Dissertations / Theses on the topic 'Fluvial geomorphology'
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Alqahtani, Faisal A. "3D seismic geomorphology of fluvial systems." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/6180.
Full textSaville, Christopher. "Fluvial and tectonic geomorphology of orogenic plateaux." Thesis, Durham University, 2013. http://etheses.dur.ac.uk/7718/.
Full textWarwick, Gail L. "The geomorphology and sedimentology of terminal fluvial systems." Thesis, University of Aberdeen, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487421.
Full textWilson, David William. "On the problem of indeterminacy in fluvial geomorphology." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246883.
Full textClement, David T. "Fluvial geomorphology of the Yukon River, Yukon Flats, Alaska." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0015/MQ47994.pdf.
Full textDietrich, James. "Applications of Structure-from-Motion Photogrammetry to Fluvial Geomorphology." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/18701.
Full textSimpson, Christopher J. "Fluvial geomorphology of the sand bed Milk River, northern Montana." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0020/MQ48043.pdf.
Full textSchaney, Mitzy L. "Geologic and geomorphic controls of alluvial island location in Cheat River, West Virginia." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4159.
Full textTitle from document title page. Document formatted into pages; contains v, 130, [12] p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.
Pietsch, Timothy J. "Fluvial geomorphology and late quaternary geochronology of the Gwydir fan-plain." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060720.153247/index.html.
Full textObaid, Ahmed Kadhim. "Tectonic and fluvial geomorphology of the Zagros fold-and-thrust belt." Thesis, Durham University, 2018. http://etheses.dur.ac.uk/12894/.
Full textMoreira, Gina-Lee. "Fluvial system restoration – case study: river Tua." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11096.
Full textThe purpose of this thesis is to provide river basin managers with a framework for river restoration. To that end, it presents and discusses the relevant information on the current condition of the river Tua, in northern Portugal, and establishes what can be done to restore the river basin in order to protect the most important drainage basin's functions and ecosystems. It is intended that this thesis will serve as an example of the application of current knowledge on freshwater restoration which can be emulated by future managers in their efforts to restore this, or any water body they wish to. To this purpose, the thesis analyzes demographic data on the municipalities of the Tua drainage basin. It discusses literature and research on the subject of river restoration and important river processes in the following chapter, so as to introduce important theory concepts to have in mind when designing any restoration efforts. In its methodology, the techniques and data assessment tools used in the process of evaluating the river basin's conditions are described and defined, allowing interested managers to review and adapt to the specific needs of drainage basins anywhere. Finally, it presents a practical point-of-view intended to be applied on other freshwater bodies. The thesis includes the realization of an assessment physical characteristics and status of the Tua river reach, it splits up the drainage basin into several different sub-basins, for individual study, and, after a discussion of the conclusions drawn from the assessment for the whole drainage basin, it presents arguments for choosing the sub-sections which present the highest risk to the drainage basin and, as such, require priority action. This section also includes a presentation of the arguments in support of specific techniques to be put into place, given the specific needs of the sub-basin and the restoration goals for the entire drainage basin.
Bennett, Jennifer Ann. "Late Pleistocene and Holocene fluvial geomorphology of the River Exe, Devon, UK." Thesis, University of Exeter, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425242.
Full textLi, Bo. "Tidal channel meandering and salt marsh development in a marine transgressed incised valley system the Great Marsh at Lewes, Delaware /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 710 p, 2006. http://proquest.umi.com/pqdweb?did=1208133431&sid=9&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Full textMarston, Bryce Kendrick. "Influence of the Mountain Pine Beetle disturbance on large wood dynamics and channel morphology in mountain streams." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35499.
Full textDepartment of Geography
Charles W. Martin
Disturbance regimes are important determinants of both terrestrial and aquatic ecosystem structure and function. Disturbances may linger in the landscape and lag temporally, influencing stream ecosystem form and function for decades, if not centuries. The recent enhanced Mountain Pine Beetle (MPB) infestation in pine forests of the Rocky Mountain region has resulted in extensive tree mortality, producing the potential for significant increases in carbon supply to stream channels. To better understand MPB impacts on in-stream large wood (LW), a census was conducted in 30 headwater streams within the Medicine Bow National Forest in south-central Wyoming, across the temporal spectrum from early- to late-stage MPB-infestation. A subset of those streams exhibiting mean conditions at each level of infestation was surveyed to determine any significant differences in channel morphology or aquatic ecosystem function. Results indicate that wood loads related to the MPB-infestation significantly increase with time since initial infestation. However, even in late-stage infestation streams, many of the fallen MPB-killed trees are bridging across the channels and have yet to break and ramp down sufficiently enough to enter between the channel margins. Wood loads will continue to increase as more trees fall and bridging pieces decompose, break and then enter the channel. Measurable increases in the amount of LW with time since initial beetle infestation have both positive and negative effects on channel form and function. Although forest MPB-infestation has peaked in the study area, streams are still early on a curve of rapidly increasing wood loads that are beginning to affect streams and have the potential to dramatically increase the carbon base of regional stream ecosystems.
Andrews, William M. "Geologic controls on plio-pleistocene draining evolution of the Kentucky river in central Kentucky." Lexington, Ky. : [University of Kentucky Libraries], 2004. http://lib.uky.edu/ETD/ukygeol2004d00169/wmandrews.pdf.
Full textTitle from document title page (October 12, 2004). Document formatted into pages; contains xi, 216 p. : ill., maps. Includes abstract and vita. Includes bibliographical references (p. 202-212).
Meyers, Matthew Armand. "Fluvial Processes Affecting the Texture of a Gravel Bed with an Emphasis on Salmon Spawning Habitat." Thesis, University of California, Santa Barbara, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10600721.
Full textSpawning salmon depend on fluvial processes to maintain the bed texture of gravel bedded rivers as suitable spawning and incubation habitat. The coarse texture of a gravel bed is maintained by flow strengths capable of moving the gravel and removing fine sediments, thereby providing loose substrate that enhances its ability to conduct flow (i.e., its hydraulic conductivity). The flow strength that corresponds to the beginning of movement (i.e., entrainment) of a grain on a gravel bed is variable and, therefore, it needs to be measured to predict flow levels capable of bed texture maintenance. Lower flows can deliver fine sediment, which may accumulate in the gravels overlying salmon nests (i.e., redds) reducing the hydraulic conductivity and impairing salmon embryo development. I examine these processes to explain the variability in (i) the rate of change in the proportion of a gravel size fraction entrained as a function of flow strength and (ii) the rate of decrease in hydraulic conductivity as a function of the cumulative transport of fine sediment that depends on flow level.
I used tracer gravel and cobble grains and a two dimensional flow model to determine the flow strengths capable of gravel bed entrainment using binary plots of the occurrence or absence of tracer movement to approximate the fraction of the bed sediment entrained as a logistic function of increasing flow strength. The method provides an approximation of the flow strength capable of entraining the least resistant through the most resistant grains, thereby providing a new method to approximate the flow strength that is capable of fully entraining the bed. The results are confirmed by comparing the measurements of two study sites.
To measure the resistance of individual gravel and cobble grains to downstream movement, I used force gages and a theoretical force balance model that incorporates the frictional resistance of a grain and the lift and drag forces applied by stream flow. I measured the frictional resistance of grains at six sites with different morphologies to evaluate influences on grain resistance. Grain resistance varied depending on the grain size and sorting, amount of infiltrated sand, streamwise position along a gravel bar, and degree of fluctuation in the flow strength. The force balance model predicts that the dimensionless instantaneous flow strength capable of entraining a given proportion of a relative grain size varies along a bar. I tested the force balance model predictions by comparison with the tracer measurements from the tracer study. The differences between the force balance predictions and the tracer entrainment measurements are due to the definition of the flow strength as the time-averaged value from the 2D flow model and the instantaneous value from the force balance model. Adjusting the force balance model predictions by a simple factor that quantifies their difference and that corresponds with an index describing the fluctuations of the instantaneous flow strength about its time-averaged value produces agreement with the tracer measurements. This adjustment to force gage measurements from two sites on opposite limbs of a bar indicates that the time-averaged dimensionless flow strength capable of entraining a given proportion of a relative grain size is constant along a bar.
I constructed artificial redds at five sites to monitor changes in hydraulic conductivity and sand accumulation with cumulative bed load transport. I applied two backfill treatments to examine the effects of the presence and absence of grains smaller than 6.4 mm. Hydraulic conductivity varies temporally due to sand deposition and spatially due to the initial sand content of the backfill and the local sediment supply rate. The rate of change in hydraulic conductivity as a function of increasing cumulative transport is statistically significant but does not differ between backfill treatments or with location. I predicted the effect of flow on egg survival using an empirical relationship between hydraulic conductivity and egg survival with results that indicate hydraulic conductivity is dependent on sediment transport rate as a function of flow rate.
This work provides additional understandings of the relationship between flow and bed texture maintenance processes and useful tools for managing gravel bed rivers.
Lo, Edward Limin. "FLUVIAL-LACUSTRINE PROCESSES SHAPING THE LANDFORMS OF THE DISTAL PARAGUAY FLUVIAL MEGAFAN." UKnowledge, 2017. http://uknowledge.uky.edu/ees_etds/54.
Full textFore, Jeffrey D. "Influence of fluvial geomorphology on fish assemblage structure within an agriculturally impacted watershed /." View online, 2008. http://repository.eiu.edu/theses/docs/32211131400070.pdf.
Full textMagirl, Christopher Sean. "Bedrock-controlled Fluvial Geomorphology and the Hydraulics of Rapids on the Colorado River." Diss., The University of Arizona, 2006. http://www.gcmrc.gov/library/reports/physical/Coarse_Sed_Webb/Magirl2006a.pdf.
Full textLiu, Baoli. "Exploring the interaction between rivers and sand dunes : implications for fluvial-aeolian geomorphology." Thesis, University of Hull, 2014. http://hydra.hull.ac.uk/resources/hull:12301.
Full textZancopé, Márcio Henrique de Campos. "Estudo dos padrões de canal fluvial do Rio Mogi Guaçu/SP /." Rio Claro : [s.n.], 2004. http://hdl.handle.net/11449/95622.
Full textBanca: Iandara Alves Mendes
Banca: Cleide Rodrigues
Resumo: O estudo dos padrões de canal fluvial permitiu decifrar as diversas dinâmicas fluviais que o Rio Mogi Guaçu está submetido. A identificação e caracterização dos padrões de canal foram possíveis investigando os parâmetros: largura da planície fluvial, índice de sinuosidade, morfologia do canal, relevo das planícies, largura do canal, profundidade do canal, vazão e velocidade do fluxo. Para o Rio Mogi Guaçu foram encontrados sete padrões: Alto curso; Contato Serra-Depressão; Meandros de Conchal; Meandros de Leme; Boqueirão de Porto Ferreira; Meandros de Jataí; e, Foz do Mogi. A formação destes padrões está ligada a mudanças do gradiente, das estruturas e litologias no perfil longitudinal. Foi possível concluir que o desenvolvimento e a distribuição dos padrões de canal e das planícies fluviais são o resultado do inter-relacionamento das variáveis e fatores do sistema fluvial. Para o Rio Mogi Guaçu estas combinações modificam-se ao longo de todo o curso fluvial condicionando a formação de trechos com distintos padrões e dinâmicas.
Abstract: The study of fluvial channel patterns allowed to decipher various fluvial dynamics that Mogi Guaçu River is submitted. The channel patterns identification and characterization were possible investigating the parameters: floodplain width, sinuosity index, channel morphology, floodplains landform, channel width, channel depth, discharge and flow velocity. For Mogi Guaçu River were met seven channels patterns: Alto curso; Contato Serra-Depressão; Meandros de Conchal; Meandros de Leme; Boqueirão de Porto Ferreira; Meandros de Jataí; e, Foz do Mogi. The formation of these channels patterns is jointed move of gradient, geologic structures and lithologies in the longitudinal profile. It was possible to conclude that the development and the distribution of channel patterns and the floodplains are the effected of the interrelation of the variables and factors system fluvial. For Mogi Guaçu River these combinations modify all along the stream flow conditioning the formation of the intervals with distinct channel patterns and dynamics.
Mestre
Hughes, Michael L. "Channel change of the upper Umatilla River during and between flood periods : variability and ecological implications." Thesis, Connect to title online (ProQuest), 2008. http://proquest.umi.com/pqdweb?did=1678703131&sid=2&Fmt=2&clientId=11238&RQT=309&VName=PQD.
Full textTypescript. Includes vita and abstract. Includes bibliographical references (leaves 124-137). Also available online in ProQuest, free to University of Oregon users.
Clubb, Fiona Jane. "Controls on fluvial networks in upland landscapes : from hillslopes to floodplains." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28817.
Full textCorradini, Fabrício Anibal [UNESP]. "Geomorfologia fluvial, mudanças ambientais e evolução do megaleque do Rio São Lourenço, quaternário do pantanal mato-grossense." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/102881.
Full textConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O megaleque fluvial do São Lourenço é um sistema deposicional que vem sendo construído pelo rio São Lourenço, desde o Pleistoceno, na porção nordeste da bacia sedimentar do Pantanal Mato-Grossense. Com base na interpretação de imagens orbitais e de dados de campo, foram reconhecidos três grandes compartimentos geomorfológicos no megaleque: a) uma extensa planície fluvial pleistocênica dissecada; b) um cinturão de meandros de idade holocênica, ainda ativo nas porções média/superior do megaleque, mas abandonado na sua porção distal; um lobo deposicional moderno composto por vários lóbulos deposicionais. Depósitos de diferentes compartimentos foram amostrados com vibrotestemunhador, sendo as facies sedimentares descritas e interpretadas em termos de processos e de ambientes deposicionais. As idades dos depósitos dos diferentes compartimentos foram obtidas por meio de datação pelo método de luminescência oticamente estimulada (LOE), o que permitiu a proposição de um modelo evolutivo para a área estudada. Na planície aluval dissecada foram reconhecidas paleorredes de canais distributários formados por lobos ativos durante o Pleniglacial médio, entre 64,8 e 28,5 ka AP. A planície aluvial dissecada foi submetida a processos erosivos, existindo na sua superfície uma rede de canais tributários, que drenam as águas das chuvas para as planícies fluviais periféricas dos rios Cuiabá e Piquiri. A maior evidência do evento de dissecação, que do final do Pleistoceno ao Holoceno superior, é a existência de um vale inciso na porção media/superior do megaleque, cortando os depósitos pleistocênicos dos lobos antigos. O vale tem direção N65E, condicionado pela falha de São Lourenço, e nele se encontra alojado o cinturão de meandros formado por agradação fluvial...
The São Lourenço fluvial megafan is a depositional system which has been built by the São Lourenço river since the Pleistocene in the northeastern region of the Pantanal sedimentary basin of Mato-Grosso State. Based on the interpretation of orbital images and collected data field, three major geomorphological compartments of the megafan were recognized: a) an extensive fluvial plain dissected in the Pleistocene; b) a meandering belt of Holocene age, still active in middle and upper parts of the megafan but abandoned in its most distal portion; and c) a modern depositional lobe consisting of several depositional lobes. Deposits of different compartments were sampled with vibrocorer and the recovered sedimentary facies have been described and interpreted in terms of processes and depositional environments. The ages of the deposits of the different compartments were obtained from dating by the optically stimulated luminescence method (OSL), which allowed the proposition of an evolutionary model for the study area. In the dissected alluvial plain, distributary paleochannels were recognized and formed lobes during the active Middle Pleniglacial, between 64,8 and 28,5 ka BP. The dissected alluvial plain was subjected to erosion, identified through the existence on its surface of a tributary drainage network which drains rain water to the peripheral alluvial plains of the Cuiabá and Piquiri rivers. The strongest evidence for dissection of the event, which starts from the late Pleistocene to the Holocene, is the existence of a valley in the middle/upper portion of the megafan, cutting through the Pleistocene deposits of ancient lobes. The valley has a N65E direction, conditioned by the São Lourenço fault, and it is housed in the fluvial meandering belt formed by aggradation of the valley during the Holocene. The heights of the... (Complete abstract click electronic access below)
Finkenbinder, Matthew S. "Development and analysis of lithologically controlled regional curves of hydraulic geometry for Appalachian mountain streams, Ridge and Valley Physiographic Province, Pennsylvania." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5540.
Full textTitle from document title page. Document formatted into pages; contains xii, 219 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 105-108).
Tunnicliffe, Jon Francis. "Holocene sedimentary history of Chilliwack Valley, Northern Cascade Mountains." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/526.
Full textBooker, Douglas James. "Monitoring and modelling sediment transport processes in pool-riffle sequences." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326300.
Full textAtha, Jane. "Fluvial Wood Presence and Dynamics over a Thirty Year Interval in Forested Watersheds." Thesis, University of Oregon, 2013. http://hdl.handle.net/1794/13441.
Full textSantos, Vanessa Cristina dos [UNESP]. "Processos fluviais em barras de soldamento: rio Paraná - PR." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/92770.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O rio Paraná, em seu trecho natural, possui padrão multicanal caracterizado por canais secundários de diferentes ordens, separando diversas ilhas e barras fluviais. As barras fluviais são formas semi-submersas associadas à disponibilidade de sedimentos e a um dinamismo temporal cujas dimensões são controladas pelo fluxo e pela profundidade. Neste estudo, pretende-se compreender os processos que promovem a formação, desenvolvimento e movimentação de uma barra de soldamento situada junto à ilha Santa Rosa, no rio Paraná, município de Porto Rico - PR. Para alcançar os objetivos propostos, foram realizados levantamentos de parâmetros hidráulicos, morfométricos e granulométricos. Nos dados levantados dos parâmetros hidráulicos, verificou-se que a presença da ilha Santa Rosa, juntamente com barra fluvial, divide o canal em dois setores de dinâmica hidráulica e sedimentar distintas. O canal principal conduz a maior parcela da vazão, é mais energético, enquanto o canal secundário apresenta valores inferiores nestes dois parâmetros. A separação do fluxo também acarreta na formação de correntes divergentes à direção principal do canal, favorecendo a diminuição da velocidade e, consequentemente, a deposição de sedimentos no entorno da ilha Santa Rosa. Averiguou-se que a morfologia da barra está diretamente vinculada às flutuações de vazão do rio Paraná: em período de águas altas há maior retrabalhamento da forma, já no período de águas médias, esta se preservou parcialmente, inclusive com afloramento em parte. Quanto aos sedimentos, as partículas de diâmetro fino distribuem-se em locais de maior velocidade de fluxo e profundidade (talvegue) em ambos os períodos analisados As partículas de diâmetro médio a grosso encontram-se no período de águas altas distribuídas pela área estudada; já no período de águas médias, estes sedimentos...
The Paraná River, in its natural stretch, has a multichannel pattern characterized by secondary channels of different orders, which separates several islands and bars. The bars are forms semi-submerged associated with the availability of sediment and a temporal dynamic, whose dimensions are controlled by the flow and depth. This study intends to understand the processes which promote formation, development and movement of the annexation bar associated to the Santa Rosa Island, located on Paraná River, near to Porto Rico - PR. To achieve the proposed aims, surveys were carried out in hydraulic, morphometric and granulometric parameters. In the data hydraulic parameters survey it was found that the presence of Santa Rosa Island along with bar divides the river channel in two sectors of distinct dynamic hydraulic and sediment. The main channel leads to a higher portion of the flow, it is more energetic, while the secondary channel has lower values in these two parameters. The separation of the flow also causes the formation of divergent currents towards the main channel, favoring the decrease in velocity and consequent deposition of sediments near to Santa Rosa Island. It was found that the morphology of the bar is directly linked to fluctuations in the flow of the Paraná River, during periods of high water there is more reworking, since in this average water period partially preserved its shape, emerging in part. As for sediment, the fine diameter particles are distributed in areas of higher flow velocity and depth (thalweg) in both analyzed periods. From medium to coarse diameter particles are, in the high-water period, distributed in the studied area, although in the average water period these sediments are located in low flow velocity and depth (Bar and Secondary Channel). Specific stream power and shields parameter values are larger in the main channel in both periods, indicating... (Complete abstract click electronic access below)
Iwata, Tomoya. "The roles of fluvial geomorphology in the trophic flow from stream to forest ecosystems." 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/86478.
Full textGrudzinski, Bartosz Piotr. "Influence of watershed grazing management on stream geomorphology in grassland headwater streams." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18688.
Full textDepartment of Geography
Melinda D. Daniels
This dissertation increases our understanding of the drivers that shape and maintain grassland streams and their watersheds by examining the influence of grazing management practices on suspended sediment concentrations, bare ground production, and changes to channel geomorphology. Chapter 2 demonstrates that cattle grazing produces significantly higher baseflow suspended sediment concentrations relative to bison grazing. Suspended sediment concentrations within bison-grazed streams are similar to ungrazed streams, indicating that the substitution of cattle for bison has resulted in degradation of baseflow water quality in grassland streams. Burning frequency, discharge, and seasonality are also significant drivers of suspended sediment concentrations, but are generally less influential than grazing treatments. Chapter 3 indicates that high density cattle grazing treatments produce more bare ground within the riparian zones of grassland stream networks, particularly underneath tree canopy cover. The increased bare ground coverage within riparian areas is correlated with increased suspended sediment concentrations during baseflow conditions, while watershed-scale bare ground production is correlated with increased suspended sediment concentrations during storm flow events. Chapter 4 demonstrates channel geometry and sedimentology are significantly influenced by grazing treatments. This dissertation is the first study to comparatively evaluate the relative influence between cattle and bison grazing on stream geomorphology within any environment. Insight gained from this project can be used by public and private land use managers to improve the environmental integrity of native grassland ecosystems.
Zancopé, Márcio Henrique de Campos [UNESP]. "Estudo dos padrões de canal fluvial do Rio Mogi Guaçu/SP." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/95622.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O estudo dos padrões de canal fluvial permitiu decifrar as diversas dinâmicas fluviais que o Rio Mogi Guaçu está submetido. A identificação e caracterização dos padrões de canal foram possíveis investigando os parâmetros: largura da planície fluvial, índice de sinuosidade, morfologia do canal, relevo das planícies, largura do canal, profundidade do canal, vazão e velocidade do fluxo. Para o Rio Mogi Guaçu foram encontrados sete padrões: Alto curso; Contato Serra-Depressão; Meandros de Conchal; Meandros de Leme; Boqueirão de Porto Ferreira; Meandros de Jataí; e, Foz do Mogi. A formação destes padrões está ligada a mudanças do gradiente, das estruturas e litologias no perfil longitudinal. Foi possível concluir que o desenvolvimento e a distribuição dos padrões de canal e das planícies fluviais são o resultado do inter-relacionamento das variáveis e fatores do sistema fluvial. Para o Rio Mogi Guaçu estas combinações modificam-se ao longo de todo o curso fluvial condicionando a formação de trechos com distintos padrões e dinâmicas.
The study of fluvial channel patterns allowed to decipher various fluvial dynamics that Mogi Guaçu River is submitted. The channel patterns identification and characterization were possible investigating the parameters: floodplain width, sinuosity index, channel morphology, floodplains landform, channel width, channel depth, discharge and flow velocity. For Mogi Guaçu River were met seven channels patterns: Alto curso; Contato Serra-Depressão; Meandros de Conchal; Meandros de Leme; Boqueirão de Porto Ferreira; Meandros de Jataí; e, Foz do Mogi. The formation of these channels patterns is jointed move of gradient, geologic structures and lithologies in the longitudinal profile. It was possible to conclude that the development and the distribution of channel patterns and the floodplains are the effected of the interrelation of the variables and factors system fluvial. For Mogi Guaçu River these combinations modify all along the stream flow conditioning the formation of the intervals with distinct channel patterns and dynamics.
Corradini, Fabrício Anibal. "Geomorfologia fluvial, mudanças ambientais e evolução do megaleque do Rio São Lourenço, quaternário do pantanal mato-grossense /." Rio Claro : [s.n.], 2011. http://hdl.handle.net/11449/102881.
Full textBanca: José Cândido Stevaux
Banca: Edvard Elias de Souza Filho
Banca: Archimedes Perez Filho
Banca: Cenira Maria Lupinacci da Cunha
Resumo: O megaleque fluvial do São Lourenço é um sistema deposicional que vem sendo construído pelo rio São Lourenço, desde o Pleistoceno, na porção nordeste da bacia sedimentar do Pantanal Mato-Grossense. Com base na interpretação de imagens orbitais e de dados de campo, foram reconhecidos três grandes compartimentos geomorfológicos no megaleque: a) uma extensa planície fluvial pleistocênica dissecada; b) um cinturão de meandros de idade holocênica, ainda ativo nas porções média/superior do megaleque, mas abandonado na sua porção distal; um lobo deposicional moderno composto por vários lóbulos deposicionais. Depósitos de diferentes compartimentos foram amostrados com vibrotestemunhador, sendo as facies sedimentares descritas e interpretadas em termos de processos e de ambientes deposicionais. As idades dos depósitos dos diferentes compartimentos foram obtidas por meio de datação pelo método de luminescência oticamente estimulada (LOE), o que permitiu a proposição de um modelo evolutivo para a área estudada. Na planície aluval dissecada foram reconhecidas paleorredes de canais distributários formados por lobos ativos durante o Pleniglacial médio, entre 64,8 e 28,5 ka AP. A planície aluvial dissecada foi submetida a processos erosivos, existindo na sua superfície uma rede de canais tributários, que drenam as águas das chuvas para as planícies fluviais periféricas dos rios Cuiabá e Piquiri. A maior evidência do evento de dissecação, que do final do Pleistoceno ao Holoceno superior, é a existência de um vale inciso na porção media/superior do megaleque, cortando os depósitos pleistocênicos dos lobos antigos. O vale tem direção N65E, condicionado pela falha de São Lourenço, e nele se encontra alojado o cinturão de meandros formado por agradação fluvial... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The São Lourenço fluvial megafan is a depositional system which has been built by the São Lourenço river since the Pleistocene in the northeastern region of the Pantanal sedimentary basin of Mato-Grosso State. Based on the interpretation of orbital images and collected data field, three major geomorphological compartments of the megafan were recognized: a) an extensive fluvial plain dissected in the Pleistocene; b) a meandering belt of Holocene age, still active in middle and upper parts of the megafan but abandoned in its most distal portion; and c) a modern depositional lobe consisting of several depositional lobes. Deposits of different compartments were sampled with vibrocorer and the recovered sedimentary facies have been described and interpreted in terms of processes and depositional environments. The ages of the deposits of the different compartments were obtained from dating by the optically stimulated luminescence method (OSL), which allowed the proposition of an evolutionary model for the study area. In the dissected alluvial plain, distributary paleochannels were recognized and formed lobes during the active Middle Pleniglacial, between 64,8 and 28,5 ka BP. The dissected alluvial plain was subjected to erosion, identified through the existence on its surface of a tributary drainage network which drains rain water to the peripheral alluvial plains of the Cuiabá and Piquiri rivers. The strongest evidence for dissection of the event, which starts from the late Pleistocene to the Holocene, is the existence of a valley in the middle/upper portion of the megafan, cutting through the Pleistocene deposits of ancient lobes. The valley has a N65E direction, conditioned by the São Lourenço fault, and it is housed in the fluvial meandering belt formed by aggradation of the valley during the Holocene. The heights of the... (Complete abstract click electronic access below)
Doutor
Silva, Juliana de Paula. "Avaliação da diversidade de padrões de canais fluviais e da geodiversidade na Amazônia - aplicação e discussão na bacia hidrográfica do Rio Xingu." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-22022013-104907/.
Full textThe study of geodiversity has been developed since the 1990s and aims the knowledge, description and conservation of natural heritage, through the evaluation of geological (minerals, rocks and fossils), geomorphological (landforms, processes) and pedological aspects. This research has intended to demonstrate and evaluate the potential use of fluvial geomorphological variables as geodiversity indicators, in view of the underutilization of this kind of indicator in environmental studies in Brazil. This underutilization is a critical issue for the Amazon region, where fluvial environments have great relevance on diverse aspects (environmental, cultural, aesthetic and scientific). The central aim of the thesis is the morphological characterization and analysis of river channel patterns and other parameters of fluvial morphology in sampling areas in the Xingu River Basin, in order to demonstrate the relevance of these parameters for the assessment of geodiversity in the Amazon. Although still largely preserved by conservation units and indigenous lands, the Xingu Basin suffers severe anthropogenic pressures, mainly caused by soy monocultures in headwater areas and by the construction of the Belo Monte Dam in the \"Volta Grande do Xingu\", near the town of Altamira, in the state of Pará. This research was conducted at two different spatial scales. On a more detailed scale (1:150,000), maps of fluvial morphology were made for 23 selected areas, which were considered representative of the diversity of river channel patterns in the drainage basin. This characterization proved the great diversity of river channel patterns in the study area, demonstrating the relevance of this parameter as an indicator of geodiversity. Such a characterization was also useful as a basis for the inclusion of the variable \"change in channel pattern\" in the mapping methodology of the geodiversity indexes in the Xingu Drainage Basin. On a less detailed scale, a method to quantify the geodiversity was applied to the entire drainage basin, based on the measurement and integration of abiotic elements, spatially distributed on thematic maps with scales ranging from 1:250,000 to 1:1,000,000, with the aid of a systematic articulation grid 1:25,000. On this scale it was also performed a correlation between the geodiversity and the biodiversity indexes, the latter inferred by vegetation mapping on scale 1:250,000 (IBGE, 2000c). XIII The main contributions of this research are the enrichment of the knowledge basis about large Amazonian rivers, as well as the application of a method for mapping the geodiversity indexes, which can be useful as a tool for environmental planning, particularly in defining priority areas for conservation in the Amazon region.
Ewald, Karl Heins. "Caracterização de formas topográficas em fundos de vale no Planalto de Cascavel, Região Oeste do Estado do Paraná." Universidade Estadual do Oeste do Paraná, 2013. http://tede.unioeste.br:8080/tede/handle/tede/1655.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior
Rivers are important agents working in the sculpturing of relief, through its high transport capacity of sediments originary from slopes and marginal erosion. The modeling occurs through the processes of erosion and deposition of sediments, which depend on variables such as lithological composition, slope, and flooding. The processes that originate topographic forms are widely described in the literature of alluvial-bed rivers, however little is known about the occurrence of these forms in mixed bed channels (alluvial-rock) and bedrock channel. In this context, this research aims to describe the topographic forms of the valleys on the Cascavel Plateau. The method for the recognition of these forms is the topographic mapping of cross sections in different parts of the channel located at the top, middle and lower course. The mapping is performed with a set level and optical sights. Were mapped four fluvial channels, two channels in areas with altimetric elevations below 400 meters, and two other channels with elevations above 700 meters. The channels have floodplains with varying lengths. Topographic forms were found as dikes, point bars, flood inundation basins, pools and riffles. The data collected show strong channel incision in the sections corresponding to the upper parts of the channels, and that in the course stretches of low flood plains are well developed. Channel meandering is a characteristic feature of the Cascavel Plateau. The formation of point bars is directly associated with the channel marginal erosion, whereas the dikes are the result of sediment settling. The pool-riffle sequences occur by the reduction of the flow velocity in some places, and, in others, by the presence of woody debris. In some parts of the river where are rock outcrop was observed the formation of pot-holes
Os rios são importantes agentes atuando na esculturação do relevo por meio da sua alta capacidade de transporte de sedimentos originários das vertentes e dos processos de erosão marginal. A modelagem ocorre através dos processos de erosão e deposição de sedimentos, que dependem de variáveis como composição litológica, declividade e cheias. Os processos que originam as formas topográficas são descritos vastamente na literatura sobre rios de leito aluviais, no entanto pouco se sabe sobre a ocorrência dessas formas em canais de leitos mistos (aluviais-rochosos) e leitos rochosos. Nesse contexto esta pesquisa objetiva a descrição das formas topográficas de fundos de vale no Planalto de Cascavel. O método para o reconhecimento dessas formas topográficas consiste no mapeamento de seções transversais em trechos distintos do canal localizados no alto, médio e baixo curso. O mapeamento é realizado com um conjunto de nível ótico e mira. Foram mapeados quatro canais fluviais, sendo dois canais em áreas com cotas altimétricas inferiores a 400 metros e, outros dois canais com cotas superiores a 700 metros. Os canais apresentam planícies de inundação com extensões variadas. Foram encontradas formas topográficas como diques, barras em pontal, bacias de inundação, soleiras e depressões. Os dados coletados mostram que há forte incisão do canal nos trechos correspondentes ao alto curso dos canais, e, que nos trechos de baixo curso as planícies de inundação são bem desenvolvidas. O meandramento de canais é uma característica do Planalto de Cascavel. A formação de barras em pontal está associada diretamente a erosão marginal, enquanto que os diques são resultantes da decantação de sedimentos. As sequências de soleiras-depressões ocorrem pela diminuição da velocidade do fluxo em alguns trechos, e, em outros, pela presença de detritos lenhosos. Nos trechos rochosos onde há afloramento rochoso foi observada a formação de marmitas
Delaney, Adam J. "Effects of climate and development on the hydrology and geomorphology of the Yellow Creek Watershed, Summit and Medina Counties, OH." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1479127682219327.
Full textEvans, Lisa J., and n/a. "The Influence of fluvial geomorphology on riparian vegetation in upland river valleys: south eastern Australia." University of Canberra. School of Resources Environmental and Heritage Sciences, 2003. http://erl.canberra.edu.au./public/adt-AUC20050404.112525.
Full textVillacorta, Sandra, and José Ubeda. "The Geomorphic Map of Metropolitan Lima and its Hidrographic Basins, a Tool to the Sustainable Land Management." Pontificia Universidad Católica del Perú. Centro de Investigación en Geografía Aplicada, 2013. http://repositorio.pucp.edu.pe/index/handle/123456789/119851.
Full textEn este trabajo se presenta una iniciativa conjunta del Instituto Geológico Minero y Metalúrgico (Ingemmet) y el Grupo de Investigación en Geografía Física de Alta Montaña de la Univeridad Complutense de Madrid (GFAM-UCM) para promover en el Perú las investigaciones sobre geomorfología y cambio climático. El plan consiste en elaborar mapas geomorfológicos de la región de Lima Metropolitana y las cabeceras de sus cuencas hidrográficas (Chillón, Luríny Rímac) generando instrumentos de análisis para: 1) Decodificar el registro de los cambios climáticos en las formas del relieve. 2) Delimitar las reservas hídricas almacenadas en forma de masas de hielo (criosfera), conocer sus tendencias y elaborar pronósticos de futuro. 3) Identificar las relaciones entre las geoformas del relieve y los peligros geológicos que afectan a la población y sus actividades económicas. 4) Diseñar una metodología que pueda extrapolarse a otras regiones peruanas. Con el fin de lograr esos objetivos, en primer lugar se van a elaborar mapas geomorfológicos integrados en sistemas de información geográfica (SIG): se diferenciarán las unidades morfoclimáticas, se identificarán los procesos que las generaron y se propondrán sus cronologías relativas. A continuación, se establecerán las cronologías absolutas de unidades clave, que permitirán confirmar o corregir la anterior secuencia de edades. De este modo se desea contribuir a desarrollar modelos de la evolución del clima, colaborar con la evaluación de los peligros geológicos y conocer el estado de la criosfera, incluyendo tendencias pasadas y previsiones futuras.
Nesheim, Andrew Olaf. "Predicting bed grain size in Maine rivers using lidar topographic data." Thesis, Boston College, 2011. http://hdl.handle.net/2345/2364.
Full textRiver channel morphology in northern New England depends on channel position relative to glacial geomorphology and history. This thesis considers three paraglacial Maine rivers: the West Branch of the Pleasant River (WBPR), a steep inland imposed-form tributary of the Piscataquis River, and the Narraguagus and Sheepscot rivers, two coastal low-gradient rivers. I use a simple model based on the Shields and Manning equations to predict median bed grain size in these recently deglaciated watersheds. The main objectives of this study are to: (1) understand how bedrock controls on the longitudinal profile and sediment inputs impact substrate grain size and channel morphology in the WBPR; (2) apply a model predicting substrate grain size based on digital elevation model (DEM)-derived geometric channel parameters; (3) compare the results from the high gradient WBPR to previously studied low-gradient coastal Maine rivers; and (4) explore the implications of my findings on channel and habitat restoration in paraglacial rivers. I use standard and lidar (light detection and ranging) digital elevation models (DEMs) and spatial analyses to measure channel parameters necessary to predict bed grain size and compare them to field measurements. Predicted bed grain size falls within a factor of two of the field-measured median in ~70% of the study sites. The model performs best in supply-limited alluvial single-thread channel segments with gravel-cobble lag deposit beds, and is less successful in transport-limited depositional segments with relatively fine beds and greater channel variability. Channel segments that are transitional between these two cases (intermediate channel complexity and grain size) are associated with intermediate grain size prediction accuracy. Model failures occur in segments that deviate from the single-thread gravel-bed channel type, and may indicate areas to focus restoration efforts. This study builds on previous research on low-gradient coastal rivers in Maine, and has wide application to future research or restoration projects concerned with sediment mobilization and fluvial ecology
Thesis (MS) — Boston College, 2011
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Geology and Geophysics
Afolabi, Olamide. "Quantitative characterisation of channel sinuosity, determination of catchment and sedimentary basin controls on channel sinuosity and interpretation of channel planform in fluvial systems with GIS and remote sensing techniques." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=226793.
Full textShintani, Christina. "Comparing Photogrammetric and Spectral Depth Techniques in Extracting Bathymetric Data from a Gravel-Bed River." Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20517.
Full textLuz, Rodolfo Alves da. "Geomorfologia da planície fluvial do rio Pinheiros entre os bairros de Pinheiros, Butantã e Cidade Jardim, São Paulo (SP)." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-03112010-093445/.
Full textThis research investigates the geomorphology of part of Pinheiros River fluvial plain in São Paulo city. This study main result is a detailed geomorphologic map - 1:20,000 - that used ancient aerial photographs and maps obtained from formal archival surveys. The descriptions of floodplain units were associated to stratigraphic and sedimentologic data obtained from recent engineering projects reports of São Paulo underground (such as subway). This association allows the understanding of part of Pinheiros River fluvial system and morphodynamic before urbanization. The research also allowed offering a sequence of geomorphological events related to the floodplain and channel systems over the Holocene. Morphometric parameters, such as width and sinuosity index of channels and paleo-channels of floodplain meandering system, appear as an evidence of the structural influence in geomorphological evolution of this system. The recognition of geomorphologic systems in pre-disturbance stage is essential for understanding the current processes, mainly in environments greatly modified by human actions, such as urban areas. This research presents this kind of recognition and contributes to the understanding of processes in the system before human actions in the surface.
Wallerstein, Nicholas Paul. "Impact of Large Woody Debris on fluvial processes and channel geomorphology in unstable sand-bed rivers." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311841.
Full textKent, Emiko Jane. "The relationship between active faulting and fluvial geomorphology : a case study in the Gediz Graben, Turkey." Thesis, University of Plymouth, 2015. http://hdl.handle.net/10026.1/4253.
Full textPhillips, Zachary Rockford. "Holocene Postglacial Fluvial Processes and Landforms in Low Relief Landscapes." Diss., North Dakota State University, 2020. https://hdl.handle.net/10365/32036.
Full textNorth Dakota Water Recourses Research Institute (ND WRRI) Fellowship Program
Zancope, Marcio Henrique de Campos. "Analise morfodinamica do Rio Mogi Guaçu." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287362.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias
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Resumo: Este estudo mostra que a dinâmica fluvial do Rio Mogi Guaçu (NE do Estado de São Paulo, SE Brasileiro) é influenciada pelas estruturas geológicas da bacia hidrográfica e pelas litologias que sustentam o leito fluvial. Essas estruturas e litologias afetam a forma do perfil longitudinal, alterando as relações entre a dinâmica da corrente fluvial e a carga sedimentar, seccionando o curso d'água em trechos com diferentes condições de transporte e morfologia do canal. A análise do perfil longitudinal do Vale e do Rio Mogi Guaçu permitiu correlacionar as estruturas geológicas e a distribuição da litologia com as anomalias na forma do perfil. Estas anomalias são setores do curso fluvial situados acima ou abaixo da linha de tendência do perfil longitudinal. Litologias resistentes à erosão fluvial sustentam anomalias acima da linha de tendência do perfil, enquanto que estruturas e lineamentos orientaram movimentos neotectônicos quaternários, promovendo anomalias abaixo da linha de tendência. A análise do desenvolvimento dos meandramentos e a associação de pedofácies mostraram duas planícies do Rio Mogi Guaçu com comportamentos morfodinâmicos distintos. A primeira delas, situada a montante de uma anomalia da forma do perfil longitudinal, mostrou processos de migração dos meandros concentrados exclusivamente no cinturão meândrico e solos com maturidade mínima e intermediária. A segunda, situada a jusante de outra anomalia, mostrou processos de migração dos meandros dispersos por toda a planície aluvial e solos com maturidade mínima. As estruturas geológicas e litologias promovem as anomalias na forma do perfil longitudinal do Rio Mogi Guaçu por meio de mudanças no gradiente fluvial, formando setores com comportamentos morfodinâmicos diferentes.
Abstract: This study shows that fluvial dynamics of the Mogi Guaçu River (NE State of São Paulo, SE Brazilian) is influenced by hydrographic basin geological structures and lithologies that sustain the river bed. These structures and lithologies affect the shape of the longitudinal profile, changing the relationships between the stream flow dynamics and sedimentary load, breaking the river into segments with different transport conditions and morphology of the channel. Longitudinal profile analysis of the Mogi Guaçu Valley and River allowed to correlate the geological structures and distribution of lithology with the anomalies in the shape of the profile. These anomalies are segments of the river located above or below the trend line of the longitudinal profile. Lithologies resistant to fluvial erosion sustain anomalies above trend line of the profile, while structures and lineaments oriented Quaternary neotectonics motions, promoting anomalies below the trend line. Meandering development analysis and pedofacies association showed two floodplains of Mogi Guaçu River with different mophodynamics behaviors. The first of them, upstream an anomaly in the shape of the profile, showed meanders migration processes concentrated exclusively in the meander belt and soils with minimum and intermediate maturity. The second, downstream another anomaly in the shape of the profile, showed meanders migration processes for the whole floodplain and soils with minimum maturity. The geological structures and lithologies promote the anomalies in the shape of the longitudinal profile of the Mogi Guaçu River through changes in the fluvial gradient, forming segments with different mophodynamics behaviors.
Doutorado
Análise Ambiental e Dinâmica Territorial
Doutor em Ciências
Arey, Jordan Vincent. "Stratigraphy and Soils of Fluvial Terraces on the Catawba River, NC and SC| Landscape Evolution of the Southeastern US." Thesis, The University of North Carolina at Charlotte, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10814283.
Full textFew studies provide data that can document the long-term landscape evolution of the Piedmont of the southeastern United States. Here we present the results of field mapping and a soil chronosequence for fluvial terraces along a ~46 km reach of the Catawba River, NC and SC. Five terrace units (Qt1–5) have been mapped along the reach, and in certain regions a sixth surface (Qt0) was mapped. Observations of bedrock surfaces on Qt3–Qt0 confirmed that these units are strath terraces. Longitudinal profiles of terrace units constructed from mapping data revealed static channel convexities in Qt5–Qt1 in the lower reach of the study area at Landsford Canal State Park, and a lack of an obvious influence on terraces profiles within the Gold and Silver Hill shear zones in the middle reach. Age dating of terraces in this study included deriving ages based on surface height above the channel (Mills, 2000) and IRSL samples obtained from Qt3 exposures. Ages, reported in ka, are as follows: Qt0—4591 ± 404 ka, Qt1—1852 ± 365 ka, Qt2—1181 ± 194 ka, Qt3 (average of two IRSL ages)—142 ± 32 ka, Qt4—50 ± 8 ka, and Qt5—5 ± 2 ka. Up to 3 soil pits were dug on each terrace unit Qt5—Qt2, and soils described as per Birkeland (1999). Chronofunction trends of soil morphological properties include soil colors in the most developed B horizons reddening and clay films increasing in amount and prominence with surface age. Soil samples were analyzed for particle size, pedogenic iron (AAS), bulk density and major elements (XRF). Some of these analyses show expected trends with respect increasing surface age for terraces of the Catawba River, such as increases in clay content (%) and decreases in iron activity ratios in most weathered B horizons with increasing surface age. Overall the history Catawba River is one of five distinct periods of lateral planation of the valley, possibly driven by transitions to interglacial periods, punctuated by periods of incision, whose cause is currently unknown. The soil chronosequence, ages, and data derived from mapping, however, provide a strong foundation that can be used in further studies of the long-term landscape evolution of the SE Piedmont of the SE United States.
Boaz, Lindsey E. "Influences of fluvial geomorphology on aquatic-to-terrestrial Hg transport: evidence from protected and urban streams of central Ohio, USA." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1420822467.
Full textMercurio, Matthew Forrest. "Divider analysis of drainage divides delineated at the field scale." Virtual Press, 2004. http://liblink.bsu.edu/uhtbin/catkey/1306855.
Full textDepartment of Geology
Wilkins, Benjamin Carleton. "Geomorphic comparison of two Atlantic coastal rivers: toward an understanding of physical controls on Atlantic salmon habitat." Thesis, Boston College, 2009. http://hdl.handle.net/2345/674.
Full textSubstrate size and mobility are important to Atlantic salmon (Salmo salar) spawning and rearing success. Channel geometry is a control on bedload mobility in streams. It is believed that channel morphology in many Maine rivers has been altered by land use practices, creating wider and shallower channels, and lowering stream competence. If correct, these changes may be partially responsible for the limited number of returning salmon currently observed in Maine coastal rivers. To evaluate the magnitude of these changes, I performed a statistical comparison of channel morphology between two Atlantic coastal streams: the Narraguagus River in Downeast Maine and the Jacquet River in northern New Brunswick, Canada. Compared to the Narraguagus River, the Jacquet River has relatively healthy returns of adult salmon. Both watersheds have similar drainage areas (Narraguagus 588 km²; Jacquet 510 km²;) and mean annual precipitation (1244 mm; 1200 mm), but differing average channel gradients (0.16%; 0.51%) and longitudinal profiles. During the summer of 2007, I surveyed a 13.6-km section of the Narraguagus with a drainage area range of 129-247 km², and a 10.4-km section of the Jacquet with a drainage area range of 94-265 km². I made measurements of active and bankfull width and depth, and channel gradient at 100-m intervals, and performed grain-size counts at 200-m intervals. I also measured gradient and width in a GIS-based analysis. Results of my analysis show that channel gradient is likely the most influential factor on Atlantic salmon habitat as it relates to sediment size. The two rivers exhibit no significant difference in width-to-depth ratio, when low-gradient outliers in the Narraguagus River are removed. Predicted median riverbed grain sizes were calculated using two methods: (1) from the empirical relationship between basal shear stress and measured grain size; and (2) using the Shields parameter and remote sensing data only. Measured and predicted grain sizes reveal finer river-bed sediments on the Narraguagus River, however, Shields parameter calculations show that sediment should be mobile in both streams. I compare these predictions to field-based habitat mapping on the Narraguagus River. Based on predicted grain sizes, I expect nearly continuous Atlantic salmon spawning (28-95%) and rearing (95-100%) habitat on the Jacquet, and much less spawning (47-62%) and rearing (57-68%) habitat on the Narraguagus. This is likely because the Narraguagus River is segmented into reaches of steeper gradient (S < 0.002) with potentially good habitat, and flatter reaches (S < 0.0005) of poor habitat. The long flat reaches (several km) likely act as sediment sinks, preventing the continuity of downstream sediment transport and causing sediment to be sourced from localized glacial deposits
Thesis (MS) — Boston College, 2009
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Geology and Geophysics