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Distribution Of Dioecious Eastern Red Cedar (Juniperus Virginiana) Along An Environmental Gradient In Ogallala, Ne, Taylor Sloey Apr 2010

Distribution Of Dioecious Eastern Red Cedar (Juniperus Virginiana) Along An Environmental Gradient In Ogallala, Ne, Taylor Sloey

Department of Environmental Studies: Undergraduate Student Theses

Abstract

The purpose of this research was to study the sex distribution and energy allocation of dioecious Eastern Red Cedars (Juniperus virginiana) along an environmental resource gradient. The trees surveyed were growing in a canyon located at the University of Nebraska’s Cedar Point Biological Research Station in Ogallala, Nebraska. Due to the geography of this canyon, environmental factors necessary for plant growth should vary depending on the tree’s location within the canyon. These factors include water availability, sun exposure, ground slope, and soil nitrogen content, all of which are necessary for carbon acquisition.

Juniperus virginiana is a dioecious conifer. Dioecious …


Baseline Rockfall Rates And Rockfall Protection In Virginia, Brian Bruckno Apr 2010

Baseline Rockfall Rates And Rockfall Protection In Virginia, Brian Bruckno

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Current approaches to rockfall hazard and risk mitigation have been dominated by a model in which rockfall is treated as a global slope stability phenomenon which is mainly triggered by precipitation, freeze-thaw, or root wedging. The methods implemented by many public agencies and private entities developed from this conceptualization. These methods, such as the Rockfall Hazard Rating System, Key Block and Key Group Analysis, and remote sensing using LIDAR or digital images, are best applied to the end-members of slopes, such as pure engineered soil or structurally simple and consistent rock slopes. Slopes exhibiting complex structure, slopes that cross formations …


Centers For Renewable Energy & Biomass Utilization, University Of North Dakota. Energy And Environmental Research Center Apr 2010

Centers For Renewable Energy & Biomass Utilization, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Brochure on the Energy & Environmental Research Center's (EERC's) Centers for Renewable Energy & Biomass Utilization, funded in part by the U.S. Department of Energy. Outlines EERC capabilities and the Centers' areas of expertise. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]


Intensity, Magnitude, Location, And Attenuation In India For Felt Earthquakes Since 1762, Walter Szeliga, Susan Hough, Stacey Martin, Roger Bilham Apr 2010

Intensity, Magnitude, Location, And Attenuation In India For Felt Earthquakes Since 1762, Walter Szeliga, Susan Hough, Stacey Martin, Roger Bilham

Faculty Scholarship for the Cascadia Hazards Institute

A comprehensive, consistently interpreted new catalog of felt intensities for India (Martin and Szeliga, 2010, this issue) includes intensities for 570 earthquakes; instrumental magnitudes and locations are available for 100 of these events. We use the intensity values for 29 of the instrumentally recorded events to develop new intensity versus attenuation relations for the Indian subcontinent and the Himalayan region. We then use these relations to determine the locations and magnitudes of 234 historical events, using the method of Bakun and Wentworth (1997). For the remaining 336 events, intensity distributions are too sparse to determine magnitude or location. We evaluate …


A Catalog Of Felt Intensity Data For 570 Earthquakes In India From 1636 To 2009, Stacey Martin, Walter Szeliga Apr 2010

A Catalog Of Felt Intensity Data For 570 Earthquakes In India From 1636 To 2009, Stacey Martin, Walter Szeliga

Faculty Scholarship for the Cascadia Hazards Institute

Eight thousand three hundred thirty-nine intensity observations have been evaluated for earthquakes that occurred on the Indian subcontinent and surrounding plate boundaries from the seventeenth century to the present. They characterize 570 earthquakes, more than 90% of which occurred in the past two centuries. The electronic supplement to this article lists these data using European Macroseismic Scale (EMS-98) intensities with their geographic coordinates. We summarize these data graphically in the form of a spatially averaged intensity map for the subcontinent, a map that emphasizes the features of many previously published earthquake hazard maps for the Indian plate, but which more …


Analysis Of Streamflow In The St. Croix River: A Hydrologic Model, Stephanie A. Kleinschmidt Apr 2010

Analysis Of Streamflow In The St. Croix River: A Hydrologic Model, Stephanie A. Kleinschmidt

Geography Honors Projects

This project assesses how streamflow is affected by anthropogenic changes to the environment, looking specifically at the St. Croix River Basin. In 2004 the United States Geologic Survey (USGS) published a report on streamflow in the St. Croix River at two gaging stations: Danbury and St. Croix Falls. The streamflow at the upstream station near Danbury, Wisconsin remained stable over time, while an increase was observed at the station in St. Croix Falls, Wisconsin further downstream. In order to evaluate this disparity, this project utilizes a GIS hydrologic model to analyze the factors expected to be influencing the flow rate. …


Changing Depositional Environments In An Upper Ordovician Stratigraphic Sequence, Ashlock Formation, Madison County, Kentucky, Kevin G. Greff, Walter S. Borowski Apr 2010

Changing Depositional Environments In An Upper Ordovician Stratigraphic Sequence, Ashlock Formation, Madison County, Kentucky, Kevin G. Greff, Walter S. Borowski

EKU Faculty and Staff Scholarship

We investigate the sedimentology, stratigraphy, and depositional environments of a 7-meter, Upper Ordovician limestone sequence cropping out in Richmond, Madison County, Kentucky. The stratigraphic section lies within the Ashlock Formation with good lateral exposure stretching along 200 meters of a highway roadcut. We took approximately 20 samples from the measured section, focusing on representative samples and lithologic transitions. We use standard laboratory procedures in slabbing rock samples and making thin sections.

The Ashlock Formation here consists of alternating layers of limey mudstone and limestone (field units A through F). Megafossils - brachiopods, bryozoans, trilobites, gastropods, ostracodes, coralline algae, and bivalves …


Relatin Dissolved Oxygen Concentration To Fish Distribution In Jarecki Lake, Adam Sutton Apr 2010

Relatin Dissolved Oxygen Concentration To Fish Distribution In Jarecki Lake, Adam Sutton

Department of Environmental Studies: Undergraduate Student Theses

Abstract Water temperature and dissolved oxygen (DO) profiles were measured once every month from mid July to mid February in a relatively deep sand-pit lake in southeast Nebraska. These profiles showed depleted DO concentrations below the thermocline during summer stratification indicating areas fish will likely avoid in summer months. Colder temperatures in fall caused complete mixing of the water column allowing fish to inhabit all depths of the lake. An inverse temperature stratification occurred directly below the ice during winter months as ice cover cooled the surface water to below 4 degrees Celsius. Ice cover also blocked air – water …


Normal And Reverse Faulting Driven By The Subduction Zone Earthquake Cycle In The Northern Chilean Forearc, John P. Loveless, Richard W. Allmendinger, Matthew E. Pritchard, Gabriel González Mar 2010

Normal And Reverse Faulting Driven By The Subduction Zone Earthquake Cycle In The Northern Chilean Forearc, John P. Loveless, Richard W. Allmendinger, Matthew E. Pritchard, Gabriel González

Geosciences: Faculty Publications

Despite its location in a convergent tectonic setting, the Coastal Cordillera of northern Chile between 21°S and 25°S is dominated by structures demonstrating extension in the direction of plate convergence. In some locations, however, normal faults have been reactivated as reverse faults, complicating the interpretation of long-term strain. In order to place these new observations in a tectonic context, we model stress changes induced on these faults by the subduction earthquake cycle. Our simulations predict that interseismic locking on the plate boundary encourages normal slip on fore-arc faults, which may result from elastic rebound due to interplate earthquakes or from …


Contribution Of Soil Moisture Feedback To Hydroclimatic Variability, Nir Krakauer, B. I. Cook, M. J. Puma Mar 2010

Contribution Of Soil Moisture Feedback To Hydroclimatic Variability, Nir Krakauer, B. I. Cook, M. J. Puma

Publications and Research

While a variety of model experiments and analyses of observations have explored the impact of soil moisture variation on climate, it is not yet clear how large or detectable soil moisture feedback is across spatial and temporal scales. Here, we study the impact of dynamic versus climatological soil moisture in the GISS GCM ModelE (with prescribed sea-surface temperatures) on the variance and on the spatial and temporal correlation scale of hydrologically relevant climate variables (evaporation, precipitation, temperature, cloud cover) over the land surface. We also confirm that synoptic variations in soil moisture have a substantial impact on the mean climate …


Assessing The Potential To Detect Oil Spills In And Under Snow Using Airborne Ground-Penetrating Radar, John H. Bradford, David F. Dickens, Per Johan Brandvik Mar 2010

Assessing The Potential To Detect Oil Spills In And Under Snow Using Airborne Ground-Penetrating Radar, John H. Bradford, David F. Dickens, Per Johan Brandvik

CGISS Publications and Presentations

With recent increased interest in oil and gas exploration and development in the Arctic comes increased potential for an accidental hydrocarbon release into the cryosphere, including within and at the base of snow. There is a critical need to develop effective and reliable methods for detecting such spills. Numerical modeling shows that ground-penetrating radar (GPR) is sensitive to the presence of oil in the snow pack over a broad range of snow densities and oil types. Oil spills from the surface drain through the snow by the mechanisms of unsaturated flow and form geometrically complex distributions that are controlled by …


Testing Models Related To The Laramide Uplift Of The Uinta Mountains And Geologic Mapping Of The Jessen Butte 7.5 Minute Quadrangle, Dagget County, Utah And Sweetwater County, Wyoming, Coreen Hurst Mar 2010

Testing Models Related To The Laramide Uplift Of The Uinta Mountains And Geologic Mapping Of The Jessen Butte 7.5 Minute Quadrangle, Dagget County, Utah And Sweetwater County, Wyoming, Coreen Hurst

Theses and Dissertations

Geologic mapping of the Jessen Butte 7.5 minute quadrangle and the gathering of structural data throughout the quadrangle was used to determine the paleostress regime during the Laramide Orogeny along the north flank of the Uinta Mountains. The Henrys Fork thrust fault and the Uinta thrust fault are major north bounding faults and within the Jessen Butte quadrangle these faults transfer deformation from one to the other. The Jessen Butte thrust fault is a fault splay that splits off from the Henrys Fork thrust fault. Complex fold geometries were created by the interaction of the faults. Bedding plane orientation, mode …


Integrating Facies Analysis, Terrestrial Sequence Stratigraphy, And The First Detrital Zircon (U-Pb) Ages Of The Twist Gulch Formation, Utah, Usa: Constraining Paleogeography And Chronostratigraphy, Tyson L. Perkes Mar 2010

Integrating Facies Analysis, Terrestrial Sequence Stratigraphy, And The First Detrital Zircon (U-Pb) Ages Of The Twist Gulch Formation, Utah, Usa: Constraining Paleogeography And Chronostratigraphy, Tyson L. Perkes

Theses and Dissertations

The Jurassic Twist Gulch Formation of central Utah was deposited in the active Arapien sub-basin of the Western Cordillera foreland trough. We herein demonstrate the utility of integrating facies analysis, terrestrial sequence stratigraphy, and detrital zircon (U-Pb) ages to improve paleogeographic reconstructions as well as identify regional unconformities, locate fluvial depocenters, and infer sediment supply/accommodation space ratios. Strata of the Twist Gulch Formation in Pigeon Creek Canyon (PCC) near Levan, Utah consists primarily of alluvial deposits, while in Salina Canyon (SC) the Twist Gulch Formation is comprised of a mix of alluvial and marginal marine deposits associated with the Jurassic …


Slab Window Migration And Terrane Accretion Preserved By Low‐Temperature Thermochronology Of A Magmatic Arc, Northern Antarctic Peninsula, William R. Guenthner, David L. Barbeau Jr, Peter W. Reiners, Stuart N. Thomson Mar 2010

Slab Window Migration And Terrane Accretion Preserved By Low‐Temperature Thermochronology Of A Magmatic Arc, Northern Antarctic Peninsula, William R. Guenthner, David L. Barbeau Jr, Peter W. Reiners, Stuart N. Thomson

Faculty Publications

Existing paleogeographic reconstructions indicate that the northern Antarctic Peninsula was central to several Mesozoic and Cenozoic tectonic events that have implications for ocean circulation and continental margin evolution. To evaluate the exhumational record of these processes, we collected new samples and measured fission track and (U‐Th)/He cooling ages of apatite and zircon from 13 Jurassic and Cretaceous granitoids in western Graham Land between the northern tip of the peninsula and the Antarctic Circle. Apatite He data reveal distinct ages and systematic age patterns north and south of Anvers Island, near the midpoint of the study area: To the south, apatite …


Adverse Outcome Pathways And Ecological Risk Assessment: Bridging To Population-Level Effects, Vincent J. Kramer, Matthew A. Etterson, Markus Hecker, Cheryl A. Murphy, Guritno Roesijadi, Daniel J. Spade, Julann A. Spromberg, Magnus Wang, Gerald T. Ankley Mar 2010

Adverse Outcome Pathways And Ecological Risk Assessment: Bridging To Population-Level Effects, Vincent J. Kramer, Matthew A. Etterson, Markus Hecker, Cheryl A. Murphy, Guritno Roesijadi, Daniel J. Spade, Julann A. Spromberg, Magnus Wang, Gerald T. Ankley

United States Environmental Protection Agency: Publications

Maintaining the viability of populations of plants and animals is a key focus for environmental regulation. Population-level responses integrate the cumulative effects of chemical stressors on individuals as those individuals interact with and are affected by their conspecifics, competitors, predators, prey, habitat, and other biotic and abiotic factors. Models of population-level effects of contaminants can integrate information from lower levels of biological organization and feed that information into higher-level community and ecosystem models. As individual-level endpoints are used to predict population responses, this requires that biological responses at lower levels of organization be translated into a form that is usable …


Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry Mar 2010

Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry

Earth and Soil Sciences

Detrital zircon studies of miogeoclinal sediments can help provide a deeper look into the mechanisms leading to continental breakup by studying the evolution of the continental margin of North America. Few detrital zircon studies have been conducted to support previous research and theories about the sedimentation of the Miogeocline from the Neoproterozoic to the Cambrian. Studies targeted at the Basin and Range province of the western United States show a trend of increasing local sediment sources. We analyzed detrital zircons from the Pilot and Deep Creek Ranges in Nevada and Utah via LA-MC-ICP-MS at the University of Arizona LaserChron Center …


An Examination Of The Impact Of Air From China On Summertime Air Quality In Japan Before, During, And After The Beijing Olympics, Gary A. Morris, Hajime Akimoto, Masayuki Takigawa, Jun Hirokawa, Fumio Hasebe, Masatomo Fujiwara, Koji Miyagawa, Nicholay Krotkov, Jacquie Witte, Yugo Kanaya, Nathan Kellams, Ted Pietrzak Mar 2010

An Examination Of The Impact Of Air From China On Summertime Air Quality In Japan Before, During, And After The Beijing Olympics, Gary A. Morris, Hajime Akimoto, Masayuki Takigawa, Jun Hirokawa, Fumio Hasebe, Masatomo Fujiwara, Koji Miyagawa, Nicholay Krotkov, Jacquie Witte, Yugo Kanaya, Nathan Kellams, Ted Pietrzak

Physics and Astronomy Faculty Presentations

During July – September 2008 pollution controls in China associated with the Beijing Olympics led to emissions reductions of up to 43%, as observed by NASA satellite instruments. Pollution from China has an impact on air quality throughout East Asia. In this poster, we examine the impact of China's pollution on Japan through the use of Aura satellite data (2005 – 2009), ozonesonde data (2000 – 2009), and data from air quality surface monitors (2000 – 2009). We also examine the year-to-year variability in meteorological flow regimes through trajectory model simulations of transport to Japan from the areas around Beijing …


New Integrated Data Analyses Software Components, Ronald Conze, Frank Krysiak, Josh Reed, Yu-Chung Chen, Hans-Joachim Wallrabe-Adams, Colin Graham, New Jersey Shallow Shelf Science Team, Volker Wennrich, Lake El’Gygytgyn Science Team Mar 2010

New Integrated Data Analyses Software Components, Ronald Conze, Frank Krysiak, Josh Reed, Yu-Chung Chen, Hans-Joachim Wallrabe-Adams, Colin Graham, New Jersey Shallow Shelf Science Team, Volker Wennrich, Lake El’Gygytgyn Science Team

ANDRILL Research and Publications

Data management in scientific drilling programs such as the Integrated Ocean Drilling Program (IODP), the International Continental Scientific Drilling Program (ICDP), and the Antarctic Drilling Program (ANDRILL) performs two functions: firstly, the capture of drilling and scientific data during an expedition, and secondly, the long-term storage and dissemination of these data. Here we describe the progress in linking data management with stand-alone data capture and visualization applications. This provides a two-way flow of data between the database and the applications, and a more integrated data environment for scientists. The new system has been tested, so far, with cores from the …


Wayne E. Sabbe Arkansas Soil Fertility Studies 2009, Nathan A. Slaton Mar 2010

Wayne E. Sabbe Arkansas Soil Fertility Studies 2009, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts also be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts.


Geodetic Imaging Of Plate Motions, Slip Rates, And Partitioning Of Deformation In Japan, John P. Loveless, Brendan J. Meade Feb 2010

Geodetic Imaging Of Plate Motions, Slip Rates, And Partitioning Of Deformation In Japan, John P. Loveless, Brendan J. Meade

Geosciences: Faculty Publications

Interseismic deformation in Japan results from the combined effects of tectonic processes including rotation of crustal blocks and the earthquake cycle process of elastic strain accumulation about upper plate faults and subduction zone interfaces. We use spherical linear block theory constrained by geodetic observations from densely spaced Global Positioning System (GPS) stations to estimate plate motions, fault slip rates, and spatially variable interplate coupling on the Japan-Kuril, Sagami, and Nankai subduction zones. The reference model developed in this paper consists of 20 blocks, produces a mean residual velocity magnitude of 1.84 mm/yr at 950 stations, and accounts for 96% of …


Photo Highlights Of The 30th Kentucky Alfalfa Conference, Kentucky Alfalfa Conference Feb 2010

Photo Highlights Of The 30th Kentucky Alfalfa Conference, Kentucky Alfalfa Conference

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


How We Produce & Market Alfalfa Hay, Clayton Geralds Feb 2010

How We Produce & Market Alfalfa Hay, Clayton Geralds

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Growing Alfalfa For Wildlife, Don Ball Feb 2010

Growing Alfalfa For Wildlife, Don Ball

Kentucky Alfalfa and Stored Forage Conference

Alfalfa has long been recognized as a superb forage crop, which is why it is widely grown for dairy cattle, horses, sheep, and many other types of domesticated forage-consuming animals. Reasons for its popularity include wide adaptation, excellent nutritive value, good yield potential, perennial growth habit, a long growing season, and the fact that (in association with Rhizobium bacteria) it is a nitrogen-fixing legume that does not require periodic applications of nitrogen fertilizer.


Alfalfa Varieties For The Future, Joe Bouton Feb 2010

Alfalfa Varieties For The Future, Joe Bouton

Kentucky Alfalfa and Stored Forage Conference

When breeding tomorrow’s alfalfa varieties, most groups employ a model of combining traditional plant breeding with biotechnology tools in order to incorporate useful traits. In this model, the conventional variety development process will be the method of choice for most traits where breeders have traditionally made progress such as adaptation, heading date, disease and insect resistance, general persistence conditions such as grazing and traffic tolerance, and even yield. It has been very successful in adding economic value to the forage and livestock operations of many producers (Bouton 2007). These traditionally developed varieties will also be used as the germplasm platform …


Do's And Don'ts In Grazing Alfalfa, Ken Johnson Feb 2010

Do's And Don'ts In Grazing Alfalfa, Ken Johnson

Kentucky Alfalfa and Stored Forage Conference

I want to discuss some of the issues in a talk I presented nearly twenty years ago. At that point we had been grazing Alfalfa about eight years and made some general remarks about the concerns I had at the time. I will look at these as presented then and how the thoughts may have changed.


Is There A Benefit To Alfalfa Balage?, Gary Bates Feb 2010

Is There A Benefit To Alfalfa Balage?, Gary Bates

Kentucky Alfalfa and Stored Forage Conference

Making hay in the mid-South has always been a difficult process. High humidity and rainfall often make drying a long, tedious, if not impossible proposition. Over the last few years there has been an increased interest in making round bale silage, or balage, from forage crops. Fermenting alfalfa for storage has several advantages and disadvantages over regular haymaking systems.


Alfalfa Hay For Horses, Robert Coleman Feb 2010

Alfalfa Hay For Horses, Robert Coleman

Kentucky Alfalfa and Stored Forage Conference

When horse owners consider hay for their animals, a number of criteria are generally considered. Of major importance is the hay must be free of mold and dust. It needs to contain nutrients needed by the horse and it must be palatable. If these criteria are met, the type of hay should not matter. However, that is not the case with many horse owners. When discussing the selection of hay, many owners first consider the type of hay. Can it be alfalfa or should it be a grass or how about a mix of grass and a legume. If a …


Value Of Alfalfa In Rotation, S. Ray Smith Feb 2010

Value Of Alfalfa In Rotation, S. Ray Smith

Kentucky Alfalfa and Stored Forage Conference

There are about 23 million acres of alfalfa in the US. Alfalfa plus other hay is the most valuable crop in the US, behind only corn and soybeans. In Kentucky alfalfa is planted on over 300,000 acres and is an economically important crop for beef and dairy farmers, cash hay producers, and provides tremendous benefits for subsequent crops. There are also many non-agricultural benefits to alfalfa.


Advances In Alfalfa Seed Coatings, Bill Talley Feb 2010

Advances In Alfalfa Seed Coatings, Bill Talley

Kentucky Alfalfa and Stored Forage Conference

The volume of alfalfa being sold as coated seed has been in the growth mode for several years. This growth is being fueled by greater acceptance from the producer, as well as the many value added components that are now labeled and being offered as seed treatments. Originally seed coatings were looked at as a better way to deliver rhizobia to insure plant nodulation. This is still one goal, but many more value added components are now labeled that offer better plant protection, increased water absorption, enhanced germination, and micro-nutrient availability, as well as insect and parasite control. Another area …


Kentucky Alfalfa Conference Reflections After 30 Years, Garry D. Lacefield Feb 2010

Kentucky Alfalfa Conference Reflections After 30 Years, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

This event today marks the 30th consecutive year we have come together for a full day’s conference featuring "Alfalfa - Queen of the Forages" as the theme and focal point. Only one other state (California) in the U.S. has such an annual event.