Digital Commons Network^™

Grazing Method: Tool Or Toolbox?, Garry D. Lacefield

Kentucky Grazing Conference

This conference makes the 15th consecutive year we have devoted a full day to Grazing. Kentucky is a great state for grazing animals since we have a relatively long pasture season, can grow many forage grasses and legumes and a long tradition of producing quality animal products from quality pasture. We have tremendous potential to improve our overall grazing efficiency and the discussion throughout the day will address many of the practical strategies for improvements.

Warming Reduces Tall Fescue Abundance But Stimulates Toxic Alkaloid Concentrations In Transition Zone Pastures Of The U.S., Rebecca L. Mcculley, Lowell P. Bush, Anna E. Carlisle, Huihua Ji, Jim A. Nelson

Plant and Soil Sciences Faculty Publications

Tall fescue pastures cover extensive acreage in the eastern half of the United States and contribute to important ecosystem services, including the provisioning of forage for grazing livestock. Yet little is known concerning how these pastures will respond to climate change. Tall fescue's ability to persist and provide forage under a warmer and wetter environment, as is predicted for much of this region as a result of climate change, will likely depend on a symbiotic relationship the plant can form with the fungal endophyte, Epichloë coenophiala. While this symbiosis can confer environmental stress tolerance to the plant, the endophyte …

Explosive Dome Eruptions Modulated By Periodic Gas-Driven Inflation, Jeffrey B. Johnson, J. J. Lyons, B. J. Andrews, J. M. Lees

Geosciences Faculty Publications and Presentations

Volcan Santiaguito (Guatemala) “breathes” with extraordinary regularity as the edifice's conduit system accumulates free gas, which periodically vents to the atmosphere. Periodic pressurization controls explosion timing, which nearly always occurs at peak inflation, as detected with tiltmeters. Tilt cycles in January 2012 reveal regular 26 ± 6 min inflation/deflation cycles corresponding to at least ~10¹ kg/s of gas fluxing the system. Very long period (VLP) earthquakes presage explosions and occur during cycles when inflation rates are most rapid. VLPs locate ~300 m below the vent and indicate mobilization of volatiles, which ascend at ~50 m/s. Rapid gas ascent feeds …

Relations Of Water-Quality Constituent Concentrations To Surrogate Measurements In The Lower Platte River Corridor, Nebraska, 2007 Through 2011, Nathaniel J. Schaepe, Philip J. Soenksen, David L. Rus

United States Geological Survey: Water Reports and Publications

The lower Platte River, Nebraska, provides drinking water, irrigation water, and in-stream flows for recreation, wildlife habitat, and vital habitats for several threatened and endangered species. The United States Geological Survey (USGS), in cooperation with the Lower Platte River Corridor Alliance (LPRCA) developed site-specific regression models for water-quality constituents at four sites (Shell Creek near Columbus, Nebraska [USGS site 06795500]; Elkhorn River at Waterloo, Nebraska [USGS site 06800500]; Salt Creek near Ashland, Nebraska [USGS site 06805000]; and Platte River at Louisville, Nebraska [USGS site 06805500]) in the lower Platte River corridor. The models were developed by relating continuously monitored water-quality …

The Relationship Between Environmental Factors And Cyanobacteria Population In Lake Bloomington And Evergreen Lake In Mclean County, Illinois, Matthew Douglas Meyers

Theses and Dissertations

This thesis investigates cyanobacteria on two lakes in McLean County, Illinois from the months of August to October. Data was collected every other week.Cyanobacteria are prokaryotes that may be unicellular, colonial or filamentous in form. These cells can be known to be toxic or non-toxic. The factors that control the reproduction of cyanobacteria are the temperature and nutrients of nitrogen and phosphorus. These microorganisms are located in marine and terrestrial settings worldwide. The focus of this study was at two man-made lakes which are Lake Bloomington and Lake Evergreen. Sampling and collection of data was done on two lakes to …

Microbial Water Quality During The Northern Migration Of Sandhill Cranes (Grus Canadensis) At The Central Platte River, Nebraska, Matthew T. Moser

United States Geological Survey: Water Reports and Publications

The central Platte River is an important resource in Nebraska. Its water flows among multiple channels and supports numerous beneficial uses such as drinking water, irrigation for agriculture, groundwater recharge, and recreational activities. The central Platte River valley is an important stopover for migratory waterfowl and cranes, such as the Whooping Cranes (Grus americana) and Sandhill Cranes (Grus canadensis), in their annual northward traversal of the Central Flyway. Waterfowl, cranes, and other migratory birds moving across international and intercontinental borders may provide long-range transportation for any microbial pathogen they harbor, particularly through the spread of feces. …

The Effects Of Altitude And Micro-Spatial Habitats On The Physiognomic Characteristics Of Syzygium Guineense In Mazumbai Forest Reserve, Erin Brynn Zalmanek

Independent Study Project (ISP) Collection

In order to examine the affects that altitude and micro-spatial habitat have on the physiognomy of Syzygium Guineense; buttress sphere size, number of buttresses, relative size of the buttresses, DBH, and height were measured in three different altitudinal bands (1400 - 1500 m, 1500 - 1600 m, and 1600 - 1700 m) and three different habits portraying concave, convex, and intermediate landscapes. Micro-spatial habits showed to have weak to no effect on all measured physiognomic variables giving insignificant p-values according to ANOVA. However, correlation tests against leaf litter depth and slope showed to have some relation to the size and …

Droughtscape, Fall 2014, Kelly Smith

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

Contents

Director’s report

Upcoming events

Drought and climate summary

Drought impacts

Drought planning in Brazil

Ethiopian workshop

Visiting scholar

Help for South Plains ranchers

Wind River tribal workshop

Inter Tribal Buffalo Council

South Dakota ranch workshops

Liquid Swine Manure Application Timing And Instincttm Impacts On Net Soil Nitrogen Mineralization And Corn Yield, Min Xu

Open Access Theses

Nitrogen (N) is one of the most expensive variable input costs for corn production. Optimized manure management is essential to ensure maximum crop N utilization and to reduce the risk of N loss. A field study was conducted in central Indiana from 2011-2013 to assess liquid swine ( Sus scrofa L.) manure N availability when applied at different times or co-applied with InstinctTM , a microencapsulated form of nitrapyrin. Soil inorganic N contents, soil N mineralization, corn yield, grain N content, whole plant N concentrations of corn at the V6 growth stage, and ear leaf N concentrations of corn at …

Soil Quality And Nitrogen Cycling Dynamics Altered By Fertility Amendments In Intensively Managed Vegetable Production Systems, Matt A. Rudisill

Open Access Dissertations

Fresh market vegetable production in the Midwest U.S. is growing rapidly as a result of increased demand for locally-sourced food. High tunnels are becoming increasingly popular among Midwest vegetable growers as these structures offer many production benefits including season extension. However, vegetables require substantial fertility inputs, particularly nitrogen (N), in order to meet desired levels of productivity, and some fertility management strategies can negatively impact soil and environmental quality. This can be particularly problematic in high tunnels, where longer production periods and modification of the growing environment put these systems at greater risk for soil degradation. Identification of fertility practices …

A New Passive Surface Water Flux Meter For Simultaneous Measurement Of Contaminant And Water Fluxes In Streams And Rivers, Stephen A. Sassman

Open Access Dissertations

A passive surface water flux meter (PSFM) for measurement of contaminant concentration/flux in rivers and streams is described and tested. The novel PSFM design was developed for portability and ease of adaptability for a variety of contaminant classes. Although previous designs have been evaluated under constant flow conditions, the PSFM has never been used for measurement of pesticides or hormones and this is the first time that it has been tested under transient flow. Discharge through the PSFM is assessed by measuring miscible displacement of alcohol tracers from granular activated carbon (GAC). The tracer retardation factors (R) measured by miscible …

The Interaction Between Arsenic And Struvite During Coprecipitation And Adsorption Processes, Ning Ma

Dissertations, Theses, and Capstone Projects

The formation of struvite, MgNH4PO4*6H2O (MAP), from wastes is one of the methods that can be used to recover P from wastes efficiently. However, since there are usually toxic components in the wastes, like arsenic (As), the possibility of having toxic contaminants in MAP is a big concern. So, the interaction between As and MAP during coprecipitation (CPT) and adsorption (ADS) processes were studied at pH 8-11. MAP precipitated without As at pH 8-11 was also characterized.

During CPT process, the MAP was precipitated from a MgCl2-(NH4)2HPO4-NaCl-H2O system spiked with As at an initial pH (pHi) of 8-11. The batch …

Hydro-Climate Temporal Variations And Their Influences On Net Primary Production In A Eurasian Steppe Watershed, Xiaomin Yang

Civil & Environmental Engineering Theses & Dissertations

Climate, which is the most important factor that influences Net Primary Productivity, has been detected changing all over the world. The confounding effects of step change invalidate the stationarity assumption of commonly used trend analysis methods such as the Mann-Kendall test technique, so previous studies have failed to explain inconsistencies between detected trends and observed large anomalies. In this research, by formulating a trend analysis approach that considers nonstationary due to step changes, trends and extreme occurrences of precipitation, temperature, and runoff in annual, seasonal, and monthly scales were analyzed in a mid-latitude Eurasian steppe watershed in northeast China, and …

Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Cheatgrass (Bromus tectorum) is one of the most problematic invasive plant species in North America and climate change threatens to exacerbate its impacts. We conducted a two‐year field experiment to test the effect of warming, competition, and seed source on cheatgrass performance across an elevation gradient in northern Utah. We hypothesized that warming would increase cheatgrass performance, but that warming effects would be limited by competing vegetation and by local adaptation of cheatgrass seed sources. The warming treatment relied on open top chambers, we removed vegetation to assess the effect of competition from neighboring vegetation, and we reciprocally …

Age Of Barrier Canyon-Style Rock Art Constrained By Cross-Cutting Relations And Luminescence Dating Techniques, Joel L. Pederson, Harriet Cornachione, Steven R. Simms, Reza Sohbati, Tammy M. Rittenour, Andrew S. Murray, Gary Cox

Geosciences Faculty Publications

Rock art compels interest from both researchers and a broader public, inspiring many hypotheses about its cultural origin and meaning, but it is notoriously difficult to date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are among the most debated examples; hypotheses about its age span the entire Holocene epoch and previous attempts at direct radiocarbon dating have failed. We provide multiple age constraints through the use of cross-cutting relations and new and broadly applicable approaches in optically stimulated luminescence dating at the Great Gallery panel, the type section of BCS art in Canyonlands National Park, southeastern Utah. Alluvial …

Sedimentology Of Marine Vertebrate Burial In The Miocene Pisco Fm., Peru, Monte A. Fleming

Loma Linda University Electronic Theses, Dissertations & Projects

The Miocene Pisco Basin of Peru is known for abundant, well-preserved marine vertebrate fossils (Esperante et al. 2000). Cetacean fossils are particularly abundant—so much so that we were able to locate 10 outcrops containing specimens in cross section, which allowed us to do detailed sedimentological studies of the beds surrounding the whales. We discovered that six of the 10 specimens were buried in channels; the details of the other four burials are too disparate to meaningfully group together in categories. Chapters 3, 4, and 5 describe and discuss the six specimens found in channels, while Appendix A contains descriptions and …

Understanding And Assessing Climate Change: Implications For Nebraska, Deborah J. Bathke, Robert J. Oglesby, Clinton Rowe, Donald A. Wilhite

Department of Earth and Atmospheric Sciences: Faculty Publications

This report was commissioned by the UNL Institute of Agriculture and Natural Resources (IANR) with the objective of evaluating and summarizing the existing scientific literature related to our changing climate. Scientists from the IANR’s School of Natural Resources and the Department of Earth and Atmospheric Sciences in the College of Arts and Sciences have been the principal contributors to the report under the able leadership of long-time, internationally leading applied climate scientist Professor Don Wilhite. Their efforts have resulted in a timely and seminal reference for state and local policy-makers, government agency leaders, private industry, and indeed all citizens of …

Discovery Of Shallow-Marine Biofacies Conodonts In A Bioherm Within The Carboniferous-Permian Transition In The Omalon Massif, Ne Russia Near The North Paleo-Pole: Correlation With A Warming Spike In The Southern Hemisphere, Vladimir I. Davydov, Alexander S. Biakov

Geosciences Faculty Publications and Presentations

The conodont genera Hindeodus and Streptognathodus are reported for the first time within the Carboniferous-Permian transition in the northern high latitudes of the Paren’ River, Omolon Massif, NE Russia. Several fossil groups, including brachiopods, bivalves, scaphopods and microgastropods were found to be prolific in the invertebrate-dominated bioherms. These bioherms occur within predominantly siliciclastic sequences with extremely poor fauna, whereas in the studied bioherms the diversity of the bivalves and brachiopods exceeded observed diversity elsewhere in coeval facies in NE Russia. The bioherms are biostratigraphically constrained as uppermost Pennsylvanian to lowermost Cisuralian based on ammonoids. The very unusual peak of bivalve …

Genes Mediating Cardiac Remodeling During Pregnancy And The Early Post-Partum-Period In Mice, Esam Aljrbi

Theses and Dissertations

The female heart undergoes adaptive remodeling during pregnancy to compensate for the increased hemodynamic load imposed by the developing fetus. However, unlike a similar adaptive process which occurs under pathological conditions (such as hypertension and valvular heart disease) the cardiac changes observed during hypertrophy associated with pregnancy are reversible. The goal of this study is to identify changes in gene expression associated with pregnancy-induced hypertrophy. We tested the hypothesis that pregnancy-induced physiological hypertrophy has a unique genetic signature, likely due to altered hormone levels, which supports and promotes reversible remodeling. Comparing the gene expression profile associated with physiological remodeling with …

Assessment Of Salmon Habitat On The Feather River, Nathan Sweem

STAR Program Research Presentations

Human activity in central valley streams has had a significantly negative impact on salmon habitat (Williams 2006). The presence of dams impedes sediment transport which is critical to salmon spawning (Williams 2006; Kondolf 1997). As part of an effort to enhance salmon spawning, the California Department of Water Resources added 7000 ft³ of gravel to Cottonwood Hatchery, Upper Auditorium, and Auditorium riffles on the Lower Feather River below the Thermalito Dam Complex in July of 2014. Stream conditions at Cottonwood Hatchery riffle were assessed by conducting analysis of sediment grain size, water depth and velocity, gravel permeability, and dissolved …

Evaluating The Effectiveness Of Regulatory Stormwater Monitoring Protocols On Groundwater Quality In Urbanized Karst Regions, Daniel C. Nedvidek

Masters Theses & Specialist Projects

Non-point pollution from stormwater runoff is one of the greatest threats to water quality in the United States today, particularly in urban karst settings. In these settings, the use of karst features and injection wells for stormwater management results in virtually untreated water being directed into the karst aquifer. Currently, no policies exist specifically to provide water quality protections to karst environments. This study utilized a combination of karst stormwater quality data, along with survey data collected from MS4 Phase II communities, and an analysis of current federal, local, and state water quality regulations, to assess the need for karst-specific …

Are Local Filters Blind To Provenance? Ant Seed Predation Suppresses Exotic Plants More Than Natives, Dean Pearson, Nadia S. Icasatti, Jose L. Hierro, Benjamin J. Bird

Biological Sciences Faculty Publications

The question of whether species’ origins influence invasion outcomes has been a point of substantial debate in invasion ecology. Theoretically, colonization outcomes can be predicted based on how species’ traits interact with community filters, a process presumably blind to species’ origins. Yet, exotic plant introductions commonly result in monospecific plant densities not commonly seen in native assemblages, suggesting that exotic species may respond to community filters differently than natives. Here, we tested whether exotic and native species differed in their responses to a local community filter by examining how ant seed predation affected recruitment of eighteen native and exotic plant …

Investigation Of The Flow And Fate Of Nitrate In Epikarst At The Savoy Experimental Watershed, Northwest Arkansas, Jozef Laincz

Graduate Theses and Dissertations

Many karst aquifers are at high risk of nitrate contamination due to a combination of vulnerable geology characterized by thin soils and conduit flow, and excess inputs of nutrients from animal feeding operations. One zone that is present in many karst regions and could play an important role in nitrate attenuation due to properties such as increased residence time and matrix-water contact is the upper, weathered portion of karst, the epikarst. However, the understanding of this role is lacking, and the objective of this dissertation was to elucidate it. The fate of nitrate in the epikarst was traced along a …

Michigan's Clay Bluffs: The Description And Comparison Of An Erosion-Dependent Natural Community, Nathaniel G. Fuller

Masters Theses

The clay bluffs of Michigan are a natural community found along the shores of the Great Lakes. Groundwater is found to be critical to sustaining the alkaline wetlands on the face of the bluff as well as the source of most erosion events. The clay bluffs are unusual in their vegetation, disturbance regime and geographical context. This thesis focuses primarily on describing seeping clay bluffs and exploring the comparison to other natural communities. The purpose of this is twofold, to better understand the ways in which natural communities are described as distinct from one another, and to assess the distinctness …

Full Proceedings Of The 6th International Workshop On Ice Caves, National Cave And Karst Research Institute

The International Workshop on Ice Caves

Welcome to the Sixth International Workshop on Ice Caves (IWIC VI) in Idaho Falls, Idaho, USA. The National Cave and Karst Research Institute is pleased to host the first IWIC to meet outside of Europe, which will include speakers from over half a dozen countries in Europe, Asia, and North America. The conference setting in this mountainous region of the northwestern United States will provide conference participants with multiple opportunities to visit ice caves, including two trips to Craters of the Moon National Monument. This is also the first IWIC to examine ice in lava tube caves.

On The Mechanism Of The Naturally Formed Ice Spikes, Hi-Ryong Byun, Chang-Kyun Park

The International Workshop on Ice Caves

The formations of the ice spike, which is the ice bar risen upward from the ice surface in bowl and has been known as a mystery of the Mt. Mai in Jinan, Jeonbuk Korea, are observed and analyzed through the observation records on more than 60,000 bowls of water for 8 years and 7 days and nights' consecutive meteorological observations. Experiments making the ice bar in the refrigerator have also performed. As results, it is verified that the ice spike is not a mystery but a naturally grown ice bar caused by the volume expansion centralized to a certain point …

The Influence Of Karst Topography To Ice Cave Occurrence - Example Of Ledena Jama In Lomska Duliba (Croatia), Nenad Buzjak

The International Workshop on Ice Caves

The research of cave microclimate in general contributes to a better understanding of physical and chemical processes in complex karst geoecosystems. Special challenges for researchers are ice caves. This preliminary report is a part of the project dedicated to the research of deep caves on Velebit Mt. and pointed to the influence of the large karst depression microclimate to cave microclimate, e.g. ice and snow accumulation. The one year study using T/RH data loggers was conducted in Lomska duliba valley (Velebit Mt.) known for frequent temperature inversion and low air temperature, and in partially ice-snow filled Ledena jama (Ice shaft) …

Tempo And Mode Of Domestication During The Neolithic Revolution: Evidence From Dental Mesowear And Microwear Of Sheep, Melissa Zolnierz

Graduate Theses and Dissertations

The Neolithic Revolution marked a dramatic change in human subsistence practices. In order to explain this change, we must understand the motive forces behind it. Researchers have proposed many different stimuli, with most theories invoking environmental dynamics, human population density increases beyond environmental carrying capacity, and the natural outgrowth of human and plant/animal interactions. However, unanswered questions remain concerning the mechanics of animal domestication. Traditional studies of changing faunal morphology and skeletal population profiles offer some clues, but such research has had limited success identifying stages intermediate between wild and domesticated forms, which makes it difficult to discern initial attempts …

Integrating Land Cover Modeling And Adaptive Management To Conserve Endangered Species And Reduce Catastrophic Fire Risk, David Breininger, Brean Duncan, Mitchell Eaton, Fred Johnson, James Nichols

United States Geological Survey: Staff Publications

Land cover modeling is used to inform land management, but most often via a two-step process, where science informs how management alternatives can influence resources, and then, decision makers can use this information to make decisions. A more efficient process is to directly integrate science and decision-making, where science allows us to learn in order to better accomplish management objectives and is developed to address specific decisions. Co-development of management and science is especially productive when decisions are complicated by multiple objectives and impeded by uncertainty. Multiple objectives can be met by the specification of trade offs, and relevant uncertainty …

Using Temporal Changes In Drought Indices To Generate Probabilistic Drought Intensification Forecasts, Jason A. Otkin, Martha C. Anderson, Christopher Hain, Mark Svoboda

National Drought Mitigation Center: Faculty Publications

In this study, the potential utility of using rapid temporal changes in drought indices to provide early warning of an elevated risk for drought development over subseasonal time scales is assessed. Standardized change anomalies were computed each week during the 2000–13 growing seasons for drought indices depicting anomalies in evapotranspiration, precipitation, and soil moisture. A rapid change index (RCI) that encapsulates the accumulated magnitude of rapid changes in the weekly anomalies was computed each week for each drought index, and then a simple statistical method was used to convert the RCI values into drought intensification probabilities depicting the likelihood that …