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University of Nebraska - Lincoln

2005

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Articles 1 - 30 of 100

Full-Text Articles in Earth Sciences

Cornhusker Army Ammunition Plant Nebraska, Bryant Burnett, Karla Asberry Dec 2005

Cornhusker Army Ammunition Plant Nebraska, Bryant Burnett, Karla Asberry

United States Environmental Protection Agency: Staff Publications

The 19-square mile Cornhusker Army Ammunition Plant is a former U.S. Army Armament, Munitions, and Chemical Command facility. On standby status since 1973, the operation leases land for agriculture, grazing, and wildlife management activities. The plant was built in 1942 to produce munitions and provide support functions during World War II. It has been in and out of production over the years. The plant consists of five main components: five major production areas where munitions were loaded, assembled, and packed; a fertilizer manufacturer; two major storage facilities; a sanitary landfill; and a burning ground where materials contaminated with explosives were …

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Results Of Vadose Zone Sampling Within The Tri-Basin Natural Resources District, Mark E. Burbach Nov 2005

Results Of Vadose Zone Sampling Within The Tri-Basin Natural Resources District, Mark E. Burbach

Conservation and Survey Division

No abstract provided.

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Mountain Plover Population Responses To Black-Tailed Prairie Dogs In Montana, Stephen J. Dinsmore, Gary C. White, Fritz L. Knopf Oct 2005

Mountain Plover Population Responses To Black-Tailed Prairie Dogs In Montana, Stephen J. Dinsmore, Gary C. White, Fritz L. Knopf

United States Geological Survey: Staff Publications

We studied a local population of mountain plovers (Charadrius montanus) in southern Phillips County, Montana, USA, from 1995 to 2000 to estimate annual rates of recruitment rate (f) and population change (λ). We used Pradel models, and we modeled λ as a constant across years, as a linear time trend, as year-specific, and with an additive effect of area occupied by prairie dogs (Cynomys ludovicianus). We modeled recruitment rate (f) as a function of area occupied by prairie dogs with the remaining model structure identical to the best model used to estimate λ. Our results indicated …

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Nonlinear Dynamics In Ecosystem Response To Climatic Change: Case Studies And Policy Implications, Virginia R. Burkett, Douglas A. Wilcox, Wilcox Stottlemyer, Wylie Barrow, Dan Fagre, Jill Baron, Jeff Price, Jennifer L. Nielsen, Craig D. Allen, David L. Peterson, Greg Ruggerone, Thomas Doyle Sep 2005

Nonlinear Dynamics In Ecosystem Response To Climatic Change: Case Studies And Policy Implications, Virginia R. Burkett, Douglas A. Wilcox, Wilcox Stottlemyer, Wylie Barrow, Dan Fagre, Jill Baron, Jeff Price, Jennifer L. Nielsen, Craig D. Allen, David L. Peterson, Greg Ruggerone, Thomas Doyle

United States Geological Survey: Staff Publications

Many biological, hydrological, and geological processes are interactively linked in ecosystems. These ecological phenomena normally vary within bounded ranges, but rapid, nonlinear changes to markedly different conditions can be triggered by even small differences if threshold values are exceeded. Intrinsic and extrinsic ecological thresholds can lead to effects that cascade among systems, precluding accurate modeling and prediction of system response to climate change. Ten case studies from North America illustrate how changes in climate can lead to rapid, threshold-type responses within ecological communities; the case studies also highlight the role of human activities that alter the rate or direction of …

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Cloud-To-Ground Lightning Production In Strongly Forced, Low-Instability Convective Lines Associated With Damaging Wind, Matthew S. Van Den Broeke, David M. Schultz, Robert H. Johns, Jeffry S. Evans, John E. Hales Aug 2005

Cloud-To-Ground Lightning Production In Strongly Forced, Low-Instability Convective Lines Associated With Damaging Wind, Matthew S. Van Den Broeke, David M. Schultz, Robert H. Johns, Jeffry S. Evans, John E. Hales

Department of Earth and Atmospheric Sciences: Faculty Publications

During 9–11 November 1998 and 9–10 March 2002, two similar convective lines moved across the central and eastern United States. Both convective lines initiated over the southern plains along strong surface-based cold fronts in moderately unstable environments. Both lines were initially associated with cloud-to-ground (CG) lightning, as detected by the National Lightning Detection Network, and both events met the criteria to be classified as derechos, producing swaths of widespread damaging wind. After moving into areas of marginal, if any, instability over the upper Midwest, CG lightning production ceased or nearly ceased, although the damaging winds continued. The 9 March 2002 …

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Factors Affecting Songbird Nest Survival And Brood Parasitism In The Rainwater Basin Region Of Nebraska, Max Post Van Der Burg Aug 2005

Factors Affecting Songbird Nest Survival And Brood Parasitism In The Rainwater Basin Region Of Nebraska, Max Post Van Der Burg

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

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The Impacts Of Sprawl On Biodiversity: The Ant Fauna Of The Lower Florida Keys, Elizabeth A. Forys, Craig R. Allen Aug 2005

The Impacts Of Sprawl On Biodiversity: The Ant Fauna Of The Lower Florida Keys, Elizabeth A. Forys, Craig R. Allen

United States Geological Survey: Staff Publications

Sprawling development can affect species composition by increasing the rate of invasion by non-native species, and decreasing the persistence of native species. This paper briefly reviews the scientific literature on the impacts of sprawl on biological diversity, with specific emphasis on the influence of sprawl on non-native species richness. We then explore the relationship between sprawl and biodiversity using a data set of ant species collected from 46 habitat patches located in the increasingly suburbanized Florida Keys, USA. We quantified sprawl as the proximity of roads and amount of development surrounding a habitat patch. Using bait transects, we identified 24 …

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Age And Quality Of Ground Water And Sources Of Nitrogen In The Surficial Aquifers In Pumpkin Creek Valley, Western Nebraska, 2000, G. V. Steele, J. C. Cannia, S. S. Sibray, V. L. Mcguire Aug 2005

Age And Quality Of Ground Water And Sources Of Nitrogen In The Surficial Aquifers In Pumpkin Creek Valley, Western Nebraska, 2000, G. V. Steele, J. C. Cannia, S. S. Sibray, V. L. Mcguire

Publications of the US Geological Survey

Ground water is the source of drinking water for the residents of Pumpkin Creek Valley, western Nebraska. In this largely agricultural area, shallow aquifers potentially are susceptible to nitrate contamination. During the last 10 years, ground-water levels in the North Platte Natural Resources District have declined and contamination has become a major problem for the district. In 2000, the U.S. Geological Survey and the North Platte Natural Resources District began a cooperative study to determine the age and quality of the ground water and the sources of nitrogen in the aquifers in Pumpkin Creek Valley.

Water samples were collected from …

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Reply To Comment By Sushil K. Singh On "A Concept Of Maximum Stream Depletion Rate For Leaky Aquifers In Alluvial Valleys", Vitaly A. Zlotnik Aug 2005

Reply To Comment By Sushil K. Singh On "A Concept Of Maximum Stream Depletion Rate For Leaky Aquifers In Alluvial Valleys", Vitaly A. Zlotnik

Department of Earth and Atmospheric Sciences: Faculty Publications

Vitaly A. Zlotnik's reply to the comment by Sushil K. Singh on Zlotnik's "A concept of maximum stream depletion rate for leaky aquifers in alluvial valleys."

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Distribution Patterns Of Lentic-Breeding Amphibians In Relation To Ultraviolet Radiation Exposure In Western North America, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Paul Stephen Corn, Stephen A. Diamond, Peter C. Trenham, Dan B. Fagre Jul 2005

Distribution Patterns Of Lentic-Breeding Amphibians In Relation To Ultraviolet Radiation Exposure In Western North America, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Paul Stephen Corn, Stephen A. Diamond, Peter C. Trenham, Dan B. Fagre

United States Geological Survey: Staff Publications

An increase in ultraviolet-B (UV-B) radiation has been posited to be a potential factor in the decline of some amphibian population. This hypothesis has received support from laboratory and field experiments showing that current levels of UV-B can cause embryo mortality in some species, but little research has addressed whether UV-B is influencing the distribution of amphibian populations. We compared patterns of amphibian presence to sitespecific estimates of UV-B dose at 683 ponds and lakes in Glacier, Olympic, and Sequoia–Kings Canyon National Parks. All three parks are located in western North America, a region with a concentration of documented amphibian …

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Estimated Ultraviolet Radiation Doses In Wetlands In Six National Parks, Stephen A. Diamond, Peter C. Trenham, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Stacey L. Stark, David Bradford, P. Stephen Corn, Ken Czarnowski, Paul D. Brooks, Dan Fagre, Bob Breen, Naomi E. Detenbeck, Kathy Tonnessen Jul 2005

Estimated Ultraviolet Radiation Doses In Wetlands In Six National Parks, Stephen A. Diamond, Peter C. Trenham, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Stacey L. Stark, David Bradford, P. Stephen Corn, Ken Czarnowski, Paul D. Brooks, Dan Fagre, Bob Breen, Naomi E. Detenbeck, Kathy Tonnessen

United States Geological Survey: Staff Publications

Ultraviolet-B radiation (UV-B, 280–320-nm wavelengths) doses were estimated for 1024 wetlands in six national parks: Acadia (Acadia), Glacier (Glacier), Great Smoky Mountains (Smoky), Olympic (Olympic), Rocky Mountain (Rocky), and Sequoia/ Kings Canyon (Sequoia). Estimates were made using ground-based UV-B data (Brewer spectrophotometers), solar radiation models, GIS tools, field characterization of vegetative features, and quantification of DOC concentration and spectral absorbance. UV-B dose estimates were made for the summer solstice, at a depth of 1 cm in each wetland. The mean dose across all wetlands and parks was 19.3 W-h m-2 (range of 3.4–32.1 W-h m-2). The mean …

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Holocene Hydrologic Variation At Lake Titicaca, Bolivia/Peru, And Its Relationship To North Atlantic Climate Variation, P. A. Baker, Sherilyn C. Fritz, J. Garland, E. Ekdahl Jul 2005

Holocene Hydrologic Variation At Lake Titicaca, Bolivia/Peru, And Its Relationship To North Atlantic Climate Variation, P. A. Baker, Sherilyn C. Fritz, J. Garland, E. Ekdahl

Department of Earth and Atmospheric Sciences: Faculty Publications

A growing number of sites in the Northern Hemisphere show centennial- to millennial-scale climate variation that has been correlated with change in solar variability or with change in North Atlantic circulation. However, it is unclear how (or whether) these oscillations in the climate system are manifest in the Southern Hemisphere because of a lack of sites with suitably high sampling resolution. In this paper, we reconstruct the lake-level history of Lake Titicaca, using the carbon isotopic content of sedimentary organic matter, to evaluate centennial-to millennial-scale precipitation variation and its phasing relative to sites in the Northern Hemisphere. The pattern and …

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Water Quality Trading: What Can We Learn From 10 Years Of Wetland Mitigation Banking?, Eric Raffini, Morgan Robertson Jul 2005

Water Quality Trading: What Can We Learn From 10 Years Of Wetland Mitigation Banking?, Eric Raffini, Morgan Robertson

United States Environmental Protection Agency: Staff Publications

In 2003 the U.S. Environmental Protection Agency issued its Water Quality Trading Policy. Water quality trading allows facilities facing high pollution-control costs to meet their regulatory requirements by purchasing environmentally equivalent or superior pollution reductions from another source, often at a lower cost. The policy, which hopes to achieve "water quality and environmental benefits greater than would otherwise be achieved under more traditional regulatory approaches," established the ground rules for trading and encourages states, interstate agencies, and tribes to develop and implement water quality trading programs for nutrients, sediments, and other pollutants. The policy generated controversy among some stakeholder groups; …

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Andrill Mcmurdo Ice Shelf Project Scientific Prospectus, Timothy R. Naish, Ross D. Powell, Peter J. Barrett, Huw Horgan, Gavin B. Dunbar, Gary S. Wilson, Richard Levy, Natalie Robinson, L. Carter, Alex R. Pyne, Frank Niessen, Stephen Bannister, Natalie Balfour, Detlef Damaske, Stuart Henrys, Phil Kyke, Terry Wilson Jun 2005

Andrill Mcmurdo Ice Shelf Project Scientific Prospectus, Timothy R. Naish, Ross D. Powell, Peter J. Barrett, Huw Horgan, Gavin B. Dunbar, Gary S. Wilson, Richard Levy, Natalie Robinson, L. Carter, Alex R. Pyne, Frank Niessen, Stephen Bannister, Natalie Balfour, Detlef Damaske, Stuart Henrys, Phil Kyke, Terry Wilson

ANDRILL Project Information

Response of Antarctic ice sheets to projected greenhouse warming of up to 5.8!C by the end of the century is not known. Models on which predictions are based need to be constrained by geological data of the ancient ice sheets during times when Earth is known to have been warmer than today. The marine-based West Antarctic Ice Sheet (WAIS) and its fringing ice shelves are hypothesized (Clark et al., 2002; Weaver et al., 2003; Stocker, 2003) and documented (Scherer et al., 1998) to have collapsed during past “super-interglacial” warm extremes when global sea-level was more than 5m higher than today. …

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Aquitard Effect On Drawdown In Water Table Aquifers, Vitaly A. Zlotnik, Hongbin Zhan Jun 2005

Aquitard Effect On Drawdown In Water Table Aquifers, Vitaly A. Zlotnik, Hongbin Zhan

Department of Earth and Atmospheric Sciences: Faculty Publications

The effects of an aquitard on drawdown in an overlying unconfined aquifer can be represented by a drainage-type term at the aquitard-aquifer interface. The functional form of this boundary condition is similar to the Boulton-Neuman boundary condition used for water table aquifers except the kernel contains an inverse square root of time instead of a negative exponential. Type curves using the new boundary condition were obtained in semianalytical form. Examples for several representative conditions show that the effect of the underlying aquitard can contribute to the type curve at early and intermediate times, but the effect becomes negligible at late …

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Comparison Of Preconstruction And 2003 Bathymetric And Topographic Surveys Of Lake Mcconaughy, Nebraska, W. H. Kress, S. K. Sebree, G. R. Littin, M. A. Drain, M. E. Kling May 2005

Comparison Of Preconstruction And 2003 Bathymetric And Topographic Surveys Of Lake Mcconaughy, Nebraska, W. H. Kress, S. K. Sebree, G. R. Littin, M. A. Drain, M. E. Kling

Publications of the US Geological Survey

The U.S. Geological Survey, in cooperation with The Central Nebraska Public Power and Irrigation District, conducted a study that used bathymetric and topographic surveying in conjunction with Geographical Information Systems techniques to determine the 2003 physical shape, current storage capacity, and the changes in storage capacity of Lake McConaughy that have occurred over the past 62 years. By combining the bathymetric and topographic survey data, the current surface area of Lake McConaughy was determined to be 30,413.0 acres, with a volume of 1,756,300 acre-feet at the lake conservation-pool elevation of 3,266.4 feet above North American Vertical Datum of 1988 (3,265.0 …

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Andrill Southern Mcmurdo Sound Project Scientific Prospectus, David M. Harwood, Fabio Florindo, Richard H. Levy, Christopher R. Fielding, Stephen F. Pekar, M. A. Speece, Sms Science Team, Andrill Science Management Office May 2005

Andrill Southern Mcmurdo Sound Project Scientific Prospectus, David M. Harwood, Fabio Florindo, Richard H. Levy, Christopher R. Fielding, Stephen F. Pekar, M. A. Speece, Sms Science Team, Andrill Science Management Office

ANDRILL Project Information

During the austral summer of 2007 the ANtarctic DRILLing program (ANDRILL) will drill from a sea-ice platform in southern McMurdo Sound to obtain new information about the Neogene Antarctic cryosphere and evolution of Antarctic rift basins.

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Adoption Of Riparian Forest Buffers On Private Lands In Nebraska, Usa, Peter Skelton, Scott J. Josiah, James W. King, James R. Brandle, Glenn A. Helmers, Charles A. Francis Apr 2005

Adoption Of Riparian Forest Buffers On Private Lands In Nebraska, Usa, Peter Skelton, Scott J. Josiah, James W. King, James R. Brandle, Glenn A. Helmers, Charles A. Francis

Department of Agricultural Leadership, Education, and Communication: Faculty Publications

Pesticide and nutrient runoff from agricultural fields is a socio-environmental problem in the Midwestern United States. Riparian forest buffers (RFBs) are a proven conservation practice that effectively manage this problem, though adoption rates are low. A mail survey was conducted to determine differences between adopter and nonadopter characteristics and attitudes with regard to the use of RFBs. Data were collected from 48 RFB adopters and 261 RFB nonadopters in two Nebraska watersheds. Inferential and multivaririate statistics were used to identify differences between adapter status and producer status groups. About half (50.8%) the respondents were nonproducers. Nonproducers are agricultural landowners not …

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Patterns Of Fish Use And Piscivore Abundance Within A Reconnected Saltmarsh Impoundment In The Northern Indian River Lagoon, Florida, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak Apr 2005

Patterns Of Fish Use And Piscivore Abundance Within A Reconnected Saltmarsh Impoundment In The Northern Indian River Lagoon, Florida, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Nearly all saltmarshes in east-central, Florida were impounded for mosquito control during the 1960s. The majority of these marshes have since been reconnected to the estuary by culverts, providing an opportunity to effectively measure exchange of aquatic organisms. A multi-gear approach was used monthly to simultaneously estimate fish standing stock (cast net), fish exchange with the estuary (culvert traps), and piscivore abundance (gill nets and bird counts) to document patterns of fish use in a reconnected saltmarsh impoundment. Changes in saltmarsh fish abundance, and exchange of fish with the estuary reflected the seasonal pattern of marsh flooding in the northern …

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Lack Of Significant Changes In The Herpetofauna Of Theodore Roosevelt National Park, North Dakota, Since The 1920s, Blake R. Hossack, Paul Stephen Corn, David S. Pilliod Apr 2005

Lack Of Significant Changes In The Herpetofauna Of Theodore Roosevelt National Park, North Dakota, Since The 1920s, Blake R. Hossack, Paul Stephen Corn, David S. Pilliod

United States Geological Survey: Staff Publications

We surveyed 88 upland wetlands and 12 1-km river sections for amphibians in Theodore Roosevelt National Park, North Dakota, during 2001–2002 to gather baseline data for future monitoring efforts and to evaluate changes in the distribution of species. We compared our results to collections of herpetofauna made during 1920–1922, 1954 and 1978–1979. The boreal chorus frog (Pseudacris maculata) was the most common amphibian in upland wetlands, followed by the tiger salamander (Ambystoma tigrinum), Woodhouse’s toad (Bufo woodhousii), northern leopard frog (Rana pipiens), plains spadefoot (Spea bombifrons) and the Great Plains …

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Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree Apr 2005

Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree

United States Geological Survey: Staff Publications

In Nebraska, a large number (>200) of shallow sand-point and cased wells completed in coarse alluvial sediments along rivers and lakes still are used to obtain drinking water for human consumption, even though construction of sand-point wells for consumptive uses has been banned since 1987. The quality of water from shallow domestic wells potentially vulnerable to seepage from septic systems was evaluated by analyzing for the presence of tracers and multiple isotopes. Samples were collected from 26 sand-point and perforated, cased domestic wells and were analyzed for bacteria, coliphages, nitrogen species, nitrogen and boron isotopes, dissolved organic carbon (DOC), …

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Evidence Of Holocene Climate Change In A Nebraska Sandhills Wetland, Barbara Nicholson, James B. Swinehart Apr 2005

Evidence Of Holocene Climate Change In A Nebraska Sandhills Wetland, Barbara Nicholson, James B. Swinehart

Great Plains Research: A Journal of Natural and Social Sciences

The Nebraska Sandhills consist of 50,000 km2 of dunes, currently stabilized by vegetation. Radiocarbon dates of paleosols, blocked paleovalleys, and sand beds found in interdunal wetlands suggest that the Holocene had significant periods of dune reactivation. A paleoecological investigation was conducted in Jumbo Valley, NE, in an interdunal wetland known to contain sand layers interbedded with peat. The sedimentary record in two cores is continuous, except for some loss due to surficial burns. Macrofossils indicate that the late Pleistocene was cool and wet, with current vegetation establishing around 12,000 years ago. Sand and bulk density profiles reveal significant periods …

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The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak Mar 2005

The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The existing scientific literature on offshore benthic assemblages (OBA) residing along the US East and Gulf of Mexico continental shelf was reviewed. Identification was made of any associations between the dominant OBA and particular sediment types and/or bathymetry. Of special interest was the evaluation of reported effects of sand dredge/mining activities on the dominant OBA and recognition of data deficiencies. One hundred and twenty-two references were selected and classified as to type of study with pertinent results extracted. Polychaetes were predominantly cited as the principal infaunal taxa present in studies from both the Gulf of Mexico and US Atlantic coast. …

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Evaluation Of Models And Data For Assessing Whooping Crane Habitat In The Central Platte River, Nebraska, Adrian H. Farmer, Brian S. Cade, James W. Terrell, Jim H. Henriksen, Jeffery T. Runge Mar 2005

Evaluation Of Models And Data For Assessing Whooping Crane Habitat In The Central Platte River, Nebraska, Adrian H. Farmer, Brian S. Cade, James W. Terrell, Jim H. Henriksen, Jeffery T. Runge

United States Geological Survey: Water Reports and Publications

The primary objectives of this evaluation were to improve the performance of the Whooping Crane Habitat Suitability model (C4R) used by the U.S. Fish and Wildlife Service (Service) for defining the relationship between river discharge and habitat availability, and to assist the Service in implementing improved model(s) with existing hydraulic files. The C4R habitat model is applied at the scale of individual river cross-sections, but the model outputs are scaled-up to larger reaches of the river using a decision support “model” comprised of other data and procedures. Hence, the validity of the habitat model depends at least partially on how …

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Women In Oceanography: Women Of The Academy And The Sea, Suzanne O'Connell, Mary Anne Holmes Mar 2005

Women In Oceanography: Women Of The Academy And The Sea, Suzanne O'Connell, Mary Anne Holmes

Department of Earth and Atmospheric Sciences: Faculty Publications

Women have played an active role in all areas of oceanography. Defining the number of women oceanographers is not an easy task because the discipline is so broad and the boundaries between subdisciplines are not always distinct.

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Vertical Movement Of Water In A High Plains Aquifer Induced By A Pumping Well, Xunhong Chen, Yanfeng Yin, James W. Goeke, Robert F. Diffendal Jr. Feb 2005

Vertical Movement Of Water In A High Plains Aquifer Induced By A Pumping Well, Xunhong Chen, Yanfeng Yin, James W. Goeke, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Field observation and numerical simulations were carried out to evaluate the hydraulic relationship between the shallow and deep aquifer of a High Plains Aquifer system, in which shallow and deep aquifers are separated by an aquitard. Pumping from the lower aquifer resulted in a small drawdown in the upper aquifer and a larger drawdown in the aquitard; pumping from the shallow aquifer caused a small drawdown in the aquitard and the deep aquifer. Analysis of pumping test data gives the values of the hydraulic conductivity of the aquitard and the deep aquifer. Long-term observation of groundwater levels in the shallow …

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The Maastrichtian Record From Shatsky Rise (Northwest Pacific): A Tropical Perspective On Global Ecological And Oceanographic Changes, Tracy D. Frank, Deborah J. Thomas, R. Mark Leckie, Michael A. Arthur, Paul R. Brown, Kelly Jones, Jackie A. Lees Feb 2005

The Maastrichtian Record From Shatsky Rise (Northwest Pacific): A Tropical Perspective On Global Ecological And Oceanographic Changes, Tracy D. Frank, Deborah J. Thomas, R. Mark Leckie, Michael A. Arthur, Paul R. Brown, Kelly Jones, Jackie A. Lees

Department of Earth and Atmospheric Sciences: Faculty Publications

We present new isotopic and micropaleontological data from a depth transect on Shatsky Rise that record the response of the tropical Pacific to global biotic and oceanographic shifts during the mid-Maastrichtian. Results reveal a coupling between the upper ocean, characterized by a weak thermocline and low to intermediate productivity, and intermediate waters. During the earliest Maastrichtian, oxygen and neodymium isotope data suggest a significant contribution of relatively warm intermediate water from the North Pacific. Isotopic shifts through the early Maastrichtian suggest that this warmer water mass was gradually replaced by cooler waters originating in the Southern Ocean. Although the cooler …

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Groundwater Irrigation In The Development Of The Grand Prairie Rice Industry, 1896-1950, John B. Gates Jan 2005

Groundwater Irrigation In The Development Of The Grand Prairie Rice Industry, 1896-1950, John B. Gates

Department of Earth and Atmospheric Sciences: Faculty Publications

Elucidates some of the ways in which groundwater and groundwater irrigation have affected the Grand Prairie's rice industry over time and conversely how the development of the industry has altered the region's groundwater conditions. Concentrates on aspects of the industry's history that have often been overlooked in favor of rice cultivation's social dimensions and consider hydrological systems not just as resources awaiting exploitation or as simple constraints on production but as variables whose roles and effects can change over time.

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Evidence For Marine Influence On A Low-Gradient Coastal Plain: Ichnology And Invertebrate Paleontology Of The Lower Tongue River Member (Fort Union Formation, Middle Paleocene), Western Williston Basin, U.S.A., Edward S. Belt, Neil E. Tibert, H. Allen Curran, John A. Diemer, Joseph H. Hartman, Timothy J. Kroeger, David M. Harwood Jan 2005

Evidence For Marine Influence On A Low-Gradient Coastal Plain: Ichnology And Invertebrate Paleontology Of The Lower Tongue River Member (Fort Union Formation, Middle Paleocene), Western Williston Basin, U.S.A., Edward S. Belt, Neil E. Tibert, H. Allen Curran, John A. Diemer, Joseph H. Hartman, Timothy J. Kroeger, David M. Harwood

Department of Earth and Atmospheric Sciences: Faculty Publications

The Paleocene Tongue River Member of the Fort Union Formation contains trace-fossil associations indicative of marine influence in otherwise freshwater facies. The identified ichnogenera include: Arenicolites, Diplocraterion, Monocraterion, Ophiomorpha, Rhizocorallium, Skolithos linearis, Teichichnus, Thalassinoides, and one form of uncertain affinity. Two species of the marine diatom Coscinodiscus occur a few meters above the base of the member. The burrows occur in at least five discrete, thin, rippled, fine-grained sandstone beds within the lower 85 m of the member west of the Cedar Creek anticline (CCA) in the Signal Butte, Terry Badlands, and Pine Hills areas. T wo discrete burrowed …

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Calcareous Nannofossil Evidence For The Existence Of The Gulf Stream During The Late Maastrichtian, David K. Watkins, Jean M. Self-Trail Jan 2005

Calcareous Nannofossil Evidence For The Existence Of The Gulf Stream During The Late Maastrichtian, David K. Watkins, Jean M. Self-Trail

Department of Earth and Atmospheric Sciences: Faculty Publications

Upper Maastrichtian calcareous nannofossil assemblages, from eight cores on the South Carolina Coastal Plain (onshore set) and three deep sea drilling sites from the continental slope and abyssal hills (offshore set), were analyzed by correlation and principal component analysis to examine the ancient surface water thermal structure. In addition, a temperature index derived from independently published paleobiogeographic information was applied to the sample data. All three methods indicate a strong separation of the samples into onshore and offshore sets, with the offshore data set exhibiting significantly warmer paleotemperatures. The great disparity between these two sample sets indicates that there was …

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