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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.
451

The Effect of Range Condition Upon the Production, Nutritive Intake and Digestibility of Desert Range Forage in Southwest Utah

Taylor, J. Kent 01 May 1962 (has links)
The 65 million acres of winter range in the Intermountain region furnish forage for about five million sheep and four million cattle each winter for approximately six months. These arid ranges are well suited for winter grazing, and are of paramount importance to the livestock industry. Many of these ranges were fully stocked by 1900 and as livestock continued to increase, many winter ranges were seriously over-grazed (Hutchings and Stewart, 1953). Today many of these ranges remain in a deteriorated condition. Forage production has decreased and desirable plants have been replaced by less desirable species. Little is known about the relative production, palatability, digestibility, and nutrient content of forage plants found on ranges in poor condition compared to ranges in good condition, yet such information is fundamental to good range and livestock management. In order to learn more about the effect of range condition upon the forage intake and nutrient content for sheep a study was conducted on typical winter range in southwestern Utah during the winter grazing seasons of 1957-58.
452

Feeding Protein, Phosphorus and Energy Supplements to Beef Cows on Utah Desert Ranges

Olsen, Robert Hyrum 01 May 1959 (has links)
Many of the beef cattle in the Great Basin area are maintained part or all of the year on rangelands. Most of those going on to desert ranges for only part of the year go on during the late fall, winter, and early spring. It is estimated that 50-60 percent of the 600,000 beef cattle grazing on range lands in Utah graze on the one-fourth million acres of desert or semi-desert sometime during the year.
453

Heat Mitigation in Hot Urban Deserts: Measuring Actualities, Magnitude and Effectiveness

January 2019 (has links)
abstract: Urban-induced heating is a challenge to the livability and health of city dwellers. It is a complex issue that many cities are facing, and a more urgent hazard in hot urban deserts (HUDs) than elsewhere due to already high temperatures and aridity. The challenge compounds in the absence of more localized heat mitigation understanding. In addition, over-reliance on evidence from temperate regions is disconnected from the actualities of extreme bioclimatic dynamics found in HUDs. This dissertation is an integration of a series of studies that inform urban climate relationships specific to HUDs. This three-paper dissertation demonstrates heat mitigation aspirational goals from actualities, depicts local urban thermal drivers in Kuwait, and then tests morphological sensitivity of selected thermal modulation strategies in one neighborhood in Kuwait City. The first paper is based on a systematic literature review where evidence from morphological mitigation strategies in HUDs were critically reviewed, synthesized and integrated. Metrics, measurements, and methods were extracted to examine the applicability of the different strategies, and a content synthesis identified the levels of strategy success. Collective challenges and uncertainties were interpreted to compare aspirational goals from actualities of morphological mitigation strategies. The second paper unpacks the relationship of urban morphological attributes in influencing thermal conditions to assess latent magnitudes of heat amelioration strategies. Mindful of the challenges presented in the first study, a 92-day summer field-measurement campaign captured system dynamics of urban thermal stimuli within sub-diurnal phenomena. A composite data set of sub-hourly air temperature measurements with sub-meter morphological attributes was built, statistically analyzed, and modeled. Morphological mediation effects were found to vary hourly with different patterns under varying weather conditions in non-linear associations. Results suggest mitigation interventions be investigated and later tested on a site- use and time-use basis. The third paper concludes with a simulation-based study to conform on the collective findings of the earlier studies. The microclimate model ENVI-met 4.4, combined with field measurements, was used to simulate the effect of rooftop shade-sails in cooling the near ground thermal environment. Results showed significant cooling effects and thus presented a novel shading approach that challenges orthodox mitigation strategies in HUDs. / Dissertation/Thesis / Doctoral Dissertation Design, Environment and the Arts 2019
454

Food Plant Biogeography of the Sonoran Desert

January 2019 (has links)
abstract: There is an ongoing debate around the extent that anthropogenic processes influence both plant species distribution dynamics and plant biodiversity patterns. Past human food use may leave a strong legacy on not only the extent that food plants are dispersed and fill their potential geographic ranges, but also on food plant species richness in areas that have been densely populated by humans through time. The persistent legacy of plant domestication on contemporary species composition has been suggested to be significant in some regions. However, little is known about the effects that past human food use has had on the biogeography of the Sonoran Desert despite its rich cultural diversity and species richness. I used a combination of ecoinformatics, ethnobotanical, and archaeological data sources to quantitatively assess the impacts of pre-Columbian, and in some cases, more recent, human-mediated dispersal of food plants on the Sonoran Desert landscape. I found that (i) food plants do fill more of their potential geographic ranges than their un-used congeners, and that polyploidy, growth form, and life form are correlated with range filling and past food usage. I also found that (ii) both pre-Columbian and contemporary human population presence are correlated with relative food plant species richness. Thus, both past human food use and contemporary human activities may have influenced the geographic distribution of food plants at regional scales as well as species richness patterns. My research emphasizes that there is an interplay between ecological and anthropogenic processes, and that, therefore, humans must be considered as part of the landscape and included in ecological models. / Dissertation/Thesis / Supplemental Raster Files / Supplemental Spreadsheet Files / Masters Thesis Plant Biology and Conservation 2019
455

Du non-film inexploré aux films à restaurer : l'apport des documents d'archives non-film dans les processus de restauration de films muets / From unexplored non-film to films to restore : the input of non-film archival documents in silent film restoration processes

Arteaga, Loïc 29 September 2016 (has links)
Malgré sa récente remise en lumière, le cinéma muet est toujours menacé de disparition, du fait notamment de la décomposition des supports nitrate avec le temps. On estime que 80 pour cent de la production cinématographique mondiale de 1895 à 1929 serait de nos jours perdue, rendant d’autant plus cruciale la restauration des films muets subsistants. Malheureusement, un siècle après, ces films se présentent souvent dans des versions incomplètes et parfois différentes de celles d’origine. Ce travail de recherche s’inscrit dans ce cadre et démontre plus spécifiquement l’apport fondamental des documents d’archives non-film d’époque dans les processus de restauration de films muets. Ces documents, qui constituent désormais les seules sources attestant de la forme d’origine et complète de ces œuvres, permettent notamment, par comparaison avec les films incomplets, l’identification des versions conservées et la reconstruction des trames narratives. Cette réflexion théorique sur les principes directeurs de la restauration de films [I] est ensuite mise en pratique au travers de notre analyse des éléments de restauration du fonds d’archives non-film de la société de production américaine Triangle Film Corporation (1915-1919) conservés par la Cinémathèque française [II] puis, grâce à l’exploitation de ces éléments, au travers de notre contribution aux restaurations des versions françaises du western The Desert Man (La Cité du désespoir, William S. Hart, 1917) et du drame historique The Despoiler (Châtiment, Reginald Barker, 1915) [III] ; deux films Triangle jusqu’alors considérés comme perdus qui constituent les seuls éléments filmiques localisés à ce jour dans le monde / Despite its recent re-lighting, silent cinema is still threatened by disappearance, notably because of nitrate film decomposition over time. It is estimated that 80 per cent of the world cinema production from 1895 to 1929 is currently lost, which makes silent film restoration even more crucial for those that still exist. Unfortunately, a century later, those films often remain in incomplete versions, sometimes even different from the original ones. This research work falls within this scope and specifically demonstrates the essential input of non-film archival documents of the time in silent film restoration processes. Those documents from now on represent the only sources attesting the original and complete form of those films. They notably allow, by comparing them with the incomplete films, both the identification of the preserved versions and the reconstruction of the narrative spine. This theoretical reflection on film restoration guiding principles [I] is then put into practice first through our examination of the restoration elements of the non-film archive collection of the American production company Triangle Film Corporation (1915-1919) preserved by the Cinémathèque française [II] then, based on the exploitation of these elements, through our contribution to the restorations of the French versions of the western The Desert Man (La Cité du désespoir, William S. Hart, 1917) and the historical drama The Despoiler (Châtiment, Reginald Barker, 1915) [III] ; two Triangle films so far presumed lost that constitute the only film elements located in the world until now.
456

The Contributions of Soil Moisture and Groundwater to Non-Rainfall Water Formation in the Namib Desert

Adhikari, Bishwodeep 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Non-rainfall waters such as fog and dew are considered as important source of water in drylands, and the knowledge of possible sources of its formation is very important to make future predictions. Prior studies have suggested the presence of radiation fog in drylands; however, its formation mechanism still remains unclear. There have been earlier studies on the effects of fog on soil moisture dynamics and groundwater recharge. On the contrary, no research has yet been conducted to understand the contribution of soil moisture and groundwater to fog formation. This study, therefore, for the first time intends to examine such possibility in a fog-dominated dryland ecosystem, the Namib Desert. The study was conducted at three sites representing two different land forms (sand dunes and gravel plains) in the Namib Desert. This thesis is divided into two parts: the first part examines evidences of fog formation through water vapor movement using field observations, and the second part simulates water vapor transport using HYDRUS-1D model. In the first part of the study, soil moisture, soil temperature and air temperature data were analyzed, and the relationships between these variables were taken as one of the key indicators for the linkage between soil water and fog formation. The analysis showed that increase in soil moisture generally corresponds to similar increase in air or soil temperature near the soil surface, which implied that variation in soil moisture might be the result of water vapor movement (evaporated soil moisture or groundwater) from lower depths to the soil surface. In the second part of the study, surface fluxes of water vapor were simulated using the HYDRUS-1D model to explore whether the available surface flux was sufficient to support fog formation. The actual surface flux and cumulative evaporation obtained from the model showed positive surface fluxes of water vapor. Based on the field observations and the HYDRUS-1D model results, it can be concluded that water vapor from soil layers and groundwater is transported through the vadose zone to the surface and this water vapor likely contributes to the formation of non-rainfall waters in fog-dominated drylands, like the Namib Desert.
457

Kozo Miyoshi: An Interpretation of Water Through Photography

Hujar, Brittany A. 22 August 2019 (has links)
No description available.
458

Cooling Oasis

Rizvani, Lejla January 2021 (has links)
The urban heat island, UHI, is a phenomenon that occurs in all cities. This phenomenon is an effect of us humans and the environments we have built. What happens in cities are that they re-emit the suns heat and other energies trapping them in this heat island.  The re-emitting happens through the pavement of the city, lack of greenery, roads and how the city is built and its geometry. Cities with skycrapers and of high density see a greater impact of the urban heat island where the wind flow is reduced and more heat is trapped and stored. The UHI is worst experienced in places with a very hot climate, such as the arid desert climate with extreme temperatures year round, like in the UAE and Dubai.  It is vital to tackle the UHI effect problem, because it puts people at danger. Many lives are shed each year due to heat strokes, that can be reduced if we take this problem into consideration when we design our cities. The UHI effect can be reduced by simple yet effective steps.
459

Using multiple lines of evidence to uncover hidden biodiversity in desert spring ecosystems

Walters, Ashley Daniell 31 July 2018 (has links)
No description available.
460

Technology to Address Food Deserts: Hybrid Application of Combined Heat And Power Assisted by Solar Dehumidification for Corner Store Groceries

Almehmadi, Fahad January 2020 (has links)
No description available.

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