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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.
41

Carrying Capacity of the Key Browse Species for Moose on the North Slopes of the Uinta Mountains, Utah

Wilson, David E. 01 May 1971 (has links)
The Shiras moose, Alces alces shirasi, and its winter habitat on the north slopes of the Uinta Mountains in Utah were studied from August, 1969, to July, 1971 to determine the food requirement for moose, the key browse species during the winter months, the acreage, density and utilization of the key browse species, and their carrying capacity for moose. It was determined that an average adult moose had a daily food requirement of 19,133 kilocalories. The key browse species for moose were Salix drummondiana and S. geyeriana. These two species accounted for 92.0 and 4.7 percent respectively of all feeding occurrences on browse species recorded. According to density analyses, S. drummondiana made up 59 percent of the vegetation and S. geyeriana 31 percent. The caloric capacity of the key browse species for moose body maintenance was slightly more than 1.5 billion kilocalories. The moose carrying capacity of the key browse species on the winter range was 80,030 moose days or 445 adult animals for a period of six months. Specifically, the carrying capacity, based on a weighted caloric requirement and annual classification counts, would be 115 bulls, 250 cows, and 156 calves for a period of six months on the winter range.
42

Cartographie détaillée et étude structurale de la région de Moose Mountain, Foothills du Sud-Ouest de l'Alberta

Marcil, Jean-Sébastien 29 May 2019 (has links)
La région de Moose Mountain, située dans la cordillère canadienne au sud de l’Alberta à 50 km à l’ouest de Calgary, est étudiée depuis plusieurs années par les compagnies pétrolières et gazières. Deux champs d’hydrocarbures contenus dans la formation carbonifère de Turner Valley sont exploités dans la région. Les réservoirs se retrouvent dans des écailles de chevauchement, des plis de propagation et des plis de décollement. Le cœur de la structure étudiée, l'anticlinal de Moose Mountain est interprété comme étant un pli de décollement (Newson et Sanderson, 2000). Ce travail de recherche est l'un des seuls à faire l’étude d'un type de piège affleurant en surface. Les travaux de terrain ont permis de réaliser une carte géologique en trois dimensions ainsi que huit nouvelles coupes structurales. Ces coupes ont ensuite servi pour l’élaboration d'un modèle structural 3D de la zone (Massé, 2003), qui a permis de mieux comprendre la géologie, la géométrie et l’évolution cinématique de la région en plus de permettre de valider les travaux de cartographie. La cartographie et l'analyse structurale de la région ont révélé que les rétrochevauchements ont joué un rôle majeur dans l'édification de la structure anticlinale de Moose Mountain. Les relations entre les plis, les chevauchements et les rétrochevauchements démontrent qu'ils sont contemporains. La zone de plis et de failles, située au centre de la région, est un bel exemple de réservoir subtil. Les plis secondaires sont des plis de propagation associés au flanc ouest de la zone triangulaire résiduelle de Moose Mountain. Ces anticlinaux sont très fracturés et grandement affectés par les rétrochevauchements associés à une zone triangulaire. La présence de ces nombreux rétrochevauchements affecte également la migration des fluides et la géométrie des réservoirs subtils, principaux pièges de la région. / Québec Université Laval, Bibliothèque 2019
43

An Initial Characterization of Aquatic Invertebrate Community Structure in the Moose River Basin, Ontario / Aquatic Invertebrates of the Moose River Basin

Bouwman, Catrien W. 04 1900 (has links)
The Moose River Basin in northern Ontario is an important large river system, however very little is known about its aquatic invertebrate community. As macro invertebrates are an integral part of river ecosystems, I conducted an initial assessment of the aquatic invertebrate community structure in the Moose River Basin, at both a fine, and a basin-wide, scale. The fine scale study used invertebrate data collected at five reaches within a 30km stretch of the Groundhog River. The examination of the invertebrate community at a basin-wide scale was accomplished using meta-analysis techniques on twenty-two studies conducted on various rivers within the Basin. The effect of the following factors on community structure were examined: i) the use of different sampling devices, ii) water depth, iii) substrate type, iv) sampling in two consecutive years, and v) spatial scale. I found that the use of various sampling devices resulted in significantly different estimates of community structure. This strongly suggests that consistent sampling protocols are necessary to effectively compare results within, and among, studies. The effect of water depth on community structure was inconclusive, as too few samples were collected to overcome the confounding effects of substrate type. Substrate type had a significant effect on community structure, with greater invertebrate richness and diversity found in fine substrate in the Groundhog River study, but with no consistent patterns at the basin-wide scale. Invertebrate richness and diversity did not differ significantly in the Groundhog River between two consecutive years. In both the fine-scale and the basin-wide studies, the distribution of aquatic invertebrates varied among sites within a river reach, and among reaches within a river. To further examine the biological and physical processes affecting community structure at the fine-scale, consistent sampling protocols should be employed, which may also allow basin-wide trends to emerge. / Thesis / Master of Science (MS)
44

Effects of Habitat, Density, and Climate on Moose and Winter Tick Ecology in the northeastern U.S.

Berube, Juliana 25 March 2024 (has links) (PDF)
Over the past several decades, moose (Alces alces) populations in New England have been in decline due to winter tick (Dermacentor albipictus) parasitism. Winter ticks have been known to infest moose, with over 90,000 ticks being recorded on a single moose. These severe infestations, known as epizootics, are associated with high annual calf mortality rates (> 50%) and reductions in annual productivity (adult calving and twinning rates < 60% and 5%, respectively). Given this, it is increasingly important to effectively monitor moose and winter ticks to address consistent population decline of moose due to winter tick epizootics. The objectives of this work were to measure off-host winter tick abundance and associated environmental variables and compare off-host tick abundance in relation to moose abundance. To assess moose and winter tick abundance, I used a combination of camera traps and winter tick sampling. I set an array of 60 cameras across central-western Massachusetts, which contribute data to the Northeast Wildlife Monitoring Network. I used a plot-based sampling strategy that is effective for heterogenous habitat types to sample winter ticks at sites in western and central Massachusetts as well as the White Mountain National Forest and Umbagog National Wildlife Refuge in New Hampshire. The Penobscot Nation developed the tick sampling approach and contributed additional winter tick data from their sovereign trust lands in Maine. I used N-mixture models to generate estimates of tick abundance for each of the three study areas. Results from this study can inform monitoring strategies for ticks, predict epizootic severity, and develop tools to mitigate threats to moose. This is important for managers looking to prevent further declines in moose populations due to winter ticks and tribes seeking to maintain populations for sustenance.
45

Species Chemistry and Electrochemical Separation in Molten Fluoride Salt

Wang, Yafei 11 September 2019 (has links)
Fluoride salt-cooled high-temperature reactor (FHR) is a safer and potentially less expensive alternative to light water reactor due to the low pressure of primary system, passive decay heat cooling system, chemically inert coolant salt, and high-temperature power cycle. However, one challenge presented by this reactor is that fission products may leak into the primary system from its TRISO particle fuel during normal operation. Consequently, the circulating fission products within the primary coolant would be a potential radioactive source. On the other hand, the containment material of the molten salt such as nickel-based alloys may be corroded, and its species may stay in the salt. Thus, the installment of the primary coolant clean-up system and the study on the contaminant species' chemistry and separation are necessarily needed. Electrochemical separation technique has been proposed as the online coolant clean-up method for FHR for removing some impurities from the salt such as lanthanides and corrosion products. The present research focuses on the electrochemical separations of fission products and corrosion products in molten FLiNaK salt (46.5LiF-11.5NaF-42KF mol%) which is the surrogate of the primary coolant candidate FLiBe (67LiF-33BeF2, mol%) for FHR. The main objective is to investigate the electrochemical behaviors of fission products and corrosion products in molten FLiNaK salt to achieve its separations, and provide fundamental properties to instruct the conditions needed to be applied for a desired electrochemical separation. La and Ce are two main elements concerned in this study since they are major lanthanide fission products. Electrochemical behavior of LaF3 in molten FLiNaK salt was studied on both W and Mo inert working electrodes. Although the standard reduction potential of La (III) is more cathodic than that of the primary salt melt constituents K (I) and Na (I), the electrochemical separation of La from molten FLiNaK salt was achieved by merely using inert working electrode because of the formed LaF63- when KF or NaF exists as the salt constituents. Fundamental properties of La in molten FLiNaK salt were also studied at various situations by electroanalytical methods including cyclic voltammetry (CV), chronopotentiometry (CP), and potentiodynamic polarization scan (PS). Ce is another fission product to be separated out from molten FLiNaK salt. Both inert (W) and reactive working electrodes (Cu and Ni) were utilized to realize the extraction of Ce. The electrochemical behaviors of Ce observed on inert W electrode are similar to the ones obtained in FLiNaK-LaF3 system. Reactive electrodes Cu and Ni were used to precede the electrochemical deposition potential of Ce by forming intermetallic compounds. It turned out only Ni electrode was feasible for preceding the deposition potential and the intermetallic compound was identified as CeNi5. The dissolution of chromium metal in the form of chromium fluoride into molten FLiNaK salt is the main concern of alloy corrosion in FHR. To understand the alloy corrosion and removal of the corrosion products from the FHR salt coolant, the electrochemical behavior and fundamental properties of Cr in molten FLiNaK salt were investigated in the present study as well. A new analysis method for the Cr two-step electrochemical reaction in the salt was developed. The method can be applied to other two-step reactions as well. Liquid bismuth was proposed to be the extraction media for liquid/liquid multistage separation of fission products in molten salt reactor. It also can be used as the cathode to extract the fission product of which the electrodeposition potential is close to or more negative than that of the main constituents of molten salt. Activity and activity coefficient are essential factors for assessing the extraction behavior and viability of bismuth in separating fission products. Hence, in the present study, the activity and activity coefficient of fission products and alkali metals (Li and K) at different concentrations and temperatures were determined by experiment and simulation methods respectively. To conduct the parametric study for the electrochemical reaction process and predict fundamental properties, an electrochemical model including single-step reversible, irreversible, and quasi-reversible reactions, multiple-reaction, and two-step consecutive charge transfer reaction was developed based on MOOSE. Although the model was not applied to analyze the experimental data in the present study, this model provides an efficient and easy way to understand the effect of various parameters on electrochemical reaction process. The present study supplied a comprehensive study on the electrochemical separation of fission products and corrosion products in molten FLiNaK salt and will contribute greatly to the development of FHR. / Doctor of Philosophy / There is a significant increased demand for the generation of electricity with the fast development of modern society and economy. For well over 100 years, the dominant energy sources for producing electricity in the industrialized world are fossil fuels, notably coal, oil, and natural gas. The generation of electricity from fossil fuels is a major and growing contributor to the emission of greenhouse gases that contribute significantly to global warming. As clean and efficient energy, the nuclear power source has been an attractive alternative to traditional fossil fuels. The fluoride salt cooled high temperature reactor (FHR) is a promising Generation-IV advanced nuclear reactor. FHR is a salt-cooled reactor in which the core contains a solid fuel and liquid salt coolant. It combines attractive attributes from previously developed reactors and has the advantages of, for example, low-pressure operation, high temperature power cycle, and passive decay heat rejection. However, the primary salt coolant can unavoidably acquire fission products from the fuel particles and corrosion products from structural material corrosion. Therefore, it is necessary to have a primary coolant clean-up system installed in the FHR to mitigate the contamination and ensure the continued operation of the reactor. Electrochemical separation technique has been proposed as the online coolant clean-up method for FHR. Electrochemical separation can be typically done in a three-electrode cell system (working, counter, and reference electrodes). Through applying a proper electrical potential or a current, the target metal ions in the molten salt will be deposited on the working electrode. In that way, the contaminants, including fission products and corrosion products, can be taken out with a working electrode from the molten salt coolant. In this study, the fundamental behaviors of separation of La, Ce (represent lanthanide fission products) and Cr (represents corrosion products) in FLINAK were investigated. To achieve their separations, the present dissertation provided a comprehensive study about the electrochemical behaviors of La, Ce, and Cr species in molten FLiNaK salt at various situations, and relevant fundamental properties for guiding the conditions needed to be applied for the desired electrochemical separation. Considering the use of liquid bismuth as the extraction media for liquid/liquid separation and the electrode for electrochemical separation of fission products the fundamental properties of fission products and alkali metals in liquid bismuth are also determined in the present study to evaluate the separation behavior and viability. Finally, an electrochemical model for understanding the electrochemical process in the FHR salt coolant clean-up was developed. Overall, the work performed in this study will contribute greatly to facilitate the FHR development.
46

Paupérisation anthropologique et développement humain durable : herméneutique du burkindlem pour une éthique chrétienne inculturée de la promotion humaine intégrale en Afrique / Anthropological pauperization and sustainable human development : hermeneutics of the Burkĩndlem for an inculturated Christian ethics of integral human development in Africa

Sama, Mathieu 25 September 2012 (has links)
Depuis 2000, par la Déclaration du Millénaire, les peuples sont invités à opter pour ce qu’il est convenu d’appeler le « développement humain durable », considéré comme un défi du 21ème siècle. Plusieurs années après, en matière de développement en Afrique, les résultats obtenus restent très en deçà des aspirations. Il s’impose alors une réflexion sur les facteurs qui conditionnent le succès d’un effort pour le « développement humain durable » en terre africaine. Notre hypothèse est que, le « burkĩndlem » moaaga, informé des exigences de l’éthique chrétienne, peut devenir le lieu d’une herméneutique pour un développement humain efficient. Dans la perspective chrétienne, le fondement anthropologique à la base du développement humain durable se trouve dans le concept d’« imago Dei » attribué à l’homme dans la Révélation biblique. Informer le burkĩndlem moaaga de l’enseignement de la Révélation chrétienne au sujet de l’homme considéré comme« image de Dieu », tel est l’objectif de notre démarche. / In 2000, through the Millennium Declaration, peoples are invited to opt for what is called the "sustainable human development". Several years later, in matter of development in Africa, the results are far below expectations. Then, it is necessary to lead reflection on the factors that influence the success of an effort to a "sustainable human development" on African soil. Therefore, our hypothesis is that whenever the Moaaga "burkĩndlem" is informed of the requirements of Christian ethics, it can become the place of a hermeneutics for efficient human development. In the Christian perspective, the anthropological foundation at the base of sustainable human development is the concept of "imago Dei" attributed to man in the biblical Revelation. In this regard, the Christian burkĩndlem appears as highly significant in the African context and is more than suggestive. The objective will be, for the burkĩmba Christians, to attain their full capacity as human beings in order to be open to the salvation that Christ, Son of God and fully man, has brought by grace.
47

Labanoro regioninio parko briedžiai ir jų žiemos ganyklų būklės įvertinimas / Moose of Labanoras Regional Park and estimation of the condition of their winter pasture

Kasperavičiūtė, Jurgita 16 August 2007 (has links)
Magistro darbe tiriamos briedžių žiemos ganyklos Labanoro regioniniame parke. Darbo objektas – Labanoro regioninis parkas- Labanoro girininkija. Darbo tikslas – nustatyti briedžių gausą ir jų žiemos ganyklų būklę Labanoro regioniniame parke. Darbo metodai – R. McCain metodas, statistinė analizė. Darbo rezultatai. Šio darbo tikslas – nustatyti briedžių gausą ir jų žiemos ganyklų būklę Labanoro regioniniame parke. . Tyrimas pasirinktuose bareliuose buvo atliktas R. McCaino metodu, tiriant briedžių ganyklų būklę nevegetaciniu laikotarpiu. Tyrimo juostos ilgis - 14,1 km Briedžių žiemos ganyklų įvertinimas parodė, kad žvėrių poveikis ganykloms priklauso nuo medelių ir ūglių apsaugojimo repelentais. Pažeidimų lygis ganyklose priklausė ir nuo repelentų kokybės, ir nuo augalų apdorojimo repelentais tvarkingumo. Buvo patvirtinta darbo hipotezė, kad nuo repelentų kokybės ir augalų apdorojimo kokybės priklausė kokius augalus briedžiai dažniau rinkosi. Pušies želdiniai buvo žalojami mažiau nei vidutiniškai. / Master‘s Research was based on the assessment of the moose influence in the winter habitats of the Labanoras Regional Park. The object – Labanoras Regional Park. The goal – assessment of the state of winter habitats of moose in Labanoras Regional Park. The research method – R. McCain method and statistics analysis. The goal of this work was to assess of the state of winter habitats of moose in Labanoras Regional Park. I have used R. McCain method assessing the number of moose local population. The method of sample plots was used to assess the state of the wither habitats of moose. The total length of transect is 14,1 km. Research of the state of winter habitats has shown that the moose influence depends on repellent use. The main reason of the strong influence on pine depends not only on repellents use but also on repellent quality. Moose prefer different species of trees including pine. Research has approved this hypothesis. The pine was consumed averagely.
48

A Comparative Analysis Of The Moose Rumen Microbiota And The Pursuit Of Improving Fibrolytic Systems.

Pellegrini, Suzanne Ishaq 01 January 2015 (has links)
The goal of the work presented herein was to further our understanding of the rumen microbiota and microbiome of wild moose, and to use that understanding to improve other processes. The moose has adapted to eating a diet of woody browse, which is very high in fiber, but low in digestibility due to the complexity of the plant polysaccharides, and the presence of tannins, lignin, and other plant-secondary compounds. Therefore, it was hypothesized that the moose would host novel microorganisms that would be capable of a wide variety of enzymatic functions, such as improved fiber breakdown, metabolism of digestibility-reducing or toxic plant compounds, or production of functional metabolites, such as volatile fatty acids, biogenic amines, etc. The first aim, naturally, was to identify the microorganisms present in the rumen of moose, in this case, the bacteria, archaea, and protozoa. This was done using a variety of high-throughput techniques focusing on the SSU rRNA gene (see CHAPTERS 2-5). The second aim was to culture bacteria from the rumen of the moose in order to study their biochemical capabilities (see CHAPTERS 6-7). The final aim was to apply those cultured bacterial isolates to improve other systems. Specifically, bacteria from the rumen of the moose was introduced to young lambs in order to colonize the digestive tract, speed the pace of rumen development, and improve dietary efficiency (see CHAPTER 8).
49

Analyzing the Trends and Spatial Patterns of Moose Vehicle Collisions in Västernorrland County

Tzimos, Alexandros Theodoros January 2020 (has links)
No description available.
50

Vad styr älgars betesmönster? : Hur älgbetesskador på tall påverkas av tallungskogars rumsliga fördelning och areal / Browsing damage by moose in relation to stand size and degree of stand isolation

Berglund, Mattias January 2019 (has links)
One of the largest challenges humanity faces today is reducing CO₂-emissions to mitigate climate change. Part of the solution might be to increase the use of wood products. To do this, the efficiency of forestry has to be improved. In Sweden, a large obstacle for improving the efficiency of forestry is moose, or rather the damages its browsing causes on Scots pine. The aim of this study was to investigate how stand size and stand isolation affects the intensity of moose browsing damage on Scots pine. In addition, effects from tree density, stand age, and interactions between the different factors were investigated. This was done by using data from forest companies and field data collected from 29 Scots pine stands in central Sweden. The data were analysed in a multiple regression analysis, selecting the model that best explained variation in browsing damage. Results show that browsing damage was lower in more isolated stands. Stand size, however, did not have an effect on browsing damage. The factors stand age and Scots pine density had positive effects on the amount of browsing damage, but effects from stand age decreased with increasing pine density. In total, 77% of the variance in browsing damage was explained by the best model. In order to decrease browsing damage on Scots pine, I suggest that land owners take coordinated action to avoid creating large areas of young pine stands within the same area.

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