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Page 1766, results 44126 - 44150

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Not all publications have extents, not all extents are completely accurate
Acetate availability and its influence on sustainable bioremediation of Uranium-contaminated groundwater
K.H. Williams, P.E. Long, J.A. Davis, M.J. Wilkins, A. L. N’Guessan, Carl Steefel, L. Yang, D. Newcomer, F.A. Spane, L.J. Kerkhof, L. Mcguinness, R. Dayvault, Derek R. Lovley
2011, Geomicrobiology Journal (28) 519-539
Field biostimulation experiments at the U.S. Department of Energy's Integrated Field Research Challenge (IFRC) site in Rifle, Colorado, have demonstrated that uranium concentrations in groundwater can be decreased to levels below the U.S. Environmental Protection Agency's (EPA) drinking water standard (0.126 μM). During successive summer experiments – referred to as...
Sea ice loss enhances wave action at the Arctic coast
I. Overeem, R. Scott Anderson, C.W. Wobus, Gary D. Clow, Frank E. Urban, N. Matell
2011, Geophysical Research Letters (38)
Erosion rates of permafrost coasts along the Beaufort Sea accelerated over the past 50 years synchronously with Arctic‐wide declines in sea ice extent, suggesting a causal relationship between the two. A fetch‐limited wave model driven by sea ice position and local wind data from northern Alaska indicates that the exposure...
Maintenance of phenotypic variation: Repeatability, heritability and size-dependent processes in a wild brook trout population
B. H. Letcher, J.A. Coombs, K.H. Nislow
2011, Evolutionary Applications (4) 602-615
Phenotypic variation in body size can result from within-cohort variation in birth dates, among-individual growth variation and size-selective processes. We explore the relative effects of these processes on the maintenance of wide observed body size variation in stream-dwelling brook trout (Salvelinus fontinalis). Based on the analyses of multiple recaptures of...
Horizontal movements of Atlantic blue marlin (Makaira nigricans) in the Gulf of Mexico
Richard T. Kraus, R.J.D. Wells, J.R. Rooker
2011, Marine Biology (158) 699-713
We examined movements of Atlantic blue marlin (Makaira nigricans) from the Gulf of Mexico based upon 42 pop-up archival transmitting (PAT) tags. Long deployments (including one 334-day track) revealed diverse movement patterns within the Gulf of Mexico. North–south seasonal changes in blue marlin distribution showed strong correspondence with established seasonal...
Demonstration of a conceptual model for using LiDAR to improve the estimation of floodwater mitigation potential of Prairie Pothole Region wetlands
S. Huang, Caitlin Young, M. Feng, Hans Karl Heidemann, Matthew Cushing, D.M. Mushet, S. Liu
2011, Journal of Hydrology (405) 417-426
Recent flood events in the Prairie Pothole Region of North America have stimulated interest in modeling water storage capacities of wetlands and their surrounding catchments to facilitate flood mitigation efforts. Accurate estimates of basin storage capacities have been hampered by a lack of high-resolution elevation data. In this paper, we...
An occurrence of the protocetid whale "Eocetus" wardii in the middle Eocene Piney Point Formation of Virginia
Robert E. Weems, Lucy E. Edwards, Jason E. Osborne, A.A. Alford
2011, Journal of Paleontology (85) 271-278
Two protocetid whale vertebrae, here referred to “Eocetus” wardii, have been recovered from the riverbed of the Pamunkey River in east-central Virginia. Neither bone was found in situ, but both were found with lumps of lithified matrix cemented to their surfaces. Most of this matrix was removed and processed for...
Nitrous oxide emission from denitrification in stream and river networks
J. J. Beaulieu, J. L. Tank, S. K. Hamilton, W. M. Wollheim, R. O. Hall Jr., P. J. Mulholland, B. J. Peterson, L. R. Ashkenas, L. W. Cooper, Clifford N. Dahm, W. K. Dodds, N. B. Grimm, S. L. Johnson, W. H. McDowell, G. C. Poole, Valett H. Maurice, C. P. Arango, M. J. Bernot, A. J. Burgin, C. L. Crenshaw, A. M. Helton, L. T. Johnson, J. M. O’Brien, J. D. Potter, R.W. Sheibley, D. J. Sobota, S. M. Thomas
2011, Proceedings of the National Academy of Sciences of the United States of America (108) 214-219
Nitrous oxide (N2O) is a potent greenhouse gas that contributes to climate change and stratospheric ozone destruction. Anthropogenic nitrogen (N) loading to river networks is a potentially important source of N2O via microbial denitrification that converts N to N2O and dinitrogen (N2). The...
Effects of black bear relocation on elk calf recruitment at Great Smoky Mountains National Park
J. Yarkovich, J. D. Clark, J.L. Murrow
2011, Journal of Wildlife Management (75) 1145-1154
Previous research from 2001 to 2006 on an experimentally released elk (Cervus elaphus) population at Great Smoky Mountains National Park (GSMNP or Park) indicated that calf recruitment (i.e., calves reaching 1 yr of age per adult female elk) was low (0.306, total SE = 0.090) resulting in low or negative population growth...
Causes of systematic over- or underestimation of low streamflows by use of index-streamgage approaches in the United States
K. Eng, J.E. Kiang, Y.-Y. Chen, D.M. Carlisle, G.E. Granato
2011, Hydrological Processes (25) 2211-2220
Low-flow characteristics can be estimated by multiple linear regressions or the index-streamgage approach. The latter transfers streamflow information from a hydrologically similar, continuously gaged basin ('index streamgage') to one with a very limited streamflow record, but often results in biased estimates. The application of the index-streamgage approach can be generalized...
Mapping permeability over the surface of the Earth
T. Gleeson, L. Smith, N. Moosdorf, J. Hartmann, H.H. Durr, Andrew H. Manning, L. P. H. Van Beek, A. Mark Jellinek
2011, Geophysical Research Letters (38)
Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional‐scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed,...
Three-dimensional model of an ultramafic feeder system to the Nikolai Greenstone mafic large igneous province, central Alaska Range
Jonathan M.G. Glen, Jeanine M. Schmidt, G. G. Connard
2011, Geochemistry, Geophysics, Geosystems (12)
The Amphitheater Mountains and southern central Alaska Range expose a thick sequence of Triassic Nikolai basalts that is underlain by several mafic‐ultramafic complexes, the largest and best exposed being the Fish Lake and Tangle (FL‐T) mafic‐ultramafic sills that flank the Amphitheater Mountains synform. Three‐dimensional (3‐D) modeling of gravity and magnetic...
Dynamic resource allocation in conservation planning
D. Golovin, A. Krause, B. Gardner, Sarah J. Converse, S. Morey
2011, Conference Paper, Proceedings of the National Conference on Artificial Intelligence
Consider the problem of protecting endangered species by selecting patches of land to be used for conservation purposes. Typically, the availability of patches changes over time, and recommendations must be made dynamically. This is a challenging prototypical example of a sequential optimization problem under uncertainty in computational sustainability. Existing techniques...
Circum-Arctic mapping project: New magnetic and gravity anomaly maps of the Arctic
C. Gaina, S.C. Werner, R. Saltus, S. Maus, S. Aaro, D. Damaske, R. Forsberg, V. Glebovsky, Kevin K. Johnson, J. Jonberger, T. Koren, J. Korhonen, T. Litvinova, G. Oakey, O. Olesen, O. Petrov, M. Pilkington, T. Rasmussen, B. Schreckenberger, M. Smelror
2011, Geological Society Memoir 39-48
New Circum-Arctic maps of magnetic and gravity anomalies have been produced by merging regional gridded data. Satellite magnetic and gravity data were used for quality control of the long wavelengths of the new compilations. The new Circum-Arctic digital compilations of magnetic, gravity and some of their derivatives have been analyzed...
New aerial survey and hierarchical model to estimate manatee abundance
Catherine A. Langtimm, Robert Dorazio, B.M. Stith, T.J. Doyle
2011, Journal of Wildlife Management (75) 399-412
Monitoring the response of endangered and protected species to hydrological restoration is a major component of the adaptive management framework of the Comprehensive Everglades Restoration Plan. The endangered Florida manatee (Trichechus manatus latirostris) lives at the marine-freshwater interface in southwest Florida and is likely to be affected by hydrologic restoration....
Formulation of a correlated variables methodology for assessment of continuous gas resources with an application to the Woodford play, Arkoma Basin, eastern Oklahoma
Ricardo A. Olea, D.W. Houseknecht, C.P. Garrity, T. A. Cook
2011, Boletin Geologico y Minero (122) 483-496
Shale gas is a form of continuous unconventional hydrocarbon accumulation whose resource estimation is unfeasible through the inference of pore volume. Under these circumstances, the usual approach is to base the assessment on well productivity through estimated ultimate recovery (EUR). Unconventional resource assessments that consider uncertainty are typically done by...
Genetic differentiation of the Kittlitz's Murrelet Brachyramphus brevirostris in the Aleutian Islands and Gulf of Alaska
T.P. Birt, D. Mackinnon, John F. Piatt, Vicki L. Friesen
2011, Marine Ornithology: Journal of Seabird Research and Conservation (39) 45-51
Information about the distribution of genetic variation within and among local populations of the Kittlitz's Murrelet Brachyramphus brevirostris is needed for effective conservation of this rare and declining species. We compared variation in a 429 base pair fragment of the mitochondrial control region and 11 microsatellite loci among 53 Kittlitz's...
Revisiting the Earth's sea-level and energy budgets from 1961 to 2008
John A. Church, Neil J. White, Leonard F. Konikow, Catia M. Domingues, J. Graham Cogley, Eric Rignot, Jonathan M. Gregory, Michiel R. van den Broeke, Andrew J. Monaghan, Isabella Velicogna
2011, Geophysical Research Letters (38)
We review the sea-level and energy budgets together from 1961, using recent and updated estimates of all terms. From 1972 to 2008, the observed sea-level rise (1.8 0.2 mm yr-1 from tide gauges alone and 2.1 0.2 mm yr -1 from a combination of tide gauges and altimeter observations) agrees...
Estimating trends in alligator populations from nightlight survey data
Ikuko Fujisaki, F.J. Mazzotti, R.M. Dorazio, Kenneth G. Rice, M. Cherkiss, B. Jeffery
2011, Wetlands (31) 147-155
Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends...
Suspended material availability and filtration-biodeposition processes performed by a native and invasive bivalve species in streams
C.L. Atkinson, M.R. First, A.P. Covich, Stephen P. Opsahl, S.W. Golladay
2011, Hydrobiologia (667) 191-204
Unionid mussels are among the most threatened group of freshwater organisms globally. They are known for their ability to filter food particles from flowing and standing waters. However, invasive bivalve species, such as the Asian clam (Corbicula fluminea) in North America, have the potential to overlap in feeding and potentially...
Vegetation death and rapid loss of surface elevation in two contrasting Mississippi delta salt marshes: The role of sedimentation, autocompaction and sea-level rise
J.W. Day, G.P. Kemp, D.J. Reed, Donald R. Cahoon, R.M. Boumans, J.M. Suhayda, R. Gambrell
2011, Ecological Engineering (37) 229-240
From 1990 to 2004, we carried out a study on accretionary dynamics and wetland loss in salt marshes surrounding two small ponds in the Mississippi delta; Old Oyster Bayou (OB), a sediment-rich area near the mouth of the Atchafalaya River and Bayou Chitigue (BC), a sediment-poor area about 70 km to the east. The OB site was...
Continuity of Landsat observations: Short term considerations
Michael A. Wulder, Joanne C. White, Jeffery G. Masek, John L. Dwyer, David P. Roy
2011, Remote Sensing of Environment (115) 747-751
As of writing in mid-2010, both Landsat-5 and -7 continue to function, with sufficient fuel to enable data collection until the launch of the Landsat Data Continuity Mission (LDCM) scheduled for December of 2012. Failure of one or both of Landsat-5 or -7 may result in a lack of Landsat...
A lognormal distribution of metal resources
Donald A. Singer
2011, Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences (36) 201-208
For national or global resource estimation of frequencies of metals, a lognormal distribution has commonly been recommended but not adequately tested. Tests of frequencies of Cu, Zn, Pb, Ag, and Au contents of 1 984 well-explored mineral deposits display a poor fit to the lognormal distribution. When the same metals...
Estimating aboveground forest biomass carbon and fire consumption in the U.S. Utah High Plateaus using data from the Forest Inventory and Analysis program, Landsat, and LANDFIRE
Xuexia Chen, Shuguang Liu, Zhiliang Zhu, James E. Vogelmann, Zhen Li, Donald O. Ohlen
2011, Ecological Indicators (11) 140-148
The concentrations of CO2 and other greenhouse gases in the atmosphere have been increasing and greatly affecting global climate and socio-economic systems. Actively growing forests are generally considered to be a major carbon sink, but forest wildfires lead to large releases of biomass carbon into the atmosphere. Aboveground forest biomass...
Enhancement of long period components of recorded and synthetic ground motions using InSAR
J.A. Abell, J. Carlos de la Llera, Charles W. Wicks Jr.
2011, Soil Dynamics and Earthquake Engineering (31) 817-829
Tall buildings and flexible structures require a better characterization of long period ground motion spectra than the one provided by current seismic building codes. Motivated by that, a methodology is proposed and tested to improve recorded and synthetic ground motions which are consistent with the observed co-seismic displacement field...
Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts
T. Liebich, S. D. McCormick, D. Kircheis, Kevin Johnson, R. Regal, T. Hrabik
2011, Journal of Fish Biology (79) 502-519
The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream‐water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose,...