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Ratigan, Ashley. "Paleoenvironmental analysis of Cretaceous mudstones at Slope Mountain, Alaska using carbon stable isotopes." Oberlin College Honors Theses / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1463567305.
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Miller, Andrew J. "Human-Induced Geomorphology?: Modeling Slope Failure in Dominical, Costa Rica Using Landsat Imagery." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1274194885.
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Sinitski, Emily H. "Transtibial Amputee and Able-bodied Walking Strategies for Maintaining Stable Gait in a Multi-terrain Virtual Environment." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31515.
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The CAREN-Extended system is a fully immersive virtual environment (VE) that can provide stability-challenging scenarios in a safe, controlled manner. Understanding gait biomechanics when stability is challenged is required when developing quantifiable metrics for rehabilitation assessment.
The first objective of this thesis was to examine the VE’s technical aspects to ensure data validity and to design a stability-challenging VE scenario. The second and third objectives examined walking speed changes and kinematic strategies when stability was challenged for able-bodied and unilateral transtibial amputees.
The results from this thesis demonstrated: 1) understanding VE operating characteristics are important to ensure data validity and to effectively design virtual scenarios; 2) self-paced treadmill mode for VEs with multiple movement scenarios may elicit more natural gait; 3) gait variability and trunk motion measures are useful when quantitatively assessing stability performance for people with transtibial amputations.
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Pierret, Benoît. "Le fauteuil roulant chez le blessé médullaire, facteur déterminant de l'insertion sociale. État des lieux et effets de la locomotion en dévers sur les astreintes physiologiques." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0216/document.
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Introduction. Les capacités et les possibilités de déplacement en fauteuil roulant manuel (FRM) sont déterminantes pour l'intégration sociale et professionnelle des usagers. Objectifs. Approfondir la connaissance des contraintes de déplacement en FRM à travers 2 études. La 1ère pour identifier les habitudes et préciser les difficultés des usagers ; la 2nde, induite par les résultats de la 1ère, pour évaluer les effets du dévers, encore méconnus, sur les astreintes cardiaques, énergétiques, musculaires et subjectives. Méthodes. La 1ère étude a été menée par questionnaire complété par 118 sujets paraplégiques en FRM. La 2nde étude, en laboratoire avec 25 hommes paraplégiques, comporte 2 tests : un test d?effort sur ergocycle à bras et un test de propulsion de 300 m et 8 conditions combinant 4 dévers (0, 2, 8 et 12 %) et 2 vitesses (0,97 m.s-1 et une vitesse choisie "de confort"). Résultats. La 1ère étude révèle un environnement peu adapté, avec des moyens de transport et des bâtiments souvent inaccessibles sans aide, et des gènes limitant les sorties des usagers parmi lesquelles figure le dévers. La 2nde étude indique des astreintes cardiaques, énergétiques et musculaires significativement modifiées par le dévers et par la vitesse (p < 0,01). L'astreinte subjective n'est pas modifiée par la vitesse. Des différences entre 0 et 2 % sont faibles mais existent. Un dévers de 12 % est difficilement réalisable. Les équilibres des activités musculaires changent dès 2 % de dévers. Le niveau lésionnel modifie de façon très importante les stratégies de déplacements et les niveaux d'astreintes mesurées ou perçues. Discussion-Conclusion. Les effets du dévers sont perceptibles dès 2 % et sont nets et délétères à 8 %. Ce travail permet de proposer de façon plus argumentée un modèle d'astreintes qui conforte le seuil de dévers fixé réglementairement à 2 % permettant à la grande majorité des usagers de FRM de se déplacer de façon autonome et de rester actifsIntroduction. Displacement capacities and possibilities in manual wheelchair (MWC) are strong determinants of social and occupational integration of MWC users. Objectives. Improve the knowledge of the strains involved by displacement in MWC through 2 studies; the first one to identify habits and difficulties of MWC users. The second one, induced by the results of the first one, has assessed the poorly known cardiac, energetic, muscular and subjective strains of the displacement of MWC users on a cross slope. Methods. The first study was a survey answered by 118 paraplegics habitual MWC users. The second one, a laboratory study conducted with 25 paraplegic men, includes 2 tests: a sub maximal arm-cranking test and a 300 m propulsion test with 8 conditions combining 4 cross slopes (0, 2, 8 et 12%) and 2 velocities (0,97 m.s-1 and a "comfortable" chosen one). Results. The first study shows an adverse environment, with many places unreachable without help and disturbances, like cross slope, which hinders users' displacements. The second study demonstrates the increases of cardiac, energetic, muscular and subjective strains with cross slope. Differencies between 0 and 2% cross slopes are low but quantified. Displacement on a 12% cross slope is very difficult. The balance of muscles activities is changing at 2% cross slope. The injury level makes deep changes in the displacements strategies and in as well perceived as measured strain levels. Discussion-Conclusion. Effects of cross slope are perceived for as low as 2% and onwards values. They are high and deleterious at 8%. This work allows to construct a model of cross slope strains which confirms that the regulatory 2% cross slope limit is well chosen because it allows most MWC users to move without help and remain active
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Figueiredo, Augusto Cesar de. "Análise e aplicação da IPA-08 do DNIT visando o controle dos processos de instabilização em taludes de corte rodoviários : o caso da duplicação da rodovia BR-163/364/MT." Universidade Federal de Mato Grosso, 2015. http://ri.ufmt.br/handle/1/237.
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As rodovias constituem importante instrumento para o desenvolvimento do Estado do Mato Grosso, sendo o modal mais utilizado para efetuar a logística de escoamento da produção bem como efetua a interligação entre os municípios. O crescimento do Estado de Mato Grosso acima da média nacional gerou a necessidade de uma grande demanda por infraestrutura, e em especial, por adequações e melhorias no sistema viário. Atualmente, o Governo tenta minimizar esta conjuntura através da execução de várias obras rodoviárias a fim de melhorar a trafegabilidade e consequentemente estruturar a sua logística do transporte. Paralelamente, esta escolha pelo transporte rodoviário acarreta impactos ambientais significativos embora a Engenharia Rodoviária tenha avançado no que diz respeito a tecnologia de construção e o conceito de preservação ambiental. A maioria das obras rodoviárias, durante a sua fase executiva, não possuem um rigor e uma metodologia apropriada para minimizar e controlar os impactos gerados principalmente aos processos ligados à dinâmica superificial e em especial as instabilizações dos taludes provenientes dos cortes. Os Estudos acerca dos EIA/RIMA previstos no Artigo 10 da Lei 6.938/81 da Política Nacional do Meio Ambiente objetivando o Licenciamento Ambiental são extremamente abrangentes e genéricos e não se constituem como ferramenta adequada para o correto monitoramento ambiental dos processos do meio físico durante o processo executivo destas rodovias. Diante desta realidade, este trabalho de pesquisa tem por objetivo subsidiar procedimentos metodológicos com o intuito de analisar e aplicar a Instrução de Proteção Ambiental (IPA-08), a fim de servir de ferramenta técnica para a avaliação dos impactos ambientais nos taludes de corte presentes na rodovia em execução e provocados pelas modificações no meio físico e em particular nos processos da dinâmica superficial, gerados na área de influência direta (AID). Para tanto, adotou-se como área de estudo um segmento pertencente a duplicação da rodovia BR-163/364/MT - Rosário Oeste ao Posto Gil com o intuito de acompanhar e inspecionar os impactos na área delimitada objetivando avaliar o desempenho do trecho rodoviário em estudo. Nesse trabalho foram apresentados como resultados a delimitação da área de estudo, sua compartimentação e caraterização geotécnica, a caraterização e apresentação das instabilizações nos taludes de corte assim como uma análise e proposta de aplicação da IPA-08 como forma de controle preventivo e corretivo.
The highways are an important tool for the development of the State of Mato Grosso, the most widely used modal to make the production flow logistics and makes the interconnection between the municipalities. The growth of the State of Mato Grosso above the national average generated the need for a large demand for infrastructure, and in particular for adjustments and improvements in the road system. Currently, the Government tries to minimize this situation through implementation of various road works to improve the trafficability and consequently structure their transport logistics. In parallel, this choice by road transport entails significant environmental impacts although the Road Engineering has advanced with regard to construction technology and the concept of environmental preservation. Most road works during their execution phase, not of a rigor and an appropriate methodology to minimize and control the impacts generated primarily to surface water resources ephemeral, intermittent and perennial directly influenced by the construction. Studies on the EIA / RIMA provided for in Article 10 of Law 6938/81 of the National Environmental Policy aiming Environmental Licensing are extremely comprehensive and generic and does not constitute as a proper tool for the proper environmental monitoring of surface water resources during executive these highway. Given this reality, this research has the objective to subsidize methodological procedures in order to anlyze and apply the Instruction of Environmental Protection (IPA-08) in order to serveas a technical tool for the evaluation of environmental impacts on cutting slopes present on the road in construction and caused by changes in the physical environment and in particular in the processes of dynamic surface, generated in the area of direct influence (AID). Therefore, it was adopted as the study area belonging to a segment duplication of BR-163/364 / MT - Rosario Oeste Posto Gil for the purpose of monitor and inspect the area bounded on the impacts to evaluate the performance of the road stretch in study. In this work results are presented as the delimitation of the study area, its subdivision and geotechnical characterization, the characterization and presentation of instability in cutting slopes as well as an analysis and proposed application of the IPA-08 as a form of preventive and corrective control.
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Campbell, Elaine. "The sedimentology of lower-slope clastic successions in deep-water environments." Thesis, University of Aberdeen, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440059.
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Interest has been stimulated by discovery of hydrocarbons in turbiditic sandstones interpreted as submarine slope deposits. The aim of this study is to test models of slope development, and to document the variety of gravity flow processes and products within deep-water lower-slope regions. This has involved a comprehensive sedimentological study of the geometry, facies distribution and spatial and temporal variation of internal architectural elements within deep-water clastic successions from three study areas. The Maras Foreland Basin (Miocene) contains an exhumed deep-water slope succession. Two laterally equivalent intervals highlight the complex lateral facies transitions that occur in lower-slope regions. The Macduff Slate Formation (Cambrian/Ordovician) was deposited in a deep-water passive margin environment and contains associated glacial deposits. Following deposition the sediments experienced several phases of regional metamorphism and associated deformation. A detailed structural and sedimentological study of several laterally equivalent intervals determined that the sediments were deposited in a sinuous, aggradational channel system with associated levee-overbank elements. Six age-equivalent cored reservoir intervals, offshore Côte d’Ivoire, West Africa (Cretaceous) were deposited on a submarine slope during late syn-rift extension. A comprehensive sedimentological study complimented by petrophysical and seismic data determined that deposition occurred within a series of stepped mini-basins or tilted fault blocks. There is evidence that the basins did not fill uniformly and that fault activity during sedimentation controlled sediment distribution patterns across faults, intervening transfer zones and within fault blocks. The three study areas differ in age, basin type, grain-size range and the interpreted length and geometry of the shelf-to-slope profile, but contain comparable facies associations linked to depositional architectural elements predicted by models of lower-slope successions.
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Armitage, Dominic Anthony. "High-resolution architectural evolution of depositional elements in deep-marine slope environments : the quaternary Niger delta slope, quaternary southwest grand banks slope, Canada, and Cretaceous Tres pasos formation, Chile /." May be available electronically:, 2009. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Hansson, Lina. "Upper slope sedimentation environments in the Gaoping river-sea system of SW Taiwan." Thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-90906.
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The Gaoping Slope, off the south west coast of Taiwan, is a tectonically active sedimentation environment attaining most of its sediment from the Gaoping River. This study examines sediment cores from two localities at 375 m and 495 m water depth by using X-radiography, Grain size- and 210Pb analysis, with the purpose of comparing the sedimentation environment at the two sites and examine how they were both affected by high sediment delivery during typhoon Morakot.The shallow site has coarse bioturbated sediment, whereas the deeper site had laminated fine sediment containing high amounts of organic material. Both localities display a 13-20 cm thick recently deposited layer in the cores taken after typhoon Morakot. The layers are characterized by coarsening-fining sequences. All cores show cyclicity in the grain size data.We suggest that the shallow station has a more energetic environment, affected by wave reworking, tides, and alongshore currents supplying riverine material from the Gaoping river. The deep site has a calmer sedimentation environment dominated by hemipelagic settling of suspended material. The recent accumulated deposits are most likely hyperpycnites from density driven hyperpycnal flows, originally caused by canyon overflows in the Gaoping- and the Kaohsiung canyon during the typhoon. The strata found at the Gaoping slope is a result of submarine mass transport of sediment, and reflect the interaction between annual seasons and extreme events triggered by typhoons and earthquakes - eroding, transporting, and depositing sediment in the area.
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CARVALHO, CARLOS VITOR DE ALENCAR. "SIMULATION OF TRANSPORT AND DEPOSITION OF SILICICLASTIC SEDIMENTS IN PLATAFORM, SLOPE, AND BASIN ENVIRONMENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3529@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOGRUPO DE TECNOLOGIA DE COMPUTAÇÃO GRÁFICA - PUC-RIO
A geologia sedimentar trata do estudo dos processos físicos, químicos e biológicos atuantes na superfície da Terra não só no presente como também ao longo de toda a sua evolução. Em função disso, ela pode ser aplicada em diversos campos, como, por exemplo, no estudo da formação de combustíveis fósseis. Um dos focos principais da geologia sedimentar reside em determinar os parâmetros e processos pelos quais as bacias sedimentares são preenchidas. Neste trabalho é apresentado o desenvolvimento de um simulador numérico de sedimentação tridimensional, chamado de STENO, com ênfase nos processos deposicionais em ambientes de plataforma, talude e bacia. O algoritmo do simulador é baseado nos conceitos quantitativos formulados pela Estratigrafia de Seqüências, como mecanismos de controle primário da arquitetura dos estratos sedimentares, e em uma análise numérica para simulação do fluxo bidimensional de um fluido incompressível, em regime permanente, não viscoso, em função da batimetria da região a ser modelada através de um grid regular definido pelo usuário. O campo de velocidades, calculado a partir das velocidades de aporte de sedimentos e das velocidades de corrente, é utilizado para determinar a direção de escoamento dos sedimentos (linhas de correntes). A abordagem dada pelo algoritmo do STENO é inovadora em termos dos algoritmos existentes, pois considera que os sedimentos são transportados hidrodinamicamente, isto é, na direção x e y eles são transportados seguindo as linhas de corrente e na direção z a movimentação/deposição dos sedimentos é controlada pelo ângulo de estabilidade de cada fração litológica (areia, silte ou argila) e pelo volume do espaço disponível para acomodação em cada uma das colunas formadas a partir das células do modelo discretizado.
Sedimentary Geology deals with the study of the physical, chemical and biological processes operating in the surface of the Earth, not only in the present days, but also along all History. Therefore, it can be applied in miscellaneous fields, as, for example, in the study of fossils fuels formation. One of the main focus of sedimentary geology inhabits in determining the parameters and processes for which the sedimentary basins are filled. In this work the development of a numerical simulator of sedimentation 3D, called STENO is presented, with emphasises the depositary processes in platform, slope, and basin environments. The algorithm of the simulator is based on the formulated quantitative concepts for Sequence Stratigraphy, as mechanisms of primary control of the architecture of sedimentary stratus, and in a numerical analysis for simulation of the 2D steady-state flow of a incompressible fluid, not viscous, in function of the bathymetry of the region represented by one regular grid defined by the user. The velocity field calculated from boundary conditions (sediment aport velocity and for field stream velocity) it is used to determine the direction of draining of the sediments (streamlines). The algorithm of STENO is innovative because it considers that the sediments are carried hydrodynamicsly, that is, in direction x and y they are carried following streamlines and in direction z. The movement/deposition of sediments is controlled by an angle of stability of each lithology fraction (sand, silte or clay) and by the volume of the available space for accommodation in each one of the columns formed in the cells of the discretized model.
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Jones, Cullen A. (Cullen Albert). "Engineering properties of Resedimented Ugnu Clay from the Alaskan North Slope." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/60804.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (v. 1, p. 248-256).
This research determined the engineering properties of laboratory Resedimented Ugnu Clay (RUC) specimens created using recovered material from 3800 ft below the surface of the Alaskan Northern Slope to aid with future petroleum exploration. Thirteen constant rate of strain (CRS) tests were performed to ascertain the compression properties as a function of consolidation stress. Consolidation stress for these specimens ranged from 6,800 kPa to 39,000 kPa. CRS results show that the compression ratio (CR) decreases with increasing consolidation stress which is in accord with research completed on resedimented Boston Blue clay (RBBC) and behavior of RUC during Ko consolidation. The CRS data established a value of cv at 0.0015 cm 2/sec and an average Ck of the tested specimens at approximately 0.35. Thirteen K, consolidated triaxial compression tests were performed to ascertain the Ko and undrained shear properties as a function of consolidation stress. Consolidation stress for these specimens ranged from 190 kPa to 9,800 kPa. The range of Ko at maximum stress ranged from 0.47 to 0.65 where increasing consolidation stress resulted in an increase in Ko values and a decrease in undrained shear strength, which is in accord with research completed on resedimented Boston Blue clay (RBBC) and resedimented Gulf of Mexico Clay (RGOM) at MIT. Undrained Strength Ratios (USRs ) ranged from 0.262 to 0.349 with a trend of decreasing normalized strength and strain softening, and increasing axial strain at failure increase with increasing consolidation stress. Peak friction angles during shearing ranged from 20.30 - 27.80 with a general trend of decreasing with increasing consolidation stress. Observed Skempton's A parameters at failure (Af) ranged from 0.407 to 0.777 with a trend of with increasing with consolidation stress. Normalized secant moduli (Eu/o've ) measured at 0.01 % axial strain ranged from 150 to 475 with the trend of decreasing with increasing consolidation stress. When compared with RBBC and RGOM, the effects of plasticity and mineralogy on clay behavior are readily apparent. These results will provide data to perform analysis and design of petroleum exploration strategies and calibrate soil models.
by Cullen A. Jones.
S.M.
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Nagengast, Amy L. "Energy Performance Impacts from Competing Low-slope Roofing Choices and Photovoltaic Technologies." Research Showcase @ CMU, 2013. http://repository.cmu.edu/dissertations/192.
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With such a vast quantity of space, commercial low-slope roofs offer significant potential for sustainable roofing technology deployment. Specifically, building energy performance can be improved by installing rooftop energy technologies such as photovoltaic (PV) panels, and/or including designs such as white or green roofs instead of traditional black. This research aims to inform and support roof decisions through quantified energy performance impacts across roof choices and photovoltaic technologies. The primary dataset for this research was measured over a 16 month period (May 24, 2011 to October 13, 2012) from a large field experiment in Pittsburgh, Pennsylvania on top of a commercial warehouse with white, black and green roof sections, each with portions covered by polycrystalline photovoltaic panels. Results from the Pittsburgh experiment were extended to three different cities (San Diego, CA; Huntsville, AL; and Phoenix, AZ) chosen to represent a wide range of irradiance and temperature values.
First, this research evaluated the difference in electricity production from a green-moss roof and black roof underneath photovoltaic panels to determine if the green roof’s cooler air increases the panel efficiency. Second, separate studies examine 1) average hourly heat flux by month for unobstructed and shaded roof membranes 2) heat flux peak time delay, and 3) air temperature across roof types.
Results of this research show green roofs slightly increased (0.8-1.5%) PV panel efficiency in temperatures approximately at or above 25⁰ C (77⁰F) compared to black roofs. However in cool climates, like Pittsburgh, the roof type under the PV panels had little overall impact on PV performance when considering year round temperatures. Instead, roof decisions should place a stronger emphasis on heat flux impacts. The green roof outperformed both black and white roofs at minimizing total conductive heat flux. These heat flow values were used to develop a new, straight-forward methodology to roughly estimate heat flux impacts of different roof types in other climates using ambient temperature and solar irradiance. While managing heat flow is important for building energy performance, roof choices need to include a systems level analysis encompassing a year for the specific region to best quantify the overall energy impacts
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Mirzoyan, Artak Davit. "Lateral Resistance of Piles at the Crest of Slopes in Sand." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2088.pdf.
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Fritzson, Hanna. "Effect of Environmental Factors on Pore Water Pressure in River Bank Sediments, Sollefteå, Sweden." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-333788.
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Pore water pressure in a silt slope in Sollefteå, Sweden, was measured from 2009-2016. The results from2009-2012 were presented and evaluated in a publication by Westerberg et al. (2014) and this report is an extension of that project.In a silt slope the pore water pressures are generally negative, contributing to the stability of theslope. In this report the pore water pressure variations are analyzed using basic statistics and a connection between the pore water pressure variations, the geology and parameters such as temperature, precipitation and soil moisture are discussed.The soils in the slope at Nipuddsvägen consists of sandy silt, silt, clayey silt and silty clay. The main findings were that at 2, 4 and 6 m depth there are significant increases and decreases in the pore water pressure that can be linked with the changing of the seasons, for example there is a significant increase in the spring when the ground frost melts. As the seasons change, so do the temperature and amount and type of precipitation. Other factors that vary with the season are the amount of net radiation, wind speed and relative humidity, all of which affect the amount of evapotranspiration. At greater depths the pore water pressue is most likely affected by a factor/factors that varies from year to year, possibly the total amount of rainfall. Therefore, the anticipated increase in precipitation in Scandinavia due to climate change could be an important factor influencing slope stability.What precipitation, temperature and evapotranspiration have in common is that they affect the amount of water infiltrating the soil, and thereby the soil moisture content. How the soil moisture is distributed and flows through the soil (sub-surface flow) is governed by the different soil types and their mutual order in the slope, as well as by factors affecting the structure of the soil, e.g. animal burrows and aggregation. The formation of ground frost also affects the way in which the water present in the soil is redistributed.At c. 14 m depth in the slope, there is a saturated layer with positive pore water pressures, which could be one of several such layers. The overall groundwater situation in a silt slope is complex; several different bodies of water can develop, and to get a complete picture of the ground water situation (andthereby also the pore water pressure variations) thorough hydrological surveys are needed.Under 2009-2016 mättes porvattentrycket i en siltslänt i Sollefteå. Resultaten från 2009-2012presenterades och utvärderades i en publikation av Westerberg et al. (2014) och detta examensarbete är en förlängning av det projektet.I en siltslänt är porvattentrycket vanligtvis negativt vilket bidrar till stabiliteten i slänten. I den härrapporten är variationerna av porvattentrycket analyserade med hjälp av enkel statistik och en koppling mellan variationerna och geologin samt parametrar så som temperatur, nederbörd och fukthalt i marken diskuteras.Jordarterna i slänten vid Nipuddsvägen består av sandig silt, silt, lerig silt och siltig lera. Slutsatsen var att på 2, 4 och 6 m djup ökade och minskade porvattentrycket med årstiderna, till exempel ökade porvattentrycket signifikant vid tjällossningen. När årstiderna skiftar ändras även temperaturen och mängden, och typen, av nederbörd. Andra faktorer som varierar över året är netto-instrålningen, vindhastigheten och den relativa fuktigheten och dessa faktorer påverkar i sin tur evapotranspirationen. På större djup beror antagligen portrycksvariationerna på någon eller några faktorer som skiljer sig åt från år till år, möjligtvis den totala mängden nederbörd. Därmed skulle den ökade nederbörd som förväntas i Skandinavien på grund av klimatförändringarna kunna påverka släntstabiliteten.Vad nederbörd, temeperatur och evapotranspiration har gemensamt är att de påverkar mängden vatten som infiltrerar marken, det vill säga de påverkar markens fukthalt. Hur vattnet är födelat i marken beror på de olika jordarterna och deras inbördes ordning i slänten, men också av faktorer som påverkar markens struktur så som aggregation och uppluckring av jorden på grund av marklevande djurs aktivitet. Även formationen av tjäle på vintern har troligtvis en viss inverkan på hur vattnet i marken omfördelas.På 14 m djup finns ett vattenmättat lager med positiva porvattentryck vilket skulle kunna vara ett av flera sådana lager. I en siltslänt är grundvattensituationen mycket komplex, flera magasin av vatten kan bildas. För att få en bra bild av grundvattensituationen (och där med också porvattentrycksvariationerna)behöver noggranna hydrologiska undersökningar genomföras.
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Hobson, Anne Carrie Hickey. "Using remotely-sensed nearshore suspended sediment as an indicator of environmental change on the Alaskan North Slope." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219026.
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Lipasti, Johannes. "Artificial Environments and Spatial Travel Implications: The case of Madrid Snow Zone." Thesis, Umeå universitet, Kulturgeografi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-136266.
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Place has been a fundamental topic for geographers (Agnew, 1987). It stands both for a study object and a manner of perceiving the world. This thesis departs from the theoretical debate regarding places and how places are considered as being spatially fixed in the sense that places cannot be reproduced or imitated elsewhere. However, technological innovations have extraordinary significance in all the realms of leisure and lifestyle (Godbey, 1997) whereas, leisure activities increasingly are being simulated and reproduced exemplifying the new postmodern culture and the ‘post-tourist’ (Urry, 1990). Thus, challenges the spatial fix of places (Shaw & Williams, 2004). There has been little empirical research regarding artificial environments and therefore, the research problem contributes to understand how artificial environments are altering habitual travel patterns regarding the ‘genuine’ or as previous authors have stated, regarding the ‘real thing’. The research questions proposed for the study, directed the researcher to a quantitative approach using the questionnaire as a main source of data collection. The simulated environment that was investigated in the study was the indoor ski slope located in Madrid (Spain). The results showed that the simulated environment is enhancing and intervening the ski activity. For most of the skiers the indoor ski slope is complementing their ski activity in front of the outdoor ski resorts. Furthermore, the facility is recruiting every year a great number of new skiers that after skiing indoors desire to experience the ‘real thing’. Due to the proximity of the facility to the major urban areas, the indoor ski slope is acting as an intervening opportunity and boosting the visitors towards outdoor skiing.
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Borgomano, Jean. "La plate-forme et le talus carbonates du cretace superieur du gargano et des murges (italie meridionale) : stratigraphie, sedimentologie, diagenese, fonctionnement tectono-sedimentaire." Aix-Marseille 1, 1987. http://www.theses.fr/1987AIX11063.
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Ce travail concerne les formations du cretace superieur du massif du gargano et des murges (italie meridionale). L'etude stratigraphique, basee sur la faune de foraminiferes et de rudistes, permet de mettre en evidence plusieurs discontinuites dans la serie et une tendance a l'emersion marquee egalement par la formation de bauxite. Les depots sont caracteristiques de milieux de plateforme carbonatee et de talus. Les breches et depots bioclastiques du talus correspondent a des mises en place par ecoulements ou glissements gravitaires controles par des phenomenes tectoniques en relation avec la structuration de la marge. Les phenomenes diagenetiques sont egalement etudies
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Mithan, Huw. "Quantifying the dynamic response of permafrost and slope stability to a changing climate." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/111329/.
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The Arctic contains a wealth of landforms that are governed by the diurnal and seasonal response of permafrost to climatic and topographic forcings. Of key importance to the process rates of many periglacial landforms is the dynamic behaviour of the active layer, which regulates the transfer of heat and moisture between the atmosphere and permafrost. The strong dependence of periglacial process rates on active layer dynamics makes this geomorphic system particularly sensitive to future increases in Arctic temperatures and precipitation. These increases will continue to degrade permafrost, affecting the distribution and rates of periglacial processes. I develop a landform classification model on Svalbard that reveals solifluction and scree to be the most dominant hillslope processes acting on this landscape, with sediment fluxes greatest in solifluction. A combination of landslide mapping, solifluction modelling and slope stability analysis in Alaska reveals that landslides are coincident with convergent topography on soliflucting hillslopes that have concentrated ground ice at depth. Convergent topography allows for higher moisture availability that feeds the growth, concentration, and development of a large network of ice lenses at the permafrost/active layer boundary. The excess pore pressures generated upon thaw reduces the shear strength of soil at the base of the active layer, causing it to slide downslope along a planar slip surface on top of the unthawed permafrost. Due to a warming Arctic, permafrost is expected to continue thawing, creating an ever more dynamic and deeper active layer. Consequently, the relative regional extent of periglacial landforms in mountainous Arctic environments is expected to change, with Arctic hillslopes becoming more unstable during extreme summer thawing. This will pose a greater hazard to Arctic infrastructure and act as a major force for environmental and geomorphological change.
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Vytiniotis, Antonios. "Contributions to the analysis and mitigation of liquefaction in loose sand slopes." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/70761.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, February 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 319-328).
This research analyzes the vulnerability of loose granular waterfront fills to liquefaction in seismic events and considers the effectiveness of Pre-fabricated Vertical (PV) drain systems in mitigating potential damage. The analyses are based on non-linear finite element simulations of coupled flow and deformation using the OpenSees open-source software framework. The analyses make extensive use of an advanced elasto-plastic model developed by Dafalias and Manzari (2004; DM2004) for simulating the cyclic response of sand. The model formulation is based on theories of bounding surface plasticity and critical state soil mechanics. The thesis presents a series of algorithms needed to achieve robust integration of the DM2004 model in OpenSees, documents model calibration for two test sands (Nevada, Toyoura), and evaluates its predictive capabilities and limitations at the element level. The results show that although the DM2004 model describes quite realistically the accumulation of plastic shear strains in drained and undrained cyclic shearing, the material can shakedown to a stable condition over a large number of load cycles (a condition of alternating plasticity). One-dimensional drain elements have been developed to represent laminar or turbulent discharge through the PV drains based on classic Darcy-Weisbach pipe flow. The elements also allow for fluid storage for cases where the PV drains extend through low permeability clay soils above the water table. The numerical predictions of ground response have been evaluated using results from a well-instrumented centrifuge model test (SSK01) performed by colleagues at the University of California at Davis (Kamai et al., 2008). The model includes a full array of PV drains installed within one of two facing slopes (directed towards a central channel) under a series of harmonically-varying horizontal base acceleration events. The simulations show reasonable predictions of accelerations, pore pressure accumulation and displacements within the untreated loose Nevada sand fill and the effectiveness of the PV drains in reducing permanent deformations within the slope. Numerical simulations of vulnerable piled-wharf structures have been carried out for the reference geometry of an 18m high, partially submerged fill slope (typical of port facilities on the USA West coast). This thesis describes the free-field simulations of ground response for a suite of 58 reference seismic ground motions from the NGA database (Chiou et al., 2008) and from Shakeout simulations (Graves et al., 2008) while a parallel study at the Georgia Institute of Technology (Shafieezadeh, PhD 2011) couples the predicted free-field pore pressures and ground deformations to the response of the piled-wharf structure. The numerical framework for free-field analyses involves special considerations of the boundary conditions to minimize the reflection of energy from far-field lateral boundaries and to represent mechanical and hydraulic interactions at the ocean-soil interface. The analyses use the DM2004 model with input parameters corresponding to Toyoura sand, and include parametric studies to evaluate how the in-situ fill density and hydraulic conductivity affect the ground response for a reference strong motion acceleration record. Numerical simulations have been performed for the suite of 58 reference ground motions for both the untreated (i.e., existing) fill and for the case where full-depth PV drains are installed at locations behind the crest of the slope (i.e., minimally-intrusive mitigation system). The computed permanent slope deformations are not well described by published empirical correlations, but are well correlated with the peak ground accelerations (PGA) and especially the Arias intensity (Ia), while directionality of the ground motions has minimal effects on the ground response. More detailed observations show that average shear strains (i.e., slope damage) are closely linked to the development of excess pore pressures within the slope. The PV drain mitigation system is effective in reducing permanent deformations and achieves an improvement ratio in the range 1.5-3.0 (untreated: PV deformations) that is insensitive to the ground motion characteristics. The damage results have been incorporated in slope fragility curves that can be used by risk analysts to quantify the expected costs from earthquake damage.
by Antonios Vytiniotis.
Ph.D.
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Kirk, Kathleen Jane. "Instability of blanket bog slopes on Cuilcagh Mountain, N.W. Ireland." Thesis, University of Huddersfield, 2001. http://eprints.hud.ac.uk/id/eprint/22330/.
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There are many accounts of slope failures on blanket bogs, but their nature and controls are poorly understood. This study investigates the mechanisms of blanket bog failure on Cuilcagh Mountain, north-west Ireland, and identifies the critical factors affecting the stability of peatland hillslopes. This is achieved by means of extensive field investigations involving hydrological monitoring, soil sampling and comprehensive laboratory analyses to determine the physical, hydrological and geotechnical properties of the blanket peat. The results from these investigations form the basis of hillslope hydrology and slope stability modelling using finite-element modelling programmes (commercial SEEP/W and SLOPE/W software). A total of 47 failures scars were identified on Cuilcagh Mountain involving an estimated 300,000 m3 of peat. Detailed field investigations revealed two main types of peatland slope failure: shallow translational peat slides associated with the failure of clay underlying the blanket peat, and bog flows in which failure occurs as a slurrytype plastic flow with the failure zone located within the peat. Peat slides were more prevalent on the steeper slopes (7.0-17.00) of Cuilcagh, whereas bog flows were found exclusively on low gradient slopes (1.5-7.50) with deep accumulations of peat (typically up to 2.5 m). Previously it had been suggested that bog failures were confined to steep slopes or peripheral areas of blanket bogs. However, on Cuilcagh Mountain they appear to be an integral part of the natural evolution of the main peatland, with the presence of many failure scars at different stages ofre-vegetation and recovery. Conventional methods of slope stability analysis (Factor of Safety using limit equilibrium methods) were found to be adequate for use on peat slide failures, but were not as suitable for analysing the slopes prone to bog flows. Sensitivity analyses indicate that cohesion of the failure material (Le. the catotelm peat for bog flows and the underlying clay for peat slides) is the most critical factor contributing to slope failure. A reduction in cohesion is thought to be related to decomposition andlor progressive failure of the peat, or weathering and creep of the underlying clay. Increased overburden pressure from continuing peat accumulation is also an important factor in reducing the overall stability of a peatland slope. The initiation of bog flows and peat slides can occur from the progressive failure of the material in question, but there is more evidence to suggest that both types of failure are more frequently initiated as a result of a specific trigger event usually associated with high intensity rainfall.
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Papiol, Nieves Vanesa. "Dynamics of benthopelagic food webs of the Catalan slope (NW Mediterranean Sea): environmental drivers and influence on reproductive cycles." Doctoral thesis, Universitat Autònoma de Barcelona, 2013. http://hdl.handle.net/10803/117198.
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L’estacionalitat en diversos aspectes de la fauna batial s’atribueix normalment a canvis estacionals en l’aliment disponible, però existeix escassa informació respecte aquesta connexió en megafauna predadora. La present tesi doctoral consisteix en l’anàlisi de les dinàmiques estacionals de les comunitats de megafauna bentònica i bentopelàgica i en l’estudi de la seva relació amb els fluxos i la disponibilitat d’aliment. La tesi es basa en dades recollides en les quatre estacions d’un any natural en el talús continental mig de la Mar Catalana (Mediterrani NO). Aquest talús és un sistema oligotròfic influenciat per fluxos de matèria orgànica vertical i advectiu amb canvis estacionals marcats. Hem determinat els patrons estacionals en l’estructura i el funcionament de les comunitats profundes de megafauna, essencialment peixos i crustacis decàpodes, i hem explorat les relacions entre els patrons faunístics i els principals processos que proporcionen aliment a profunditats batials, les característiques abiòtiques del medi i l’aliment disponible, des de indicadors de diferents fonts orgàniques fins a densitat de preses potencials de la megafauna.
Hem examinat els patrons espacials i temporals d’abundància i biomassa de les comunitats de megafauna bentopelàgica. Hem detectat canvis batimètrics relacionats amb els patrons de biomassa de determinades preses. També hem observat canvis estacionals relacionats amb l’estratificació versus l’homogeneïtat de la columna d’aigua. Els pics de producció primària superficial al febrer i de descàrrega dels rius a l’abril afavoriren majors densitats de megafauna i correspongueren a màxims de biomassa de megafauna a l’estiu després d’aproximadament 3-5 mesos. Determinades preses canalitzaren la matèria orgànica cap als predadors.
Hem estudiat els patrons estacionals en l’estructura de les xarxes tròfiques bentònica i bentopelàgica mitjançant l’anàlisi dels isòtops estables de carboni i nitrogen en la macro- i la megafauna i en la matèria orgànica particulada sedimentada i suspesa. També hem estudiat les dinàmiques tròfiques i els cicles reproductius d’espècies dominants de peixos i crustacis decàpodes.
Les correlacions entre δ15N-δ13C indicaren que les cadenes bentònica i bentopelàgica se sostenien en materials derivats del pic de producció primària superficial de finals d’hivern en períodes d’homogeneïtat de la columna d’aigua. Un espectre més ampli de fonts d’aliment, probablement provinents de fluxos advectius, sostenia la comunitat en períodes de columna d’aigua estratificada. La fauna bentònica presentà un contínuum en els valors dels coeficients dels isòtops estables indicatiu d’un ampli espectre d’estratègies alimentàries i d’una xarxa tròfica complexa amb almenys tres nivells tròfics.
L’anàlisi d’isòtops estables mostrà una segregació tròfica entre els peixos i els decàpodes. A més, tant l’anàlisi d’isòtops estables com de dietes revelaren que, dintre de cada tàxon, la comunitat s’estructurava en funció del gradient bèntic-pelàgic en la interfície aigua-sediment on les espècies de megafauna troben les preses i de la grandària dels propis predadors. Consistentment, hem identificat dues xarxes tròfiques basades en producció bentònica o pelàgica. Els canvis estacionals en l’estructura tròfica i en les dinàmiques alimentàries de la comunitat concordaven amb els patrons de producció de macrofauna. Els macroplanctòfags augmentaren l’activitat alimentària envers nova producció mesopelàgica després de l’hivern, i els bentòfags, envers macrofauna hiperbentònica i detritívora a l’estiu. A més, el consum d’aliment i la ingestió de preses més energètiques augmentaren en períodes pre-reproductius. Els canvis en l’aliment consumit per macroplanctòfags i bentòfags estaven determinats per variacions en diferents fonts de matèria orgànica. Els canvis en l’aliment usat pels macroplanctòfags depenien de les variacions en l’arribada de fitodetrits. Els dels bentòfags depenien de les variacions en la matèria orgànica sedimentada o suspesa. La maduració gonadal estava associada amb la disponibilitat d’aliment, i estava controlada principalment per l’aliment derivat del pic de producció primària superficial de finals d’hivern.Seasonality observed in diverse aspects of the deep-sea fauna is usually attributed to seasonal changes in food availability, but this relationship remains rather untested in megafaunal predators. The present thesis deals with the analysis of the seasonal dynamics of the bathyal benthic and benthopelagic megafauna communities, and their relationship with inputs and availability of food. The thesis is based on data collected in the four seasons of a natural year in the middle Catalan Slope (NW Mediterranean Sea). The Catalan Slope is an oligotrophic system influenced by vertical and advective fluxes of organic matter with marked seasonal fluctuations. We determined the seasonal patterns in the structure and functioning of the deep megafaunal assemblages, mainly fish and decapod crustaceans, and we explored the relationships between the faunal trends and data concerning the main processes providing food to bathyal depths as well as data on the abiotic characteristics of the environment and on the food available there, from indicators of different organic sources to densities of potential prey for megafauna. We examined the spatial and temporal patterns of abundance and biomass of benthopelagic megafauna assemblages. Bathymetric changes occurred, related to patterns in prey biomass. Seasonal changes also took place related to the stratification versus homogeneity of the water column. Both peaks of surface production in February and of river discharge in April favoured greater densities of megafauna and corresponded to a maximum in megafaunal biomass after ca. 3–5 months. Macrofaunal key prey taxa channelled the organic matter inputs to predators. We studied the seasonal patterns in the structure of the benthic and the benthopelagic food webs by analysing the carbon and nitrogen stable isotopes of macro- and megafauna and of sinking and sedimented particulate organic matter. We also studied the trophic dynamics and the reproductive cycles of dominant fish and decapod crustacean species. δ15N-δ13C correlations indicated that both the benthic and the benthopelagic communities relied on materials derived from the late-winter peak of surface primary production under water column homogeneity. A larger array of food sources, probably from advection, sustained the community in periods of water column stratification. In the benthic fauna, we observed a continuum of values in the isotope ratios that indicated a wide spectrum of feeding strategies and complex food webs consisting of at least 3 trophic levels. Stable isotope analysis showed that benthopelagic fish and decapod crustaceans were segregated from a trophic point of view. Besides, both stable isotopes and dietary analyses revealed that, within each taxon, the community was structured as a function both of the benthic-pelagic gradient in the water-sediment interface where megafauna species found their prey and of the own predator and prey size. Consistently, we identified two food webs based on pelagic (macroplankton) versus benthic production. Seasonal changes in food web structure and in the feeding dynamics of benthopelagic megafauna agreed with the patterns of macrofauna production. Macroplankton feeders increased feeding activity towards new mesopelagic production after winter, and benthic feeders increased feeding activity upon hyperbenthic and deposit feeding macrofauna in summer. Besides, food consumption and ingestion of more energetic increased in pre-reproductive periods. Changes in food consumed by mesopelagic or benthic consumers were associated with changes in different organic matter inputs. Changes in food consumed by macroplankton feeders depended on variations in phytodetritus inputs derived from the late-winter surface bloom of production. Changes in food consumed by benthic feeders depended on variations in sedimented or suspended organic matter. Gonad maturation was associated with the availability of food, and was mainly controlled by food derived from the late-winter surface bloom of production.
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Henderson, Susan Jane. "Analysis of the long-term slope stability of waste-rock dumps /." Title page, table of contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phh4972.pdf.
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Massa, Eric Macedo. "Estudo comparativo entre dois modelos geomorfológicos aplicados na Serra da Cantareira: bacia do Córrego do Bispo." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-01122009-154435/.
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Através de uma abordagem analítica entre dois modelos geomorfológicos elaborados por ROSS (1994) e pelo INPE (CREPANI et. al, 1996), foi estabelecida uma comparação entre variáveis relacionadas a aspectos capitais de ambos - critérios utilizados para a definição das unidades de paisagem e importância da variável relevo e um aspecto relacionado à aplicabilidade a adequação aos ambientes urbanos. Por apresentar uma diversidade de usos e ocorrência de áreas urbanas e preservadas, a bacia do córrego do Bispo, localizada na zona norte do município de São Paulo, foi escolhida como área teste. Estes modelos apresentaram boa aplicabilidade em ambientes preservados, destacando-se o modelo de Ross, que é mais eficaz em termos de previsibilidade. Em relação às áreas urbanas os modelos apresentaram resultados semelhantes, na medida em que diagnosticam fragilidades ambientais para áreas de ocupação não consolidadas e apresentam limitações em relação às áreas de ocupação consolidadas. Objetivando ainda uma contribuição ao modelo de Ross em nível experimental, incorporou-se a classificação de vertentes de RUEH (1975) baseada na geometria destas, à variável relevo do primeiro. Como resultado, foram obtidas diferenças significativas para algumas áreas em relação ao modelo originalmente proposto por Ross.An analytical approach between two geomorfphologic models elaborated by ROSS (1994) and INPE (CREPANI et. al, 1996), a comparison was estabilished between two variables related to capital aspects of both the criteria for the definition of landscape units, the importance of variable relief and its appliance to urban environments. For presenting a huge diversity of land uses and preserved urban areas, Córrego do Bispo basin located in north zone of São Paulo has been chosen as an experimental area. These models have shown a good applicability in preserved environmental, emphasizing specially Ross model, which is more useful in terms of predictability. Both models presented similar results in urban areas, while they make diagnostics of environmental fragilities to areas of non-consolidated occupation and presented restrictions about consolidated occupation areas. Also intending to contribute to Ross model in an experimental level, the slope classification of RUEH (1975) was included, based in its geometry to variable relief of Ross model. As a result, meaningful differences were obtained for some areas in relation to the model originally proposed by Ross.
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Hagerfors, Jonas. "Jämförelse av beräkningsprogrammen Novapoint Geosuite Stability och Geoslope SLOPE/W med avseende på släntstabilitet." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-384294.
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This thesis deals with the difference between two calculation programs for slope stability, namely Geoslope SLOPE/W and Novapoint GeoSuite Stability. The purpose of the thesis is to compare the two calculation programs with regard to the analysis of slope stability, as well as the two programs' handling of data. The two calculation programs use different Limit equilibrium methods to calculate safety factor and sliding surfaces for slopes. It can be expected that the result should be similar to one another, as well as the fact that both the calculation programs use different Limit equilibrium methods, but also when large differences in both safety factor and critical sliding surface give unreliable results. The thesis will also address the factors that may lie behind the fact that a possible stability failure should take place in a slope, as it gives an increased understanding of the analyzes that have been done. The work was carried out by modeling slopes with identical geometric relationships and identical material properties in the two calculation programs, a safety factor and a critical sliding surface for the slopes were developed for both programs and then compared with each other.Föreliggande examensarbete behandlar skillnaden mellan två beräkningsprogram när det kommer till släntstabilitet, nämligen Geoslope SLOPE/W och Novapoint GeoSuite Stability. Syftet med examensarbetet är att jämföra de båda beräkningsprogrammen avseende vid undersökning av släntstabilitet, samt de två programmens hantering av data. De två beräkningsprogrammen använder sig av liknande Limit equilibrium-metoder för att beräkna säkerhetsfaktor samt glidytor för slänter. Man kan förvänta sig att resultatet bör vara varandra likt då dels att de både beräkningsprogrammen använder sig av liknande Limit equilibrium-metoder, men också då stora skillnader i både säkerhetsfaktor och kritisk glidyta ger opålitligt resultat. Examensarbetet kommer även ta upp de faktorer som kan ligga bakom att ett eventuellt brott ska ske i en slänt, då det ger ökad förståelse för de analyser som gjorts. Arbetet utfördes genom att slänter med identiska geometriska relationer samt identiska materialegenskaper modellerades i de båda beräkningsprogrammen, en säkerhetsfaktor samt kritisk glidyta för slänterna togs fram för båda programmen och jämfördes sedan med varandra.
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Accarie, Hugues. "Dynamique sedimentaire et structurale au passage plate-forme/bassin : les facies cretaces et tertiaires du massif de la maiella (abruzzes, italie)." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0056.
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L'etude des series cretacees a tertiaires du massif de la maiella est basee sur la cartographie detaillee du domaine de transition plateforme-bassin et sur le leve d'un certain nombre de coupes. Elle est completee par une etude de la fracturation et de la fraction fine. Ces donnees permettent de proposer un modele d'evolution du domaine depuis le cretace superieur jusqu'au miocene. Quatre grandes discontinuites sedimentaires sont reconnues. L'analyse sedimentologique des ensembles permet de preciser le cadre biostratigraphique, la nature et l'organisation des depots et de reconnaitre les principaux facteurs gouvernant la sedimentation: ce sont les morphologies heritees, l'activite tectonique et les variations eustatiques
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Eddings, James B. "The Utility of Environmental DNA and Species Distribution Models in Assessing the Habitat Requirements of Twelve Fish Species in Alaskan North Slope Rivers." DigitalCommons@USU, 2020. https://digitalcommons.usu.edu/etd/7708.
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Subsistence fishing is a vital component of Alaska’s North Slope borough economy and culture that is being threatened by human disturbance. These threats mean the fish must be protected, but the size of the region makes conservation planning difficult. Fortunately, advances in species distribution models (SDMs), environmental DNA (eDNA), and remote sensing technologies provide potential to better understand species’ needs and guide management. The objectives of my study were to: (1) map the current habitat suitability for twelve fish species, occurring in Alaska’s North Slope,(2) determine if SDMs based on eDNA data performed similarly to, or improved, models based on traditional sampling data, and (3) predict how species distributions will shift in the future in response to climate change. I was able to produce robust models for 8 of 12 species that relate environmental characteristics to a species’ presence or absence and identify stream reaches where species are likely to occur. Unfortunately, the use of eDNA data did not produce useful models in Northern Alaskan rivers. However, I was able to generate predictions of species distributions into the future that should help inform management for years to come.
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Modi, Deepa. "Potential Utilization of FGD Gypsum for Reclamation of Abandoned Highwalls." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281477085.
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Griffiths, Thomas Richard. "An Enhanced Data Model and Tools for Analysis and Visualization of Levee Simulations." Diss., CLICK HERE for online access, 2010. http://contentdm.lib.byu.edu/ETD/image/etd3477.pdf.
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Beazley, Melanie J. "The significance of organic carbon and sediment surface area to the benthic biogeochemistry of the slope and deep water environments of the northern Gulf of Mexico." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969/534.
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Devkota, Jay P. "Variation of Manning’s Roughness Coefficient with Diameter, Discharge, Slope and Depth in Partially Filled HDPE Culverts." Youngstown State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1340991250.
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Hernandez, Tatiana X. "Rainfall-Runoff Modeling in Humid Shallow Water Table Environments." Scholar Commons, 2001. https://scholarcommons.usf.edu/etd/1537.
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Simulating the processes of rainfall and runoff are at the core of hydrologic modeling. Geomorphologic features, rainfall variability, soil types, and water table depths strongly influence hydrological process in Florida ecosystems. Topographic characteristics of the terrain define the stream paths and landscape. Alteration of these characteristics as a result of urban and/or agricultural developments, for example, can highly influence wetlands and river basin response. There are two predominant landforms in Florida: wetlands, where Variable Saturated Areas form near streams causing saturation excess runoff, and uplands where runoff is mainly generated by infiltration excess. The objective of this work is to analyze the impacts of geomorphologic and hydrologic characteristics on runoff mechanisms in humid environments such as Florida. In general, most research at the hillslope scale use hypothetical values of rainfall, sometimes non-realistic values, and single slope forms to explain the geomorphic and hydrologic process on Variable Saturated Areas. In this thesis, the complexity of hillslope processes on actual Florida topography is assessed by coupling a Digital Elevation Model with a two-dimensional variable saturated-unsaturated flow model called HYDRUS-2D. Actual rainfall records and soil parameters from the Characterization Data for Selected Florida Soils, Soil Survey were used to evaluate hydrologic impacts. A commercial software package, River Tools was used to display and extract topographic information from the Digital Elevation Models.
Results show that when inflitration excess runoff is dominant, infiltration and runoff are very sensitive to time resolution, especially for convective storms. When saturation excess occurs, runoff is not affected by rainfall intensity. However, saturated hydraulic conductivity, depth to the water table, slope and curvature highly influence the extent of Variable Saturated Areas. Results indicate runoff in shallow water table environments is produced mainly by subsurface storm runoff, running below the surface, except in hillslopes with concave curvature and mild slopes. Additionally, concave hillslopes generate more saturation excess runoff than straight and convex hillslopes.
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BARTON, JOHN M. H. "EFFECT OF MEDIA GRAIN SHAPE ON PHYSICAL CAPTURE OF PARTICLES IN A FILTER BED." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1092931427.
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Bramsäter, Jenny. "Closure of Lilla Bredsjön Tailings Dam : an Evaluation of the Long-Term Dam Safety Measures." Thesis, KTH, Vattendragsteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210320.
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The mining industry contributes to enormous amounts of waste all over the world, which places high demands on tailings dams. In Sweden, there are strict regulations regarding the management and treatment of tailings dams, but some dams that were built before these regulations existed still pose a threat to the environment. Lilla Bredsjön in Dalarna, Sweden, is an example of an old tailings dam that has not been treated properly. Boliden, which is the owner of the dam, and the county board of Dalarna are currently in meetings regarding the responsibilities of old polluted sites in Garpenberg, where Lilla Bredsjön is included. This study aims to investigate possible remediation measures of the dams at Lilla Bredsjön in order to achieve long- term stability upon closure of the facility. Lilla Bredsjön is 350 000 m2 large and contains three impoundments; dam 1 to the east, dam 2 to the south and dam 3 to the north. Dam 1 is seven meters at its highest point whereas dam 2 and 3 both are three meters high. All of the dams are classified to a consequence level of 3, meaning that the consequences in case of a failure would be negligible. They are built using the centerline method with impermeable cores of moraine. The tailings are partly covered with sludge mixed with biomass ash, but no proper closure method have been implemented. A geotechnical investigation was conducted to obtain more information about the geometry, construction and foundation of each dam. It could be observed that dam 1 consisted of a moraine core and support fill, both constructed using the Christmas tree principle. Dam 2 consisted of a coarse and fine filter in the upstream part of the dam, whereas the rest of the dam consisted of a moraine core. Dam 3 consisted of tailings and a moraine core, and was like dam 1 also constructed using the Christmas tree principle. The downstream slopes of all dams are moreover very steep with slope angles of approximately 34o. Seepage and stability calculations were therefore performed in the software GeoStudio. In GeoStudio, two different analysis tools were used; SEEP/W to calculate seepage and SLOPE/W to calculate slope stability. Four hydraulic load cases were analyzed in the calculations: present conditions, flooded conditions, potential maximum seepage and present conditions with lower permeability of the tailings. The result shows that all of the dams are unstable in their present con- ditions, both with original and lower permeability of the tailings, as well as at flooded conditions. The required safety factor is however fulfilled at potential maximum seepage. The stability highly depends on the pore pressure inside the dams, which in turn depends on the choice of closure method. Based on the result from the stability calculations it can be concluded that if a dry cover is chosen as the closure method, it will probably be enough to reinforce the existing dams to achieve long-term stability. If, on the other hand, a raised groundwater level is chosen, more extensive solutions in terms of for example completely new impoundments directly downstream of the existing ones are most likely needed. Before a decision regarding the closure method is taken, it is hence very difficult to come to a conclusion regarding suitable remediation measures of the dams.Gruvindustrin bidrar med enorma mängder avfall över hela världen, vilket ställer höga krav på gruvdammar. I Sverige finns det strikta förordningar gällande hanteringen och efterbehandlingen av gruvdammar, men en del dammar som byggdes innan dessa förordningar existerade utgör fortfarande ett hot mot miljön. Lilla Bredsjön i Dalarna är ett exempel på en gammal gruvdamm som inte blivit efterbehandlad tillräckligt. Boliden, som äger dammen, har möten med Länsstyelssen Dalarna angående ansvarsförhållanden gällande gamla förorenade områden i Garpenberg där även Lilla Bredsjön ingår. Denna studie syftar till att undersöka möjliga efterbehandlingsmetoder av dammarna vid Lilla Bredsjön för att uppnå långtidsstabilitet i samband med nedläggning av anläggningen. Lilla Bredsjön är 350 000 m2 stor och består av tre uppdämningar; damm 1 i öst, damm 2 i söder och damm 3 i norr. Damm 1 är sju meter som högst medan damm 2 och 3 båda är tre meter höga. Samtliga dammar är klassificerade till konsekvensklass 3, vilket betyder att konsekvenserna i händelse av ett dammbrott är försumbara. Dammarna är byggda med uppåtmetoden och har tätkärnor av morän. Magasinet är delvis täckt med slam utblandat med biobränsleaska, men ingen riktig efterbehandling har utförts. En geoteknisk undersökning genomfördes för att erhålla mer information om geometrin, konstruktionen och grundläggningen av varje damm. Det observerades att damm 1 består av en tätkärna av morän samt stödfyllning som båda konstruerades med julgransprincipen. Damm 2 består av ett grov- och finfilter i uppströmsdelen av dammen medan resten av dammen består av en tätkärna av morän. Damm 3 består av anrikningssand och en tätkärna av morän, och var liksom damm 1 konstruerad med julgransprincipen. Nedströmsslänterna på alla dammar är väldigt branta med en vinkel på ungefär 34o. Genomströmnings- och stabilitetsberäkningar genomfördes därför i programmet GeoStudio. I GeoStudio användes två olika verktyg; SEEP/W för att beräkna genomströmning och SLOPE/W för att beräkna släntstabilitet. Fyra olika hydrauliska belastningsfall analyserades i beräkningarna: normalfallet, överdämning, dimensionerat läckage och normalfallet med lägre permeabilitet på anrikningssanden. Resultatet visar på att samtliga dammar är instabila i deras nuvarande skick, beräknat på normalfallet med både ursprunglig och lägre permeabilitet på anrikningssanden, samt vid överdämning. Den erforderliga säkerhetsfaktorn är däremot uppfylld vid dimensionerat läckage. Stabiliteten är starkt beroende av portrycket inuti dammarna, vilket i sin tur är beroende av vilken efterbehandlingsmetod som väljs för magasinet. Baserat på resultatet från stabilitetsberäkningarna kan det konstateras att om torrtäckning väljs som efterbehandlingsmetod så räcker det förmodligen med att förstärka nuvarande dammar för att uppnå långtidsstabilitet. Om, å andra sidan, en förhöjd grundvattennivå väljs behövs med största sannolikhet en mer omfattande lösning, till exempel helt nya dammar direkt nedströms de nuvarande. Innan ett beslut gällande efterbehandlingsmetod av magasinet har tagits är det alltså väldigt svårt att dra en slutsats gällande den mest lämpliga efterbehandlingsmetoden av dammarna.
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Dorji, Karma Dema [Verfasser], and Rupert [Gutachter] Bäumler. "Soils as proxies of environmental fluctuations at the southern slopes of the Bhutan Himalayas / Karma Dema Dorji. Gutachter: Rupert Bäumler." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2016. http://d-nb.info/111015450X/34.
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Paul, Simon. "Urban Growth and Environmental Risks - A GIS-Based Analysis of Landslide Susceptibility in Bukavu (Democratic Republic of the Congo)." Thesis, Umeå universitet, Institutionen för geografi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-161193.
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The city of Bukavu, located at the eastern border of the Democratic Republic of Congo in the province of South Kivu, is a large and densely populated urban agglomeration that has experienced rapid growth during recent years. At the same time, Bukavu has been repeatedly struck by environmental hazards, especially by devastating landslides. The steepness of slopes in the city’s hilly and mountainous terrain is one of the most important factors contributing to landslide susceptibility, but the anthropogenic impact resulting from uncoordinated urban sprawl and land cover change additionally plays a crucial role in exacerbating the vulnerability of neighbourhoods. This thesis utilizes GIS software to provide cartographic material for landslide risk assessment in Bukavu and the city’s surroundings. It examines risk exposure related to slope inclination of densely built-up areas, the spatial development of the city and urban growth tendencies, and complements these aspects with information about land cover and the terrain.
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Okalp, Kivanc. "Soil Erosion Risk Mapping Using Geographic Information Systems: A Case Study On Kocadere Creek Watershed, Izmir." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606783/index.pdf.
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Soil erosion is a major global environmental problem that is increasing year by year in Turkey. Preventing soil erosion requires political, economic and technical actionsbefore these actions we must learn properties and behaviors of our soil resources. The aims of this study are to estimate annual soil loss rates of a watershed with integrated models within GIS framework and to map the soil erosion risk for a complex terrain. In this study, annual soil loss rates are estimated using the Universal Soil Loss Equation (USLE) that has been used for five decades all over the world. The main problem in estimating the soil loss rate is determining suitable slope length parameters of USLE for complex terrains in grid based approaches. Different algorithms are evaluated for calculating slope length parameters of the study area namely Kocadere Creek Watershed, which can be considered as a complex terrain. Hickey&
#8217
s algorithm gives more reliable topographic factor values than Mitasova&
#8217
s and Moore&
#8217
s. Satellite image driven cover and management parameter (C) determination is performed by scaling NDVI values to approximate C values by using European Soil Bureau&
#8217
s formula. After the estimation of annual soil loss rates, watershed is mapped into three different erosion risk classes (low, moderate, high) by using two different classification approaches: boolean and fuzzy classifications. Fuzzy classifications are based on (I) only topographic factor and, (II) both topographic and C factors of USLE. By comparing three different classified risk maps, it is found that! in the study area topography dominates erosion process on bare soils and areas having sparse vegetation.
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Sandy, Alexis Emily. "Environmental and Digital Data Analysis of the National Wetlands Inventory (NWI) Landscape Position Classification System." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33572.
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The National Wetlands Inventory (NWI) is the definitive source for wetland resources in the United States. The NWI production unit in Hadley, MA has begun to upgrade their digital map database, integrating descriptors for assessment of wetland functions. Updating is conducted manually and some automation is needed to increase production and efficiency. This study assigned landscape position descriptor codes to NWI wetland polygons and correlated polygon environmental properties with public domain terrain, soils, hydrology, and vegetation data within the Coastal Plain of Virginia. Environmental properties were applied to a non-metric multidimensional scaling technique to identify similarities within individual landscape positions based on wetland plant indicators, primary and secondary hydrology indicators, and field indicators of hydric soils. Individual NWI landscape position classes were linked to field-validated environmental properties. Measures provided by this analysis indicated that wetland plant occurrence and wetland plant status obtained a stress value of 0.136 (Kruskalâ s stress measure = poor), which is a poor indicator when determining correlation among wetland environmental properties. This is due principally to the highly-variable plant distribution and wetland plant status found among the field-validated sites. Primary and secondary hydrology indicators obtained a stress rating of 0.097 (Kruskalâ s stress measure = good) for correlation. The hydrology indicators measured in this analysis had a high level of correlation with all NWI landscape position classes due the common occurrence of at least one primary hydrology indicator in all field validated wetlands. The secondary indicators had an increased accuracy in landscape position discrimination over the primary indicators because they were less ubiquitous. Hydric soil characteristics listed in the 1987 Manual and NTCHS field indicators of hydric soils proved to be a relatively poor indicator, based on Kruskalâ s stress measure of 0.117, for contrasting landscape position classes because the same values occurred across all classes.
The six NWI fieldâ validated landscape position classes used in this study were then further applied in a public domain digital data analysis. Mean pixel attribute values extracted from the 180 field-validated wetlands were analyzed using cluster analysis. The percent hydric soil component displayed the greatest variance when compared to elevation and slope curvature, streamflow and waterbody, Cowardin classification, and wetland vegetation type. Limitations of the soil survey data included: variable date of acquisition, small scale compared to wetland size, and variable quality. Flow had limitations related to its linear attributes, therefore is often found insignificant when evaluating pixel values that are mean of selected pixels across of wetland landscape position polygons. NLCD data limitations included poor quality resolution (large pixel size) and variable classification of cover types. The three sources of information that would improve wetland mapping and modeling the subtle changes in elevation and slope curvature that characterize wetland landscapes are: recent high resolution leaf-off aerial photography, high-quality soil survey data, and high-resolution elevation data.
Due to the data limitations and the choice of variables used in this study, development of models and rules that clearly separate the six different landscape positions was not possible, and thus automation of coding could not be attempted.Master of Science
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Majara, Ntina. "Land degradation in Lesotho : a synoptic perspective." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1645.
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Nasr, Jonathan A. "Development of a Design Guideline for Bridge Pile Foundations Subjected to Liquefaction Induced Lateral Spreading." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4160.
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Effective-stress nonlinear dynamic analyses (NDA) were performed for piles in liquefiable sloped ground to assess how inertia and liquefaction-induced lateral spreading combine in long-duration vs. short-duration earthquakes. A parametric study was performed using input motions from subduction and crustal earthquakes covering a wide range of earthquake durations. The NDA results were used to evaluate the accuracy of the equivalent static analysis (ESA) recommended by Caltrans/ODOT for estimating pile demands. Finally, the NDA results were used to develop new ESA methods to combine inertial and lateral spreading loads for estimating elastic and inelastic pile demands.
The NDA results showed that pile demands increase in liquefied conditions compared to nonliquefied conditions due to the interaction of inertia (from superstructure) and kinematics (from liquefaction-induced lateral spreading). Comparing pile demands estimated from ESA recommended by Caltrans/ODOT with those computed from NDA showed that the guidelines by Caltrans/ODOT (100% kinematic combined with 50% inertia) slightly underestimates demands for subduction earthquakes with long durations. A revised ESA method was developed to extend the application of the Caltrans/ODOT method to subduction earthquakes. The inertia multiplier was back-calculated from the NDA results and new multipliers were proposed: 100% Kinematic + 60% Inertia for crustal earthquakes and 100% Kinematic + 75% Inertia for subduction earthquakes. The proposed ESA compared reasonably well against the NDA results for elastic piles. The revised method also made it possible to estimate demands in piles that performed well in the dynamic analyses but could not be analyzed using Caltrans/ODOT method (i.e. inelastic piles that remained below Fult on the liq pushover curve). However, it was observed that the pile demands became unpredictable for cases where the pile head displacement exceeded the displacement corresponding to the ultimate pushover force in liquefied conditions. Nonlinear dynamic analysis is required for these cases to adequately estimate pile demands.
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Kasiulevičius, Rimas. "Krūmų ir medžių šaknų ardomojo poveikio įvertinimas tiriant tvenkinių šlaitų tvirtinimo gelžbetonines plokštes." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100615_124852-86043.
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Tvenkinių šlaitų tvirtinimo plokščių (toliau – ŠTP) būklę bei ilgaamžiškumą lemia jas veikiantys poveikiai ir apkrovos, susidarantys dėl agresyvios aplinkos, klimato poveikio bei kitų veiksnių. Vienas iš žalingų reiškinių – dėl prastos šlaitų priežiūros išaugę drėgmę mėgstantys krūmai (pvz. karklai) ar net medžiai, kurių šaknys ieškodamos drėgmės, iškilnoja ir suskaldo šlaitų tvirtinimo plokštes. Darbo tikslas – įvertinti krūmų ir medžių šaknų ardomojo poveikio reikšmę Lietuvos tvenkinių šlaitų tvirtinimo gelžbetoninių plokščių būklei. Šiam tikslui pasiekti buvo atlikta literatūros analize, įvertinant tvenkinių šlaitų tvirtinimo plokštes veikiančius veiksnius ir apkrovas. 2008 – 2009 m. mokslinių ekspedicijų metu natūriniais tyrimais įvertinta 16 tvenkinių šlaitų tvirtinimo gelžbetoninių plokščių būklė pagal STR.1.12.03:2006. Remiantis natūrinių tyrimų rezultatų analize detalesniam tyrimui parinktos Antanavo hidroelektrinės žemutinio bjefo gelžbetoninės plokštės, kurių suardymo pobūdis leidžia teigti, kad šlaitų tvirtinimo plokštės buvo suardytos veikiant medžio šaknims.Durability and technical state of reinforced concrete slabs for ponds slope protection depends on the maintenance circumstances – aggressive environmental impacts, loads from climate, etc. One of the harmful phenomenons are moisture–loving shrubs (for example, wicker), which appeared because of the bad slope maintenance or even trees, the roots of which heave and shatter (when searching for moisture) slabs for slope protection. The aim of the work was to evaluate the destructive force of the trees and shrubs roots on the reinforced concrete slabs for slope protection. For the achievement of this goal the literature analysis was carried out in order to determine factors and loads effecting slabs for slope protection. During the scientific expeditions in 2008–2009 the condition state of the reinforced concrete slope protection slabs of 16 ponds were evaluated by field investigations according to STR. 1.12.03:2006. Following the analysis of the results of field investigations the reinforced concrete slabs from the lower pond of the Antanavas hydroelectric power station were chosen for the more detailed investigation. The destructive character of these slabs allows stating that slope protection slabs were destructed because of the trees roots.
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Skog, Emma. "Geological factors affecting the channel type of Bjur River in Västerbotten County : A study concerning the connection between surficial geology, landforms, slope and different hydrological process domains in a stream catchment above the highest shoreline." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-160914.
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Process domains categorizes sections of streams according to its local dominant processes. These processes often reflect on the local ecology and the streams appearance. But the underlying reason why these different process domains are formed are still not completely certain. In this study the distribution of the process domains: lakes, rapids and slow-flowing reaches in the Bjur River catchment were compared to the geological factors of slope, surficial geology and landforms to see if any connections could be found. The possibility of using GIS (geographic information systems) and remote data to distinguish these stream types and to connect them to the different studied geological factors were also examined. The hypothesis for this study is that the geological factors of slope, surficial geology and landforms all should have an influence over the distribution of the process domains in Bjur River. The analysis was executed through map-studies in ArcGIS and statistical analysis in Excel. All process domains showed statistical significance towards the studied geological factors. The slope was generally steeper in the rapids than in slow-flowing reaches and lakes. The surficial geology displayed more fine-grained sediment (peat) in proximity to lakes and slow-flowing reaches whilst till was more abundant close to rapids. Hilly moraine landscapes were most common around lakes, while rapids displayed a high percentage of glacio-fluvially eroded area. Slow-flowing reaches also showed to have around 44% of its studied points around glacio-fluvially eroded area, and 43% at areas without any major landforms. Even if the statistical analysis and figures display a difference between the different process domains, it is still difficult to say which of these geological factors that plays the most crucial role for their development. However, by using remote data and through studies over slope, adjacent surficial geology and landforms the different process domains can be differentiated from one another.
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Mendes, Pablo Bettio. "Análise comparativa de elementos de bioengenharia no controle do processo erosivo de um talude de alta inclinação em um curto período de tempo." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/157282.
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A erosão dos solos é fenômeno natural que ocorre tanto em áreas rurais como urbanas, atuando através da remoção e arraste de material, tendo consequências muito sérias ocasionando diversas perdas financeiras e até de vidas humanas. A necessidade de conter ou controlar esse processo de degradação inspirou o desenvolvimento de várias tecnologias ligadas à área de bioengenharia. Duas delas, biomanta e hidrossemeadura, são atualmente vendidas separadamente no mercado provavelmente por razões comerciais, mas possuem o potencial de ser trabalhadas de maneira integrada. O objetivo do presente trabalho foi testar a eficácia do uso integrado de duas técnicas de controle de erosão causada pela água em encostas e taludes: biomanta e hidrossemeadura. O trabalho foi realizado no município de Sorocaba em um talude com forte pendente disponibilizado dentro do Campus da Faculdade de Tecnologia (FATEC). Foram usados materiais de baixo custo, além do uso de rejeitos de material proveniente de cortes de vegetação de baixo porte que muitas vezes não tem um destino adequado. Para tanto foram construídas oito parcelas retangulares de aproximadamente seis metros de extensão por um metro de largura. Duas destas parcelas foram mantidas continuamente descobertas (condição controle de terreno natural) e as outras seis foram cobertas / protegidas com mantas biodegradáveis, sementes ou sistema integrado de palha e sementes. Ao todo foram construídos quatro pares, cada um deles com uma técnica diferente de combate a erosão. Durante a pesquisa, foram avaliadas e quantificadas as mudas das espécies que germinaram, também foi medido o volume de chuva durante o período. Sem prejuízo, fez-se, também, a quantificação do volume do material erodido (sedimento) em cada tipo de recobrimento após cada evento de chuva.
Soil erosion is a natural phenomenon that occurs in rural and urban areas, acting through the removal and dragging of material, with very serious consequences causing several losses including human lifes. The need to contain or control this degradation process has inspired the development of several technological alternatives linked to the area of bioengineering. Two of them are currently sold separately on the market, probably for commercial reasons, but have the potential to be worked on in an integrated fashion. The aim of the present work is to test the effectiveness of two techniques integrated to avoid erosion caused by water on slopes used together: bio-blanket and hydroseeding. The work was carried out in Sorocaba in a slope with strong inclination made available within the Campus of the Faculdade de Tecnologia (FATEC). For the work, low cost materials were used as the litter usually coming from the tailings, vegetation cuts that often did not have an adequate destination. For this, eight rectangular plots of approximately six meters in length by a meter of width each were constructed. Two of these plots were kept continuously discovered (natural land control condition) and the other six were covered / protected with biodegradable blanket, seeds or integrated straw and seed system. Altogether there are four pairs compared, each with a different solution from the each other. During the research, the seedlings of the species that germinated were evaluated and quantified. The volume of rain was quantified and also the volume of the eroded material (sediment) in each type of cover were also measured right after every rain event
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Amorim, Raul Reis 1981. "Análise geoambiental como subsídio ao planejamento no uso e ocupação das terras da zona costeira da região Costa do Descobrimento (Bahia)." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/286678.
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Orientador: Regina Célia de OliveiraTese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências
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Resumo: O estudo ambiental tem revelado sobretudo nas últimas décadas, um caráter interdisciplinar nas pesquisas pautadas sobre a dinâmica dos agentes naturais, frente à crescente pressão de uso do espaço, materializada por conflitos de diversas ordens, sejam esses, históricos, políticos, culturais, religiosos, enfim, relações humanas que se estruturam sobre o território e impõem a esse espaço níveis diversos de interferência no mecanismo natural preexistente. Nesse contexto, entender as relações das sociedades humanas com a natureza, dentro de uma perspectiva absolutamente dinâmica, que envolve os aspectos culturais, sociais, econômicos e naturais, exige adotar um procedimento analítico que leve em consideração a sociedade nos seus diversos estágios de desenvolvimento, e remeta a uma visão holística da organização do espaço. Sendo assim, a ciência geográfica, tendo como objeto de análise o espaço geográfico, possibilita, sob um olhar crítico, a realização de estudos ambientais integrados, de maneira a dar suporte técnico científico para a elaboração de estudos como aqueles relacionados ao zoneamento ambiental, que podem estar inseridos nas políticas públicas, contribuindo no planejamento e tomada de decisão. Considerando o exposto, esta tese se propõe à elaboração de um Zoneamento Ambiental, como subsidio ao planejamento do uso e ocupação das terras da zona costeira da região Costa do Descobrimento, situada na região Extremo Sul do Estado da Bahia. Tal proposta de estudo justifica-se por três fatores: (a) essa região é uma das áreas de povoamento pioneiro do território nacional, área em que o agente antrópico atua como ator na configuração da paisagem há mais de cinco séculos; (b) a área tem sofrido transformações no uso e ocupação das terras, não considerando os níveis de fragilidade ambiental da área em estudo, o que acentua os problemas ambientais; e (c) a inexistência de estudos que integrem os sistemas naturais aos sistemas antrópicos no planejamento no uso e ocupação da zona costeira da região Costa do Descobrimento. Nos últimos quarenta anos, ela se tornou uma das regiões mais dinâmicas economicamente do Estado da Bahia, e também é um dos principais destinos turísticos do Brasil. Para atingir tal meta, adotou-se a metodologia proposta por Rodriguez, Silva e Cavalcanti (2004), enfatizando a análise funcional da paisagem. As diferentes atividades econômicas implantadas na Região Costa do Descobrimento, nos últimos 40 anos possibilitaram a formação de diversos sistemas ambientais com fragilidades complexas e que sofrem há séculos pressões de uso, resultando em problemas ambientais que alteram a dinâmica dos sistemas naturais e também o modo de viver da população local
Abstract: The environmental study has revealed especially in recent decades in an interdisciplinary research guided on the dynamics of natural agents face the growing pressure of space usage, embodied by conflicts of various orders, are those, historical, political, cultural, religious, in order, human relations that are structured on the territory and impose on this space several levels of interference in the natural pre-existing mechanism. In this context, understanding the relationship of human societies and nature, within an absolutely dynamic perspective that involves cultural, social, economic and natural, requires adopting an analytical procedure that takes into account the society in their various stages of development, which refers to a holistic view of space organization. Thus, the geographical science as the object of the geographic analysis, allows a critical eye on the implementation of integrated environmental studies in order to provide technical support for the development of scientific studies such as those related to environmental zoning that can be inserted on policy contributing public in planning and decision taken. Considering the above, this thesis proposes the development of an environmental zoning as support for planning the use and occupation of the coastal region of the Discovery Coast, located in the extreme south of Bahia. This proposed study is justified by three factors: (a) this region is a pioneer of the populated areas of the country, an area in which the agent acts as man-made actor in shaping the landscape for more than five centuries, (b) area has undergone significant changes in the use and occupation of land, not considering the levels of environmental fragility of the study area, which emphasizes environmental issues, and (c) the lack of studies integrating natural systems to anthropogenic systems in use in planning and occupation of the coastal region of the Discovery Coast, that the last forty years has become one of the economically most dynamic regions of the state of Bahia, and is also one of the major tourist destinations in Brazil. To achieve this goal, we adopted the methodology proposed by Rodriguez, Cavalcanti, Silva and Cavalcanti (2004), emphasizing the functional analysis of the landscape. The different economic activities implemented in the Discovery Coast Region in the last 40 years has enabled the formation of different complex environmental systems with frailties and suffering centuries of use pressures resulting in environmental problems that affect the dynamics of natural systems and also the way of life of local population
Doutorado
Análise Ambiental e Dinâmica Territorial
Doutor em Ciências
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Dynesius, Aron. "Spridningsbegränsningar för sik (Coregonus lavaretus) : En GIS-baserad studie." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184023.
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An important question in determining species composition in a lake is what species has had the chance to reach the lake in the first place. The aim of this study was to examine natural stream connectivity limitations for whitefish (Coregonus lavaretus) between lakes, and to contribute to the development and evaluation of GIS-based methods to answer this question. 497 lakes with identified downstream source lakes, were classified as naturally colonized or introduced whitefish populations, reflecting the possibilities for whitefish to reach the lake naturally. Data of maximum stream slope and stream length between each lake pair was generated by Stefan Blumentrath, NINA. Maximum stream slope was measured on two different resolutions of stream length for comparison, one on slope over 10 m and one over 150m. A subset of lakes was manually examined in geographic information systems and compared to maps and aerial photos to evaluate the data and compare the results with the full dataset. False slope maximums were corrected and streams with much human alteration around a possible natural slope maximum was removed from the small dataset. The two datasets were analyzed using logistic regression models. Akaikes information criterion (AIC) showed that the optimal model, for both datasets, was the one using only slope maximum as predictor, and slope over 150m gave better results than 10m. A k50-coefficient, the value of a predictor that results in 50% probability of colonization, was introduced as an approximate of when the predictor forms a connectivity hinder. The k50-corefficient was estimated to 2,08±0,22° (±standard error) for slope over 150m for the big dataset and 2,58±0,20 for the small. Weaknesses in the data were distinguished and improvements for future fish connectivity studies are suggested.
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O'Shea, Thomas A. "Using an Inventory of Unstable Slopes to Prioritize Probabilistic Rockfall Modeling and Acid Base Accounting in Great Smoky Mountains National Park." Digital Commons @ East Tennessee State University, 2021. https://dc.etsu.edu/etd/3952.
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An inventory of unstable slopes along transportation corridors and performance modeling are important components of geotechnical asset management in Great Smoky Mountains National Park (GRSM). Hazards and risk were assessed for 285 unstable slopes along 151 miles of roadway. A multi-criteria model was created to select fourteen sites for two-dimensional probabilistic rockfall simulations and Acid Base Accounting (ABA) tests. Simulations indicate that rock material would likely enter the roadway at all fourteen sites. ABA test results indicate that influence of significant acid-producing potential is generally confined to slaty rocks of the Anakeesta Formation and graphitic schist of the Wehutty Formation. The research illustrates an approach for prioritizing areas for site-specific investigations towards the goal of improving safety in GRSM. These results can help park officials develop mitigation strategies for rockfall, using strategies such as widening ditches and encapsulating acidic rockfall material.
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Åberg, Elin. "Is it possible to define different process domains in stream systems based on remote data? : Comparing surficial geology, geomorphological characteristics in the landscape and channel slope between lakes, rapids and slow-flowing reaches." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-162933.
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Restoration of stream channels have become a common way of trying to restore both the channels and the ecosystems that earlier have been channelized mainly to facilitate the movement of timber. According to previous studies a lot of the restoration has been performed without a sufficiently detailed plan and with too little focus on how the landscape interplay with the restoration, which makes the potential to learn from possible mistakes minimal. In this study, a hydrological analysis of Hjuken river was done to examine if remote data through an analysis using GIS could be used for identifying three different process domains (lake, slow-flowing reaches and rapids), and if it is possible to determine which process domain it is by examining three different variables: channel slope, surficial geology and the geomorphologic characteristics in the landscape. Based on the statistical treatment and the analysis of the data, the result shows a significant difference between every process domain and variable except for the channel slope when it comes to slow-flowing reaches and rapids. This tells us that all the variables that has been analysed could be a crucial factor in most of the cases. However, the result does not seem reliable compared to previous studies. The conclusion of the study is that the error from the identification of the process domains is from the orthophotos. Remote data is too weak to use as the only source for this kind of analysis. However, the definition of process domains is probably more diffuse than today’s description. There needs to be more studies on each process domain, it is probably not enough with three different types, either there should be subclasses for each process domain or even more process domains.
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Brito, Gilmar Gonçalves de. "Modelo de monitoramento de deslizamento de encostas por meio de sensor multiparamétrico." Universidade Católica de Pernambuco, 2013. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=947.
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Fenômenos de deslizamentos de encostas ocorrem em todo o mundo em diversas condições climáticas e de terrenos, custando bilhões de dólares e produzindo milhares de mortes, agravando problemas ambientais, econômicos e políticos. Um
problema sério que se associa à questão dos deslizamentos de encostas é o crescimento populacional e a ocupação desordenada das encostas, caracterizando os deslizamentos como uma questão geopolítica e econômica. Ações para mitigar os problemas decorrentes desses fenômenos de deslizamentos incluem o Monitoramento Ambiental das áreas de maior susceptibilidade e o Manejo da População, quando submetidas a elevado risco de deslizamento. Os processos de
monitoração consistem na coleta de um conjunto de sinais e parâmetros, provenientes do solo das encostas, que possam ser usados para o reconhecimento das dinâmicas dos solos. Combinando os sinais provenientes do solo e parâmetros
que reflitam os fatores climáticos e antrópicos, causadores de desestabilizações e deslizamentos, torna-se possível utilizar estes dados combinados em modelos de avaliação de risco para realizar a Predição de Deslizamentos. No Contexto
Brasileiro, existe uma forte relação entre chuvas intensas e deslizamentos de encostas, devido aos fenômenos de escoamento de águas infiltradas no solo e na erosão decorrente, sendo, portanto, o monitoramento preditivo das primeiras camadas do solo um importante recurso para a detecção das áreas de eminente risco de deslizamento. Diversas abordagens para a monitoração dos solos foram
apresentadas internacionalmente, sendo estas abordagens baseadas em diversas tecnologias, como exemplos podem ser citadas as técnicas de ondas acústicas no solo, detectores de umidade relativa e pluviometria seletiva. Essas abordagens
podem tirar proveito do recente paradigma de Redes Sensores, baseados em dispositivos computacionais móveis de baixo consumo, movidos a baterias, que podem formar redes de trocas de dados baseadas em redes sem fio, permitindo a
conexão de diversos sensores de solo, espalhados ao longo das encostas, formando um sistema de coleta destes dados de sensores em tempo real para posterior processamento e avaliação de riscos. Frente ao exposto, este trabalho propõe um sistema de monitoramento baseado em rede sensores, capaz de estimar o risco eminente de deslizamento. O sistema proposto considerou quatro dimensões do problema de desenvolvimento e prototipação do sistema de monitoramento: (1) Proposição de um Ambiente de Simulação Física, a partir da criação de um ambiente de testes em laboratório utilizando escala reduzida; (2) Reconhecimento tecnológico e refinamento de propostas de sistemas pré-existentes, que tenham a mesma finalidade, já descritos na literatura, sejam eles projetos acadêmicos ou sistemas já comercialmente disponíveis; (3) Desenvolvimento de um Sensor
Inteligente Multiparamétrico; (5) desenvolvimento de uma Rede de Monitoramento para coleta de dados vindos da encosta e processamento local. Este trabalho apresenta, como contribuição técnico-científica principal, um ambiente de simulação e monitoração, sendo este ambiente relevante para estudos das dinâmicas dos deslizamentos, bem como para a prototipação de redes de monitoração para aplicações em ambientes reais, para geração de informação sobre os riscos de deslizamento, uteis para as atividades de contingenciamento dos defeitos de deslizamento por parte da Defesa Civil.Landslides occur around the world, in various conditions of weather and terrain, costing billions of dollars, causing thousands of deaths and worsening environmental, economic and political problems. A serious question associated with landslides is the disordered of human occupation - characterizing a geopolitical and economic issue. Actions to mitigate the problems arising from this phenomenon include environmental monitoring of the areas of greatest susceptibility for managing the higher risk population. The monitoring processes consist of recognizing soil dynamics and climatic factors, responsible for causing destabilization and landslides. In the Brazilian context, there is a strong relationship between heavy rains and landslides, since the phenomenon of runoff water infiltrated the soil and produces erosion. Therefore, a predictive monitoring of the first soil layers is an important feature for detecting areas of imminent risk of slippage. Several approaches for monitoring were presented internationally, they are based on different technologies, such as acoustic waves in the soil; detectors of relative humidity and rainfall selective analysis. All these approaches are anchored in the paradigm of remote sensing and smartsensor networks. Based on that, this paper proposes a model to estimate the imminence of of landslides risk. The proposed model is built on four pillars: (i) proposing a physics simulation environment, from the creation of a laboratory scale test environments, (ii) recognizing the technology and refinement of pre-existing models, (iv) developing of multiparametric smart sensor and (v) developing of a peer-to-peer network of sensors. This study aggregates to the scientific and technical contribution a framework for monitoring, useful for studying of landslides dynamics. Such framework is crucial for prototyping monitoring networks to be used by civil defense.
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Barreto, Karla Thais. "DINÂMICA PEDOGEOMORFOLÓGICA NA FORMAÇÃO FURNAS - BACIA DO RIO VERDE/ PONTA GROSSA - PR." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2016. http://tede2.uepg.br/jspui/handle/prefix/588.
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The dynamics pedogeomorphological enables understanding of pedomorphogenesis by the study of soil and relief in the genesis of landscapes, since they depend on the same formation factors. This study shows itself as an important tool to environmental planning. The research was conducted in the Furnas Formation occurrence area in the basin of the Verde river in Ponta Grossa (PR) with the objective to verify the pedogeomorphic behavior on the convex slopes of the Formation, according to drainage pattern and current use of Earth. Was chosen four representative toposequences of agricultural use and proceeded with the compartmentation of the slopes into three segments for the characterization of soils until the 6th categorical level. Twelve profiles were sampled at the surface and subsurface material with which routine particle size and chemical analysis were performed. The physical and chemical properties of the soil were compared between the studied slopes. In these, also, were inferred information about the evolution of the landscape. A higher variability of soils was observed in the younger erosional surfaces than in the older and depositional. The middle third and top segments of the slopes were those with higher and lower differentiation of soils, respectively. Among slopes, area 03 was the one that showed greater variability of soil. Has detected the occurrence of a reworking material from the Ponta Grossa Formation in the transition area of the two lithologies, which was responsible for the different behavior of the various attributes of the soil. There was regular decrease in pH, % of clay and base saturation, and increase, % of sand, aluminum saturation, CTC/100g of clay and the relationship silt / clay, from the most evolved soils to the latest. The identification of some factors such as: position occupied by the soil on the slope, degree of evolution of soils and formation of ferruginous crusts in the subsurface enabled the understanding of the relationship between the dynamics pedomorphogenic, mainly by sediment transport that contributes to siltation increasingly intense in rivers of this region.
A dinâmica pedogeomorfológica possibilita a compreensão da pedomorfogênese, pelo estudo do solo e relevo na gênese das paisagens, já que dependem dos mesmos fatores de formação. Esse estudo mostra-se uma importante ferramenta ao planejamento ambiental. A pesquisa foi conduzida na área de ocorrência da Formação Furnas, na bacia do rio Verde, município de Ponta Grossa (PR) com o objetivo de verificar o comportamento pedogeomórfico em vertentes convexas da referida Formação geológica, segundo padrão de drenagem e uso atual da Terra. Escolheu-se 4 topossequências representativas de uso agropecuário e procedeu-se com à compartimentação das vertentes em três segmentos para a caracterização dos solos até o 6° nível categórico. Foram amostrados 12 perfis em superfície e subsuperfície, material com o qual foram realizadas análises granulométricas e químicas de rotina. Os atributos físicos e químicos dos solos foram comparados entre as vertentes estudadas. Nestas, também, foram inferidas informações sobre a evolução da paisagem. Observou-se maior variabilidade de solos nas superfícies mais jovens e erosionais do que nas mais antigas e deposicionais. Os segmentos de vertente terço médio e topo, foram os que apresentaram maior e menor diferenciação de solos, respectivamente. Entre as vertentes, a área 03 foi a que demonstrou maior variabilidade dos solos. Detectou-se a ocorrência de um material de retrabalhamento da Formação Ponta Grossa na área de transição das duas litologias, que foi o responsável pelo comportamento diferenciado de vários atributos dos solos. Houve decréscimo regular nos valores de pH, % de argila e saturação por bases, e, elevação, da % de areia, saturação por alumínio, CTC/100g de argila e da relação silte/argila, dos solos mais evoluídos para os mais recentes. A identificação de alguns fatores, tais como: posição ocupada pelos solos na vertente, grau de evolução dos solos e formação de crostas ferruginosas em subsuperfície possibilitaram o entendimento das relações entre a dinâmica pedomorfogênica, principalmente pelo transporte de sedimentos que contribui para o assoreamento cada vez mais intenso nos rios da região.
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Stewart, Anne M. "Estimation of urban-enhanced infiltration and groundwater recharge, Sierra Vista subbasin, southeast Arizona USA." Thesis, The University of Arizona, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3618344.
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This dissertation reports on the methods and results of a three-phased investigation to estimate the annual volume of ephemeral-channel-focused groundwater recharge attributable to urbanization (urban-enhanced groundwater recharge) in the Sierra Vista subwatershed of southeastern Arizona, USA. Results were used to assess a prior estimate.
The first research phase focused on establishment of a study area, installation of a distributed network of runoff gages, gaging for stage, and transforming 2008 stage data into time series of volumetric discharge, using the continuous slope-area method. Stage data were collected for water years 2008 - 2011.
The second research phase used 2008 distributed runoff data with NWS DOPPLER RADAR data to optimize a rainfall-runoff computational model, with the aim of identifying optimal site-specific distributed hydraulic conductivity values and model-predicted infiltration.
The third research phase used the period-of-record runoff stage data to identify study-area ephemeral flow characteristics and to estimate channel-bed infiltration of flow events. Design-storm modeling was used to identify study-area predevelopment ephemeral flow characteristics, given the same storm event. The difference between infiltration volumes calculated for the two cases was attributed to urbanization. Estimated evapotranspiration was abstracted and the final result was equated with study-area-scale urban-enhanced groundwater recharge. These results were scaled up to the Sierra Vista subwatershed: the urban-enhanced contribution to groundwater recharge is estimated to range between 3270 and 3635 cubic decameters (between 2650 and 2945 acre-feet) per year for the period of study. Evapotranspirational losses were developed from estimates made elsewhere in the subwatershed. This, and other sources of uncertainty in the estimates, are discussed and quantified if possible.
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Šadzevičius, Raimondas. "Aplinkos poveikio žemių užtvankų šlaitų tvirtinimo gelžbetoninėms plokštėms modeliavimas ir analizė." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20051108_145159-47758.
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In the dissertation evaluated frost influence to the change of physical–mechanical properties of the reinforced concrete slabs for earth dam slope protection. Established ice thermal expansion linear load acting the slabs and proposed more exact calculation of this load. Evaluated deterioration indices and defects influence to slabs state and durability.
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Paul, Anne. "Modélisation numérique des déformations d'un édifice volcanique : applications au Mont St Helens." Grenoble 1, 1986. http://www.theses.fr/1986GRE10006.
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La mesure des déplacements de surface liés â l'activité volcanique est une méthode très utilisée dans la surveillance et l'étude des volcans actifs. De nombreux modèles mécaniques ont été réalisés pour tenter de déduire la structure interne de ces données de déplacements, et notamment pour localiser les chambres magmatiques. Mais ils négligent tous le caractère fortement hétérogène et discontinu des édifices volcaniques. Un nouveau modèle permettant précisément l'étude des milieux hétérogènes et fracturés est utilisé. Son hypothèse de base est que l'édifice se comporte comme s'il était constitué d'un assemblage de blocs se déplaçant les uns par rapport aux autres. L'éruption très bien documentée du Mont St Helens (1980) sert de test pour cette méthode de blocs, en permettant de comparer déplacements calculés et déplacements mesurés. Quatre modèles bi-dimensionnels de ce volcan sont construits à partir d'une coupe géologique nord-sud. Chacun d'eux permet de tester l'effet d'un paramètre du modèle (géométrie, conditions aux limites, coefficient de frottement entre blocs, chemin de sollicitation). L'intrusion d'un dôme de lave à l'intérieur du flanc nord est simulée par l'application d'une montée en pression incrémentale puis les modèles sont soumis à une accélération horizontale simulant un séisme. Les résultats de cette modélisation mettent en évidence la dépendance des modes de déformation et de rupture vis à vis du coefficient de frottement entre les blocs. On obtient un assez bon accord avec les observations pour la plus faible des deux valeurs de ce coefficient testées (O. S). La rupture du flanc nord en grand glissement de terrain se produit aussi bien sous la seule influence de la montée en pression que sous pression et séisme combinés. Mais le second type de chargement donne un meilleur accord des résultats avec la réalité, et confirme ainsi qu'un séisme était bien à l'origine de l'éruption. Enfin, on discute, à la lumière de ces résultats, de la possibilité d'appréhender les structures internes et les mouvements du magma, à partir des mesures de déplacements de surface