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Holowaty, Nadja Deyglun. "Floodplain management in Quebec : a case study of the Mille Iles River floodplains." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63232.
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Wolfe, Brian Paul. "Floodplains and the Proximate Principle: A Case for Floodplain Linear Parks in Roanoke, Virginia." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/33151.
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The intention of this paper is to argue a position for the use of floodplain linear parks as a means of urban flood mitigation. Current approaches often focus on protecting existing and future structures via the use of costly-engineered solutions such as dams and floodwalls. My argument is that the same money can be used to restore the floodplain by removing such structures and establishing a park system that will serve as a valuable public amenity, while allowing flooding to occur with minimal damage produced. In the long run, such a park will provide a greater return on the investment than other potential solutions. A discussion of the â Proximate Principleâ will describe how this works. From an environmental perspective, the importance of such a park will be discussed by placing it in the context of the green infrastructure concept, which is essentially an umbrella term for ongoing efforts to better integrate human and natural systems. Three case studies are presented that demonstrate examples of such park systems and the effects they had on local economies and communities. These studies begin demonstrating the social connotations for such a project as well. Throughout this paper, ties are made to the city of Roanoke, Virginia (where the project portion of this thesis takes place) to demonstrate the relevance of floodplain linear parks to the city. All arguments made are supported by a conceptual floodplain park plan for the city of Roanoke.Master of Landscape Architecture
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Sims, Neil C., and n/a. "The landscape-scale structure and functioning of floodplains." University of Canberra. Resource, Environmental & Heritage Sciences, 2004. http://erl.canberra.edu.au./public/adt-AUC20050706.095439.
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Floodplains are amongst the most productive and biodiverse ecosystems. The structure and functioning of floodplains is controlled by the interaction of intermittent inundation with the floodplain landscape. These interactions create highly complex and dynamic ecosystems that are difficult to study at large scales. Consequently, most research of floodplains has been conducted at small spatial and temporal scales. Inundation of floodplains can extend over many square kilometres, however, which unifies the floodplain landscape into an integrated ecosystem operating at the landscape scale. The lack of data and poor understanding of the landscape-scale structure and functioning of floodplains limits the possibility of managing floodplains sustainably as pressure for exploitation of their resources increases. This thesis quantifies the landscape-scale relationship between the frequency and patterns of inundation, the composition and structure of the landscape, and the functioning of the floodplain landscape in terms of the distribution and dynamics of plant growth vigour over an area of approximately 376,000 ha on the Lower Balonne Floodplain; highly biodiverse, semi-arid floodplain ecosystem that straddles the state border between New South Wales and Queensland approximately 500 km inland from the eastern coast of Australia. Mean annual rainfall at St.George, to the north of the study area, is approximately 400�450 mm per year, and median annual evaporation is approximately 2000 mm per year. Plants and animals on the floodplain are therefore heavily dependent upon flooding for survival. This project is based on the analysis of 13 Landsat Thematic Mapper satellite images captured over a 10-year period during which land and water resource development increased substantially. There is now concern that development activities have affected the functioning of the floodplain to the detriment of the natural environment and
agricultural productivity. The impacts from these activities on the functioning of the floodplain are not yet known, however. Inundation of the Lower Balonne Floodplain was mapped using a two-part process involving a band ratio to identify deep clear water, and a change detection analysis to identify areas of shallower inundation. This analysis shows that, in contrast with most floodplains, the main flowpath of the Lower Balonne Floodplain runs along its central axis away from river channels, which flow along the floodplain�s outer edges. Inundation propagates from the centre of the floodplain out towards river channels as flood discharge volumes increase. Variations in the spatial pattern of inundated patches within the inundated extent create distinctive aquatic habitat and connectivity conditions at different flow levels. These can be described in terms of three connectivity phases: (I) Disconnected, in which isolated patches of inundation occur at low flows and river channels are hydrologically dislocated from the floodplain; (II) Interaction, where increased hydrological connectivity between inundated patches, and between the floodplain and the river channels at moderate flows, may enable significant exchange of materials, organisms and energy; and (III) Integration, in which almost the entire floodplain landscape is connected by open water during large magnitude floods. There is an abrupt transition in inundation patterns as flows increase between 60,000 ML day-1 and 65,000 ML day-1 (ARI 2 to 2.3 years) in which inundation patterns transform from being relatively disconnected into a highly integrated network of patches. These patterns may have significant consequences for the structure and functioning of the floodplain. Increases in flows across this small range may therefore mark an important ecological flow threshold on this system. Water resource development impacts have changed the relative frequency of flows on the Lower
Balonne Floodplain, which will probably affect the sequence of connectivity phases over time. The most likely impact of these changes will be to create a floodplain that is drier overall than under natural flow conditions, and that has a smaller and wetter area of high inundation frequency. The relationship between inundation and the structure of the floodplain landscape was examined by comparing a landcover map showing the distribution and character of 10 landcover types to the inundation frequency maps. Landcover types were mapped from a multi-date Reference Image composite of seven images captured over a period of 10 years. The Reference Image improves landcover discrimination by at least 14% over classification of a single-date image, and has an overall accuracy between 82.5% and 85% at the landscape-scale. The Reference Image shows that the landscape of the Lower Balonne Floodplain is a highly fragmented mosaic of diverse landcover types distributed in association with inundation frequency. Stratifying the floodplain into zones of frequent and rare inundation shows that frequently inundated areas have a less fragmented but less diverse landscape structure than rarely inundated areas. Assessment of the functioning of each landcover types within the floodplain ecosystem, based on landscape pattern metric analysis, indicates that the function of landcover types also changes between inundation frequency zones. Most importantly, these changes include a transformation of the matrix landcover type, which controls the character and dynamics of the ecosystem overall, from Open Grassland to Coolibah Open Woodland in the frequently inundated zone. The landscape structure of the Lower Balonne Floodplain has been affected by development impacts, which include clearing of native vegetation, isolation of parts of the floodplain from natural inundation events by the construction of levee banks and drainage channels, and grazing impacts. Changes to the inundation regime may also
affect the structure of the floodplain landscape. Over the long term, these changes are likely to create a larger area of Open Grassland and a smaller area of Coolibah Open Woodland as the zone of frequent inundation becomes smaller and wetter. To examine the functioning of the floodplain ecosystem, the inundation maps were compared to remotely sensed indexes of plant growth vigour at the landscape and landcover-type scales. The dynamics of plant growth vigour over time are influenced by factors operating at the regional, landscape and patch scales. Evaporation is the major control of growth vigour levels at the landscape scale, but each landcover type has a distinctive pattern of growth vigour dynamics that is related to its composition and location, and possibly its landscape structure. The association between the spatial distribution of plant growth vigour and inundation frequency is non-linear, with the highest growth vigour occurring where inundation occurs approximately once per year. This indicates a subsidy-stress interaction with water in which plant growth vigour is limited by soil anoxia in areas of frequent or long term inundation, and by drought stress in rarely inundated areas. A landscape-scale model of growth vigour dynamics, founded on the principles of Hierarchical Patch Dynamics and Landscape Ecology, was created from growth vigour measurements of each landcover type over time. This model was used to examine possible impacts of development activities on the functioning of the floodplain ecosystem. This model shows that the response of plant growth vigour development activities can be complex and subtle, and include a change in mean long-term growth vigour and an increased susceptibility to drought. The model also indicates that periods of high growth vigour can occur in substantially altered floodplain ecosystems. The model was also used to explore the levels of landcover change that might cause a threshold change in the functioning of the ecosystem, which may substantially alter the
disturbance-response characteristics of the floodplain ecosystem. The model indicates a threshold change when the extent of Open Grassland is reduced by 30% of its extent in 1993, in which plant growth vigour response to disturbance is virtually inverted from that observed in the images. The temporal variability of plant growth vigour levels increases as the extent of Open Grassland is further reduced. This thesis makes a number of important contributions to our understanding of floodplain structure and functioning. It includes the development of new techniques suited to studying large diverse and complex landscapes at the landscape scale from satellite images, and provides quantitative data describing the links between the structure of floodplain landscapes and their functioning at the landscape scale. This work improves the understanding of floodplain ecosystems by integrating models of floodplain structure and functioning, which have been developed largely from smaller-scale studies of temperate and tropical floodplains, with landscape-scale measurements of this semi-arid system. This thesis also has implications for the Lower Balonne Floodplain by improving the level of information about this important ecosystem and providing baseline data against which the condition of the floodplain can be assessed in future.
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Natho, Stephanie. "Modelling nutrient retention in floodplains." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2013. http://dx.doi.org/10.18452/16854.
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Obwohl es sehr detaillierte Studien zur Nährstoffretention in einzelnen Auen und Feuchtgebieten gibt, ist die Bedeutung von Auen für die Nährstoffbilanz auf Landschaftsebene wenig untersucht. Dies liegt an dem geringen Wissensstand über die wichtigsten Parameter der Nährstoffretention, nämlich die überflutete Auenfläche sowie die in die Aue strömende Nährstofffracht. Zusätzlich gibt es bislang keinen Ansatz, demzufolge beide Parameter abhängig vom Abfluss, und damit variabel für verschiedene zeitliche Einheiten, berechnet werden können. Aus diesem Grund analysiert diese Arbeit die Überflutungshäufigkeiten der Auen von drei Flüssen, Elbe, Main und Rhein. Darauf aufbauend wird eine Abhängigkeit zwischen der überfluteten Fläche und dem Abfluss empirisch abgeleitet, die auf detaillierten Berechnungen der etablierten Software Flys basieren. Ausgehend auf diesen im Folgenden generalisierten Ergebnissen werden eine letztendlich Ereignis basierte mittlere überflutete Auenfläche sowie einströmende Nährstofffracht abhängig vom jeweiligen Abfluss berechnet. Diese und weitere Geoinformationsdaten wie auch Pegel und Gütedaten finden Eingang in jährliche und monatliche empirische Retentionsmodelle. Die berechnete Nährstoffretention in den Auen ist abhängig von der hydrologischen Konnektivität der Auen und dem tatsächlichen Abfluss. Deshalb wird letztendlich das weiterentwickelte Konzept der Ereignis bezogenen Nährstoffretention angewendet und als am realistischsten in Kombination mit hydro-exponentiellen Retentionsmodellen erachtet. Für die naturnahe Elbe werden in Monaten mit Hochwässern bis zu 9% bzw. 10% Retention der transportierten TP bzw. der NO3-N Fracht berechnet. Die Übertragbarkeit dieser Ergebnisse auf eine deutschlandweite Kulisse ist durch die generalisierten Methoden geschaffen. Die vorliegende Arbeit leistet damit einen Beitrag, die Bedeutung der Auen für die Nährstoffbilanz auf Landschaftsebene abhängig von hydrologischen Gegebenheiten zu quantifizieren.Although there are detailed studies on nutrient retention in single wetlands and floodplains, the role of riparian floodplains for nutrient retention is not investigated very well on a landscape scale, since knowledge on the most important parameters for nutrient retention, inundated floodplains and incoming load, is insufficient. Additionally, a method for describing these parameters as discharge dependent variables is missing. Therefore, the present work analyzes the flooding frequencies on floodplains of three study rivers, Elbe, Main and Rhine. The relation of inundated floodplain extent and current discharge conditions based on detailed results of the established Software Flys is deduced empirically. Based on these subsequently generalized results, finally event related average inundated floodplain extent respectively, incoming nutrient loads are calculated by considering the effects of the hydrologic conditions of each river system. Therefore, available geodata as well as data on water quality and discharge is processed and serves as input data for yearly and monthly empirical retention models. The calculated nutrient retention in floodplains varies with hydrological connectivity of the floodplain to the surface waters as well as with the current hydrologic condition of the river system. For this reason the finally developed concept of event related nutrient retention is suggested as the most realistic in combination with hydro-exponential retention models. The Elbe floodplains are the most natural, and in years with high floods nutrient retention in the floodplains contributes up to 9% respectively 10% of the monthly transported load of TP and NO3-N, which is significant. The transfer of the results to a German-wide application is possible due the generalization of the methods carried out. With the presented results the hydrology dependent role of floodplains for nutrient balances in river systems can be quantified on a landscape scale.
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Shepherd, V. "Beetle diversity of chalk river floodplains." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1420432/.
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Anthropogenic land use changes have increasingly altered and fragmented floodplain landscapes. While the impacts of these alterations are being recognised for many plant and vertebrate taxa, limited information is available for highly diverse invertebrate families. Using a variety of approaches to diversity measurement, this thesis investigates carabid and staphylinid beetle assemblages across a range of chalk floodplain habitats in Norfolk, England. It aims to establish the roles anthropogenic and environmental factors play in shaping their communities in order to inform tailored conservation practices. Site management was identified as the dominant influence on beetle assemblages, underpinning the development of distinct communities amongst floodplain meadow, fen and woodland habitats. Surrounding landscape configuration also influenced beetle assemblages, confirming the wide-ranging, multi-faceted impacts of anthropogenic land use changes. Beetle communities in floodplain woodlands were both specimen- and species-rich across the highly heterogeneous forest microhabitats hosted within. Functional diversity analysis highlighted the vulnerability of certain functional groups to management and fragmentation. It confirmed the importance of conserving remaining remnants of natural floodplain woodlands to support vulnerable beetle communities. Floodplain fens harboured rare species, while their overall beetle diversity was surprisingly low. This was attributed to their limited habitat extent, fragmented distribution, and potentially legacies of past land use. This thesis suggests that traditional management regimes must be maintained in fen habitats, and their connectivity promoted, to safeguard and restore the unique biological communities supported within. Anthropogenic land use changes have increasingly altered and fragmented floodplain landscapes. While the impacts of these alterations are being recognised for many plant and vertebrate taxa, limited information is available for highly diverse invertebrate families. Using a variety of approaches to diversity measurement, this thesis investigates carabid and staphylinid beetle assemblages across a range of chalk floodplain habitats in Norfolk, England. It aims to establish the roles anthropogenic and environmental factors play in shaping their communities in order to inform tailored conservation practices. Site management was identified as the dominant influence on beetle assemblages, underpinning the development of distinct communities amongst floodplain meadow, fen and woodland habitats. Surrounding landscape configuration also influenced beetle assemblages, confirming the wide-ranging, multi-faceted impacts of anthropogenic land use changes. Beetle communities in floodplain woodlands were both specimen- and species-rich across the highly heterogeneous forest microhabitats hosted within. Functional diversity analysis highlighted the vulnerability of certain functional groups to management and fragmentation. It confirmed the importance of conserving remaining remnants of natural floodplain woodlands to support vulnerable beetle communities. Floodplain fens harboured rare species, while their overall beetle diversity was surprisingly low. This was attributed to their limited habitat extent, fragmented distribution, and potentially legacies of past land use. This thesis suggests that traditional management regimes must be maintained in fen habitats, and their connectivity promoted, to safeguard and restore the unique biological communities supported within. This study highlights the importance of adopting habitat-specific conservation objectives to ensure the persistence of specialist species, whilst maintaining a matrix of different floodplain habitats to preserve wider catchment diversity. As anthropogenic impacts on floodplain environments will continue, the potential role of beetles in biodiversity research and conservation, and in particular of staphylinid beetles that dominate the floodplain ground fauna, warrants increasing interest and recognition.
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Brill, Katie Ellen. "Impacts of inundation and season on greenhouse gas fluxes from a low-order floodplain." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/19213.
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The global climate is changing and much of this is attributed to the greenhouse effect, which has been exacerbated by increased anthropogenic releases of greenhouse gases (GHGs). However, important GHGs, carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4), are produced naturally in the soil during the metabolism of many soil microbial and plant communities. The generation rate of GHGs depends on many factors, including soil community composition, nutrient availability, temperature, and soil moisture. Predicted climate variability is expected to alter temperature and rainfall patterns, which can impact the factors regulating natural generation of GHGs. With changing fluxes of GHGs, the natural feedback loops between GHG generation and climate may change. Increased emissions from natural sources would exacerbate climate change, whereas decreased emissions may mitigate its impacts. Floodplains may be particularly susceptible to climate change, as their biogeochemical processing is driven by hydrology. For this study, ten mesocosms were installed on the floodplain of Stroubles Creek in southwest Virginia. A flood event was simulated in half of these mesocosms in both early spring and mid-summer, which represent extremes in soil moisture and primary productivity on the floodplain. Headspace gases were monitored for CO, N2O, and CH4. Efflux of CO2 and N2O was higher in summer than spring, and also increased following wetting events. Methane production was greater in the spring, with no detectable change with wetting. Increases in summer rainfall events could increase the release of important GHGs to the atmosphere, potentially at levels significant to climate change.Master of Science
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Leigh, Catherine. "Floodplain River Function in Australia's Wet/Dry Tropics, With Special Reference to Aquatic Macroinvertebrates and the Gulf of Carpentaria." Thesis, Griffith University, 2009. http://hdl.handle.net/10072/367453.
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This thesis provides significant insight into our understanding of river function in highly
seasonal systems. In north Australia’s vast wet/dry tropics, large rivers and associated
wetlands are regarded among the continent’s most biologically diverse and ecologically
healthy. Until recently however, research on the hydrology, biodiversity and function of
Australian rivers has focussed on the south. My thesis investigates floodplain river
function in Australia’s wet/dry tropics, more specifically in the Gulf of Carpentaria
drainage division, and is the first to present a dynamic conceptual model of river
function for these systems.
Three major themes reside within riverine ecology: flow, pattern and process. These
themes feature within existing conceptual models of large river function, for example,
the River Continuum Concept, the Flood Pulse Concept and the Riverine Productivity
Model. These themes and models were used as a template to explore river function in
the study region: flow, as broad-scale hydrology and more localised hydrological
connectivity; patterns, as spatiotemporal variation in aquatic macroinvertebrate
biodiversity; and processes, as organic carbon flow through aquatic macroinvertebrate
food webs.
The flow regime is major driver of river function, and as such, a multivariate analysis of
daily flow data from large, Gulf of Carpentaria rivers was conducted. Two major classes
of river were found, each with a distinct flow regime type: ‘tropical’ rivers were
characterised by flow regularity and permanent hydrological connection, ‘dryland’
rivers by high levels of flow variability and ephemerality, similar to rivers in Australia’s
central and semi-arid zones. However, both river types experienced seasonal change,
associated with higher flow magnitudes in the wet and lower flow magnitudes in the
dry, with ‘dryland’ rivers typified by greater numbers of zero flow days. These
features—flow regularity and permanence for ‘tropical’ rivers, flow variability and
absence for ‘dryland’ rivers, and wet/dry seasonality for both river types—were
proposed as the broad-scale hydrological drivers of river function in the Gulf region and
are expected to be found as important drivers throughout the wet/dry tropics.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Pernik, Maribeth. "Mixing processes in a river-floodplain system." Thesis, Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/19514.
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Rose, Michael. "Phosphorous dynamics in periodically flooded and drained riparian soils." Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367719.
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The aim of the research was to evaluate the processes that determine P stability in riparian floodplain soils, with emphasis on chemical transformations in flood-drained calcareous soil. Flooding of soil columns showed an increase in P solubility (from 0.01 to 1.2 μg ml-1) largely due to the reductive dissolution of Fe minerals (solution Fe increased from < 0.05 to > 50 μg ml-1) and increased solubility of Ca-P minerals (solution Ca increased from < 100 to > 1000 μg ml-1). The periodic drainage of the flooded soil exported the equivalent of approximately O.l5 kg ha-1 (over six flood-drain cycles). Exported P correlated with soil solution P immediately before drainage (r2 = 0.99; P < 0.001). After drainage, there was a reversal of the reactions described above, with solution Fe, Ca and P returning to preflooding levels. Over the course of the 6 flood-drain cycles inorganic P became more stable, with Ca-P and Fe-P pools increasing (from 9 and 11 % respectively both to 14 % of TP) at the expense of labile pools. Similar patterns of P release and retention were observed during batch incubation studies of aerobic - anaerobic cycles using moist soil samples. Solution P and Fe were strongly correlated in both non-calcareous (r2 = 0.96) and calcareous (r2 = 0.73) soils. The role of Ca-P mineral solubility was disguised by the dissolution of calcium carbonate. Drying of the soil can lead to P release on re-wetting (up to eight-fold). This is most likely due to a release of P from ruptured microbial cells and transformations of Fe mineral surfaces. Monitoring suggested that all of these processes were active in the field, as the water table advanced and receded, though more slowly than in the laboratory. Over a four month flood-drain cycle losses of dissolved P from the floodplain were estimated at 0.034 kg ha-1. It is unlikely that this is significant relative to upstream inputs of P to the river from point sources and other types of agricultural land in the River Thames catchment.
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Taylor, Mark P. "Holocene sedimentation in River Severn catchments." Thesis, Aberystwyth University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337496.
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Kruske, Montana L., and Dr Eileen G. Ernenwein. "Paleochannel or Palisade? Preliminary Geophysical Investigations of a Linear Feature at the Runion Archaeological Site, Washington County, Tennessee." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/74.
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Runion is a protohistoric Native American village located on the floodplain of the Nolichucky River in western Washington County. Previous archaeological excavations and radiocarbon dates suggest that the village was occupied during the mid-16th to mid-17th century. The Nolichucky River, in contrast, has been flowing through the area for millennia. Geophysical surveys are used to image the subsurface non-invasively, without disturbing protected land and/or organisms. Preliminary geophysical data collected at Runion include ground penetrating radar (GPR), electromagnetic induction (EMI), and magnetometry. These data show a linear feature surrounding the protohistoric village. Given its placement around the margins of the village, the feature could be interpreted as a fortification ditch, which is often paired with a palisade wall to defend a village from attack. The feature is also consistent with typical meandering floodplain stratigraphy, where sections of channel are often abandoned to form oxbow lakes. Over time these abandoned channels fill in and are called paleochannels.
Each geophysical method measures the properties and characteristics of the linear feature, a presumed paleochannel. GPR sends electromagnetic radar waves into the ground, which reflect off different subsurface layers and are recorded as radargrams. Magnetometry measures subtle changes in earth magnetism, including the magnetization of rocks, soils, and/or ferrous objects. EMI systems transmit low frequency electromagnetic waves to measure both electrical conductivity (EC) and magnetic susceptibility (MS). Each of these instruments are used to collect data in transects and then processed to produce profiles, maps and, in the case of GPR, three-dimensional datasets of the subsurface.
It is anticipated that GPR will reveal details about the stratigraphy of the linear feature. Magnetic, EC, and MS measurements will further help to interpret the GPR data by distinguishing between different types of sediments. These data may show if the feature is a paleochannel or a ditch excavated into older stratigraphic layers by village inhabitants for fortification. Ultimately, the feature will be tested with soil cores to study the sediments directly.
At this preliminary stage the feature is interpreted to be a paleochannel. The stratigraphic layers revealed by GPR show a broad depression with stratigraphic layers characteristic of a paleochannel. In addition, magnetic readings are anomalously low on the eastern margin (closer to the modern river channel) and high on the western margin. This could indicate paired point bar sands and paleochannel fill, respectively. This interpretation is still tentative, however, because we have not yet integrated the EMI data, extracted soil cores, or dated the feature. Radiocarbon dates might help determine the relative age of the feature if organic carbon is present. In conclusion, preliminary data currently suggests that the structure is geological rather than archaeological. In the coming months we will collect more GPR data with different frequency GPR antennas, integrate the EMI data, and test the findings by extracting soil cores and reconstructing the stratigraphy.
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Sims, Neil C. "The landscape-scale structure and functioning of floodplains." Connect to this title online, 2004. http://cicada.canberra.edu.au/public/adt-AUC20050706.095439/.
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Thesis (Ph. D.)--University of Canberra, 2004.Title from PDF title page (viewed on July 20, 2005). Pages 185-194 lacking in digital version of thesis. Includes bibliographical references (p. 155-184).
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Weatherholt, Laura. "Floodplains on the prairie: an ecological schoolyard design." Kansas State University, 2012. http://hdl.handle.net/2097/13767.
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Master of Landscape ArchitectureDepartment of Landscape Architecture, Regional and Community Planning
Mary Catherine (Katie) Kingery-Page
Man has been learning in the outdoors since the beginning of humankind. Modern times have reduced the amount of time people spend learning and exploring outside. This causes humans to be disconnected from the natural environment. By making schoolyards more environmentally focused, conducive to outdoor education and play, formal education can return to the original classroom–nature– and inspire people to reconnect with their environment. Much literature supports the ideas of aligning the efforts of play and education, environmental interpretation and education, and outdoor education with formal education; by incorporating all of these elements in a schoolyard, the potential for enriched learning is greatly increased. This project explores nature interpretation strategies used by public botanic gardens and translates these strategies to an ecological schoolyard. At Northview Elementary School in Manhattan, Kansas, the students face a simple, sterile play-yard with flooding limiting site use after storm events. The design for Northview Elementary will integrate stormwater features with school needs into a new ecological master plan for campus. Interpreting this landscape using the strategies adapted from botanical gardens for educational approaches, methods, and interpretive displays, provides the school and community a resource to enhance their lives, education, and the environment.
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Truchan, Jessie J. "Genesis of Carbonate Lakes on Perennial Siliciclastic Floodplains." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1242778273.
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Werth, David E. Jr. "Predicting Resistance and Stability of Vegetation in Floodplains." DigitalCommons@USU, 1997. https://digitalcommons.usu.edu/etd/4459.
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To calculate flow or depth in a waterway, it is necessary to accurately determine the flow resistance. Past research has made considerable progress in predicting the roughness of nonvegetated uniform channels based on both theoretical and experimental investigations. However, to determine the flow resistance associated with vegetated compound flow channels and floodplains, the effects of the vegetation must be considered.
Recent advancements have led to greater understanding of the effects of partially submerged uniform vegetation in a waterway. However, to accurately determine flow resistance, it is imperative that the effects of both submerged and partially submerged vegetation be taken into account. It is also critical to account for the effects of multiple species and densities of vegetation throughout the waterway.
Extensive testing of both partially submerged and fully submerged vegetation was completed in the laboratory. Multiple species were tested together to represent various ecosystems commonly found in floodplains throughout the country. Results of the testing show that both geometric and biomechanical properties of the plants must be accounted for when determining vegetation resistance. Methods and procedures were developed to quantify these properties. Equations were also developed that provide a basis by which to quantify vegetation resistance.
The results of this study were compared to several sets of actual field data. The resistance values predicted by the equations were very close to those measured in the field. Use of the developed equations and procedures now provides those involved in the field of flood control a far more accurate tool by which to predict vegetation resistance than was previously available.
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Anderson, Michelle Louise. "The edge effect lateral habitat ecology of an alluvial river flood plain /." Diss., [Missoula, Mont.] : The University of Montana, 2009. http://etd.lib.umt.edu/theses/available/etd-10012008-134442/.
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Westwater, David. "Modelling hydrodynamic and shallow water processes over vegetated floodplains." Thesis, Cardiff University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391534.
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Brooker, Michael R. "Physical and Chemical Characterization of Self-Developing Agricultural Floodplains." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1513778530623727.
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Yu, Dapeng. "Diffusion-based modelling of flood inundation over complex floodplains." Thesis, University of Leeds, 2005. http://etheses.whiterose.ac.uk/3360/.
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High-resolution data obtained from airborne remote sensing are increasing opportunities for representation of small-scale structural elements (e. g. walls, buildings) in complex floodplain systems using two-dimensional (2D) models of flood inundation. At the same time, 2D inundation models have been developed and shown to provide good predictions of flood inundation extent, with respect to both full solution of the depth-averaged Navier-Stokes equations and simplified diffusion wave models. However, these models have yet to be applied extensively to urban areas. This study applies a 2D raster-based diffusion wave model, either loosely-coupled or tightly-coupled to a ID river flow model, to determine patterns of fluvial flood inundation in urban areas using high-resolution topographic data. The aim of this study is to explore the interaction between spatial resolution and small-scale flow routing process, through model validation and verification. The model assumes that the prime source of the flood is fluvial: pluvial floods and floods associated with urban drainage systems are not addressed. The topographic data are based upon airborne laser altimetry (LiDAR) obtained for the City of York, U.K. Validation data were available in the form of inundation patterns obtained using aerial photography at a point on the failing limb of the flood event. Inflow data is provided either by a loosely-coupled or a tightly-coupled ID river flow model. The model was used to simulate a major flood event which occurred in the year 2000 in the City of York on the River Ouse at 4 different sites. Applications of the basic model showed that even relatively small changes in model resolution have considerable effects on the predicted inundation extent and timing of flood inundation. Timing sensitivity would be expected given the relatively poor representation of inertial processes in a diffusion wave model. Compared with previous work, sensitivity to inundation extent is more surprising and is associated with three connected effects: (i) the smoothing effect of mesh coarsening upon input topographical data; (ii) poorer representation of both cell blockage and surface routing processes as the mesh is coarsened, where the flow routing is especially complex; and (iii) the effects of (i) and (ii) upon water levels and velocities which in turn determine which parts of the floodplain the flow can actually travel to. The combined effects of wetting and roughness parameters can compensate in part for a coarser mesh resolution. However, the coarser the resolution, the poorer the ability to control the inundation process as these parameters not only affect the speed but also the direction of wetting. Thus, high resolution data will need to be coupled to more sophisticated representation of the inundation process in order to obtain effective predictions of flood inundation extent. A sub grid scale wetting and drying correction approach was developed and tested for use with 2D diffusion wave models of urban flood inundation. The method recognises explicitly that representations of sub grid scale topography using roughness parameters ill provide an inadequate representation of the effects of structural elements on the floodplain (e. g. buildings, walls) as such elements not only act as momentum sinks, but also have mass blockage effects. The latter may dominate, especially in structurally complex urban areas. The approach developed uses high resolution topographic data to develop explicit parameterization of sub grid scale topographic variability to represent both the volume of a grid cell that can be occupied by the flow and the effect of that variability upon the timing and direction of the lateral fluxes. This approach is found to give significantly better prediction of fluvial flood inundation in urban areas as compared with traditional calibration of sub grid-scale effects using Manning's n. In particular, it simultaneously reduces the need to use exceptionally high values of n to represent the effects of using coarser meshes, whilst simultaneously increasing the sensitivity of model predictions to variation in n. Finally, the model was coupled (tightly) to a one-dimensional solution of the Navier-Stokes equations. This showed that significantly better representation of urban inundation could be achieved in a tightly-coupled formulation as a result of better representation of boundary condition effects.
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Leigh, Catherine. "Floodplain river function in Australia's wet/dry tropics, with specific reference to aquatic macroinvertebrates and the Gulf of Carpentaria." Thesis, Griffith University, 2009. https://eprints.qut.edu.au/119606/1/Leigh_2009_02Thesis.pdf.
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This thesis provides significant insight into our understanding of river function in highly seasonal systems. In north Australia’s vast wet/dry tropics, large rivers and associated wetlands are regarded among the continent’s most biologically diverse and ecologically healthy. Until recently however, research on the hydrology, biodiversity and function of Australian rivers has focussed on the south. My thesis investigates floodplain river function in Australia’s wet/dry tropics, more specifically in the Gulf of Carpentaria drainage division, and is the first to present a dynamic conceptual model of river function for these systems. Three major themes reside within riverine ecology: flow, pattern and process. These themes feature within existing conceptual models of large river function, for example, the River Continuum Concept, the Flood Pulse Concept and the Riverine Productivity Model. These themes and models were used as a template to explore river function in the study region: flow, as broad-scale hydrology and more localised hydrological connectivity; patterns, as spatiotemporal variation in aquatic macroinvertebrate biodiversity; and processes, as organic carbon flow through aquatic macroinvertebrate food webs. The flow regime is major driver of river function, and as such, a multivariate analysis of daily flow data from large, Gulf of Carpentaria rivers was conducted. Two major classes of river were found, each with a distinct flow regime type: ‘tropical’ rivers were characterised by flow regularity and permanent hydrological connection, ‘dryland’ rivers by high levels of flow variability and ephemerality, similar to rivers in Australia’s central and semi-arid zones. However, both river types experienced seasonal change, associated with higher flow magnitudes in the wet and lower flow magnitudes in the dry, with ‘dryland’ rivers typified by greater numbers of zero flow days. These features—flow regularity and permanence for ‘tropical’ rivers, flow variability and absence for ‘dryland’ rivers, and wet/dry seasonality for both river types—were proposed as the broad-scale hydrological drivers of river function in the Gulf region and are expected to be found as important drivers throughout the wet/dry tropics.
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Bogoni, Manuel. "Long-term evolution of meandering rivers flowing above heterogeneous floodplains." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3424896.
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Floodplains, and rivers therein, constitute complex systems whose simulation involves modelling of hydrodynamic, morphodynamic, chemical, and biological processes which act, affecting each other, over a wide range of time scales (from days to centuries). Floodplain morphology and stratigraphy are shaped by the interplay of water flow, erosion, and deposition consequent to repeated flood events, as the river dissecting the floodplain evolves through feedbacks between bars, channels, vegetation and sediment characteristics shaping the floodplain itself.
The first topic of this thesis concerns the mutual interactions that leads to self-formed floodplains, produced by the sedimentary processes associated with the migration of river bends and the formation of abandoned oxbow lakes consequent to the cutoff of mature meanders.
The second topic addresses the presence of internal boundary conditions able to affect the main flow field and thus the curvature-driven flow that drives bend migration.
Point bar deposits and oxbow lakes are the products of lateral bend migration and meander cutoffs. The sediment deposits characterizing these geomorphic units link together the long term evolution of an alluvial river and the surrounding floodplain, altering the soil composition and, hence, bank strength controlling the rate of channel meandering.
On the other hand, a localized forcing internal to the main flow field (e.g., a variation in bed slope or in flow discharge) propagates either upstream or downstream, affecting the river dynamics.
Multivariate statistical and spectral tools may disclose the complexity of the resulting planform geometries, either simulated or natural, ensuring an objective comparison.Le piane alluvionali e i relativi fiumi costituiscono complessi sistemi dinamici la cui simulazione numerica richiede la modellazione di processi idrodinamici, morfodinamici, chimici e biologici agenti mutuamente su varie scale temporali (dai giorni ai secoli). La morfologia e la stratigrafia della piana alluvionale sono determinate dalla mutua interazione tra flussi idrici, erosione e deposito di sedimenti dovuti a ripetuti eventi di piena. Barre alluvionali, canali abbandonati, caratteristiche dei sedimenti e della vegetazione giocano un ruolo chiave nella storia migratoria del fiume che scorre sulla superficie alluvionale. Il primo argomento di questa tesi riguarda l'interazione mutua tra fiume e piana alluvionale, prodotta dai processi sedimentologici che modificano la struttura della superficie alluvionale influendo sulla migrazione del fiume e, allo stesso tempo, sono determinati dai processi legati dalla migrazione stessa. Tali processi consistono in progressivi depositi nella parte interna delle curve (point bars) fino ai cutoffs che portano alla formazione di anse abbandonate, contribuendo ad alterare la resistenza all'erosione del suolo da parte del fiume stesso. Il secondo argomento riguarda la presenza di condizioni al contorno interne che sono in grado di influire sulle caratteristiche del campo di moto, il quale è legato alla distribuzione della curvatura planimetrica dei meandri. La presenza di una singolarità (e.g., variazione di portata dovuta alla confluenza con un affluente) genera perturbazioni al campo di moto che si propagano verso monte e verso valle, influendo sulla dinamica a breve e a lungo termine del fiume. Metodi statistici spettrali e multivariati permettono di analizzare e confrontare oggettivamente le geometrie dei meandri fluviali, sia naturali che generati numericamente.
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Bonyongo, Mpaphi Casper. "Vegetation ecology of the seasonal floodplains in the Okavango Delta, Botswana." Diss., Connect to this title online, 1999. http://upetd.up.ac.za/thesis/available/etd-03012007-103712/.
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Vega, Luisa F. [Verfasser]. "Ecology of seasonal shallow lakes in neotropical floodplains / Luisa F. Vega." Konstanz : Bibliothek der Universität Konstanz, 2014. http://d-nb.info/1081016256/34.
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Teo, Fang Yenn. "Study of the hydrodynamic processes of rivers and floodplains with obstructions." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/54161/.
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A study has been undertaken to supplement design methods and develop innovative approaches for the effective management of rivers and floodplains to reduce flood risk. The focus has been on enhancing the understanding and representation of the hydrodynamic processes of a variety of flow conditions and the associated hydraulic interaction with selected obstruction types, such as mangroves and vehicles for the representative river basins of the Merbok and Klang, on the West Coast of Peninsular Malaysia, and the Valency, near Boscastle, in the UK. For the study of the hydrodynamic processes of natural floodplains, a numerical model has been refined to investigate the effects of mangroves on tsunamis, with the inclusion of modelling idealised test cases. A similar model has then been applied to a mangrove fringed floodplain for the Merbok river basin. In recognising the importance of mangroves as natural defences against flooding disasters, a novel innovative and environmentally friendly approach, namely the Artificial Mangrove Shelter (AMS), has been first initiated and modelled, for the sustainable restoration and rehabilitation of mangroves along floodplains. In studying the hydrodynamic processes of urban floodplains, a series of experimental investigations has been undertaken on stationary scaled model vehicles in laboratory flumes, to study the effects of vehicles on flood flow propagation and, the influence of the flood flows on the stability of the vehicles. In order to develop a useful innovative approach to evaluate the degree of hydraulic stability for vehicles, a novel three colour zone envelope curve has been first introduced and developed, herein known as the Traffic Light of Hydraulic Stability (TLHS), to identify the likelihood of vehicle movement. The study was then extended to investigate the consequential hydraulic impact of flooded vehicles on blocked bridges, through a physical modelling study in a laboratory flume, with the purpose being to replicate a typical section of prototype floodplain conditions for the Boscastle and Klang. In this study, eventually natural and urban environments along the rivers and floodplains have consideration the hydrodynamic processes and interaction between hydraulic obstructions and flood flows, with novel and practical approaches being developed for effective management of rivers and floodplains.
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Rezaei, Bahram. "Overbank flow in compound channels with prismatic and non-prismatic floodplains." Thesis, University of Birmingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.564484.
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Two sets of experiments have been undertaken in compound channels with prismatic and nonprismatic floodplains with different floodplain widths and convergence angles in order to investigate flow behaviour in two-stage channels. Measurements were made of water surface profile, depth-averaged velocity, boundary shear stress distributions and velocity distributions and the results are presented in graphical and tabulated form. Empirical equations have been derived from each type of compound channel, allowing predictions to be made concerning the resistance parameters, n and f, the discharge, Q, the proportion of total flow in sub-areas, %Qj, the evolution of flow in the main channel and on the floodplain along the converging part of the flume, the boundary shear forces, SFj, and the apparent shear forces at a vertical and horizontal interface between the main channel and the floodplain, for a given stage, H. The percentage of flow in the main channel and on the floodplain, as well as the percentage of the boundary shear forces carried by each element in different sections of the compound channel with non-prismatic floodplains, were then compared with the prismatic floodplain cases with the same geometry. The results of these two sets of experiments indicate that they follow the same pattern, although there are some differences due to the effects of backwater and convergence in the flume. The apparent shear forces on a vertical interface, ASFv, are however remarkably different. Based on momentum balance, an analytical approach was developed to estimate the water surface profile in non-prismatic compound channels with different convergence angles, 9. The calculated water surface profiles compared well with the measured ones. It is shown that the Shiono and Knight Method (SKM) predicted lateral distributions of the depth-averaged velocity and boundary shear stress well, especially for prismatic compound channels with wide floodplains. Furthermore, there is a good agreement between the measured and predicted distributions in non-prismatic compound channels, provided the energy slope, Se,is used instead of the bed slope, So. The experimental results were then also used to calibrate the two parameter, ",t, and ",g, in the Exchange Discharge Model (EDM). This revealed that the calibration of the turbulent exchange parameter, wt strongly depends on the Manning's roughness coefficient. In term of compound channels with non-prismatic floodplains it is also shown that the EDM always overestimates the flow discharge for a specific stage.
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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.
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Mountainous regions are ubiquitously dissected by river networks. These networks are the main drivers by which climate and tectonic signals are transmitted to the rest of the landscape, and control the response timescale of the landscape to these external forcings. Furthermore, river systems set the downslope boundary conditions for hillslope sediment transport, which controls landscape denudation. Therefore, understanding the controls on the organisation and structure of river networks in upland landscapes is an important goal in Earth surface processes research. The recent introduction of high-resolution topographic data, such as airborne lidar data, has revolutionised our ability to extract information from the topography, providing new opportunities for linking geomorphic process with landscape form. This thesis is focused on developing techniques for analysing high-resolution topographic data to quantify and understand controls on the structure of fiuvial systems in upland landscapes. Firstly, I develop and test new algorithms for objective feature extraction from lidar-derived digital elevation models (DEMs). I present a new method for identifying the upstream extent of channel processes by identifying scaling breaks in river long profiles. I then compare this new method to three existing methods of channel extraction, using field-mapped channel heads from four field sites in the US. I find that the new method presented here, along with another method of identifying channels based on valley geometry, most accurately reproduces the measured channel heads in all four field sites. I then present a new method for identifying floodplains and fiuvial terraces from DEMs based on two thresholds: local gradient, and elevation compared to the nearest channel. These thresholds are calculated statistically from the DEM using quantile-quantile plots and do not need to be set manually for each landscape in question. I test this new method against field-mapped floodplain initiation points, published flood hazard maps, and digitised terrace surfaces from eight field sites in both the US and the UK. This method provides a new tool for rapidly and objectively identifying floodplain and terrace features on a landscape scale, with applications including flood risk mapping, landscape evolution modelling, and quantification of sediment storage and routing. Finally, I apply these new algorithms to examine the density of channel networks across a range of mountainous landscapes, and explore implications for fluvial incision models. I compare the relationship between drainage density (Dd) and erosion rate (E) using both analytical solutions and numerical modelling, and find that varying the channel slope exponent (n) in detachment-limited fluvial incision models controls the relationship between Dd and E. Following on from this, I quantify Dd for five field sites throughout the US. For two of these field sites I compare Dd to cosmogenic radionuclide (CRN)-derived erosion rates, and for each site I use mean hilltop curvature as a proxy for erosion rate where CRN-derived erosion rates are not available. I find that there is a significant positive relationship between Dd, E, and hilltop curvature across four out of the five field sites. In contrast to assumptions made in many studies of fluvial incision, this positive relationship suggests that the channel slope exponent n is greater than unity for each of these landscapes, with fundamental implications for both landscape evolution and sediment transport.
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Bechtold, James Scott. "Fluvial sediment influences on floodplain soil biogeochemistry /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/5358.
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Denys, Frank. "Transverse transport of suspended sediment across the main channel - floodplain shear boundary /." Link to the online version, 2007. http://hdl.handle.net/10019/415.
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Michaelides, Katerina. "The effects of hillslope-channel coupling on catchment hydrological response in Mediterranean areas." Thesis, King's College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326964.
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Barsoum, Nadia. "A comparison of vegetative and non-vegetative regeneration strategies in Populus nigra and Salix alba." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364532.
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Spurgeon, V. Leanne. "Sedimentology of historic and prehistoric deposits in the drainage basin of Deep River and Muddy Creek on the Piedmont of North Carolina." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1268.
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Thesis (M.S.)--West Virginia University, 2000.Title from document title page. Document formatted into pages; contains viii, 152 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 62-64).
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Shah, Mohammad Aminur Rahman. "Decision Support Framework for Sustainability Assessment of Flood Mitigation Projects." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/371222.
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Sustainable development of floodplains is closely linked to sustainable flood mitigation measures. Various sustainability assessment (SA) methods to evaluate the influence of policies, plans or projects aimed towards sustainable development have been emerging in recent years. However, most of them are at the national or regional level. Very few research studies have been carried out for sustainability assessment of flood mitigation projects. This study proposes a new innovative decision support framework for sustainability assessment (SA) of flood mitigation projects throughout the project life cycle, focusing on two main aspects: sustainable flood mitigation by the project, and enabling of sustainable development of the floodplain. This study has employed a review of the life cycle of flood mitigation projects, a review of sustainability assessment methodologies, consultations with experts and case studies involving two flood mitigation projects in Queensland, Australia. Conforming to the project life cycle, the decision support framework for sustainability assessment of flood mitigation projects is developed incorporating five stages: 1) contextualizing the project with regard to floodplain sustainability, 2) SA during planning and implementation for integrating sustainability issues in the project, 3) SA during a flood event to assess the sustainability performance of the project 4) SA at periodic intervals, and 5) SA at the stage of modification or changing to a new project. The framework has adopted a multi-criteria analysis (MCA) approach using sustainability criteria and indicators to determine the sustainability index for the project.
The process of selecting indicators, defining the weightages and scores for indicators, and determining a sustainability index for various stages of the project has been described in this thesis. The application of the SA framework to the first two stages of the two case study flood levee projects demonstrates how the best suitable alternative levee option can be chosen in the planning stage by determining a sustainability index (SI) of the possible alternatives using a set of sustainability indicators. The study also shows achievement towards sustainability of the finally implemented project can be compared with the originally planned project using the SA framework. The application of the SA framework suggests the potential for better decision making for individual flood mitigation projects, taking into account the sustainable outcomes of the project as well as linking these to sustainable regional development. The outcome of this study will enhance decision making for sustainability of flood mitigation projects. Adapting the framework to projects in other development sectors is also envisaged.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Louca, Vasilis. "The ecology of fishes and mosquitoes of the lower Gambia River floodplains." Thesis, Durham University, 2009. http://etheses.dur.ac.uk/2082/.
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This study investigated aspects of the ecology of fishes and mosquitoes using floodplains in the lower reaches of the Gambia River, a semi-arid river system. The Gambia River, situated at the edge of the Sahel, represents one of the few remaining major river systems not to have been impacted by any impoundments. It was hypothesised that seasonal variations in physical variables particularly related to the pattern of flooding and drying influence fish species distribution; the presence of some of these species probably also influencing mosquito larvae distribution. Fish and mosquito larvae were sampled along two lateral transects on the floodplain in The Gambia, from May to November 2005 - 2007. Water conductivity, pH and water depth all influenced fish species richness and bolongs (creeks) held greater species richness compared with other floodplain habitats, probably because they acted as conduits for fish moving on and off the floodplain. Species richness and catch biomass increased rapidly following the first rains and then declined. The Guinean tilapia, Tilapia guineensis, was the dominant species on the floodplains and its catches were positively associated with higher levels of conductivity and dissolved oxygen, shallower water and less vegetation cover. The Guinean tilapia is primarily an iliophage and the catches varied seasonally. Controlled experiments using T. guineensis in tanks with shallow water barriers showed that fish density plays a significant role in triggering fish emigration, whereas a lack of food available caused an increase in exploratory behaviour but with no impact on successful emigration. The influence of fish on the distribution of mosquito larvae on the floodplains was investigated. Semi-field trials were used to test two possible mechanisms for this influence: direct predation and oviposition avoidance due to the presence of fish chemical cues. The presence of T. guineensis decreased the chance of finding culicine larvae in the field possibly due to culicine mosquito avoiding ovipositing in habitats with fish present as fewer culicines oviposited in experimental tanks with fish, suggesting that ovipositing culicine females avoid water with fish. In contrast, oviposition by anophelines was unaffected by fish. Both fish species tested, T. guineensis and a common insectivore, Epiplatys spilargyreius were effective predators removing all late-stage culicine and anopheline larvae. In order to determine the relationships between mosquito distribution and the physical environment in an urban setting, mosquitoes were collected and environmental physical parameters were measured in and around Farafenni town, located at the edge of the foodplains in The Gambia. Levels of reactive phosphorus, distance from the nearest house, turbidity, amount of vegetation cover and the presence of algae all influenced the occurence of mosquito larvae collected in and around Farafeimi town. Anopheles arabiensis was found closer to houses than Anopheles gambiae sensu stricto and the presence of algae was a strong indicator of the presence of anopheline larvae in general. Sites dominated by anophelines had higher turbidity levels compared to sites in which culicines dominated. Production of pupae was associated with high levels of reactive phosphorus concentrations. The results are discussed in the context of world climate change, anthropogenic impacts on large rivers and increased urbanisation.
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Azinheira, David Lee. "Complementary Effects of In-Stream Structures and Inset Floodplains on Solute Retention." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/51046.
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The pollution of streams and rivers is a growing concern, and environmental guidance increasingly suggests stream restoration to improve water quality. �Solute retention in off channel storage zones such as hyporheic zones and floodplains is typically necessary for significant reaction to occur. �Yet the effects of two common restoration techniques, in stream structures and inset floodplains, on solute retention have not been rigorously compared. �We used MIKE SHE to model hydraulics and solute transport in the channel, inset floodplain, and hyporheic zone of a 2nd order stream. �We varied hydraulic conditions (winter baseflow, summer baseflow, and storm flow), geology (hydraulic conductivity), and stream restoration design parameters (inset floodplain length, and presence of in stream structures). �In stream structures induced hyporheic exchange during summer baseflow with a low groundwater table (~20% of the year), while floodplains only retained solutes during storm flow conditions (~1% of the year). �Flow through the hyporheic zone increased linearly with hydraulic conductivity, while residence times decreased linearly. �Flow through inset floodplains and residence times in both the channel and floodplains increased non linearly with the fraction of bank with floodplains installed. �The fraction of stream flow that entered inset floodplains was one to three orders of magnitude higher than that through the hyporheic zone, while the residence time and mass storage in the hyporheic zone was one to five orders of magnitude larger than that in floodplain segments. �Our model results suggest that in stream structures and inset floodplains are complementary practices.Master of Science
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Molinari, Bianca S. "Aquatic Productivity and Connectivity in a Tropical River Floodplain." Thesis, Griffith University, 2021. http://hdl.handle.net/10072/405196.
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Floodplains are highly productive and biodiverse ecosystems, and they provide many environmental services. Despite their importance, floodplains are under increasing pressure from human development and climate change. Worldwide, floodplains have witnessed those pressures translating into impacts that ultimately cause altered connectivity and impaired primary and secondary production. River floodplains in northern Australia are relatively intact compared to their counterparts in Australia, and play an important role in sustaining aquatic food webs. However, significant interest in agricultural expansion is being considered in northern Australia and the proposed intensive land and water resource development creates ecological concerns. The ecological functioning of those ecosystems relies on landscape connectivity and primary productivity. However, despite the importance of floodplain wetlands and the threats they face, a lack of information on those processes is apparent.
The objective of this thesis is to develop a framework that accounts for primary production and connectivity in order to (a) inform river managers when identifying where to focus management and conservation efforts and (b) inform decision-makers in order to prioritise investment plans. Using the Mitchell River floodplain as a study area, I integrated field work, statistical models, remote sensing and graph theory to estimate rates of algal production and their statistical relationship to environmental features (Chapter 2); upscale those relationships across the landscape to identify hotspots of algal productivity (Chapter 3); and analyse connectivity across the Mitchell River floodplain and how water resources development can impact algal productivity and landscape connectivity (Chapter 4). The reason for focusing on algal production, especially epiphytic algae growing on aquatic macrophytes, is that this has been shown to be the major basal food resource for fish and other aquatic consumers in these river-floodplain systems, even though they represent a small fraction of the total primary productivity biomass.
To address the first goal, I identified the environmental features that could be used to predict algal productivity and built a statistical model to measure the relationships between those environmental features and algal primary productivity. The observed data were obtained during field work, where I performed experiments to quantify the rates of algal production and measured physical, chemical and biological environmental features across a range of different wetland types and habitats in the Mitchell River floodplain. This analysis showed that turbidity and habitat type (as presence and type of aquatic vascular plants) are important predictors of algal productivity. This methodology demonstrated that the use of those predictors can provide an important tool for predicting algal productivity across the floodplain.
To tackle the second goal, I adapted the statistical relationships found in the first chapter to predict algal productivity across larger spatial scales. I then predicted the rates of algal production across the Mitchell River floodplain and identified ‘hotspots’ (= areas of high algal productivity) by using spectral indices and bands from Landsat 8 remotely sensed images. The results of the study suggest that habitats with high algal productivity are located across the floodplain, in ephemeral river channels and wetlands, highlighting the importance of wetland habitats for ecosystem functioning. Further, this study identified an effective and transferrable methodology for mapping algal productivity at large spatial scales.
In the final stage of the research, I developed a framework to understand the implications of hydrological connectivity on the availability of algal food resources in floodplain river ecosystems. Wetland habitats may support areas of high algal production in the riverine-floodplain ecosystem; however, they need to be accessible to mobile higher consumers in order to contribute to secondary production. I first combined the spatial variation of algal productivity (Chapter 3) with modelled scenarios of floodplain inundation using a graph theoretic approach to measure landscape connectivity. I then used this to predict how water resource development scenarios would impact connectivity and algal productivity. From these analyses, I estimated how much algal production would be lost as a result of changes to hydrology and landscape fragmentation. These results showed that water resources development can limit the inundation extent and impair connectivity, hence reducing the input of algal productivity to river–floodplain food webs.
The results of the current research contribute to the fields of remote sensing, ecology and ecosystem management. Collectively the research provides an innovative body of research by combining field data and experiments with satellite-derived data and landscape modelling. The approach to quantifying and localising the sources of algal productivity across the landscape can be integrated into landscape graph theoretic methods to evaluate the impact of water resource development. This methodology, by identifying areas of high ecological value that may be sensitive to development, provides information for decisionmakers and river managers that will help to prioritise important regions based on those ecological assets that are often not considered. This study represents an important step forward because it combines spatial dynamics of primary productivity and connectivity into a comprehensive framework that can offer more ecologically meaningful protection to floodplains wetlands. The Mitchell River floodplain ecosystem provides a valuable case study in a relatively data rich environment, however, this approach could also be adapted for use in other riverine and floodplains ecosystems worldwide to improve future conservation planning and management globally.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Savanhu, G. M. (George Mutangamberi). "Controls on channel form and floodplain character along the Bulstrode River, southern Quebec, Canada." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69683.
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The hydraulic dimensions and planform character of a river channel are very much affected by the channel gradient and the calibre of the bed materials. One of the two major objectives of this study is to analyze these effects on selected reaches along the Bulstrode River, near Victoriaville.The second objective is to relate the variations in gradient, sediment calibre and channel geometry to the changes in floodplain character along the river valley.
The river is about 85 km long and flows across the Appalachian highlands and foothills in southern Quebec. This study focuses on six alluvial reaches along the river, ranging from 0.7 to 1.5 km in length. The channel gradient ranges from 0.0036 to 0.0001. The decline in gradient is associated with rapid downstream fining from small cobble and gravel-bed in the 'upvalley reaches' to a sand-bedded channel in the 'downvalley' reaches.
The discharge remains fairly constant over the river length, averaging about 140 m$ sp3$/sec. Channel depth, particularly the thalweg depth, increases appreciably in the downstream direction. The channel width decreases appreciably in the downstream direction. The channel capacity varies significantly without a clear pattern in the steeper cobble-gravel bed reaches and generally declines in the more hydraulically efficient, gentler and more hydraulically efficient fine gravel-sand bed downstream reaches.
This study finds that floodplain characteristics vary with specific stream power and within-channel processes, but not in the same manner as suggested in the Nanson and Croke (1992) model. (Abstract shortened by UMI.)
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Horn, R. P. "Flow resistance of woody vegetation and velocity estimation for flow over wooded floodplains." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604233.
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This thesis examines the velocity, patterns and resistance of flow through rigid vegetation by analysing experimental studies, and presents a method for measuring the mean velocity of flow within a vegetated floodplain where access during flood conditions may be difficult. Flume studies investigated the influence of vegetation parameters and flow properties on the velocity profile, flow resistance and drag coefficient of emergent and submerged artificial rigid vegetation in the form of cylinders. The mean drag coefficients of the vegetation stands were found to vary with array density, pattern and spacing in the flow and transverse directions, which relate to the shielding effects within the array and flow cross-section contraction due to the dowels. An expression is developed which represents the variation in the mean drag coefficient due to shielding and cross-section contraction. A method using conductivity and dye tracing techniques was developed for measuring mean velocity on vegetated floodplains. Video analysis of the dye plume advection and dispersion enabled estimation of an approximate surface velocity and showed that the general surface flow tended to migrate towards the edge of the floodplain furthest from the main stream. Analysis of the conductivity traces of the passage of a plume of saline solution past an array of conductivity sensors on the floodplain indicated that the sub-surface flow tended to migrate down the floodplain towards the main channel. The velocity increased from the bed to the surface, and a circulatory motion within the floodplain flow from the main channel towards the floodplain at the surface and returning to the main channel closer to the bed was suggested.
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Nicholas, Andrew Paul. "Modelling overbank deposition on floodplains : a case study of the River Culm, Devon." Thesis, University of Exeter, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239297.
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Clitherow, Leonie Rose. "Terrestrial-aquatic food web linkages across floodplains of different ages, Glacier Bay, Alaska." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6676/.
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The linkages between the stream and its riparian zone have been well studied in many diverse systems on short (generally annual) timescales. No research has yet considered this in the context of longer (multi-decadal to centennial) timescales at which landscape and successional processes operate. Glacier Bay National Park and Preserve, in southeast Alaska, has a well-documented history of glacial retreat, which allows for the study of ecosystem development using a space-for-time chronosequence approach. This research was unique in analysing terrestrial invertebrates on floodplains of different ages in Glacier Bay, and was the first to utilise two complementary methods of dietary analysis to study the movement of resources between terrestrial and aquatic habitats at sites of different ages. A combination of gut contents dietary analysis and stable isotope analysis was used to determine the food sources of aquatic and terrestrial consumers. Physical habitat complexity, rather than substrate age alone, was an important factor in structuring reciprocal subsidies. This has clear implications for river managers seeking to restore streams to their natural state, particularly where juvenile salmonids are present, as well as underlining the importance of considering a stream in the wider context of its riparian zone.
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Southwell, Mark, and n/a. "Floodplains as dynamic mosaics : sediment and nutrient patches in a large lowland riverine landscape." University of Canberra. n/a, 2008. http://erl.canberra.edu.au./public/adt-AUC20081217.144116.
Full textAbstract:
Rivers around the world are under increasing pressure from a variety of human activities.
Effective management of riverine landscapes requires an ecosystem approach and one that
recognises the complex interactions between their physical, chemical and biological
components. Perceptions of pattern and process are central to our understanding of riverine
landscapes. Pattern and process operate over multiple scales to produce heterogeneous
mosaics of landscape patches that change over time. Hierarchical patch dynamics provides a
useful approach to unravel pattern and process at multiple scales in riverine landscapes. This
thesis adopts a hierarchical patch dynamics approach to investigate floodplain sediment and
nutrient dynamics within the Barwon-Darling River in South Eastern Australia.
The flow regime of the Barwon-Darling River is highly variable. As a result, it has a complex
channel cross section featuring inset-floodplain surfaces that occur at multiple elevations
within the channel trough. These surfaces formed the focus of this study. The texture of inset- floodplain
surface sediments displays a patchy spatial distribution and one that did not reflect
lateral or longitudinal gradients within this floodplain landscape. Rather a sediment textural
patch mosaic was identified. Nutrient concentrations associated with the surface sediments of
the inset-floodplains were also shown to vary significantly resulting in a nutrient patch
mosaic. This spatial nutrient mosaic was enhanced by factors including the surface elevation
of the floodplain surface.
Sediment and nutrient exchange between the river channel and inset-floodplain surfaces was
measured during several flows in 2001, 2002 and 2005. Pin and sediment trap data showed
that significant quantities of sediment were exchanged between the river channel and
floodplain surfaces during inundation with both cut and fill processes occurring. Patterns in
sediment exchange appear to be related to local sediment supply and seasonal sediment
exhaustion, rather than the top down geomorphic constraints considered. These material
exchanges resulted in a change to the spatial configuration of the sediment textural patch
mosaic. Distinct new sediment textural patches were created following inundation, while
other patches were lost post inundation and other patches changed sediment textural character
to move into pre-existing patches. Thus a truly dynamic sediment textural mosaic exists
within this floodplain landscape.
Nutrient concentrations associated with floodplain sediments also changed over time. While
nutrient concentrations increased after the December 2001 flow event, they generally
decreased after the March 2002 event, highlighting their dynamic nature over time. The
spatial distribution of nutrient concentrations also varied over time, with a 40 percent change
to the nutrient mosaic as a result of the March 2002 flow event. In addition to the influence of
the changing physical template (sediment texture mosaic), nutrient concentrations were
shown to be influenced by rainfall processes on non flooded surfaces, and also a number of
top-down constraints and bottom-up influences operating over multiple spatial scales.
Overall, the inset-floodplains studied in this thesis acted primarily as sediment and nutrient
sinks, and were a source for dissolved nutrients. Nutrient exchange was associated with the
exchange of sediments in this riverine landscape, over both inter-flow and decadal timescales.
It was demonstrated that water resource development within the catchment reduced the
number, magnitude and duration of flow events down the Barwon-Darling River and as a
result reductions in the exchange of sediment, associated and dissolved nutrients between
inset-floodplains and the main river channel were calculated. The greatest reductions were
with the release of dissolved nutrients (42-25 percent) and the exchange of sediment and
associated nutrients from high level surfaces (43 percent).
Effective conservation and management of riverine ecosystems must occur at the correct
scale. This study identified potential nutrient hotspots at several scales in the Barwon-Darling
floodplain landscape that could be targeted by management. The low predictability of the
location of nutrient hotspots at the inset-floodplain scale over time means that environmental
flows should be targeted at high level surfaces (<25 000 MLD-1) that provide long term
sources of carbon to the river channel. Conserving flows of this magnitude will also reinstate
flow variability, an important facet of the Barwon-Darling River?s hydrology that has been
changed by water resource development. The research presented in this thesis highlights the
importance of not only considering pattern and process at multiple scales, but also the way in
which these processes influence landscape patterns over time, leading to the identification of
the appropriate scales that can best be targeted for the conservation of these systems.
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Kharat, Deepak Bhimrao. "Practical aspects of integrated 1D2D flood modelling of urban floodplains using LiDAR topography data." Thesis, Heriot-Watt University, 2009. http://hdl.handle.net/10399/2272.
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Flood risk, a major risk facing mankind today, is projected to aggravate in view of the future predictions pertaining to the assessment of climate change scenarios. Traditionally, flood risk assessment exercises of urban floodplains have been carried out using 1D model as well as 1D model with storage cells. In view of the recent availability of high quality Light Detection and Ranging (LiDAR) topography data, availability of higher computing capacities, developments in the numerical computing techniques and the merits of an integrated 1D2D computing modelling method, integrated 1D2D modelling has gained a momentum for strategic flood risk management (SFRM) and detailed urban flood risk analysis. The research discussed in this thesis evaluates this modelling method using high quality LiDAR data in light of the results from the traditionally used 1D model with storage cells modelling method. The research study was carried out using laboratory experimental observation data, hypothetical urban floodplain data and data for a section of the River Clyde and adjoining urban floodplain in Glasgow, a major city in Scotland, UK. It concludes that, while integrated 1D2D models are of much benefit for a detailed flood risk analysis, specific attention needs to be paid towards the lateral extents of 1D model and the source of the river bank elevations while integrating it with a 2D model, particularly so when such a study is carried out for urban floodplains; and that the high quality LiDAR data significantly facilitates Strategic Flood Risk Modelling (SRFM) of urban floodplains.
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Jayakaran, Anand D. "The formation of benches in agricultural channels in Ohio." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1149002547.
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Dikgola, Kobamelo. "Spatial and temporal variation of inundation in the Okavango Delta, Botswana; with special reference to areas used for flood recession cultivation." University of the Western Cape, 2015. http://hdl.handle.net/11394/4677.
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Philosophiae Doctor - PhDThe Okavango Delta is recognized as one of the famous inland wetlands and its sustainable use is important for socio-economic development of Botswana. The Okavango delta comprises permanent swamps, seasonal swamps, and drylands on islands within the delta and the surrounding areas, sustained by Okavango river inflows from upstream and local rainfall. TheOkavango River splits into several distributary channels within the delta. Areas which are flooded annually vary in response to varying inflows into the delta. Peak inflows into the delta occur during the February to May period. Due to the low gradient over the delta, these inflows move slowly resulting in peak outflows from the delta occurring during the June to August period. The inundated area over the entire delta increases from May until it reaches maximum inAugust and starts to decrease from September, reaching minimum inundated area in the months of December and January. The incoming flood wave into the delta and maximum inundation is out of phase with the local rainfall season.Communities living within and around the delta derive their livelihoods from tourism, hunting, fishing, livestock rearing, and crop production. Crop production is carried out on drylands and within floodplains. Some of the households take advantage of the increase in soil moisture arising from this inundation along floodplains to cultivate their crops as the floods recede. This practice is locally referred to as molapo farming which highly depends on inundation of floodplains. The availability of floodplain inundation highly depends on the magnitude of inflows into the delta and the local rainfall which are highly variable resulting in uncertainty regarding successful crop production, availability of livestock grazing areas, and uncertainty in reliance on the wetlands resources such as fishing. The uncertainty experienced in timing of extreme events which cause flooding of resulting in water reaching areas or floodplains where it is not wanted, and also uncertainity in timing of low flows, therefore water not reaching some parts of the delta.Several hydrological studies have been carried out with the aim of improving the understanding of the spatial and temporal dynamics of flows throughout the delta including predicting areas that are likely to be inundated each year. The significant gap addressed by this research is to improve the understanding of the spatial and temporal influence of magnitude and timing of flows on floodplain inundation. Local rainfall on the delta is highly variable over time and space due to its convective nature. This research also addresses the rainfall temporal and spatial variations and its implications on floodplain inundation. The knowledge about spatial extent and duration of floodplain inundation should assist in predicting each year the viability of molapo farming. Three research site, Shorobe, Tubu and Xobe are selected as case studies to understand the dynamics of floodplain inundation induced either by inflows or local rainfall. Local rainfall during the December to March period enables the crops to reach maturity. The onset of the rainy season is very important in supporting sowing of crop seeds. Local rainfall on the delta varies considerably. Aerial rainfall interpolation shows a change in rainfall magnitudes over space in different rainfall months, i.e different parts of the delta receive different rainfall magnitudes in different months of the rainy season. The spatial variation is mainly associated with the migration of the ITCZ southwards first through East Africa during October andNovember and down over Southern Africa in December to February. The movement of the ITCZ brings rainfall concentration on the northern and eastern parts of the Okavango Delta during December to January and bringing rainfall concentration to the northwestern part of the delta around February. However, rainfall spatial correlation between stations can be poor even within the first 150 km therefore implying neighboring places do not experience floodplain inundation by rainfall at the same time. The poor spatial correlation of rainfall between neighboring stations reflects the erratic nature of rainfall in the Okavango Delta characterised by localized thunderstorms. Change detection shows change points in rainfall which can be associated with ENSO episodes. A change point is identified in 1976 and 1977 which can be associated with the El Nino episodes during those years and two change points identified in 1999 and 2004 which can be associated with the La Nina episodes, therefore rainfall induced floodplain inundation can also be associated with wet and dry ENSO episodes. Rainfall does not show any significant trends except for an increasing trend on 10th percentile of Shakawe rainfall. Rainfall also does not show any cyclic behavior. Rainfall over the Okavango Delta can be divided into three unique homogenious sub-regions; sub-region 1: the northern part following the GEV probability distribution and being the region with highest rainfall amounts; sub-region 2: the lower northern and the outlet parts of the Okavango Delta following the GPA distribution with moderate rainfall; and sub-region 3: the middle part of the delta extending to the western and the eastern fringes of the delta, following the P3 distribution and having the lowest rainfall.The main characteristic that defines the Okavango Delta flows at Mohembo is its cyclic behavior. Three significant cycles are identified, close to 10, 20 and 40 years. No significant trends are identified, only a decreasing trend in minimum flows. Change points are identified in 1979 and 1988 and these can be explained by the existing cyclicity since no major land use changes have taken place in the Okavango River Basin upstream before 1989. The existence of cyclicity in Okavango River flows at Mohembo also explains the periodic wetting and drying of different floodplains in the delta. A long period of low flows was experienced from 1983 until 2003 and floodplain inundation extent was greatly reduced, more especially during the 1993-2003. During the 1993-2003 period, flows could no longer reach Maun Bridge along Thamalakne River, therefore leaving molapo floodplains around Boteti River, Gomoti River and Thaoge River to dry out. The 10 and 40 year return floods are important as they indicate the probability of a flood magnitude which has potential to result in major inundation in the Okavango Delta. Therefore, flood magnitudes with recurrence interval 10 and 40 years have high probability of occurring and can cause major floodplain inundation as they can be above the 2009 flood of 969 m3/s, which was the return of major inundation of Okavango Delta floodplains after a long period of dryness. The Ngoqa-Maunachira distributary channel of the Okavango River receives 32% of flow volumes entering the Okavango Delta at Mohembo. 12 % of the Mohembo flow volumes reach the Jao-Boro distributary whilst 1% is received by the Thaoge distributary. Therefore more inundation is experienced along the Ngoqa-Maunachira system compared to the other two. Only about 2% of the Mohembo flow volumes leave the Okavango Delta through Boteti River. Long term shifting of flow direction amongst reaches along the Okavango Delta distributaries is evident more especially along the Ngoqa-Maunachira River system. This results in shifting of inundation. Sub-surface water respond significantly to local rainfall and inflows with high soil moisture conditions retained at 60 cm and 100 cm below the ground.
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Jung, Kwansue 1959. "The comparative sediment processes in channel and overbank." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277205.
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The question posed in this study is why alluvial soil on a floodplain is finer than the bed material of the river that supplied the sediments deposited to form the floodplain. A schematic, simplified river/floodplain system is used in an approximate analysis to find the size distribution of the floodplain soil. It is assumed that the stable limiting condition is a suspended load in the floodplain flow of the same concentration and composition as the sediment load in that portion of the river channel flow above the level of the floodplain. It was found that floodplain soil should be finer than the channel bed material; how much finer depending on the bank height, and to a lesser degree the width of the floodplain.
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Necsoiu, Dorel Marius. "A Data Fusion Framework for Floodplain Analysis using GIS and Remotely Sensed Data." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2557/.
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Throughout history floods have been part of the human experience. They are recurring phenomena that form a necessary and enduring feature of all river basin and lowland coastal systems. In an average year, they benefit millions of people who depend on them. In the more developed countries, major floods can be the largest cause of economic losses from natural disasters, and are also a major cause of disaster-related deaths in the less developed countries. Flood disaster mitigation research was conducted to determine how remotely sensed data can effectively be used to produce accurate flood plain maps (FPMs), and to identify/quantify the sources of error associated with such data. Differences were analyzed between flood maps produced by an automated remote sensing analysis tailored to the available satellite remote sensing datasets (rFPM), the 100-year flooded areas "predicted" by the Flood Insurance Rate Maps, and FPMs based on DEM and hydrological data (aFPM). Landuse/landcover was also examined to determine its influence on rFPM errors. These errors were identified and the results were integrated in a GIS to minimize landuse / landcover effects. Two substantial flood events were analyzed. These events were selected because of their similar characteristics (i.e., the existence of FIRM or Q3 data; flood data which included flood peaks, rating curves, and flood profiles; and DEM and remote sensing imagery.) Automatic feature extraction was determined to be an important component for successful flood analysis. A process network, in conjunction with domain specific information, was used to map raw remotely sensed data onto a representation that is more compatible with a GIS data model. From a practical point of view, rFPM provides a way to automatically match existing data models to the type of remote sensing data available for each event under investigation. Overall, results showed how remote sensing could contribute to the complex problem of flood management by providing an efficient way to revise the National Flood Insurance Program maps.
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Lind, Pollyanna 1970. "Holocene Floodplain Development of the Lower Sycan River, Oregon." Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/10171.
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xv, 203 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.Water and pumice accumulated behind a dam that, upon failure, scoured the c1aydominated floodplain and deposited pumice sands across the Sycan Valley. The pumice originated from the eruption of Mount Mazama (approximately 7660 ybp), and dam failure occurred very shortly afterwards. In response to the flood the lower Sycan River underwent episodes of channel aggradation and degradation. This study presents the history of channel evolution for the lower Sycan River from 11,000 years ago to present, based on floodplain stratigraphy and radiocarbon chronology. Seven primary periods of channel and floodplain development are identified: I. Early Holocene Dynamic Equilibrium; II: Sycan Outburst Flood; III. Initial Channel Formation; IV. Degradation & Widening; V. Aggradation & Lateral Migration; VI. (Secondary) Degradation & Widening; VII. Modern Dynamic Equilibrium. The active floodplain of the modern lower Sycan River is flanked by terraces of the rapidly abandoned Sycan Outburst Flood deposits.
Committee in Charge: Dr. Patricia McDowell, Chair; Dr. Jim E. O'Connor; Dr. Andrew Marcus
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Potter, Karen. "Battle for the floodplains : an institutional analysis of water management and spatial planning in England." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/11853/.
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Dramatic flood events witnessed from the turn of the century have renewed political attention and, it is believed, created new opportunities for the restoration of functional floodplains to alleviate the impact of flooding on urban development. For centuries, rural and urban landowning interests have dominated floodplains and water management in England, through a ‘hegemonic discourse alliance’ on land use development and flood defence. More recently, the use of structural flood defences has been attributed to the exacerbation of flood risk in towns and cities, and we are warned if water managers proceeded with ‘business as usual’ traditional scenarios, this century is predicted to see increased severe inconveniences at best and human catastrophes at worst. The novel, sustainable and integrated policy response is highly dependent upon the planning system, heavily implicated in the loss of floodplains in the past, in finding the land for restoring functioning floodplains. Planners are urged to take this as a golden opportunity to make homes and businesses safer from flood risk, but also to create an environment with green spaces and richer habitats for wildlife. Despite supportive changes in policy, there are few urban floodplain restoration schemes being implemented in practice in England, we remain entrenched in the engineered flood defence approach and the planner’s response is deemed inadequate. The key question is whether new discourses and policy instruments on sustainable, integrated water management can be put into practice, or whether they will remain ‘lip-service’ and cannot be implemented after all. Against the backdrop of a broader modernity debate, in this thesis the English floodplain emerges as a ‘battle site’ where the planner is caught in the cross fire of an ideological clash between economic (armed with technology) and environmentalist (allied with nature) arguments and preferred change in land use. Furthering interpretative research and discourse analysis to tap and explain belief and knowledge systems rather than rational ‘fluvial systems’ per se, the thesis delves deeper than previous research, into the mind sets and ‘irrationalities’ of actors’ practices on the floodplain. The policy response advocating ‘making space for water’ and floodplain restoration is based on an overstretched steering optimism, and will continue to prove too radical if the mediating and tempering political-institutional context is not seriously addressed. If there is true commitment from the UK government, closing the current implementation deficit on floodplain restoration will require the recognition and amelioration of persisting power structures within government agencies, founded on technological and economic rationalities, and permit the planner to share responsibility, unfettered by one sided growth objectives, to find new ways of working across sectors and disciplines towards sustainable, water sensitive towns and cities.
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Ismail, Zulhilmi. "A study of overbank flows in non-vegetated and vegetated floodplains in compound meandering channels." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/7905.
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Laboratory experiments concerning stage-discharge, flow resistance, bedforms, sediment transport and flow structures have been carried out in a meandering channel with simulated non-vegetated and vegetated floodplains for overbank flow. The effect of placing solid blocks in different arrangements as a model of rigid, unsubmerged floodplain vegetation on a floodplain adjacent to a meandering channel is considered. The aim was to investigate how density and arrangements of floodplain vegetation influence stage-discharge, flow resistance, sediment transport and flow behaviours. Stage-discharge curves, Manning's n and drag force FD are determined over 165 test runs. The results from the laboratory model tests show that the placing of solid blocks along some part of the bend sections has a significant effect on stage-discharge characteristics. The change in stage-discharge by the blocks is compared using different arrangements, including the non-vegetated floodplains case. The experimental results show that the presence of energy losses due to momentum exchange between the main channel and the floodplain as well as the different densities of the blocks on a floodplain induce additional flow resistance to the main channel flow, particularly for shallow overbank flows. In general, the results show that the density and arrangement of blocks on the floodplains are very important for stage-discharge determination and, in some cases, for sediment transport rates, especially for a mobile main channel. Also, the correction parameter, a is introduced in order to understand the effects of blocks and bedforms on the force balance equation. By applied the correction factor c; a stagedischarge rating curve can be estimated when the avalue is calibrated well. Telemac 2D and 3D were applied to predict mean velocity, secondary flow and turbulent kinetic energy. Telemac computations for non-vegetated and vegetated floodplain cases in a meandering channel generally give reasonably good predictions when compared with the measured data for both velocity and boundary shear stress in the main channel. Detailed analyses of the. predicted flow variables were therefore carried out in order to understand mean flow mechanisms and secondary flow structures in compound meandering channels. The non-vegetated and two different cases of vegetated floodplain for different relative depths were considered. For the arrangement on a non-vegetated floodplain shows how the shearing of the main channel flow as the floodplain flow plunges into and over the main channel influences the mean and turbulent flow structures, particularly in the cross-over region. While applying vegetated floodplain along a cross-over section confirmed that the minimum/reduction shearing of the main channel flow by the floodplain flow plunging into and over the main channel is observed from the cross-sectional distributions of the streamwise velocity (U), lateral velocity (V), and secondary flow vectors. In addition to that, the vegetated floödplain along the apex bend region shows a small velocity gradient within the bend apex region. However, strong secondary flow in the cross-over section suggested that the flow interaction was quite similar to the non vegetation case in the cross-over section region.
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Franklin, Louise Bartlett. "Floodplain management in Georgia : its techniques, funding, and program design." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/20802.
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Natho, Stephanie [Verfasser], Gunnar [Akademischer Betreuer] Nützmann, Mathias [Akademischer Betreuer] Zessner, and Dagmar [Akademischer Betreuer] Haase. "Modelling nutrient retention in floodplains : development of a concept to empirically derive the average inundated floodplain extent and incoming nutrient loads / Stephanie Natho. Gutachter: Gunnar Nützmann ; Mathias Zessner ; Dagmar Haase." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2013. http://d-nb.info/1044956267/34.
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