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Evaluation Of The Sensitivity Of Inventory And Monitoring National Parks To Acidification Effects From Atmospheric Sulfur And Nitrogen Deposition, Northern Great Plains Network (Ngpn), T. J. Sullivan, T. C. Mcdonnell, G. T. Mcpherson, S. D. Mackey, D. Moore Apr 2011

Evaluation Of The Sensitivity Of Inventory And Monitoring National Parks To Acidification Effects From Atmospheric Sulfur And Nitrogen Deposition, Northern Great Plains Network (Ngpn), T. J. Sullivan, T. C. Mcdonnell, G. T. Mcpherson, S. D. Mackey, D. Moore

United States National Park Service: Publications

Northern Great Plains Network (NGPN)

National maps of atmospheric sulfur (S) and nitrogen (N) emissions and deposition are provided in Maps A through D as context for subsequent network data presentations. Maps A and B show county level emissions of total S and total N for the year 2002. Maps C and D show total S and total N deposition, again for the year 2002.

There are three parks in the Northern Great Plains Network that are larger than 100 square miles: Badlands (BADL), Missouri (MNRR), and Theodore Roosevelt (THRO). In addition, there are 10 smaller parks.

Total annual S …


Middle To Late Miocene Extremely Rapid Exhumation And Thermal Reequilibration In The Kung Co Rift, Southern Tibet, Jeffrey Lee, Christian Hager, Simon R. Wallis, Daniel F. Stockli, Martin J. Whitehouse, Mutsuki Aoya, Yu Wang Mar 2011

Middle To Late Miocene Extremely Rapid Exhumation And Thermal Reequilibration In The Kung Co Rift, Southern Tibet, Jeffrey Lee, Christian Hager, Simon R. Wallis, Daniel F. Stockli, Martin J. Whitehouse, Mutsuki Aoya, Yu Wang

All Faculty Scholarship for the College of the Sciences

The Kung Co rift is an approximately NNW striking, WSW dipping normal fault exposed in southern Tibet and is part of an extensive network of active approximately NS striking normal faults exposed across the Tibetan Plateau. Detailed new and published (U-Th)/He zircon and apatite thermochronometric data from the footwall of the early Miocene Kung Co granite provide constraints on the middle Miocene to present-day exhumation history of the footwall to the Kung Co fault. Inverse modeling of thermochronometric data yield age patterns that are interpreted as indicating (1) initiation of normal fault slip at ∼12–13 Ma and rapid exhumation of …


Evaluation Of The Sensitivity Of Inventory And Monitoring National Parks To Nutrient Enrichment Effects From Atmospheric Nitrogen Deposition Northern Great Plains Network (Ngpn), T. J. Sullivan, T. C. Mcdonnell, G. T. Mcpherson, S. D. Mackey, D. Moore Feb 2011

Evaluation Of The Sensitivity Of Inventory And Monitoring National Parks To Nutrient Enrichment Effects From Atmospheric Nitrogen Deposition Northern Great Plains Network (Ngpn), T. J. Sullivan, T. C. Mcdonnell, G. T. Mcpherson, S. D. Mackey, D. Moore

United States National Park Service: Publications

Northern Great Plains Network (NGPN)

National maps of atmospheric N emissions and deposition are provided in Maps A and B as context for subsequent network data presentations. Map A shows county level emissions of total N for the year 2002. Map B shows total N deposition, again for the year 2002.

There are three parks in the Northern Great Plains Network that are larger than 100 square miles: Badlands (BADL), Missouri (MNRR), and Theodore Roosevelt (THRO). In addition, there are 10 other smaller parks.

Total annual N emissions, by county, are shown in Map C for lands in and surrounding …


Decolorization Of Azo Dye (Orange Mr) By An Autochthonous Bacterium, Micrococcus Sp. Dbs 2, Rajee Olaganathan, Jamila Patterson Jan 2011

Decolorization Of Azo Dye (Orange Mr) By An Autochthonous Bacterium, Micrococcus Sp. Dbs 2, Rajee Olaganathan, Jamila Patterson

Publications

Soil and sediment samples obtained from Orange MR dye contaminated habitat were screened for heterotrophic bacterial population. The heterotrophic bacterial density of dye-contaminated soil was 2.14 9 106 CFU/g. The generic composition of heterotrophic bacterial population was primarily composed of 10% of Proteus sp., 15% Aeromonas sp., 20% Bacillus sp., 25% Pseudomonas sp. and 30% Micrococcus sp. The bacterial strain that decolorized the azo dye Orange MR up to 900 ppm was identified as Micrococcus sp. The optimum inoculum load, pH and temperature were found to be 5%, 6 and 35°C, respectively. The rate of decolorization was assessed using spectrophotometer …


Subaerial Freshwater Stromatolites In Deer Cave, Sarawak – A Unique Geobiological Cave Formation, Joyce Lundberg, Donald A. Mcfarlane Jan 2011

Subaerial Freshwater Stromatolites In Deer Cave, Sarawak – A Unique Geobiological Cave Formation, Joyce Lundberg, Donald A. Mcfarlane

WM Keck Science Faculty Papers

A suite of distinctive freshwater subaerial phosphatic stromatolites is developed close to the northeastern entrance of Deer Cave, Gunung Mulu National Park, Sarawak, Borneo, in conditions of very low light but ample supply of nutrients from guano. These stromatolites are not particulate; they are composed of alternating layers of more porous and more dense amorphous hydroxylapatite. This biomineralization occurs as moulds of coccoid (the majority) and filamentous (less abundant) cyanobacteria. Mineralization occurs at a pH of ~ 7.0 in the extracellular sheaths and in micro-domains of varying carbonate content in the surrounding mucus of the biofilm. The most recent surfaces …


A Trans-Dimensional Bayesian Markov Chain Monte Carlo Algorithm For Model Assessment Using Frequency-Domain Electromagnetic Data, Burke J. Minsley Jan 2011

A Trans-Dimensional Bayesian Markov Chain Monte Carlo Algorithm For Model Assessment Using Frequency-Domain Electromagnetic Data, Burke J. Minsley

United States Geological Survey: Staff Publications

A meaningful interpretation of geophysical measurements requires an assessment of the space of models that are consistent with the data, rather than just a single, ‘best’ model which does not convey information about parameter uncertainty. For this purpose, a trans-dimensional Bayesian Markov chain Monte Carlo (MCMC) algorithm is developed for assessing frequency domain electromagnetic (FDEM) data acquired from airborne or ground-based systems. By sampling the distribution of models that are consistent with measured data and any prior knowledge, valuable inferences can be made about parameter values such as the likely depth to an interface, the distribution of possible resistivity values …


Variations In Concentrations And Compositions Of Polycyclic Aromatic Hydrocarbons (Pahs) In Coals Related To The Coal Rank And Origin, Susanne Laumann, Vesna Micic Batka, Michael A. Kruge, Christine Achten, Reinhard Sachsenhofer, Jan Schwarzbauer, Thilo Hofmann Jan 2011

Variations In Concentrations And Compositions Of Polycyclic Aromatic Hydrocarbons (Pahs) In Coals Related To The Coal Rank And Origin, Susanne Laumann, Vesna Micic Batka, Michael A. Kruge, Christine Achten, Reinhard Sachsenhofer, Jan Schwarzbauer, Thilo Hofmann

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The release of unburnt coal particles and associated polycyclic aromatic hydrocarbons (PAHs) may cause adverse impacts on the environment. This study assessed variations in the concentration and composition of PAHs in a set of fifty coal samples from eleven coal basins worldwide. The maximum PAH concentrations at high volatile bituminous rank were recorded in samples from a single basin. Considering the entire sample, the highest PAH concentrations were in fact found outside of this rank range, suggesting that the maceral composition and thus the coal's origin also influenced PAH concentrations. The examination of the PAH compositions revealed that alkylated 2-3 …


Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya Jan 2011

Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya

Department of Earth, Environment and Sustainability Faculty Publications

The objective of this encyclopedia is to present the current state of scientific understanding of various aspects of earth’s cryosphere – snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost – and their related interdisciplinary connections under one umbrella. Therefore, every effort has been made to provide a comprehensive coverage of cryosphere by including a broad array of topics, such as the atmospheric processes responsible for snow formation; snowfall observations; snow cover and snow surveys; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide …


Arctic Sea-Ice Melt In 2008 And The Role Of Solar Heating, Donald K. Perovich, Jacqueline A. Richter-Menge, Kathleen F. Jones, Bonnie Light Jan 2011

Arctic Sea-Ice Melt In 2008 And The Role Of Solar Heating, Donald K. Perovich, Jacqueline A. Richter-Menge, Kathleen F. Jones, Bonnie Light

Dartmouth Scholarship

There has been a marked decline in the summer extent of Arctic sea ice over the past few decades. Data from autonomous ice mass-balance buoys can enhance our understanding of this decline. These buoys monitor changes in snow deposition and ablation, ice growth, and ice surface and bottom melt. Results from the summer of 2008 showed considerable large-scale spatial variability in the amount of surface and bottom melt. Small amounts of melting were observed north of Greenland, while melting in the southern Beaufort Sea was quite large. Comparison of net solar heat input to the ice and heat required for …


An Investigation Of The Seismic Hazards Of The El Paso-Juarez Region: The Nature And Extent Of The Southern East Franklin Mountains Fault Zone, Victor Manuel Avila Jan 2011

An Investigation Of The Seismic Hazards Of The El Paso-Juarez Region: The Nature And Extent Of The Southern East Franklin Mountains Fault Zone, Victor Manuel Avila

Open Access Theses & Dissertations

ABSTRACT

The El Paso-Ciudad Juarez Region is situated at the southern end of the active Rio Grande Rift within the Mesilla and Hueco basins. The Hueco basin is separated from the eastern Franklin Mountains by a prominent fault, the Eastern Boundary Fault. Studies of this fault have revealed fault scarps that displace Quaternary deposits (Keaton et al., 1995; Raney and Collins, 1990; Lovejoy, 1976). This fault is cataloged as an active fault in the National Seismic Hazard Map with an estimated slip rate of 0.1 mm/yr. A fault with similar characteristics as the Eastern Boundary Fault extends further to the …


Collaboration And Climate Action At The Local Scale, Linda Lyshall Jan 2011

Collaboration And Climate Action At The Local Scale, Linda Lyshall

Antioch University Dissertations & Theses

This dissertation encompasses a case study and a Participatory Action Research project. The case study focuses on climate change mitigation activities within King County, Washington and its 39 cities and towns and discusses progress and challenges related to transportation issues, efficiency measures, and sustainability planning. The findings indicate there is a high level of activity in waste reduction, environmental outreach and education, bicycle and pedestrian promotion, tree canopy protection, sustainability policies, and green building. Other categories, such as energy efficiency, electric vehicle infrastructure, and greenhouse gas emission inventories and goal setting are on the rise. Twelve of the cities were …


Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton Jan 2011

Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton

University of Kentucky Master's Theses

Currently, bacterial movement in karst aquifers is not well understood. Use of stable isotopes to label non-pathogenic Escherichia coli as a particulate groundwater tracer in karst systems has been examined in previous studies. Loss of the stable isotope signal is anticipated in traces greater than 500 m in length. Potential loss of 15N due to predation by protozoa was examined. Filter-sterilized water from Royal Spring in Georgetown, Kentucky, was inoculated with a mixture of either Tetrahymena pyriformis or Colpoda steinii and 15N-enriched E. coli and stored in the dark at 14°C. Samples were analyzed for their nitrogen isotope …


Policy And Science Of Geothermal Heat Use At Mcmurdo Station, Antarctica, Joe Alvine Dec 2010

Policy And Science Of Geothermal Heat Use At Mcmurdo Station, Antarctica, Joe Alvine

Department of Environmental Studies: Undergraduate Student Theses

My thesis research project deals with the use of geothermal heat in Antarctica. Currently it is not allowed due to article 7 of the 1991 Protocol on Environmental Protection that placed a 50 moratorium on the exploitation of mineral resources. The US main base in Antarctica, McMurdo Station is currently powered by diesel generators that are inefficient, cause environmental damage, and is expensive to run. By exploring alternative energy options, McMurdo Station can reduce its dependence on non-renewable energy sources. By determining the geothermal potential of McMurdo Station, this project explores the possibilities and benefits that would occur with the …


The Influence Of Sediment Bays On Reducing Incoming Sediment In Holmes Lake, Lincoln, Nebraska, Alex Fischer Dec 2010

The Influence Of Sediment Bays On Reducing Incoming Sediment In Holmes Lake, Lincoln, Nebraska, Alex Fischer

Department of Environmental Studies: Undergraduate Student Theses

Lakes in the urban environment are often challenged with issues of water quality. Holmes Lake, located in Lincoln, Nebraska, has experienced such problems. In an effort to improve water quality in Holmes Lake, the city installed several control devices. One of the devices installed were sediment bays. This study evaluated the effectiveness of those sediment bays by measuring turbidity and suspended sediment after rain events at different locations in and out of the bays. The study found that the bays helped to reduce sediment in some cases, but in other cases no reduction was shown.


The Effect Of Enso On Nebraska Winter Snowfall, Jonathan Burnham Dec 2010

The Effect Of Enso On Nebraska Winter Snowfall, Jonathan Burnham

Department of Environmental Studies: Undergraduate Student Theses

No abstract provided.


Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2010

Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Hrc Enews — 2010 Fall, Megan K. Svarz Oct 2010

Hrc Enews — 2010 Fall, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, and a "new faces" listing for new staff, affiliates, and researchers.


Development Of Agroecology Based Garden System And Educational Program At Grand Valley State University, Kendall Gilbert, Edwin Joseph Oct 2010

Development Of Agroecology Based Garden System And Educational Program At Grand Valley State University, Kendall Gilbert, Edwin Joseph

Student Summer Scholars Manuscripts

This study was part of a twelve- week project to introduce agroecology growing principles and educational models at the Community Garden on the campus of Grand Valley State University in Allendale, Michigan. This project was set up to be a demonstration for the further development of the garden space as an area for agroecology focused education, extension, and outreach. To accomplish this, three areas of change became essential components to developing a garden space that can serve as a living laboratory, demonstration area, and outdoor classroom. The first project goal was to develop and create a demonstration garden plot that …


Petrology And Geochemistry Of The Pompton Pink Granite, New Jersey Highlands, Ian Phillip Johnson Aug 2010

Petrology And Geochemistry Of The Pompton Pink Granite, New Jersey Highlands, Ian Phillip Johnson

Theses, Dissertations and Culminating Projects

The Pompton Pink Granite is a small (~1 km2), post-orogenic granitoid body located in the New Jersey Highlands. It is a mildly peraluminous (ASI or aluminum saturation index, A/CNK = molar Al2O₃ / (CaO + Na₂O + K₂O) > 1.0) pluton composed of microcline, microperthite, quartz, oligoclase, epidote, biotite, and magnetite and is classified as a granite based on its mineral and geochemical composition using standard IUGS classification schemes. The Pompton Pink Granite shows similar major-element geochemistry to other A-type granitoids found in the New Jersey Highlands, but its trace­ element geochemistry distinguishes it from these other …


Simulation Of Contaminant Transport From Solid Domestic Waste Disposal Sites In The Warri Deltaic Plain Sands, Warri-Effurun, Nigeria, Charles Onoriode Usiaphre Aug 2010

Simulation Of Contaminant Transport From Solid Domestic Waste Disposal Sites In The Warri Deltaic Plain Sands, Warri-Effurun, Nigeria, Charles Onoriode Usiaphre

Theses, Dissertations and Culminating Projects

Protecting the groundwater resource in the Warri Deltaic Plain sand from the impact of anthropogenic contamination requires an understanding and knowledge of groundwater flow paths, transport processes and the source of contamination. This study was carried out to find out contaminant transport from solid domestic waste sites to the groundwater. The U.S. Geological Survey three-dimensional finite-difference code, MODFLOW, was used to simulate the groundwater flow. The flow pattern reveals predominantly downward flow, with major horizontal motion towards towns around Ekurede Urhobo and Ekurede Itsekiri in Warri. Simulation of advective contaminant transport using MODPATE1 for particle tracking indicates local movement of …


Rock Magnetic And Remanence Properties Of Both Synthetic Martian Basaltic Intrusions And Dropstones Along The East Antarctic Margin, To Aid In The Understanding Of The Carriers Of Crustal Magnetic Anomalies, David Michael Cuomo Jr. Jul 2010

Rock Magnetic And Remanence Properties Of Both Synthetic Martian Basaltic Intrusions And Dropstones Along The East Antarctic Margin, To Aid In The Understanding Of The Carriers Of Crustal Magnetic Anomalies, David Michael Cuomo Jr.

Theses, Dissertations and Culminating Projects

This thesis examines potential carriers of magnetic anomalies found in remote areas where direct sampling is impossible. The areas examined are the southern hemisphere of Mars and the East Antarctic Margin. We examine the rock magnetic and remanence properties of synthetic Mars basalts and Antarctic dropstones, to predict the type and intensity of anomaly they would produce.

The anomalies measured within the Martian crust are entirely remanent magnetization and are remarkably orders of magnitude stronger than the strongest terrestrial anomaly. Two basalt compositions denoted M-type and T-type, deemed relevant to the crust of Mars, were synthesized to examine contrasts in …


Sediment Flux Through The Rio Grande River: A Monsoonal Effect, Troy C. Hiatt Jun 2010

Sediment Flux Through The Rio Grande River: A Monsoonal Effect, Troy C. Hiatt

Theses and Dissertations

Climate has historically been recognized as an influence on sediment flux and deposition. The North American Monsoon is suggested as the forcing mechanism of deltaic progradational events of the Rio Grande River delta. Interpretations of reflection seismic profiles reveal that eustatic rise in sea-level from the Last Glacial Maximum to present is accompanied by several regressional events of the Rio Grande delta 5.5, 9.5, and 11.5 ka BP. Much of the migration of depositional facies within a delta system is forced by hinterland tectonics and base-level rise and fall. However, we suggest that the movement of facies within the Rio …


Characterization Of Contaminant And Biomass-Derived Organic Matter In Sediments From The Lower Passaic River, New Jersey, Usa, Nicole Michelle Bujalski May 2010

Characterization Of Contaminant And Biomass-Derived Organic Matter In Sediments From The Lower Passaic River, New Jersey, Usa, Nicole Michelle Bujalski

Theses, Dissertations and Culminating Projects

The lower Passaic River has been heavily contaminated during the twentieth century due to the industrial activity within its watershed. The geochemistry of four deep cores was explored using an environmental forensics approach. Pyrolysis gaschromatography/ mass spectrometry (Py-GC/MS) and grain size analysis was performed in conjunction with radiometric analysis to understand the sediment and contaminant transport patterns. The distinctive molecular finger prints were identified by employing chromatogram fingerprints, polycyclic aromatic hydrocarbon distribution, principal component analysis, and chemostratigraphy. Radiometric analysis and observations of chlorinated contaminant patterns allowed for average sample depths to be correlated to approximate ages. Additionally three distinct zones …


Ice Sheet Dynamics Of The Past 17 Myr In Southern Mcmurdo Sound, Antarctica: A Heavy Mineral Analysis, Daniel William Hauptvogel May 2010

Ice Sheet Dynamics Of The Past 17 Myr In Southern Mcmurdo Sound, Antarctica: A Heavy Mineral Analysis, Daniel William Hauptvogel

Theses, Dissertations and Culminating Projects

The ANtarctic Geologie DRILLing program (ANDRILL) drilled a sediment core from a sea ice platform in the Ross Sea in southern McMurdo Sound (SMS), Antarctica, in late 2007. The core site is located just to the east of the Transantarctic Mountains (TAM) along the western margin of a half graben and is a site of heavy sedimentation from the TAM, the East Antarctic Ice Sheet (EAIS), the McMurdo Volcanic Group (MVG), and the West Antarctic Ice Sheet (WAIS) and Ross Ice Shelf. The upper 650 m of the core were analyzed for heavy minerals in order to interpret ice sheet …


Talus Slope Processes In The Appalachian : An Analysis Of Rock Size And Shape On The Shawangunk Ridge, Northwestern New Jersey, Muhammad Hamidul Haque May 2010

Talus Slope Processes In The Appalachian : An Analysis Of Rock Size And Shape On The Shawangunk Ridge, Northwestern New Jersey, Muhammad Hamidul Haque

Theses, Dissertations and Culminating Projects

Sphericity, hardness, roundness, and size of talus boulders were analyzed to understand the mass wasting process on the Shawangunk Ridge in northwestern New Jersey. Similar studies have been conducted in other localities (e.g., Lassen Peak, California and Spitsbergen, Sweden) but few works were carried out in the eastern United States, particularly in the Appalachian region. During the Pleistocene, ice sheets advanced in North America, and glacial and periglacial (soil and rock affected by ice) environments existed throughout the Appalachians. Although the periglacial climate is not present in this region right now, rock falls are still active where weak joints are …


Minimum Riparian Buffer Width For Maintaining Water Quality And Habitat Along Stevens Creek, Sammi Bray Apr 2010

Minimum Riparian Buffer Width For Maintaining Water Quality And Habitat Along Stevens Creek, Sammi Bray

Department of Environmental Studies: Undergraduate Student Theses

ABSTRACT Riparian buffer zones are important sites of biodiversity, sediment trapping, pollutant removal, and hydrologic regulation that have significant implications for both people and wildlife. Urbanization’s influence on and need for adequate water quality increases the need for careful planning in regards to riparian areas. Wildlife are key components in the ecosystem functions of riparian zones and require consideration in peri-urban planning as well. This study reviews relevant literature to determine the recommended minimum riparian buffer width for maintaining water quality and habitat along Stevens Creek in Lincoln, Nebraska. Only sources that listed a specific purpose related to water quality …


Yellowstone Super-Volcano: Evaluation, Potential Threats, And Possible Effects On Nebraska Citizens Health And Prosperity, Jennie Korgie Apr 2010

Yellowstone Super-Volcano: Evaluation, Potential Threats, And Possible Effects On Nebraska Citizens Health And Prosperity, Jennie Korgie

Department of Environmental Studies: Undergraduate Student Theses

Abstract Yellowstone National Park is located over a hot spot under the North American tectonic plate and holds a potentially explosive super-volcano that has the ability to cause deadly consequences on the North American continent. After an eruption the surrounding region would see the greatest devastation, covered by pyroclastic deposits and thick ash fall exterminating most all life and destroying all structures in its path. In landscapes of greater distance from the event the consequences will be less dramatic yet still substantial. Records of previous eruption data from the Yellowstone super-volcano show that the ash fall out from the eruption …


Cellulosic Ethanol: The Benefits, Obstacles, And Implications For Nebraska, Cassidee Lin Thompson Apr 2010

Cellulosic Ethanol: The Benefits, Obstacles, And Implications For Nebraska, Cassidee Lin Thompson

Department of Environmental Studies: Undergraduate Student Theses

Abstract Ethanol is a biofuel that has unique capabilities to mitigate global climate change by reducing greenhouse gas emissions while simultaneously supporting rural economies and decreasing the United States’ dependence on foreign oil. Currently, the state of Nebraska depends on corn ethanol, which may be unsustainable. Cellulosic ethanol is a promising alternative but it is not without its problems, including high production costs and potential environmental damage. This thesis is an attempt to understand the benefits, downfalls, and processes of corn-based and cellulosic ethanol and the potential implications to Nebraska. This research should shed some light on the current obstacles …


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 …


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 …