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Page 769, results 19201 - 19225

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Not all publications have extents, not all extents are completely accurate
Do well-connected landscapes promote road-related mortality?
C. Grilo, F. Ascensao, M. Santos-Reis, J.A. Bissonette
2011, European Journal of Wildlife Research (57) 707-716
Cost surface (CS) models have emerged as a useful tool to examine the interactions between landscapes patterns and wildlife at large-scale extents. This approach is particularly relevant to guide conservation planning for species that show vulnerability to road networks in human-dominated landscapes. In this study, we measured the functional connectivity...
Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of assimilation at spreading centers
V.D. Wanless, M.R. Perfit, W.I. Ridley, P.J. Wallace, Craig B. Grimes, E.M. Klein
2011, Chemical Geology (287) 54-65
Most geochemical variability in MOR basalts is consistent with low- to moderate-pressure fractional crystallization of various mantle-derived parental melts. However, our geochemical data from MOR high-silica glasses, including new volatile and oxygen isotope data, suggest that assimilation of altered crustal material plays a significant role in the petrogenesis of dacites...
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....
Compensatory effects of recruitment and survival when amphibian populations are perturbed by disease
E. Muths, R. D. Scherer, D. S. Pilliod
2011, Journal of Applied Ecology (48) 873-879
The need to increase our understanding of factors that regulate animal population dynamics has been catalysed by recent, observed declines in wildlife populations worldwide. Reliable estimates of demographic parameters are critical for addressing basic and applied ecological questions and understanding the response of parameters to perturbations (e.g. disease, habitat loss,...
Seismic hazard and risk assessments for Beijing-Tianjin-Tangshan, China, area
F. Xie, Z. Wang, J. Liu
2011, Pure and Applied Geophysics (168) 731-738
Seismic hazard and risk in the Beijing–Tianjin–Tangshan, China, area were estimated from 500-year intensity observations. First, we digitized the intensity observations (maps) using ArcGIS with a cell size of 0.1 × 0.1°. Second, we performed a statistical analysis on the digitized intensity data, determined an average b value (0.39), and derived the intensity–frequency relationship...
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...
Calibration of models using groundwater age
Ward E. Sanford
2011, Hydrogeology Journal (19) 13-16
There have been substantial efforts recently by geochemists to determine the age of groundwater (time since water entered the system) and its uncertainty, and by hydrologists to use these data to help calibrate groundwater models. This essay discusses the calibration of models using groundwater age, with conclusions that emphasize what...
Algal bioassessment metrics for wadeable streams and rivers of Maine, USA
Thomas J. Danielson, Cynthia S. Loftin, Leonidas Tsomides, Jeanne L. DiFranco, Beth Connors
2011, Freshwater Science (30) 1033-1048
Many state water-quality agencies use biological assessment methods based on lotic fish and macroinvertebrate communities, but relatively few states have incorporated algal multimetric indices into monitoring programs. Algae are good indicators for monitoring water quality because they are sensitive to many environmental stressors. We evaluated benthic algal community attributes along...
Coulomb stress change sensitivity due to variability in mainshock source models and receiving fault parameters: A case study of the 2010-2011 Christchurch, New Zealand, earthquakes
Zhongwen Zhan, Bikai Jin, Shengji Wei, Robert W. Graves
2011, Seismological Research Letters (82) 800-814
Strong aftershocks following major earthquakes present significant challenges for infrastructure recovery as well as for emergency rescue efforts. A tragic instance of this is the 22 February 2011 Mw 6.3 Christchurch aftershock in New Zealand, which caused more than 100 deaths while the 2010 Mw 7.1 Canterbury mainshock did not...
Chapter 5: Greater sage-grouse: General use and roost site occurrence with pellet counts as a measure of relative abundance
Steve E. Hanser, Cameron L. Aldridge, Matthias Leu, Mary M. Rowland, Scott E. Nielsen, Steven T. Knick
2011, Book chapter, Sagebrush ecosystem conservation and management: Ecoregional assessment tools and models for the Wyoming Basins
Greater sage-grouse (Centrocercus urophasianus) have been declining both spatially and numerically throughout their range because of anthropogenic disturbance and loss and fragmentation of sagebrush (Artemisia spp.) habitats. Understanding how sage-grouse respond to these habitat alterations and disturbances, particularly the types of disturbances and extent at which they respond, is critical...
Is the northern high-latitude land-based CO2 sink weakening?
D.J. Hayes, A. D. McGuire, D. W. Kicklighter, K.R. Gurney, T.J. Burnside, J. M. Melillo
2011, Global Biogeochemical Cycles (25)
Studies indicate that, historically, terrestrial ecosystems of the northern high-latitude region may have been responsible for up to 60% of the global net land-based sink for atmospheric CO2. However, these regions have recently experienced remarkable modification of the major driving forces of the carbon cycle, including surface air temperature warming...
Chapter 7: Occurrence and abundance of ants, reptiles, and mammals
Steve E. Hanser, Matthias Leu, Cameron L. Aldridge, Scott E. Nielsen, Mary M. Rowland, Steven T. Knick
2011, Book chapter, Sagebrush ecosystem conservation and management: Ecoregional assessment tools and models for the Wyoming Basins
Sagebrush (Artemisia spp.)- associated wildlife are threatened by habitat loss and fragmentation and by impacts associated with anthropogenic disturbances, including energy development. Understanding how species of concern as well as other wildlife including insects, reptiles, and mammals respond to type and spatial scale of disturbance is critical to managing future...
Chapter 8: Occurrence of large and medium-sized mammals: Occurrence but not count models predict pronghorn distribution
Matthias Leu, Steve E. Hanser, Cameron L. Aldridge, Scott E. Nielsen, Lowell H. Suring, Steven T. Knick
2011, Book chapter, Sagebrush ecosystem conservation and management: Ecoregional assessment tools and models for the Wyoming Basins
Management of medium to large-sized terrestrial mammals (Antilocapridae, Canidae, Cervidae, Leporidae, Mustelidae, Ochotonidae) in the western United States is multifaceted and complex. Species in this group generally are charismatic and provide economic opportunities, although others are considered a nuisance at one extreme or are listed as species of conservation concern...
Ground motion attenuation during M 7.1 Darfield and M 6.2 Christchurch, New Zealand, earthquakes and performance of global predictive models
Margaret Segou, Erol Kalkan
2011, Seismological Research Letters (82) 866-874
The M 7.1 Darfield earthquake occurred 40 km west of Christchurch (New Zealand) on 4 September 2010. Six months after, the city was struck again with an M 6.2 event on 22 February local time (21 February UTC). These events resulted in significant damage to infrastructure in the city...
Biological and geochemical controls on diel dissolved inorganic carbon cycling in a low-order agricultural stream: Implications for reach scales and beyond
Craig Tobias, J.K. Bohlke
2011, Chemical Geology (283) 18-30
Movement of dissolved inorganic carbon (DIC) through the hydrologic cycle is an important component of global carbon budgets, but there is considerable uncertainty about the controls of DIC transmission from landscapes to streams, and through river networks to the oceans. In this study, diel measurements of DIC, d13C-DIC, dissolved oxygen...
Thermal removal from near-infrared imaging spectroscopy data of the Moon
Roger N. Clark, Carle M. Pieters, Robert O. Green, J.W. Boardman, Noah E. Petro
2011, Journal of Geophysical Research E: Planets (116) 1-9
In the near-infrared from about 2 μm to beyond 3 μm, the light from the Moon is a combination of reflected sunlight and emitted thermal emission. There are multiple complexities in separating the two signals, including knowledge of the local solar incidence angle due to topography, phase angle dependencies, emissivity, and instrument...
Elevated gas hydrate saturation within silt and silty clay sediments in the Shenhu area, South China Sea
Xiujuan Wang, Deborah R. Hutchinson, Shiguo Wu, Shengxiong Yang, Yiqun Guo
2011, Journal of Geophysical Research B: Solid Earth (116)
Gas hydrate saturations were estimated using five different methods in silt and silty clay foraminiferous sediments from drill hole SH2 in the South China Sea. Gas hydrate saturations derived from observed pore water chloride values in core samples range from 10 to 45% of the pore space at 190–221 m...
Methodology for prediction of rip currents using a three-dimensional numerical, coupled, wave current model
George Voulgaris, Nirnimesh Kumar, John C. Warner
Stephen Leatherman, John Fletemeyer, editor(s)
2011, Conference Paper, Rip currents: Beach safety, physical oceanography, and wave modeling
Rip current currents constitute one of the most common hazards in the nearshore that threaten the lives of the unaware public that makes recreational use of the coastal zone. Society responds to this danger through a number of measures that include: (a) the deployment of trained lifeguards; (b) public education...
Inversion of multi-frequency electromagnetic induction data for 3D characterization of hydraulic conductivity
Troy R. Brosten, Frederick D. Day-Lewis, Gregory M. Schultz, Gary P. Curtis, John W. Lane Jr.
2011, Journal of Applied Geophysics (73) 323-335
Electromagnetic induction (EMI) instruments provide rapid, noninvasive, and spatially dense data for characterization of soil and groundwater properties. Data from multi-frequency EMI tools can be inverted to provide quantitative electrical conductivity estimates as a function of depth. In this study, multi-frequency EMI data collected across an abandoned uranium mill site...
An ecosystem-scale model for the spread of a host-specific forest pathogen in the Greater Yellowstone Ecosystem
J.A. Hatala, M.C. Dietze, R.L. Crabtree, Katherine C. Kendall, D. Six, P.R. Moorcroft
2011, Ecological Applications (21) 1138-1153
The introduction of nonnative pathogens is altering the scale, magnitude, and persistence of forest disturbance regimes in the western United States. In the high-altitude whitebark pine (Pinus albicaulis) forests of the Greater Yellowstone Ecosystem (GYE), white pine blister rust (Cronartium ribicola) is an introduced fungal pathogen that is...
Introduction
W. Nelson Beyer, James P. Meador
W. Nelson Beyer, James P. Meador, editor(s)
2011, Book chapter, Environmental contaminants in biota: Interpreting tissue concentrations, Second Edition
Ecotoxicology is the study of the movement of environmental contaminants through ecosystems and their effects on plants and animals. Examining tissue residues of these contaminants in biota is basic to ecotoxicology, both for understanding the movement of contaminants within organisms and through food chains, and for understanding and quantifying injuries...
Estimation of mussel population response to hydrologic alteration in a southeastern U.S. stream
James T. Peterson, J.M. Wisniewski, C.P. Shea, Jackson C. Rhett
2011, Environmental Management (48) 109-122
The southeastern United States has experienced severe, recurrent drought, rapid human population growth, and increasing agricultural irrigation during recent decades, resulting in greater demand for the water resources. During the same time period, freshwater mussels (Unioniformes) in the region have experienced substantial population declines. Consequently, there is growing interest in...
Recovery of native treefrogs after removal of nonindigenous Cuban Treefrogs, Osteopilus septentrionalis
K.G. Rice, J.H. Waddle, M.W. Miller, M.E. Crockett, F.J. Mazzotti, H.F. Percival
2011, Herpetologica (67) 105-117
Florida is home to several introduced animal species, especially in the southern portion of the state. Most introduced species are restricted to the urban and suburban areas along the coasts, but some species, like the Cuban Treefrog (Osteopilus septentrionalis), are locally abundant in natural protected areas. Although Cuban...
Atacamite and paratacamite from the ultramafic-hosted Logatchev seafloor vent field (14°45′N, Mid-Atlantic Ridge)
Vesselin Dekov, Tanya Boycheva, Ulf Halenius, Sven Petersen, Kjell Billstrom, Jens Stummeyer, G. Kamenov, W. Shanks
2011, Chemical Geology (286) 169-184
Atacamite and paratacamite are ubiquitous minerals associated with Cu-rich massive sulfides at the Logatchev hydrothermal field (Mid-Atlantic Ridge). In this work we provide new details on the mineralogy and geochemistry of these basic cupric chlorides. Our data support the notion that atacamite and paratacamite formation at submarine vent fields is...
Effects of fringing reefs on tsunami inundation: American Samoa
G. Gelfenbaum, A. Apotsos, A.W. Stevens, B. Jaffe
2011, Earth-Science Reviews (107) 12-22
A numerical model of tsunami inundation, Delft3D, which has been validated for the 29 September 2009 tsunami in Tutuila, American Samoa, is used to better understand the impact of fringing coral reefs and embayments on tsunami wave heights, inundation distances, and velocities. The inundation model is used to explore the...