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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.
1

Community Perceptions of Wildfire Risk and Mitigation in Colorado Springs

Caruolo, Cara Danielle 08 1900 (has links)
This research assessed wildfire mitigation and risk perceptions in two neighborhood in Colorado Springs, CO. Semi-structured interviews were used during transect walks with participants. The research compared residents' perspectives to fire personnel's knowledge.
2

Begränsad framkomlighet på kvinnors bekostnad : En fallstudie utförd på Brunkebergstunneln och David Bagares gata / Limited accessibility at the expense of women : A case study conducted on Brunkebergstunneln and David Bagares gata

Urrutia Valdés, Erik January 2019 (has links)
Målet med denna studie har varit att visa utmaningarna som befinner sig i processer föreliggande trygghet, även om förutsättningar i den byggda miljön visar motsatsen. Därtill har målet varit att bidra med en kompletterande synvinkel på de utmaningar som finns med trygghet och otrygghet för kvinnor i den bebyggda miljön eftersom det oftast inte förmedlas hur kvinnor verkligen upplever obehag i det offentliga rummet. Genom att använda transect walking som huvudsaklig metod, och fotografering som kompletterande tillvägagångssätt, har det möjliggjorts en djupgående porträttering av de känslor Brunkebergstunneln och David Bagares gata kan förmedla. Metoderna har visat tydliga underliggande mönster i den bygga miljön och de återspeglar både sociala och fysiska möjliggörande och begränsningar. Resultatet har bekräftat många av de teoretiska utgångspunkterna, exempelvis att det tycks finnas ett samspel mellan det sociala och det fysiska som orsakar trygghet och otrygghet. Det har tillika visats att det finns en underordning hos många av kvinnorna som intervjuades. Däribland finns det några som avviker från detta och här går det att tyda hur de troligtvis grundar sina liv i andra sociala kontexter. Vad som befinner sig i överordningen är emellertid en del av framtida studier.
3

Morphological Variations in Jack Pine (Pinus Banksiana) Along its' Central to Northern Population Ranges

Kellman, Lisa Marie 04 1900 (has links)
<p> The analysis of six jack pine populations along a north-south transect through the MacKenzie River Valley in the Northwest Territories revealed no significant latitudinal trends in cone and seed morphometric measurements. In attempting to determine whether any variations may be environmentally induced, Radial Growth Rates were, 1)compared between sites. and 2), were correlated with morphometric measurements. No significant results were produced. In correlating trait measurements between sites and between one another in order to determine whether migration may be producing trends, again no significant relatlonships were obtained. A comparison of jack pine with the similar species lodgepole pine suggests that if the same factors controlling the migration of lodgepole pine also control jack pine migration, wing loading should be less in more recent populations. However, this study indicates no significant results in this respect. It is suggested, however, that a further sampling south along the latitudinal transect may produce significant results.</p> / Thesis / Candidate in Philosophy
4

Oxygen and Hydrogen Isotope Studies of Metamorphic Rocks in the Wawa-Kapuskasing Crustal Transect, Ontario, Canada

Li, Hong 02 1900 (has links)
<p> Oxygen and hydrogen isotopic distributions have been studied for rocks from a 100 km transect in the central Superior Province of Ontario, Canada. The transect represents progressively deeper terrains of the Michipicoten Greenstone Belt (MGB), the Wawa Gneiss Terrane (WGT), and the Kapuskasing Structural Zone (KSZ), which correspond to an increase of metamorphic grade and are interpreted as an oblique section through approximately 20 km of crustal thickness. The rocks in the terrains range in age from ~2.76 to ~2.60 Ga, with fewer later intrusions.</p> <p> Equivalent lithologic types have similar δ18O range at middle and lower crustal levels (WGT and KSZ). Tonalitic to granodioritic rocks range from 6.4%o to 9.5o/oo; Dioritic and anorthositic rocks range from 5.5o/oo to 7.6o/oo; a majority of the mafic gneisses (group 1) range from 5.7o/oo to 7.1o/oo, while group 2 mafic gneisses range from 8. 1o/oo to 9.5o/oo. δ18O values of the rocks exhibit a remarkable correlation with SiO2 values, similar to that observed in unaltered plutonic rocks of equivalent composition. Paragneisses have significantly higher δ18O values, 9.3o/oo to 12.2o/oo. Low-grade metavolcanic and metasedimentary rocks of the MGB are 18O-enriched compared to their high-grade equivalents in the KSZ and WGT, 7.4o/oo to 13.3o/oo for mafic to felsic metavolcanic rocks and 11.4o/oo to 14.7o/oo for clastic metasediments.</p> <p> Coexisting minerals from high-grade rocks exhibit 18O-fractionation closely consistent with isotopic equilibrium, suggesting that the isotopic system has not been grossly disturbed. Isotopic thermometers give uniform apparent temperatures, about 553°C to 584°C, across the entire transect, which are lower than the inferred metamorphic temperatures in the highest-grade (KSZ) terrane.</p> <p> The lack of distinctive isotopic differences between equivalent rock types in the KSZ and WGT suggests that there is no significant gradient in δ18O with depth in the crust or with metamorphic grade. The majority of mafic gneisses (Group 1) have δ18O values similar to fresh basalts and appear to have been emplaced either as subaerial extrusives, intrusive sills, or, less likely, as submarine extrusives that were hydrothermally altered at high temperatures. The less abundant Group 2 mafic gneisses have δ18O values typical of greenstones that were altered at low temperature by sea-water, and isotopically resemble low-grade rocks in the Michipicoten and Abitibi belts. In general, no major changes in whole-rock isotopic composition appear to have occurred during granulite facies metamorphism, implying limited flux of water or CO2.</p> <p> The continuous linear gradient in δ18O vs SiO2 in the high-grade rocks cannot be due to differentiation of a mafic source magma. A model involving an association between mantle-derived mafic magma and 18O-enriched crustal materials is more consistent with the oxygen isotopic data.</p> <p> Hydrogen isotope composition of hornblende and biotite has been analyzed from selected rocks. Mafic and anorthositic rocks from the KSZ have δD values from -58 to -62o/oo, suggesting a possible mantle-derived origin of fluid in the system. Two mafic gneisses, which are 18O-enriched, show lower δD values, -89 and -101o/oo. The depletion of deuterium is consistent with the model of low temperature alteration with seawater in a submarine environment. Mafic and tonalitic gneisses from the WGT are also depleted in deuterium, -87 to -109o/oo. Since these rocks intruded into relatively higher level of the crust and commonly contain secondary alteration minerals, it is possible that hydrothermal alteration took place at late- or post-metamorphism stage, and the source of the fluid is likely meteoritic water, The amount of water involved in the exchange was restricted, and was not enough to disturb the oxygen isotopic system in the rocks.</p> / Thesis / Master of Science (MSc)
5

Comprehensive Survey of Butterflies at the Sam D. Hamilton Noxubee National Wildlife Refuge

Gesell, Jordan 25 November 2020 (has links)
In collaboration with the Sam D. Hamilton Noxubee National Wildlife Refuge, I collected detailed information on the butterflies (Lepidoptera: Papilionoidea Latreille, 1802) of the refuge. I produced a comprehensive checklist of butterflies and skippers numbering 60 species. In addition, I collected data on flight periods as well as local plant community associations. Butterfly abundance surveys were conducted to assess seasonal habitat use across six site classes. Special emphasis was placed on pine forest at various stages of management for the endangered red-cockaded woodpecker (Picoides borealis). An exploratory analysis of butterfly diversity and abundance was conducted using non-metric multidimensional scaling (NMDS). Using a Pearson correlation, I determined that butterfly species richness correlated positively with understory plant morphospecies richness across site classes. A correlation was not found for data solely collected from the pine sites, suggesting factors other than understory morphospecies richness govern butterfly richness within a site class.
6

Developing An Ecological Sanitation Transect

Kolesinskas, Ian 23 March 2016 (has links)
A sanitation problem exists for people across the globe: basic human waste collection and treatment is inaccessible to much of the world’s population; and the status-quo gray infrastructure system of sanitation is unsustainable and unsuitable for widespread application. A paradigm shift is needed: this thesis makes the case for developing an Ecological Sanitation Transect to bring back the closed loop that connects consumption, waste excretion, sanitation, and food production. The Ecological Sanitation Transect is a synthesis of ecological sanitation, where human excreta is reused, and the urban transect, where development density is conceptualized along a continuum from rural to urban. Current literature related to transects, sanitation, and the links between them is investigated. An analytical overlay of ecological sanitation strategies onto the transect framework with accompanying visualizations is the resulting integration of these ideas. Case studies from across the transect are detailed. A concluding discussion is followed by directions for future research.
7

Avaliação espaço-temporal de processos do balanço de água em um solo com citros / Spatial and temporal evaluation of water balance processes in a soil with citrus

Moreti, Dolorice 25 August 2006 (has links)
O presente trabalho teve por objetivo quantificar e caracterizar a variabilidade espacial e temporal da armazenagem de água no solo, do potencial mátrico, densidade de fluxo e evapotranspiração da água em um Latossolo Vermelho Amarelo Argissólico cultivado com citros. A parcela experimental constitui-se de duas transeções com 20 pontos de observação espaçados de 4,0 m, cada um deles localizado no centro da distância entre duas plantas ao longo da linha. A cultura de citros foi implantada em março de 1991 com espaçamento de 4,0 m entre plantas e 7,0 m entre linhas. Em cada ponto de observação foram instalados a) um tubo de acesso à uma sonda de nêutrons até a profundidade de 1,20 m, para a quantificação da armazenagem da água no solo, e b) três tensiômetros nas profundidades de 1,00 m, 1,10 m e 1,20 m para a quantificação do potencial mátrico e do gradiente de potencial total da água no solo. As medidas foram feitas ao longo de três anos. As medidas dos potenciais mátricos foram realizadas diariamente e as da armazenagem semanalmente. De cada ponto de observação e profundidade de 0,30 m, 0,50 m, 0,70 m, 0,90 m e 1,10 m foram coletadas amostras de solo com estrutura indeformada para a determinação da condutividade hidráulica saturada, da curva de retenção e a densidade do solo. Por meio da geoestatística, verificou-se uma dependência espacial para a armazenagem de água no solo com um alcance de 17,0 m em média e, para a densidade do solo, potencial mátrico e condutividade hidráulica saturada não se verificou estrutura de dependência espacial. A técnica da estabilidade temporal possibilita identificar no campo o ponto ou os pontos que, subestimam, superestimam ou representam a média de uma determinada variável. Pelo coeficiente de correlação de Spearman entre as datas, os valores de armazenagem e de potencial mátrico foram estáveis no tempo; para a armazenagem de água no solo, a correlação foi maior no período de recarga e, para o potencial mátrico, os coeficientes de correlação foram maiores para os períodos de secagem, ou seja, a estabilidade temporal foi maior para o os períodos de secagem. Por meio da diferença relativa foi possível identificar no estudo da estabilidade temporal, os pontos que mais se aproximaram da média que foram: o ponto 29 nos três anos, para a armazenagem de água no solo, pontos 24, 13 e 11 para o potencial mátrico da água no solo nos anos 1, 2 e 3, respectivamente. Por meio do balanço hídrico, verificou-se um consumo da água pela cultura de citros (evapotranspiração real) de 1.340 mm (consumo médio diário de 3,49 mm) e uma perda por drenagem interna que correspondeu a 10 %, em média nos três anos, da precipitação, para o solo e cultura em estudo. / The objective of the present work was to quantify and characterize spatial and temporal variability of water storage, matric potential, water flux density and actual evapotranspiration in an oxisol cropped to citrus. The experimental plot consisted of two transects with 20 observation points in a spacing of four meters. Each observation point was located in the central distance between two plants in the plant line. The citrus crop was installed in March of 1991 in a spacing of 4 x 7 m (four meters among plants in the line and seven meters among lines). In each observation point were installed a) one aluminiun tube to access a neutron probe till the depth of 1.2 m to determine water storage in the 0-1.2 m soil profile and b) three tensiometers at the depths of 1.0, 1.1 and 1.2 m to determine soil matric potential and soil water total potential gradient at the depth of 1.1 m then to calculated soil water flux density at the 1.1 m soil depth by means of Darcy-Buckingham equation. Measurements were made during three years, those of matric potential, dayly, and those of soil water content, weekly. In each observation point, undisturbed soil samples were removed from 0.3, 0.5, 0.7, 0.9 e 1.1 m soil depths to determine saturated soil hydraulic conductivity, soil water retention curve and soil bulk density. By means of geostatistical techniques, spatial dependence for soil water storage was verified with a range of 17 m in average. It was observed time stability for both soil water storage and matric potential that from the Spearman rank coefficients among dates. For the soil water storage, this coefficient showed higher values during the recharge period, that this, time stability for soil water storage was higher during the recharge period. For the matric potential occurred the inverse: time stability was higher during the drying period. By means of the relative difference from the mean, in the time stability study the following points closer were to the mean: point 29 (for the three years) for soil water storage and points 24, 13 and 11 for soil water matric potential for years 1, 2 and 3, respectively. By means of the soil water storage methodology, it was quantified a water consumption (actual evapotranspiration) for the citrus crop of 1,340 mm (daily average value of 3.49 mm) and a water loss by internal drainage that corresponded to 10 % in average, for the three years of experiment.
8

Distribuição espacial do fluxo radiativo em ondas longas na Região Metropolitana de São Paulo / Spatial distribution of radiative flux on long waves in the metropolitan area of Sao Paulo

Machado, Antonio Jaschke 28 August 2009 (has links)
Muitas vezes, é necessária uma melhor compreensão a respeito da distribuição espacial do fluxo radiativo em ondas longas. Este fluxo é em geral representado pelos estudos em climatologia urbana. Alternativamente, é representado como um estudo interdisciplinar. Novos procedimentos são considerados, porque a superfície urbana é composta de uma variedade muito ampla de elementos. Incluindo um conjunto amostral baseado em observações de transetos móveis automáticos através de várias travessias na Região Metropolitana de São Paulo, além de estimativas paramétricas e considerações de análise escalar. Olhando os objetivos da tese, é fornecida uma contribuição ao desenvolvimento metodológico nos trabalhos de campo, em particular aos climatologistas e planejadores urbanos. Os resultados obtidos implementam a discussão a respeito dos ambientes modificados pelo homem. É apresentada a natureza do fenômeno estudado e o método aplicado é focalizado. São analisados os aspectos essenciais que contribuem para a distribuição do fluxo radiativo nos canyons urbanos. Como a expressão do balanço de energia é uma importante ferramenta para a compreensão do clima urbano, estimativas dos fluxos turbulentos também são considerados. / Many times, it is necessary a better comprehension about the spatial distribution of the longwave radiative flux. This flux is represented just as much by the studies on urban climatology. Alternatively, it is represented as an interdisciplinary study. New procedures are considered, because the urban surface is made up of widely varying elements. Including a sampled dataset based on automatic mobile transects observations through several traverses in the Metropolitan Area of São Paulo, besides parametric estimates and scalar analysis considerations. Regarding the thesis objectives, it is given a contribution to the method development in the fieldworks, in particular to the urban climatologists and urban planners. The obtained results improve the discussion on the manmodified environments. It is explained the nature of the studied phenomena and the applied method it is focused. It is analyzed the essential aspects that contibute to the radiative flux distribution in the urban canyons. As the energy balance expresion is an important framework to the comprehension of the urban climate, estimates of the turbulent fluxes are also considered.
9

Análise do gradiente da temperatura e umidade absoluta no entorno da Represa do Lobo / Analysis of the gradient of temperature and absolute humidity in the vicinity of the Lobo Reservoir

Figueiredo, Mário Augusto Guerzoni 19 August 2013 (has links)
A avaliação da interação reservatórios-atmosfera mostra-se limitada a estudos de grandes reservatórios, que visam analisar eventuais alterações na temperatura e umidade; identifica-se, portanto, a necessidade de estender estudos desta natureza a reservatórios menores. Neste contexto, a presente pesquisa buscou avaliar, por meio de um transecto, o gradiente da temperatura e umidade absoluta na margem da Represa do Lobo, localizada em Itirapina-SP, de modo a determinar se a existência da represa altera os valores medidos na estação meteorológica do Centro de Recursos Hídricos e Ecologia Aplicada CRHEA, instalado nas proximidades. O transecto foi montado na área do CRHEA; ao longo dele, foram instalados sensores termopares tipo T para o registro das temperaturas de bulbo seco (Tbs) e bulbo úmido (Tbu), além de quatro dataloggers, para o armazenamento dos dados. A campanha de coleta foi realizada entre os meses de junho e setembro, período com o menor índice pluviométrico no ano, de modo a evitar alterações nos valores da umidade absoluta; os dados. No estudo, foi empregado o conceito de dias típicos experimentais, por apresentarem características semelhantes aos das Normais Climatológicas para a região e época do ano. Os dados foram analisados por meio do teste estatístico de Mann Whitney e gráficos Boxplot. A comparação estatística entre os psicrômetros revelou que a temperatura se manteve constante, com exceção de um gradiente de 1,5°C a 2°C verificado no 3° quartil dos Boxplot entre a Tbs1 e Tbs3. O mesmo ocorreu com a umidade absoluta, que apresentou variação de apenas 0,5 g/m³ entre dois dos psicrômetros. Conclui-se, portanto, que a metodologia utilizada não apontou evidências de que a presença da Represa do Lobo altere os valores da temperatura e umidade absoluta medidos na estação climatológica do CRHEA. Como recomendação para estudos posteriores cita-se a análise das movimentações das massas de ar, mais especificamente das plumas de umidade. / The assessment of the reservoir-atmosphere interaction seems to be limited to case studies of big reservoirs, that seek to analyze occasional alterations on temperature and humidity; one identifies, therefore, the need of extending such studies to smaller water bodies. The goal of this research is to evaluate, by means of a transect, the temperature gradient and absolute humidity at the Represa do Lobo, located between the cities of Itirapina and São Carlos, SP, in order to determine whether the presence of the reservoir exerts influence on the measurements performed at the meteorological station of the Center for Water Resources and Applied Ecology-CRHEA, installed nearby. The transect was installed in the CRHEA area. T-type thermocouple sensors were placed along its length, in order to record dry bulb (Tbs) and wet bulb (Tbu) temperatures; these data were stored in dataloggers. Data collection was conducted between June and September, period with the lowest rainfall in the year, so as to avoid changes in the values of absolute humidity. For data analysis, the concept of typical experimental days was used, because they have similar characteristics to the Normal Climatological for the region and time of the year. Data evaluation was performed using the Mann-Whitney test statistic and Boxplot graphs. The statistical comparison between psychrometers showed that temperature kept constant, except for a temperature gradient of 1.5°C to 2°C in the 3rd quartile of the Boxplot between Tbs1 and Tbs3. The same behavior was observed for absolute humidity: only a slight variation of 0.5 g/m³ was perceived between two psychrometers. It is therefore concluded that the adopted methodology did not point out evidence that the Represa do Lobo alters the values of temperature and absolute humidity measured at the CRHEA meteorological station. Suggestions for future studies include the assessment of air masses, more specifically the humidity plumes.
10

Metolachlor and TCE Plume Characteristics in a Dolostone Aquifer Using a Transect

Plett, James January 2006 (has links)
Much is known about natural attenuation of contaminants in granular aquifers because many contaminant plumes in these aquifers have been intensively monitored with detailed sampling along cross sections positioned across the plumes (i. e. transects). However, little is known about natural attenuation of contaminant plumes in fractured rock. In this thesis study, strong natural attenuation of a persistent co-mingled plume of trichloroethylene (TCE) and an herbicide (metolachlor) in a 100 <em>m</em> thick dolostone aquifer used for municipal water supply in Cambridge, Ontario is shown based on detailed delineation of groundwater contaminant concentrations along a single transect located 150 <em>m</em> downgradient from the area where the metolachlor entered the dolostone and 300 <em>m</em> downgradient from the TCE source area. This delineation was accomplished using depth-discrete, multilevel groundwater monitoring systems in five cored holes and detailed analyses of contaminant concentration in rock cores. The maximum metolachlor concentration on the transect is a factor of 20 below the maximum concentration in the metolachlor source area and the maximum TCE concentration on the transect is lower by a factor of 100 from the TCE source area. <br /><br /> Matrix diffusion and strong temporal variability of the groundwater flow system caused by pumping of nearby municipal wells have likely caused strong natural attenuation of metolachlor and TCE and degradation has likely contributed to even stronger TCE attenuation. The transect shows rock core concentrations much higher than the groundwater concentrations in the multilevel systems at the same locations and in the conventional monitoring wells, which indicates that plume persistence is likely maintained by back diffusion from the rock matrix, which has very low hydraulic conductivity but substantial porosity, into the active groundwater flow in the fractures. <br /><br /> Metolachlor has been observed at very low concentrations and has persisted at these concentrations in the nearest municipal pumping well located approximately 780 <em>m</em> downgradient of the transect, however this well shows no detectable TCE. The relatively low concentrations along the transect and the replenishment of the plume by back diffusion suggests that a substantial increase of metolachlor or TCE in the municipal well is unlikely.

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