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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
871

Prediction of Suburban Encroachment on the Ethan Allen Firing Range and Camp Johnson, Chittenden County, Vermont

Calandrelli, John D. 01 May 1999 (has links)
Suburban encroachment is a growing concern for many National Guard training installations. The Ethan Allen. Firing Range and Camp Johnson, Vermont, are either experiencing or are completely enclosed by urban encroachment. The objective of this study was to analyze the trends of suburban growth within Chittenden County, Vermont, to evaluate growth and explore future training site viability of the Ethan Allen Firing Range and Camp Johnson. This study focused on historical data, recent real estate transactions, population projections, and county plans for growth. Using historical and contemporary data, I developed a predictive model of suburban encroachment on Camp Johnson and the Ethan Allen firing Range facilities by residential and commercial development. This model may assist land managers make decisions and illustrate the viability of these installations as National Guard training sites. This model may also be applied to other installations with similar concerns.
872

Environmental Analysis of the Upper Cambrian Nounan Formation, Bear River Range and Wellsville Mountain, North-Central Utah

Gardiner, Larry L. 01 May 1974 (has links)
The Nounan Formation in north-central Utah thickens northward from 696 feet near Causey Dam to 1147 feet at High Creek in the Bear River Range, and northwestward to 1149 feet at Dry Canyon in Wellsville Mountain. The basal contact of the Nounan Formation is sharp, but dolomite extends irregularly downward into limestones of the Bloomington Formation as much as 6 feet. The Nounan Formation is divided into three members based on lithologic characters: (1) a lower member composed of dark, medium-crystalline dolomite; (2) a middle member composed of white, coarse-crystalline dolomite with tongues of dark dolomite; and (3) an upper member of interbedded light and dark dolomites and limestones with local arenites and sandy carbonates. The lower member was deposited in a high-energy, shallow-marine subtidal to intertidal environment. Evidence includes sets of low-angle cross stratification (dunes), oncolites, oolites, and rip-up clasts. The middle member forms distinctive ledges and cliffs. The presence of thinly laminated algal stromatolites and relict structures seen also in the lower member indicate a subtidal to intertidal environment similar to that inferred for the lower member. The white color and coarse crystallinity may have resulted from recrystallization of the dark, finer grained dolomite that comprises the lower member. The upper member is characterized by lithologic variability. Thicknesses of limestone are greatest in the north, and decrease to only a few feet in the south. Quartz and other terrigenous minerals are scattered at intervals throughout the upper member, with a marker of sandy (arenaceous) dolomites at the base and near the middle and an increase of sand near the top also. The upper contact, with quartz-rich arenites (subarkosic quartzites) of the Worm Creek Member of tho St. Charles Formation, is gradational overall, but is sharp and planar in each section and readily located. In the upper member, algal mats trapped a varying but overall increasing influx of quartz and feldspar, probably in shallow subtidal environments, and vertically stacked hemispheroids suggest that depositional conditions may have included intertidal. Virtually all of the dolomite in the Nounan Formation must have formed by replacement of lime sediments by downward-moving high-magnesium brines. It is that these brines originated in restricted, shallow, subtidal evaporating basins, such as the Great Bahama Banks today, and associated supratidal flats. Lateral changes from limestone to dolomite overall and also in individual beds of the upper member indicate that the brines travelled laterally as well as vertically, and dolomitization may have been limited as much by prior diagenetic alteration and cementation as by the volume, concentration, and proximity of the brine itself.
873

Land Use Dynamics and Implications for Water Management in the Urbanizing Wasatch Range Metropolitan Area of Utah

Li, Enjie 01 December 2017 (has links)
Utah is one of the fastest growing states in the USA. Utah’s Wasatch Range Metropolitan Area (WRMA), where 80% of Utah’s population resides, is growing at unprecedented rates and has seen extensive urban landscape transformation in the last half century. Many of Utah’s agricultural lands, grasslands, and wetlands have been transformed into urban areas during this time. Local residents have watched and experienced these changes to their local environment, but without a clear understanding of the processes and impacts of urbanization. It is not until we study these landscapes from a spatial perspective and the time scale of decades that we can begin to measure the changes that have occurred and predict the impact of changes to come if current trajectories continue. In this dissertation research I worked with my research colleagues to provide a comprehensive analysis of the WRMA’s past land use changes and future land use trends. In doing so, we: (1) measured the rate, the magnitude, and the process of past urban growth; (2) compared the changes of irrigated agricultural lands and non-irrigated agricultural lands in relation to urban development; and, (3) predicted how future urban growth could occur under various policy scenarios. We found that several counties at the heart of the WRMA have reached the limits of their capacity for future urban expansion. Thus, increasing urban density and land use efficiency will be key aspects of addressing the WRMA’s future growth. Also, variations of growth trends exist among and within the ten counties located in the WRMA, so it is necessary to develop contextualized and localized growth management plans. Furthermore, past land use dynamics prove that irrigated agricultural lands are more affected by urbanization than non-irrigated agricultural lands, with evidence of increasing agricultural lands fragmentation. Agricultural lands have been and will likely continue to be the major land source for future urban development. Utah’s public has indicated it wants to preserve agricultural lands to maintain open space and preserve cultural heritage, but this will require political attention and actions focused on areas where these lands are particularly vulnerable in the face of urban growth trajectories. The overall dissertation provides quantitative measurement of Utah’s urban landscape transformation and a science-based foundation for crafting successful land use policies to help guide future growth of the WRMA.
874

Influence Of Fall Grazing By Sheep On Plant Productivity, Shrub Age Class Structure And Herbaceous Species Diversity In Sagebrush Steppe

Woodland, Ryan Duncan 01 May 2004 (has links)
Managing Wyoming Big Sagebrush (Artemisia tridentata ssp. wyomingensis) systems biologically with grazing can potentially reduce costs and increase both biodiversity and understory production as well as rejuvenate Wyoming Big Sagebrush (ARTRWY). Sheep were provided a protein-energy supplement to facilitate use of the secondary metabolites found in ARTRWY forage. Phytomass ( ) was estimated for the following plant categories: total phytomass, current annual growth (CAG) of ARTRWY, the woody portion of ARTRWY, CAG of other shrubs, the woody portion of other shrubs, grasses, forbs, litter, and standing dead material. I also measured plant species richness and abundance, as well as estimates of the age class structure of sagebrush. One year following grazing, total phytomass decreased by 43%, due primarily to the reduction of ARTRWY. The CAG of ARTRWY decreased by 66%, while grasses increased by 43%, forbs increased 60%, and the number of species encountered in the grazed plots increased 42%.
875

Evolution of a Miocene-Pliocene Low-Angle Normal-Fault System in the Southern Bannock Range, Southeast Idaho

Carney, Stephanie M. 01 May 2002 (has links)
Geologic mapping, basin analysis, and tephrochronologic analysis in the Clifton quadrangle of southeast Idaho indicates that the modern Basin-and-Range topography is only a few million years old and that the bulk of Cenozoic extension was accommodated by slip on an older low-angle normal-fault system, the Bannock detachment system. The detachment system was active between ~12 and < 4 Ma and accommodated ~50 % extension. Cross-cutting relationships show that the master detachment fault, the Clifton fault, is the youngest low-angle normal fault of the system, was active at a low angle, and has not been rotated to a low-dip angle through time. Map patterns and relationships indicate that the hanging wall to the detachment system began as a cohesive block that later broke up along listric and planar normal faults that either sole into or are cut by the master detachment fault. The Miocene-Pliocene Salt Lake Formation, a syntectonic, basin-fill deposit of the Bannock detachment system, was deposited during three sub-episodes of extension on the detachment system. Depositional systems within the Salt Lake Formation evolved from saline/alkaline lakes to fresh water lakes and streams to braided streams in response to the changing structural configuration of rift basins in the hanging wall of the detachment system. After breakup of the hanging wall began, the master detachment fault excised part of the hanging wall and cut hanging-wall deposits and structures. The structural geometry of the Bannock detachment system strongly resembles that of detachments documented in metamorphic core complexes. Therefore, we interpret the Bannock detachment system as a proto-metamorphic core complex, akin to the Sevier Desert detachment fault. The Bannock detachment system also collapsed the Cache-Pocatello culmination of the dormant Sevier fold-and-thrust belt, much like the Sevier Desert detachment collapsed the Sevier culmination. Structures of the Bannock detachment system are overprinted by a second episode of extension accommodated by E- and NE-trending normal faults that may be related to subsidence along the Yellowstone hotspot track and a third episode of extension accommodated by high-angle, Basin-and-Range normal faults. This last episode of extension began no earlier than 4-5 Ma and continues today.
876

Self-Medicative Behavior of Sheep Experiencing Gastrointestinal Nematode Infections and the Postingestive Effects of Tannis

Lisonbee, Larry D 01 December 2008 (has links)
Diet selection and self-medication are fundamental to the survival of all species. The abilities to choose healthy foods in response to past consequences are basic elements of evolution. This study explores self-medication regarding tannins both as a medication and as a dietary challenge. In the first study, sheep with natural parasite infections were offered a low quality supplement containing a dose of tannins considered to be therapeutic (medicine), while the control infected lambs received the same supplement without tannins (placebo). This study included a group of parasite-free lambs. The parasitized lambs ate more of the tannin containing supplement than non-parasitized lambs for the first 12 d of the study, when parasite burdens were high, but differences became smaller and disappeared towards the end of the study when parasite burdens decreased. This result indicated lambs ability to detect the presence of internal parasites and to learn to ingest tannin when followed by relief from parasite burdens.In the second study, lambs grazed on pastures with forages containing saponins (alfalfa),iiialkaloids (endophyte-infected tall fescue) and tannins (birdsfoot trefoil). I observed the foraging behavior of groups of lambs after intra-ruminal infusions of tannins (treatment). Lambs that first received intraruminal infusions of tannins and then were offered 2-way choices between varieties of forages with high and low concentrations of either saponins, alkaloids, or tannins increased their preference for the high-saponin variety of alfalfa and the high-alkaloid variety of tall fescue relative to lambs not infused with tannins (controls). Lambs infused with tannins and offered choices among the 3 forages with high concentrations of secondary compounds also manifested higher preference for the high-alkaloid variety of tall fescue than control lambs. In contrast, lambs infused with tannin reduced their preference for the high-tannin variety of birdsfoot trefoil.This research has implications for many situations where forages with secondary compounds are available but underutilized. Landscapes where such forages are available could be used effectively with little or no harm to livestock if medicinal forages or supplements are made available and offered as alternatives so animals can learn about their benefits of chemical complementarities among different plant species.
877

Nutritive Values of Russian Wildrye, Crested Wheatgrass, and Intermediate Wheatgrass Grazed by Cattle on Utah Foothill Ranges

Mitchell, George W. 01 May 1969 (has links)
A comparative index to digestible nutrients was established for Russian wildrye, crested wheatgrass, and intermediate wheatgrass seeded on foothill areas of Utah. The nutritive values of these grasses were compared by the lignin ratio method, the chlorophyllan ratio method, and the in vivo rumen bag process. Average digestion coefficients computed by the lignin ratio method for dry matter, ether extract, cellulose, and gross energy were highest for intermediate wheatgrass. Protein was more digestible for Russian wildrye. Digestible energy was adequate in all species to meet requirements for late lactation. Results from the chlorophyllan ratio method were excessively high and were not considered valid. Dry matter loss of Russian Wildrye was greater than losses from either of the wheatgrasses. Losses of dry matter due to 24-hour in vivo rumen fermentation and rinsing only of nylon bags were closely correlated.
878

Risk and Climate at High Elevation: A Z-score Model Case Study for Prehistoric Human Occupation of Wyoming's Wind River Range

Losey, Ashley K 01 May 2013 (has links)
Holocene climate likely influenced prehistoric hunter-gatherer subsistence and mobility as changing climate patterns affected food resources. Of interest here is whether climate-driven resource variability influenced peoples in the central Rocky Mountains. This study employed the z-score model to predict how foragers coped with resource variability. The exercise enabled exploration of the relationship between climate, resources, and foraging strategies at High Rise Village (48FR5891), an alpine residential site in Wyoming's Wind River Range occupied between 2800-250 cal B.P. The test was applied to occupations dating to the Medieval Warm Period (1150-550 cal B.P.) and the Little Ice Age (550-100 cal B.P.). Using regional characterizations of temporal variability for these climate periods, a z-score model was employed to develop predictions of how foragers coped with resource variability and predictability during both periods. The model predicted foraging decisions at High Rise Village that managed the risk of caloric shortfall during the slow-changing Medieval Warm Period and the highly variable Little Ice Age. Predictions for each period were tested against corresponding archaeological expectations for subsistence remains, mobility and technology requirements, and the frequency of site use. Further, this study employed a dendroclimatological study to locally characterize the climate periods and test model assumptions of their contrasting patterns of variability. The dendroclimatological study corroborates model assumptions and finds that the Medieval Warm Period was a period of multidecadal climatic variability and resource predictability while the Little Ice Age was characterized by short-term variability and resource unpredictability. Poor preservation of subsistence remains hampered the archaeological study. However, as expected, lithic and chronometric data indicate the site was used residentially and relatively frequently during the Medieval Warm Period, and that use decreased during the Little Ice Age. Medieval use of the site appears to be by Uinta Phase (1800-900 cal B.P.) foragers from the adjacent lowlands, and likely related to regional population pressure, as well as resource accessibility and predictability at High Rise Village. A dramatic decrease in site use predates the Little Ice Age and is likely related to regional population decrease and not LIA conditions at High Rise Village.
879

Utilization of Forage Plants and Diet of Sheep on Utah Winter Range

Green, Lisle R. 01 May 1948 (has links)
Although there is an abudance of material available concering forage consumption by livestock on pasture land and in the feed lot, there is relatively little known about the grazing habits and forage preferences of livestock under range conditions. There has been still less scientific effort expended toward solving the riddle of the grazing animal's diet under winter range conditions. Investigators have suggested means to determine the quantity of forage available on range areas, the carrying capacities of range lands, and methods of determining the degree to which forage has been utilized. The diet of the foraging animal is affected by the quantity of forage availalbe, and the capacity of range lands to support grazing and the degree to which various species are utilized are directly dependent upon the diet, yet virtually nothing is known about the actual compositions of this diet as selected by the animal on the range. There is need for additional scientific information concerning choice of species by the foraging animal and the factors which affect this selection. Basic information of this nature must be known before scientific range management can be applied. Sheep are known to prefer certain plants, and likewise certain portions of these plants. In addition weather, stage of maturity, intensity of use, and plant associations all affect the sheep's diet, and make interpretations and calculations still more complex. This study was designed to determine on the winter range the quantity of forage available to grazing animals, thes species composition of the animal's diet, and to evaluate, where possible, factors affecting the diet.
880

Factors Affecting the Translocation of Herbicides in Mesquite (Prosopis Juliflora)

Young, Dale W. 01 May 1950 (has links)
The control of mesquite is a major range problem in the Southwest. Mesquite is a thorny, woody shrub or tree that has infested 75 million acres of valuable range and pasture land in this region. It competes with grasses and other valuable plants for sunlight, moisture, and plant food. Mesquite also acts as a serious barrier to the handling of cattle on the range.

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