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How Human And Natural Driving Forces Affect Pheasants And Pheasant Hunting In South Dakota, Chris Laingen Jan 2008

How Human And Natural Driving Forces Affect Pheasants And Pheasant Hunting In South Dakota, Chris Laingen

Faculty Research and Creative Activity

No abstract provided.

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The Dynamic Evolutionary History Of The Bananaquit (Coereba Flaveola) In The Caribbean Revealed By A Multigene Analysis, Eva Bellemain, Eldredge Bermingham, Robert Ricklefs Jan 2008

The Dynamic Evolutionary History Of The Bananaquit (Coereba Flaveola) In The Caribbean Revealed By A Multigene Analysis, Eva Bellemain, Eldredge Bermingham, Robert Ricklefs

Biology Department Faculty Works

BackgroundThe bananaquit (Coereba flaveola) is a small nectivorous and frugivorous emberizine bird (order Passeriformes) that is an abundant resident throughout the Caribbean region. We used multi-gene analyses to investigate the evolutionary history of this species throughout its distribution in the West Indies and in South and Middle America. We sequenced six mitochondrial genes (3744 base pairs) and three nuclear genes (2049 base pairs) for forty-four bananaquits and three outgroup species. We infer the ancestral area of the present-day bananaquit populations, report on the species' phylogenetic, biogeographic and evolutionary history, and propose scenarios for its diversification and range expansion.ResultsPhylogenetic concordance between …

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Hypogene Calcitization: Evaporite Diagenesis In The Western Delaware Basin, Kevin W. Stafford, Dana Ulmer-Scholle, Laura Rosales-Lagarde Jan 2008

Hypogene Calcitization: Evaporite Diagenesis In The Western Delaware Basin, Kevin W. Stafford, Dana Ulmer-Scholle, Laura Rosales-Lagarde

Faculty Publications

Evaporite calcitization within the Castile Formation of the Delaware Basin is more widespread and diverse than originally recognized. Coupled field and GIS studies have identified more than 1000 individual occurrences of calcitization within the Castile Formation outcrop area, which includes both calcitized masses (limestone buttes) and laterally extensive calcitized horizons (limestone sheets). Both limestone buttes and sheets commonly contain a central brecciated zone that we attribute to hypogene dissolution. Lithologic fabric of calcitized zones ranges from little alteration of original varved laminae to fabrics showing extensive laminae distortion as well as extensive vuggy and open cavernous porosity. Calcitization is most …

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Hypogene Speleogenesis Within The Central Basin Platform: Karst Porosity In The Yates Field, Pecos County, Texas, U.S.A., Kevin W. Stafford, Fred H. Behnken, Jesse G. White Jan 2008

Hypogene Speleogenesis Within The Central Basin Platform: Karst Porosity In The Yates Field, Pecos County, Texas, U.S.A., Kevin W. Stafford, Fred H. Behnken, Jesse G. White

Faculty Publications

The Yates Unit Oil Field is located on the southeastern tip of the Central Basin Platform in eastern Pecos County, Texas. It produces from Middle Permian strata, primarily the upper San Andres Formation. Locally, the productive upper San Andres Formation is comprised of successively vertically stacked progradational shelf carbonates. Stratigraphically overlying the Yates Field reservoir, the Toborg Field produces from the uppermost Triassic and Cretaceous units. Both fields are bounded on the north and east sides by the Pecos River, which has remained entrenched in its current location since the early Tertiary. As mapped, the top of the San Andres …

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Castile Evaporite Karst Potential Map Of The Gypsum Plain, Eddy County, New Mexico And Culberson County, Texas: A Gis Methodological Comparison, Kevin W. Stafford, Laura Rosales-Lagarde, Penelope J. Boston Jan 2008

Castile Evaporite Karst Potential Map Of The Gypsum Plain, Eddy County, New Mexico And Culberson County, Texas: A Gis Methodological Comparison, Kevin W. Stafford, Laura Rosales-Lagarde, Penelope J. Boston

Faculty Publications

Castile Formation gypsum crops out over ,1,800 km2 in the western Delaware Basin where it forms the majority of the Gypsum Plain. Karst development is well recognized in the Gypsum Plain (i.e., filled and open sinkholes with associated caves); however, the spatial occurrence has been poorly known. In order to evaluate the extent and distribution of karst development within the Castile portion of the Gypsum Plain, combined field and Geographic Information System (GIS) studies were conducted, which enable a first approximation of regional speleogenesis and delineate karst-related natural resources for management. Field studies included physical mapping of 50, 1-km2 sites, …

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Sampling Of Malodorous Compounds In Air Using Stir Bar Sorbtive Extraction, John H. Loughrin, Nanh Lovanh, Arturo I. Quintanar, Rezaul Mahmood Jan 2008

Sampling Of Malodorous Compounds In Air Using Stir Bar Sorbtive Extraction, John H. Loughrin, Nanh Lovanh, Arturo I. Quintanar, Rezaul Mahmood

High Plains Regional Climate Center: Staff Publications

Twisters, (poly)‐dimethylsiloxane‐coated magnetic stir bars, were used to measure compounds typical of swine manure malodor in air. In initial experiments, a time to achieve equilibrium was determined by preloading the stir bars with ten compounds with a range of volatilities and polarities and then monitoring their loss. The rate of loss was dependent on compound volatility, and the time for equilibrium to be attained varied widely, from 22 min for phenol to 210 min for skatole. To test whether the Twisters would respond linearly over a range of concentrations, the stir bars were placed in vented jars with solutions of …

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Evaluation Of Modis Ndvi And Ndwi For Vegetation Drought Monitoring Using Oklahoma Mesonet Soil Moisture Data, Yingxin Gu, Eric Hunt, Brian Wardlow, Jeffrey B. Basara, Jesslyn F. Brown, James P. Verdin Jan 2008

Evaluation Of Modis Ndvi And Ndwi For Vegetation Drought Monitoring Using Oklahoma Mesonet Soil Moisture Data, Yingxin Gu, Eric Hunt, Brian Wardlow, Jeffrey B. Basara, Jesslyn F. Brown, James P. Verdin

National Drought Mitigation Center: Faculty Publications

The evaluation of the relationship between satellitederived vegetation indices (normalized difference vegetation index and normalized difference water index) and soil moisture improves our understanding of how these indices respond to soil moisture fluctuations. Soil moisture deficits are ultimately tied to drought stress on plants. The diverse terrain and climate of Oklahoma, the extensive soil moisture network of the Oklahoma Mesonet, and satellitederived indices from the Moderate Resolution Imaging Spectroradiometer (MODIS) provided an opportunity to study correlations between soil moisture and vegetation indices over the 2002–2006 growing seasons. Results showed that the correlation between both indices and the fractional water index …

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The Vegetation Drought Response Index (Vegdri): A New Integrated Approach For Monitoring Drought Stress In Vegetation, Jesslyn F. Brown, Brian D. Wardlow, Tsegaye Tadesse, Michael Hayes, Bradley C. Reed Jan 2008

The Vegetation Drought Response Index (Vegdri): A New Integrated Approach For Monitoring Drought Stress In Vegetation, Jesslyn F. Brown, Brian D. Wardlow, Tsegaye Tadesse, Michael Hayes, Bradley C. Reed

National Drought Mitigation Center: Faculty Publications

The development of new tools that provide timely, detailed-spatial-resolution drought information is essential for improving drought preparedness and response. This paper presents a new method for monitoring drought-induced vegetation stress called the Vegetation Drought Response Index (VegDRI). VegDRI integrates traditional climate-based drought indicators and satellite-derived vegetation index metrics with other biophysical information to produce a 1 km map of drought conditions that can be produced in near-real time. The initial VegDRI map results for a 2002 case study conducted across seven states in the north-central United States illustrates the utility of VegDRI for improved large-area drought monitoring.

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Lead Concentration Of Soils In Sorby Hills Area Of Proposed M2 Irrigation Area, East Kimberley, Edward (Ted) Arnold Griffin, Noel R. Schoknecht, Ross Brennan, Jane Speijers, Dave Allen, Mike Freeman Jan 2008

Lead Concentration Of Soils In Sorby Hills Area Of Proposed M2 Irrigation Area, East Kimberley, Edward (Ted) Arnold Griffin, Noel R. Schoknecht, Ross Brennan, Jane Speijers, Dave Allen, Mike Freeman

Resource management technical reports

No abstract provided.

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Characterization Of Natural Spring Waters Of The San Bernardino Mountains Using Stable Isotopes Of Oxygen And Hydrogen, Alison Renee Sloat Jan 2008

Characterization Of Natural Spring Waters Of The San Bernardino Mountains Using Stable Isotopes Of Oxygen And Hydrogen, Alison Renee Sloat

Theses Digitization Project

The purpose of this study was to characterize the natural spring waters of the San Bernardino Mountains using two stable isotopes. The isotopic results of this study will aid with tracing sources, movements, and mixing effects on groundwater receiving mountain-front recharge in the region.

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Atlantic And Pacific Sst Influences On Medieval Drought In North America Simulated By The Community Atmospheric Model, Song Feng, Robert J. Oglesby, Clinton M. Rowe, David B. Loope, Qi Steven Hu Jan 2008

Atlantic And Pacific Sst Influences On Medieval Drought In North America Simulated By The Community Atmospheric Model, Song Feng, Robert J. Oglesby, Clinton M. Rowe, David B. Loope, Qi Steven Hu

Department of Earth and Atmospheric Sciences: Faculty Publications

Severe drought is arguably one of the greatest recurring natural disasters that strikes North America. A synthesis of multiproxy data shows that North America was in the grip of a severe centennial-scale drought during medieval times (800–1300 AD). In this study, the Community Atmospheric Model (CAM) is used to investigate the role of sea surface temperature (SST) anomalies from the North Atlantic and the tropical Pacific Ocean on this megadrought. These anomalies are obtained from proxy reconstructions of SST. Four model experiments with prescribed SST anomalies in the tropical Pacific and/or North Atlantic Ocean were made. The CAM results captured …

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High-Spectral Resolution Simulation Of Polarization Of Skylight: Sensitivity To Aerosol Vertical Profile, Jing Zeng, Qingyuan Han, Jun Wang Jan 2008

High-Spectral Resolution Simulation Of Polarization Of Skylight: Sensitivity To Aerosol Vertical Profile, Jing Zeng, Qingyuan Han, Jun Wang

Department of Earth and Atmospheric Sciences: Faculty Publications

A vector radiative transfer model was used in conjunction with the line-by-line radiative transfer model and the database of high-resolution transmission (HITRAN) molecular absorption to simulate the degree of linear polarization of skylight in cloud-free conditions. Differences between simulated and measured polarization data in highspectral resolution are found to be within 1% after aerosol scattering and gas absorptions are carefully considered. Limiting experiments are conducted at wavelengths around 0.760–0.765 μm O2-A absorption band for the same columnar aerosol optical thickness but different aerosol profiles. Results showed that the degree of linear polarization of skylight at surface varies strongly …

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Simulation Of Ground-Water Flow And Effects Of Ground-Water Irrigation On Base Flow In The Elkhorn And Loup River Basins, Nebraska, Steven M. Peterson, Jennifer S. Stanton, Amanda T. Saunders, Jesse R. Bradley Jan 2008

Simulation Of Ground-Water Flow And Effects Of Ground-Water Irrigation On Base Flow In The Elkhorn And Loup River Basins, Nebraska, Steven M. Peterson, Jennifer S. Stanton, Amanda T. Saunders, Jesse R. Bradley

United States Geological Survey: Publications

Irrigated agriculture is vital to the livelihood of com¬munities in the Elkhorn and Loup River Basins in Nebraska, and ground water is used to irrigate most of the cropland. Concerns about the sustainability of ground-water and surface-water resources have prompted State and regional agencies to evaluate the cumulative effects of ground-water irrigation in this area. To facilitate understanding of the effects of ground-water irrigation, a numerical computer model was devel¬oped to simulate ground-water flow and assess the effects of ground-water irrigation (including ground-water withdrawals, hereinafter referred to as pumpage, and enhanced recharge) on stream base flow.
The study area covers …

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Modelling The Deformation Front Of A Fold-Thrust Belt: The Effect Of An Upper Detachment Horizon (Abstract), Caroline M. Burberry, H. Koyi, F. Nilfouroushan, John W. Cosgrove Jan 2008

Modelling The Deformation Front Of A Fold-Thrust Belt: The Effect Of An Upper Detachment Horizon (Abstract), Caroline M. Burberry, H. Koyi, F. Nilfouroushan, John W. Cosgrove

Department of Earth and Atmospheric Sciences: Faculty Publications

First sentence of abstract: Structures found at the deformation fronts of fold-thrust belts are variable in type, geometry and spatial organisation, as can be demonstrated from comparisons between structures in the Zagros Fold-Thrust Belt, Iran and the Sawtooth Range, Montana.

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Preliminary Results From A Holocene Record From Crystal Lake, Southwestern Ohio, Rebecca Teed, Leigh Deuter, Ashley Kesler, Graham Parker, Melissa Sparks Jan 2008

Preliminary Results From A Holocene Record From Crystal Lake, Southwestern Ohio, Rebecca Teed, Leigh Deuter, Ashley Kesler, Graham Parker, Melissa Sparks

Earth and Environmental Sciences Faculty Publications

No abstract provided.

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Kinematic Analysis Of Mylonitic Rocks, Southern Ruby Mountains, Sw Montana: Evidence For Proterozoic Orogenic Crustal Thickening And Topographic Collapse, Jessica Sousa Jan 2008

Kinematic Analysis Of Mylonitic Rocks, Southern Ruby Mountains, Sw Montana: Evidence For Proterozoic Orogenic Crustal Thickening And Topographic Collapse, Jessica Sousa

Undergraduate Review

Mylonitic granitic rocks from a large shear zone within the southern Ruby Mountains in southwest Montana record evidence for a multiple tectonic movement history. The shear zone is 500 meters thick with ductile shear fabrics generally striking northeast and dipping to the northwest. Foliations in the adjacent country rocks are sub-parallel to the foliations within the mylonites suggesting shear zone development was contemporaneous with the regional deformation and metamorphism of the country rock. A well-developed mineral stretching lineation, defined by aligned sillimanite crystals, records predominantly dip-slip movement, but locally, oblique-slip is also preserved. Sheath-type folds developed in thin calc-silicate layers …

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Environmental Factors Affecting Mercury In Camp Far West Reservoir, California, 2001–03, Charles N. Alpers, A. Robin Stewart, Michael K. Saiki, Mark C. Marvin-Dipasquale, Brent R. Topping, Kelly M. Rider, Steven K. Gallanthine, Cynthia A. Kester, Robert O. Rye, Ronald C. Antweiler, John F. De Wild Jan 2008

Environmental Factors Affecting Mercury In Camp Far West Reservoir, California, 2001–03, Charles N. Alpers, A. Robin Stewart, Michael K. Saiki, Mark C. Marvin-Dipasquale, Brent R. Topping, Kelly M. Rider, Steven K. Gallanthine, Cynthia A. Kester, Robert O. Rye, Ronald C. Antweiler, John F. De Wild

United States Geological Survey: Publications

This report documents water quality in Camp Far West Reservoir from October 2001 through August 2003. The reservoir, located at approximately 300 feet above sea level in the foothills of the northwestern Sierra Nevada, California, is a monomictic lake characterized by extreme drawdown in the late summer and fall. Thermal stratification in summer and fall is coupled with anoxic conditions in the hypolimnion. Water-quality sampling was done at approximately 3-month intervals on eight occasions at several stations in the reservoir, including a group of three stations along a flow path in the reservoir: an upstream station in the Bear River …

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Evapotranspiration Rates Of Riparian Forests, Platte River, Nebraska, 2002–06, Matthew K. Landon, David L. Rus, Benjamin J. Dietsch, Michaela R. Johnson, Kathleen D. Eggemeyer Jan 2008

Evapotranspiration Rates Of Riparian Forests, Platte River, Nebraska, 2002–06, Matthew K. Landon, David L. Rus, Benjamin J. Dietsch, Michaela R. Johnson, Kathleen D. Eggemeyer

United States Geological Survey: Publications

Evapotranspiration (ET) in riparian areas is a poorly understood component of the regional water balance in the Platte River Basin, where competing demands have resulted in water shortages in the ground-water/surface-water system. From April 2002 through March 2006, the U.S. Geological Survey, Nebraska Platte River Cooperative Hydrology Study Group, and Central Platte Natural Resources District conducted a micrometeorological study of water and energy balances at two sites in central Nebraska near Odessa and Gothenburg to improve understanding of ET rates and factors affecting them in Platte River riparian forests. A secondary objective of the study was to constrain estimates of …

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Range-Wide Patterns Of Greater Sage-Grouse Persistence, Cameron L. Aldridge, Scott E. Nielsen, Hawthorne L. Beyer, Mark S. Boyce, John W. Connelly, Steven T. Knick, Michael A. Schroeder Jan 2008

Range-Wide Patterns Of Greater Sage-Grouse Persistence, Cameron L. Aldridge, Scott E. Nielsen, Hawthorne L. Beyer, Mark S. Boyce, John W. Connelly, Steven T. Knick, Michael A. Schroeder

United States Geological Survey: Staff Publications

Aim
Greater sage-grouse (Centrocercus urophasianus), a shrub-steppe obligate species of western North America, currently occupies only half its historical range. Here we examine how broad-scale, long-term trends in landscape condition have affected range contraction.

Location
Sagebrush biome of the western USA.

Methods
Logistic regression was used to assess persistence and extirpation of greater sage-grouse range based on landscape conditions measured by human population (density and population change), vegetation (percentage of sagebrush habitat), roads (density of and distance to roads), agriculture (cropland, farmland and cattle density), climate (number of severe and extreme droughts) and range periphery. Model predictions were …

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Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa, Erin Muths, David S. Pilliod, Lauren J. Livo Jan 2008

Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa, Erin Muths, David S. Pilliod, Lauren J. Livo

United States Geological Survey: Staff Publications

Amphibian populations continue to be imperiled by the chytrid fungus (Batrachochytrium dendrobatidis). Understanding where B. dendrobatidis (Bd) occurs and how it may be limited by environmental factors is critical to our ability to effectively conserve the amphibians affected by Bd. We sampled 1247 amphibians (boreal toads and surrogates) at 261 boreal toad (Bufo boreas) breeding sites (97 clusters) along an 11° latitudinal gradient in the Rocky Mountains to determine the distribution of B. dendrobatidis and examine environmental factors, such as temperature and elevation, that might affect its distribution. The fungus was detected at …

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Corrigendum To ‘‘Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa’’ [Biological Conservation 141 (2008) 1484–1492], Erin Muths, David S. Pilliod, Lauren J. Livo Jan 2008

Corrigendum To ‘‘Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa’’ [Biological Conservation 141 (2008) 1484–1492], Erin Muths, David S. Pilliod, Lauren J. Livo

United States Geological Survey: Staff Publications

The author regrets that in the above published paper the following error occurred:
In our recently published paper, ‘‘Distribution and environmental limitations of an amphibian pathogen in the Rocky Mountains, USA’’, we erroneously included the paper by J. Bosch et al. (2006), ‘‘Climate change and outbreaks of amphibian chytridiomycosis in a montane area of Central Spain: is there a link?’’ in a list of studies from the tropics. Clearly Dr. Bosch and colleagues worked in the temperate zone at a latitude very similar to that in our study suggesting that further investigation of additional similarities between the two sites might …

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Paleoclimatic Significance Of Chemical Weathering In Loess-Derived Paleosols Of Subarctic Central Alaska, Daniel R. Muhs, Thomas A. Ager, Gary Skipp, Jossh Beann, James Budahn, John P. Mcgeehin Jan 2008

Paleoclimatic Significance Of Chemical Weathering In Loess-Derived Paleosols Of Subarctic Central Alaska, Daniel R. Muhs, Thomas A. Ager, Gary Skipp, Jossh Beann, James Budahn, John P. Mcgeehin

United States Geological Survey: Staff Publications

Chemical weathering in soils has not been studied extensively in high-latitude regions. Loess sequences with modern soils and paleosols are present in much of subarctic Alaska, and allow an assessment of present and past chemical weathering. Five sections were studied in detail in the Fairbanks, Alaska, area. Paleosols likely date to mid-Pleistocene interglacials, the last interglacial, and early-to-mid- Wisconsin interstadials. Ratios of mobile (Na, Ca, Mg, Si) to immobile (Ti or Zr) elements indicate that modern soils and most interstadial and interglacial paleosols are characterized by significant chemical weathering. Na2O/TiO2 is lower in modern soils and most …

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Pesticide Fate And Transport Throughout Unsaturated Zones In Five Agricultural Settings, Usa, Tracy C. Hancock, Mark W. Sandstrom, Jason R. Vogel, Richard M.T. Webb, E. Randall Bayless, Jack E. Barbash Jan 2008

Pesticide Fate And Transport Throughout Unsaturated Zones In Five Agricultural Settings, Usa, Tracy C. Hancock, Mark W. Sandstrom, Jason R. Vogel, Richard M.T. Webb, E. Randall Bayless, Jack E. Barbash

United States Geological Survey: Staff Publications

Pesticide transport through the unsaturated zone is a function of chemical and soil characteristics, application, and water recharge rate. The fate and transport of 82 pesticides and degradates were investigated at five different agricultural sites. Atrazine and metolachlor, as well as several of the degradates of atrazine, metolachlor, acetochlor, and alachlor, were frequently detected in soil water during the 2004 growing season, and degradates were generally more abundant than parent compounds. Metolachlor and atrazine were applied at a Nebraska site the same year as sampling, and focused recharge coupled with the short time since application resulted in their movement in …

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Developing Conceptual Hydrogeological Model For Potsdam Sandstones In Southwestern Quebec, Canada, M. Nastev, Roger H. Morin, R. Godin, A. Rouleau Jan 2008

Developing Conceptual Hydrogeological Model For Potsdam Sandstones In Southwestern Quebec, Canada, M. Nastev, Roger H. Morin, R. Godin, A. Rouleau

United States Geological Survey: Staff Publications

A hydrogeological study was conducted in Potsdam sandstones on the international border between Canada (Quebec) and the USA (New York). Two sandstone formations, arkose and conglomerate (base) and well-cemented quartz arenite (upper), underlie the study area and form the major regional aquifer unit. Glacial till, littoral sand and gravel, and marine silt and clay discontinuously overlie the aquifer. In both sandstone formations, sub-horizontal bedding planes are ubiquitous and display significant hydraulic conductivities that are orders of magnitude more permeable than the intact rock matrix. Aquifer tests demonstrate that the two formations have similar bulk hydrologic properties, with average hydraulic conductivities …

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Late-Seasonal A Ctivity And Diet Of The Eveninc Bat (Nycticeius Humeralis) In Nebraska, Keith Geluso, Jason P. Damm, Ernest W. Valdez Jan 2008

Late-Seasonal A Ctivity And Diet Of The Eveninc Bat (Nycticeius Humeralis) In Nebraska, Keith Geluso, Jason P. Damm, Ernest W. Valdez

United States Geological Survey: Staff Publications

In North America, Nebraska represents part of the northwestern edge of the distribution for the evening bat (Nycticeius humeralis). To date, little information on this bat’s natural history has been published from the state or from other parts of the Great Plains. Here we report on aspects of its natural history in Nebraska from 2 localities. In late summer and early autumn of 2006, we documented individuals farther west in Nebraska (Harlan County) than previously reported and determined that individuals fed mainly on Coleoptera and Hymenoptera. In 2006, evening bats appeared to migrate from Nebraska during late September–early …

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Sacramento-San Joaquin Delta Regional Ecosystem Restoration Implementation Plan, Charles N. Alpers, Collin Eagles-Smith, Chris Foe, Susan Klasing, Mark C. Marvin-Dipasquale, Darell G. Slotton, Lisamarie Windham-Myers Jan 2008

Sacramento-San Joaquin Delta Regional Ecosystem Restoration Implementation Plan, Charles N. Alpers, Collin Eagles-Smith, Chris Foe, Susan Klasing, Mark C. Marvin-Dipasquale, Darell G. Slotton, Lisamarie Windham-Myers

United States Geological Survey: Staff Publications

Mercury has been identified as an important contaminant in the Delta, based on elevated concentrations of methylmercury (a toxic, organic form that readily bioaccumulates) in fish and wildlife. There are health risks associated with human exposure to methylmercury by consumption of sport fish, particularly top predators such as bass species. Original mercury sources were upstream tributaries where historical mining of mercury in the Coast Ranges and gold in the Sierra Nevada and Klamath-Trinity Mountains caused contamination of water and sediment on a regional scale. Remediation of abandoned mine sites may reduce local sources in these watersheds, but much of the …

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Development And Evaluation Of Geochemical Methods For The Sourcing Of Archaeological Maize, L.V. Benson, H. E. Taylor, K.A. Peterson, B.D. Shattuck, C.A. Ramotnik, J.R. Stein Jan 2008

Development And Evaluation Of Geochemical Methods For The Sourcing Of Archaeological Maize, L.V. Benson, H. E. Taylor, K.A. Peterson, B.D. Shattuck, C.A. Ramotnik, J.R. Stein

United States Geological Survey: Staff Publications

Strontium (Sr)-isotope values on bone from deer mice pairs from 12 field sites in the Chaco Canyon area, New Mexico, were compared with isotope values of synthetic soil waters from the same fields. The data indicate that mice obtain Sr from near-surface sources and that soil samples collected at depths ranging from 25 to 95 cm contain Sr that is more accessible to the deep roots of maize; thus, synthetic soil solutions provide better data for the sourcing of archaeological maize. However, the Sr-isotope composition of mice may be more valuable in sourcing archaeological remains of animals such as rabbit, …

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Tools And Technology Article: Estimation And Correction Of Visibility Bias In Aerial Surveys Of Wintering Ducks, Aaron T. Pearse, Patrick D. Gerard, Stephen J. Dinsmore, Richard M. Kaminski, Kenneth J. Reinecke Jan 2008

Tools And Technology Article: Estimation And Correction Of Visibility Bias In Aerial Surveys Of Wintering Ducks, Aaron T. Pearse, Patrick D. Gerard, Stephen J. Dinsmore, Richard M. Kaminski, Kenneth J. Reinecke

United States Geological Survey: Staff Publications

Incomplete detection of all individuals leading to negative bias in abundance estimates is a pervasive source of error in aerial surveys of wildlife, and correcting that bias is a critical step in improving surveys. We conducted experiments using duck decoys as surrogates for live ducks to estimate bias associated with surveys of wintering ducks in Mississippi, USA. We found detection of decoy groups was related to wedand cover type (open vs. forested), group size (1-100 decoys), and interaction of these variables. Observers who detected decoy groups reported counts that averaged 78% of the decoys actually present, and this counting bias …

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Relations Between And Among Contaminant Concentrations And Biomarkers In Black Bass (Micropterus Spp.) And Common Carp (Cyprinus Carpio) From Large U.S. Rivers, 1995–2004, Jo Ellen Hinck, Christopher J. Schmitt, Mark R. Ellersieck, Donald E. Tillitt Jan 2008

Relations Between And Among Contaminant Concentrations And Biomarkers In Black Bass (Micropterus Spp.) And Common Carp (Cyprinus Carpio) From Large U.S. Rivers, 1995–2004, Jo Ellen Hinck, Christopher J. Schmitt, Mark R. Ellersieck, Donald E. Tillitt

United States Geological Survey: Staff Publications

Environmental contaminant and biomarker monitoring data from major U.S. river basins were summarized for black bass (Micropterus spp.) and common carp (Cyprinus carpio) sampled over a nine year period. Cumulative frequency distributions revealed taxon differences for many organochlorine residue concentrations, elemental contaminant concentrations, and biomarkers, but few gender differences were evident for chemical concentrations. Concentrations of dacthal, pentachloroanisole, p,p'-DDE, endosulfan sulfate, barium, cadmium, copper, manganese, lead, selenium, vanadium, and zinc were greater in carp than bass, but concentrations of mercury and magnesium were greater in bass. Gender differences were evident in bass for mercury and in carp …

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Downflow Limestone Beds For Treatment Of Net-Acidic, Oxic, Iron-Laden Drainage From A Flooded Anthracite Mine, Pennsylvania, Usa: 2. Laboratory Evaluation, Charles A. Cravotta Iii, Suzanne J. Ward, Jane M. Hammarstrom Jan 2008

Downflow Limestone Beds For Treatment Of Net-Acidic, Oxic, Iron-Laden Drainage From A Flooded Anthracite Mine, Pennsylvania, Usa: 2. Laboratory Evaluation, Charles A. Cravotta Iii, Suzanne J. Ward, Jane M. Hammarstrom

United States Geological Survey: Staff Publications

Acidic mine drainage (AMD) containing elevated concentrations of dissolved iron and other metals can be neutralized to varying degrees by reactions with limestone in passive treatment systems. We evaluated the chemical and mineralogical characteristics and the effectiveness of calcitic and dolomitic limestone for the neutralization of net-acidic, oxic, iron-laden AMD from a flooded anthracite mine. The calcitic limestone, with CaCO3 and MgCO3 contents of 99.8 and <0.1 wt%, respectively, and the dolomitic limestone, with CaCO3 and MgCO3 contents of 60.3 and 40.2 wt%, were used to construct a downflow treatment system in 2003 at the Bell Mine, a large source of AMD and baseflow to …

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