin trajectories in Lower Cretaceous (Albian) strata, Alaska North Slope
David W. Houseknecht, Kenneth J. Bird, Christopher J. Schenk
2009, Basin Research (21) 644-654
Lower Cretaceous strata beneath the Alaska North Slope include clinoform depositional sequences that filled the western Colville foreland basin and overstepped the Beaufort rift shoulder. Analysis of Albian clinoform sequences with two‐dimensional (2D) seismic data resulted in the recognition of seismic facies inferred to represent lowstand, transgressive and highstand systems...
Assessing the landscape context and conversion risk of protected areas using satellite data products
Leona K. Svancara, J. M. Scott, Thomas R. Loveland, Anna Pidgorna
2009, Remote Sensing of Environment (113) 1357-1369
Since the establishment of the first national park (Yellowstone National Park in 1872) and the first wildlife refuge (Pelican Island in 1903), dramatic changes have occurred in both ecological and cultural landscapes across the U.S. The ability of these protected areas to maintain current levels of biodiversity depend, at least...
Hierarchical demographic approaches for assessing invasion dynamics of non-indigenous species: An example using northern snakehead (Channa argus)
Y. Jiao, N.W.R. Lapointe, P. L. Angermeier, B.R. Murphy
2009, Ecological Modelling (220) 1681-1689
Models of species' demographic features are commonly used to understand population dynamics and inform management tactics. Hierarchical demographic models are ideal for the assessment of non-indigenous species because our knowledge of non-indigenous populations is usually limited, data on demographic traits often come from a species' native range, these traits vary...
Determination of diffusion coefficients of hydrogen in fused silica between 296 and 523 K by Raman spectroscopy and application of fused silica capillaries in studying redox reactions
L. Shang, I-Ming Chou, W. Lu, Robert Burruss, Y. Zhang
2009, Geochimica et Cosmochimica Acta (73) 5435-5443
Diffusion coefficients (D) of hydrogen in fused silica capillaries (FSC) were determined between 296 and 523 K by Raman spectroscopy using CO2 as an internal standard. FSC capsules (3.25 × 10−4 m OD, 9.9 × 10−5 m ID, and ∼0.01 m long) containing CO2 and H2were prepared and the initial relative concentrations of hydrogen in these capsules were derived from...