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The Imperative Of Conserving California's Foothill Oak Woodlands, Lauren Phillips Dec 2013

The Imperative Of Conserving California's Foothill Oak Woodlands, Lauren Phillips

Social Sciences

No abstract provided.


The Influence Of Hydrogeomorphology, Soil Redox Conditions, And Salinity On The Spatial Zoning Of Saltgrass, Salt Rush, And Cattails In Scotts Creek Marsh, Swanton Pacific Ranch, Ca, Mark D. Gormley Dec 2013

The Influence Of Hydrogeomorphology, Soil Redox Conditions, And Salinity On The Spatial Zoning Of Saltgrass, Salt Rush, And Cattails In Scotts Creek Marsh, Swanton Pacific Ranch, Ca, Mark D. Gormley

Master's Theses

Scotts Creek Marsh (SCM) is a small coastal wetland ecosystem in Davenport, CA. The vegetation of SCM is dominated by three halophytic zones comprised of saltgrass, salt rush, cattails. The objectives of the study were (i) to investigate the variables that influence the zoning of the three dominant halophyte communities in SCM and (ii) to the test the effectiveness of Indicator of Reduction in Soil (IRIS) tubes to indicate the reduction of S. The study examined the following parameters from April 6 to July 21, 2013: (i) the HGM of Scotts Creek Marsh, (ii) soil oxidation and reduction (redox) conditions, …


Methylmercury Fate In The Hypersaline Environment Of The Great Salt Lake: A Critical Review Of Current Knowledge, Danielle Barandiaran Dec 2013

Methylmercury Fate In The Hypersaline Environment Of The Great Salt Lake: A Critical Review Of Current Knowledge, Danielle Barandiaran

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Methylmercury (MeHg) is a highly potent neurotoxic form of the environmental pollutant Mercury (Hg). The processes that are responsible for the conversion of Hg to MeHg are known to be both biotic and abiotic in freshwater systems. Although MeHg contamination is well documented in Great Salt Lake (GSL), the conversion of Hg into MeHg is not well-understood in saline environments much less in hypersaline waters such as GSL. The GSL is a broad, shallow high altitude (1280 m above sea level) lake that is exposed to large amounts of ultraviolet radiation and evaporation, which lead to great volatilization losses of …


Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith Dec 2013

Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith

Graduate Theses and Dissertations

Sustainability in agriculture is paramount to assuring continued production from our most naturally fertile soils. Storing carbon (C) in soil as organic matter through sustainable agricultural management practices can both remove atmospheric C and improve soil quality. The objective of this study was to evaluate the long-term effects of water management (irrigation and dryland), residue management [burn and no-burn, conventional (CT) and no-tillage (NT)] and residue/fertility level (high and low) on soil respiration and aggregate stability in a wheat- (Triticum aestivum L.) soybean [Glycine max (L.) Merr.], double-crop system in a silt-loam soil (Aquic Fraglossudalf) in the Mississippi River Delta …


La Yeguada Volcanic Vomplex In The Republic Of Panama: An Assessment Of The Geologic Hazards Using 40ar/39ar Geochronology, Karinne L. Knutsen, William I. Rose, Brian Jicha Nov 2013

La Yeguada Volcanic Vomplex In The Republic Of Panama: An Assessment Of The Geologic Hazards Using 40ar/39ar Geochronology, Karinne L. Knutsen, William I. Rose, Brian Jicha

Department of Geological and Mining Engineering and Sciences Publications

La Yeguada volcanic complex is one of three Quaternary volcanic centers in Panama. To assess potential geologic hazards, new samples were analyzed using argon analysis (40Ar/39Ar), and obtained the following: the most recent eruption occurred approximately 32,000 years ago at the Media Luna cinder cone; the youngest dated eruption from the main dome complex occurred 357 ± 19 ka, producing the Castillo dome unit; Cerro Picacho, a separate dacite dome 1.5 km east of the main complex is 4.47 ± 0.23 Ma; and the El Satro Pyroclastic Flow unit surrounds the northern portion of the volcanic …


Icaverns: Interpretation, There's An App For That!, Sandra Dianne Joop Nov 2013

Icaverns: Interpretation, There's An App For That!, Sandra Dianne Joop

National Cave and Karst Management Symposium 2013

A quarter of a century ago, cave and karst resources were declared irreplaceable with the passing of the Federal Cave Resources Protection Act. Yet, today, few understand the importance or fragility of these resources. Human interactions in karst areas make these resources highly susceptible to damage. Nonpersonal interpretation digital media products could serve as an important tool to bridge this informational gap.

Worldwide, there are hundreds of parks or parklike attractions focusing on cave, spring, or sinkhole resources. Their visitors have a built-in curiosity about these places. Engaging this audience in interpretive programming could greatly increase their speleological knowledge. Paradoxically, …


The Western Kentucky University Crumps Cave Research & Education Preserve, Chris Groves, Jason Polk, Ben Miller, Pat Kambesis, Carl Bolster, Sean Vanderhoff, Beth Tyrie Nov 2013

The Western Kentucky University Crumps Cave Research & Education Preserve, Chris Groves, Jason Polk, Ben Miller, Pat Kambesis, Carl Bolster, Sean Vanderhoff, Beth Tyrie

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Crumps Cave is located about one kilometer northeast of Smiths Grove, Kentucky (Figures 1, 2, and 3). The only known entrance was purchased by Western Kentucky University (WKU) in 2009 through a grant from the Kentucky Heritage Land Conservation Fund and the cave is managed as the focal point of a research and education preserve to study a wide range of environmental conditions and dynamics, and their interactions, using high-resolution electronic monitoring along with geochemical sampling, analysis and modeling. Crews from WKU’s Hoffman Environmental Research Institute visit the cave weekly for sampling, data downloading, and equipment maintenance, with a major …


Postglacial Faunal Records From Cave Deposits In Jasper National Park, Alberta, Canada, Christopher N. Jass, Greg Horne, Dave Critchley Nov 2013

Postglacial Faunal Records From Cave Deposits In Jasper National Park, Alberta, Canada, Christopher N. Jass, Greg Horne, Dave Critchley

National Cave and Karst Management Symposium 2013

In 2009, we initiated an on-going, long term research project that focuses on exploration of fossil-bearing cave deposits in Jasper National Park. Specifically, we were interested in understanding patterns of mammalian re-colonization of mountainous regions following late Pleistocene deglaciation. Our work has focused on the identification of fossil-bearing cave deposits, excavation and sampling of those deposits, and radiocarbon dating of recovered remains. Examined sites have at least an age of 9600 years BP. Research at four cave sites, located in relatively close proximity to one another, is contributing to an improved understanding of the late Quaternary record of Jasper National …


Caver Quest 3d Virtual Cave Simulation Of Snowy River In Fort Stanton Cave, Ronald J. Lipinski, Pete Lindsley Nov 2013

Caver Quest 3d Virtual Cave Simulation Of Snowy River In Fort Stanton Cave, Ronald J. Lipinski, Pete Lindsley

National Cave and Karst Management Symposium 2013

Virtual worlds, or 3D simulations through which an avatar can travel, is becoming a common means to display products or provide training in new environments. This paper describes the steps in producing the 3D virtual simulation of Snowy River in Fort Stanton Cave, New Mexico. A traditional cave survey and map with cross sections was used to produce a 3D meshed surface of the cave walls using the Blender software package. Photographs were taken of the walls, ceiling, and floor and merged together. The merged montage was applied to the 3D mesh walls as a “texture”. Unity3D was used to …


Wallace And Incipient Structures: A World Of "More Recondite" Influences, Charles H. Smith Nov 2013

Wallace And Incipient Structures: A World Of "More Recondite" Influences, Charles H. Smith

DLPS Faculty Publications

Alfred Russel Wallace is well-known for his co-discovery of the principle of natural selection. Natural selection is usually considered a process, but it is not clear that Wallace regarded it in exactly these terms. In fact he more likely thought of the relationships involved as representing what we would now term a “state space,” a negative feedback loop wherein populations are maintained at healthy levels through elimination of the unfit. Both before and after the advent of natural selection Wallace clung to the idea that “more recondite forces” were shaping the nature and direction of evolution; this is especially evident …


Ce-Qual-W2 Model And Model Set-Up, Scott A. Wells Nov 2013

Ce-Qual-W2 Model And Model Set-Up, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Conference presentation that provides background information on the CE-QUAL-W2 water modeling software, with examples of its use and instructions on set-up and application.


2014 Weed Control Recommendations For Kentucky Grain Crops, Jonathan D. Green, James R. Martin Nov 2013

2014 Weed Control Recommendations For Kentucky Grain Crops, Jonathan D. Green, James R. Martin

Agriculture and Natural Resources Publications

The use of herbicides suggested in this publication is based on research at the Kentucky Agricultural Experiment Station and elsewhere. We have given what we believe to be the most effective herbicides, with the most suitable rates and times of application. Use of trade or brand names in this publication does not imply approval of the product to the exclusion of others which may be of similar or suitable composition.

Herbicide registrations and labels are constantly being revised and changed; therefore, herbicides recommended in this publication were registered for the prescribed uses when the publication was printed. If the registration …


Can We Graze 300+ Days?, Glen Aiken Oct 2013

Can We Graze 300+ Days?, Glen Aiken

Kentucky Grazing Conference

Dependence on stored feeds during the winter months has been necessary in order to maintain body condition and meet nutrient requirements of cattle herds; unfortunately, cost of stored feeds typically are a major part of the farm budget. We know, all too well, that hay shortages and unstable feed ingredient markets have reduced profit potential in cattle production. This has further placed higher demands on supplies of co-product feeds to cause prices of these alternative feeds to rise and make them less cost effective. There will likely be less reliance on concentrate and co-product feeds as the forage-based livestock industry …


Pastures For Horses, Robert Coleman Oct 2013

Pastures For Horses, Robert Coleman

Kentucky Grazing Conference

The horse evolved as a grazing animal. In order to consume enough forage to meet the horses’ nutritional needs a significant amount of time would be spent each day grazing. The pattern of selecting forage-moving to the next area starting to graze again can easily translate into 14 to 16 hours of grazing activity each day. The level of grazing activity will also be affected by the available forage and the daily access to pasture.


Pastures For Goats And Sheep, Greg Brann Oct 2013

Pastures For Goats And Sheep, Greg Brann

Kentucky Grazing Conference

Pasture for sheep is not that different than that for cattle but pasture for goats is very different. Sheep are grazers like cattle whereas goats are browsers like deer. Even though grass and clover are not a goats preference if all of the forage present is grass and clover goats will eat it. Due to goats and sheep being more prey animals than cattle they don’t like to wade off into tall vegetation, also it takes more energy for them to move through tall growth. Many plants that we traditionally consider weeds become desirable forbs when goats or sheep are …


Role Of Legumes In Pastures, Garry D. Lacefield Oct 2013

Role Of Legumes In Pastures, Garry D. Lacefield

Kentucky Grazing Conference

Successful livestock production is dependent on forage programs which supply large quantities of adequate quality, homegrown feed. A major percentage of the feed units for beef (83%) and dairy (61%) cattle come from forages. In addition, forages supply an estimated 91%, 72%, 15% and 99% of the nutrients consumed by sheep and goats, horses, swine and ruminant wildlife, respectively.


A Source Of Terrestrial Organic Carbon To Investigate The Browning Of Aquatic Ecosystems, Jay T. Lennon, Stephen K. Hamilton, Mario E. Muscarella, A. Stuart Grandy, Kyle Wickings, Stuart E. Jones Oct 2013

A Source Of Terrestrial Organic Carbon To Investigate The Browning Of Aquatic Ecosystems, Jay T. Lennon, Stephen K. Hamilton, Mario E. Muscarella, A. Stuart Grandy, Kyle Wickings, Stuart E. Jones

Faculty Publications

There is growing evidence that terrestrial ecosystems are exporting more dissolved organic carbon (DOC) to aquatic ecosystems than they did just a few decades ago. This “browning” phenomenon will alter the chemistry, physics, and biology of inland water bodies in complex and difficult-to-predict ways. Experiments provide an opportunity to elucidate how browning will affect the stability and functioning of aquatic ecosystems. However, it is challenging to obtain sources of DOC that can be used for manipulations at ecologically relevant scales. In this study, we evaluated a commercially available source of humic substances (“Super Hume”) as an analog for natural sources …


Geogram 2013, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2013

Geogram 2013, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Observation-Based Algorithm Development For Subsurface Hydrology In Northern Temperate Wetlands, Chun-Mei Chiu Oct 2013

Observation-Based Algorithm Development For Subsurface Hydrology In Northern Temperate Wetlands, Chun-Mei Chiu

Open Access Dissertations

This study investigates wetland subsurface hydrology, as well as biogeochemistry - which is strongly influenced by water and temperature dynamics - as these interactions are expected to be highly significant, yet remain poorly represented in current ecosystem and climate models.

Northern wetlands have received widespread public attention due to steadily increasing summer mean global temperatures, extreme precipitation events and higher rates of natural greenhouse gas emissions, as well as the significant impacts on them due to human activities. The goal of my graduate research has been to improve quantification of the role of subsurface hydrology in northern wetlands by using …


Droughtscape, Fall 2013, National Drought Mitigation Center Oct 2013

Droughtscape, Fall 2013, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Director’s report

Kansas community drought planning workshop November 5

Drought impacts webinars

Drought outlook and summary

Late summer drought brings more agricultural impacts

Plans help ranchers weather drought

NDMC contributions to U2U project

Drought Management Database archives strategies

QuickDRI will help spot flash droughts

NDMC Co-Hosts NASA workshop

Wilhite leads Integrated Drought Management Program work

Speaking of drought

Managing #Drought tweet chat transcript

Updated USDM website


Single And Multi-Date Landsat Classifications Of Basalt To Support Soil Survey Efforts, Jessica J. Mitchell, Rupesh Shrestha, Carol A. Moore-Ellison, Nancy F. Glenn Oct 2013

Single And Multi-Date Landsat Classifications Of Basalt To Support Soil Survey Efforts, Jessica J. Mitchell, Rupesh Shrestha, Carol A. Moore-Ellison, Nancy F. Glenn

Geosciences Faculty Publications and Presentations

Basalt outcrops are significant features in the Western United States and consistently present challenges to Natural Resources Conservation Service (NRCS) soil mapping efforts. Current soil survey methods to estimate basalt outcrops involve field transects and are impractical for mapping regionally extensive areas. The purpose of this research was to investigate remote sensing methods to effectively determine the presence of basalt rock outcrops. Five Landsat 5 TM scenes (path 39, row 29) over the year 2007 growing season were processed and analyzed to detect and quantify basalt outcrops across the Clark Area Soil Survey, ID, USA (4,570 km2). The …


Nitrogen And Potassium Dynamics Of Selected Indiana Soils, Chun Zhao Oct 2013

Nitrogen And Potassium Dynamics Of Selected Indiana Soils, Chun Zhao

Open Access Dissertations

Nitrogen (N) is the most limiting essential nutrient for crop growth. Numerous studies have been performed to improve N fertilizer recommendations. Accurate prediction of soil N supply has been found to be one of the most important factors that determine optimum fertilizer N rates. Seven soils collected from various locations across Indiana at four different depths were tested for N mineralization potential. Results showed that laboratory mineralizable N in the top layer (0-15 cm) of the seven soils ranged from 50 to 68 mg N kg-1 soil. In addition, more than 50% of the total mineralizable N was contributed from …


Peridynamic Modeling Of Coupled Mechanical Deformations And Transient Flow In Unsaturated Soils, Rami Jabakhanji Oct 2013

Peridynamic Modeling Of Coupled Mechanical Deformations And Transient Flow In Unsaturated Soils, Rami Jabakhanji

Open Access Dissertations

A coupled peridynamic model for mechanical deformations and transient moisture flow in unsaturated soils is developed. The model is capable of simulating the emergence and evolution of cracks triggered by volumetric strains in the soil which are associated with changes in moisture content. The development of our model is motivated by the need for a tool to analyze and evaluate the impact of dessication cracks on the movement of moisture and the mechanical properties of soils at the field scale. The model is based on the peridynamic reformulation of elasticity proposed by Silling for simulating the deformation of bodies with …


Phosphorus Cycling In Tropical Carbonate Sediment-Seagrass Systems, Zachary Howerton Oct 2013

Phosphorus Cycling In Tropical Carbonate Sediment-Seagrass Systems, Zachary Howerton

OES Theses and Dissertations

This thesis presents two studies focusing on phosphorus cycling in calcium carbonate sediments inhabited by seagrasses. Phosphorus is a major limiting nutrient for primary productivity in these sediments as well as in the overlying waters. In large part this is due to removal of phosphate from solution by adsorption and precipitation reactions.

In chapter II, the relationship between the size of the sedimentary phosphorus pool and the abundance of seagrass on the Great Bahama Bank, as well as the relationship between phosphorus content and grain size in the sediments, were examined to better understand the biogeochemistry of carbonate sediments and …


New Fossil Crinoids From The Early Mississippian (Kinderhookian) Wassonville Formation Of Southeast Iowa, Forest J. Gahn, Dr. Scott Ritter Sep 2013

New Fossil Crinoids From The Early Mississippian (Kinderhookian) Wassonville Formation Of Southeast Iowa, Forest J. Gahn, Dr. Scott Ritter

Journal of Undergraduate Research

The purpose of this paper is to document a newly discovered assemblage of Early Mississippian (Kinderhookian) fossil crinoids from southeast Iowa. I will provide an introduction and background of the project, followed by the results of the research. Cited references are included at the end of the report.


Report Card On Sustainable Natural Resource Use In Agriculture : Status And Trend In The Agricultural Areas Of The South-West Of Western Australia, Department Of Agriculture And Food, Western Australia Sep 2013

Report Card On Sustainable Natural Resource Use In Agriculture : Status And Trend In The Agricultural Areas Of The South-West Of Western Australia, Department Of Agriculture And Food, Western Australia

Books & book chapters

This report card summarises our current knowledge of the status and trend in the natural resource base in the agricultural areas of the south-west of Western Australia (WA) and provides a discussion of the implications for agricultural industries.

The condition of our natural resources is a complex interaction of numerous processes. In simple terms however, the performance of the land is driven by three primary factors: climate, land characteristics and land management. The first two factors are largely out of the control of land managers, and in a drying and variable climate, land management practices need to be able to …


City Of Tampa 2011 Urban Forest Analysis: The Structure, Composition, Function And Economic Benefits Of Trees And The Urban Forest, Shawn M. Landry, Robert J. Northrop, Madison Andreu, Carolyn Cheatham Rhodes Sep 2013

City Of Tampa 2011 Urban Forest Analysis: The Structure, Composition, Function And Economic Benefits Of Trees And The Urban Forest, Shawn M. Landry, Robert J. Northrop, Madison Andreu, Carolyn Cheatham Rhodes

School of Geosciences Faculty and Staff Publications

No abstract provided.


Assessing The Reliability Of Stable Isotopes In Fossil Bone: A Unique Case Study Of Prehistoric Lung Pathology., Kathleen Bundy, Samuel D. Matson Aug 2013

Assessing The Reliability Of Stable Isotopes In Fossil Bone: A Unique Case Study Of Prehistoric Lung Pathology., Kathleen Bundy, Samuel D. Matson

Student Research Initiative

Mammals at Ashfall Fossil Beds State Historical Park (NE Nebraska) offer a unique opportunity to test for the preservation of primary isotopic signatures in fossilized materials. At this site, large herbivores such as rhinoceroses, horses and camels are buried in volcanic ash sourced from an eruption of the Bruneau-Jarbridge caldera (Idaho/Nevada) ca. 11.8 million years ago. Most fossils from Ashfall display pathologic bone symptomatic of a lung disease (hypertrophic osteopathy or HPOA) likely related to inhalation of volcanic ash. In this study, we compare the stable oxygen isotopic composition (δ18O) of pathologic bone with that of normal cortical …


Revised Vertebral Count In The "Longest-Necked Vertebrate" Elasmosaurus Platyurus Cope 1868, And Clarification Of The Cervical-Dorsal Transition In Plesiosauria, Sven Sachs, Benjamin P. Kear, Michael J. Everhart Aug 2013

Revised Vertebral Count In The "Longest-Necked Vertebrate" Elasmosaurus Platyurus Cope 1868, And Clarification Of The Cervical-Dorsal Transition In Plesiosauria, Sven Sachs, Benjamin P. Kear, Michael J. Everhart

Sternberg Museum of Natural History Faculty Publications

Elasmosaurid plesiosaurians are renowned for their immensely long necks, and indeed, possessed the highest number of cervical vertebrae for any known vertebrate. Historically, the largest count has been attributed to the iconic Elasmosaurus platyurus from the Late Cretaceous of Kansas, but estimates for the total neck series in this taxon have varied between published reports. Accurately determining the number of vertebral centra vis-à-vis the maximum length of the neck in plesiosaurians has significant implications for phylogenetic character designations, as well as the inconsistent terminology applied to some osteological structures. With these issues in mind, we reassessed the holotype of E. …


Anticipating Stream Ecosystem Responses To Climate Change: Toward Predictions That Incorporate Effects Via Land–Water Linkages, J. M. Davis, C. V. Baxter, E. J. Rosi-Marshall, J. L. Pierce, B. T. Crosby Aug 2013

Anticipating Stream Ecosystem Responses To Climate Change: Toward Predictions That Incorporate Effects Via Land–Water Linkages, J. M. Davis, C. V. Baxter, E. J. Rosi-Marshall, J. L. Pierce, B. T. Crosby

Geosciences Faculty Publications and Presentations

Climate change (CC) is projected to increase the frequency and severity of natural disturbances (wildfires, insect outbreaks, and debris flows) and shift distributions of terrestrial ecosystems on a global basis. Although such terrestrial changes may affect stream ecosystems, they have not been incorporated into predictions of stream responses to CC. Here, we introduce a conceptual framework to evaluate to what extent responses of streams to CC will be driven by not only changes in thermal and hydrologic regimes, but also alterations of terrestrial processes. We focused on forested water-sheds of western North America because this region is projected to experience …