Dissertations / Theses: 'Floodplain ecology'

1

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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2

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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3

Milne, Judith May. "Plant community ecology of a major subtropical riverine floodplain." Thesis, University of Glasgow, 2004. http://theses.gla.ac.uk/4057/.

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This project described the vegetation of a stretch of the Parana River and investigated which natural or human-imposed factors might be controlling its characteristics, its capacity for biodiversity support and its potential to provide an economic resource. This information is of value in the planning of management strategies aiming to conserve biodiversity and develop sustainable ways in which the floodplain resources can be utilised. Central to this study were the surveys of vegetation and environmental characteristics of aquatic, terrestrial and transitional habitats of the Parana floodplain near Porto Rico. These produced extensive data sets which helped to reveal the types of vegetation-environment relationships structuring the floodplain plant communities. To complement this investigative approach, three aspects of the functioning of floodplain vegetation were chosen for closer study. These were the impacts of livestock grazing on wetland and island vegetation, competitive interactions between pairs of free-floating aquatic plant species and the role of aquatic macrophytes in contributing carbon to aquatic food webs. Three major community types were identified in the aquatic habitats of the floodplain, one which included Eichhornia azurea in mixture with several free-floating and emergent species, a second in which E. azurea was strongly dominant and a third comprised purely of submerged species. Two strongly contrasting broad vegetation communities were identified at bank and shore environments. Polygonum and Ludwigia species were important in one group and Poaceae, creepers, woody plants and ferns in the other group. Sub-groups of these communities could also be suggested, but these are less distinct. Most of the floodplain sites supported a Poaceae-creeper community type with the remaining sites supporting a community indicated by Polygonum species. The Poaceae group was comprised of a number of sub-communities in which the importance of Poaceae relative to other species varied. The aquatic vegetation communities differed structurally with contrasting community biomass, canopy height, canopy cover, species richness and stem density. They were associated with waterbodies with different water depth and pH and different sediment nitrogen and phosphorus contents. Water flow rate category and underwent light availability also differed between the sites that tended to support the different vegetation types. The two major bank and shore vegetation communities differed in canopy cover, in the soil nitrogen, phosphorus and calcium levels with which they were associated and in the steepness of the bank on which they tended to grow. Floodplain vegetation communities contrasted in species richness and differed in the soil nitrogen and calcium levels and river systems with which they were associated.

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4

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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5

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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6

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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7

Soong, Oliver. "Vegetation Establishment Following Floodplain Restoration in Mediterranean-climate California." Thesis, University of California, Santa Barbara, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10254066.

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Although herbaceous communities are important components of floodplain ecosystems, the factors constraining their restoration and post-restoration dynamics are poorly understood. Over the decade following restoration of a 3.2 km reach of the Merced River and floodplain in California, we tracked herbaceous community composition to distinguish floodplain habitats and utilized perturbations from revegetation treatments and post-restoration flooding to generate community assembly rule hypotheses regarding treatment effectiveness and persistence, with a particular interest in native perennials capable of suppressing non-natives over time if undisturbed. Revegetation treatments comprised combinations of sowing a sterile cover crop, sowing native species, and inoculating mycorrhizae. Most surveyed floodplain areas comprised a low terrace characterized by exceptionally droughty soils, relatively deep groundwater, and occasional flooding lasting into summer. Few species could tolerate both flood and drought to this extent, and the flood year community was generally distinct from that in non-flood years. Both communities were dominated by ruderals capable of avoiding stress and re-establishing following disturbance, including many non-native annual grassland species. Only Artemisia douglasiana responded to the treatments, as most seeded native species failed to establish, including those native perennial grasses expected to suppress non-native annuals, while other seeded native species either established adequately from natural dispersal or failed to persist through moderate flooding. Neither the cover crop nor mycorrhizal inoculation had any meaningful effect. Restoration efforts in naturally ruderal-dominated habitats may be better spent allowing natural regeneration, addressing particularly noxious invasives, and identifying or constructing habitats supporting long-lived native perennials.

Although originally developed for population sizes and population growth rates, modern capture-recapture models can estimate demographic rates in complex situations: multistate models for multiple study sites and stage-structured populations, superpopulation entry probability models for recruitment, and multievent models when state assessments are uncertain. However, combinations of these complications, such as recruitment studies with uncertain state assessments, are common, yet no single model has explicitly incorporated all of these elements. Ultimately, these models estimate the same fundamental population process with the same general approach, and we combine them in a generalized hidden process model based upon a simple discrete state and transition population model with Poisson recruitment that can estimate how recruitment and survivorship rates vary with respect to measured covariates from uncertain state assessments for a stage-structured population at multiple sites. Although closely related to the motivating models, the generalized model relaxes the Markov assumption. While we provide the distributions necessary to implement Bayesian data augmentation methods, we also provide an efficient analytical likelihood with a compact parameter space that is applicable in the absence of density-dependent mortality. As a demonstration, we estimate the influence of several covariates on recruitment and survivorship rates from uncertain observations of Salix gooddingii seedlings at different locations along a riparian gradient, and we use simulations to examine variation in the precision of estimated parameters.

In Mediterranean climates, cottonwoods and willows often exhibit high germination and seedling mortality rates, with recruitment occurring primarily in the occasional year when favorable spring floods improve survivorship. However, along the Robinson Reach of the Merced River, both germination and mortality rates appeared to be atypically low. To understand why these rates were so low along this recently restored flow-regulated, gravel-bedded stream, we surveyed Populus fremontii, Salix exigua, and Salix gooddingii, estimated germination and survivorship rates, and examined their correlations with factors expected to constrain recruitment, namely seed release, seed arrival, moist germination beds, light levels, groundwater depth, groundwater recession rates, and shear stress. Germination/initial establishment rates were low due in part to low seed arrival rates. Only Salix gooddingii was abundant enough to model in detail, and while moist germination surfaces increased germination/initial establishment, rates were low overall. Survivorship rates for Salix gooddingii seedlings and for small individuals were not correlated with any examined covariates. Seedlings tolerated moderate competition, and the absence of major scouring, even during 6 year flows, enabled survival at sites with sufficiently shallow groundwater that seedlings were unaffected by groundwater recession rates.

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8

Dick, David Allen. "Spatial heterogeneity of soil nutrients, nitrogen dynamics and vegetation in a 3rd order stream floodplain in southwestern West Virginia." Huntington, WV : [Marshall University Libraries], 2003. http://www.marshall.edu/etd/descript.asp?ref=339.

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Thesis (M.S.)--Marshall University, 2003.
Title from document title page. Document formatted into pages; contains ix, 140 p. including illustrations. Includes vita. Includes bibliographical references (p. 104-108).

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9

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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Abstract:

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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10

Kreibich, Heidi. "N₂ fixation and denitrification in a floodplain forest in central Amazonia, Brazil." Connect to this title online (Marburg Universität site) Connect to this title online (Deutsche Nationalbibliothek site), 2002. http://archiv.ub.uni-marburg.de/diss/z2002/0398/.

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11

Hughes, F. M. R. "The Tana River floodplain forest, Kenya : ecology and the impact of development." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305892.

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12

Laaker, Dillan J. "Avian Use of Floodplain Forest Communities along the Upper Mississippi River." Thesis, Southern Illinois University at Edwardsville, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10808741.

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Floodplain forests along the Upper Mississippi River are known to provide valuable habitat for many species of migrating songbirds, including the Cerulean Warbler (Setophaga cerulea) and other species of concern. The forested islands of the confluence region where the Illinois and Missouri Rivers join the Mississippi vary greatly in their structure and composition, providing a variety of habitats for migrating bird species. While past studies have looked at the richness and diversity of bird species across gradients of forest structure, very few have determined which species are characteristic of certain forest types. Effective management and conservation of these lands by state and federal agencies requires that managers understand patterns of species use in these different forest communities. The objectives of this study were (1) to discover how bird community composition varies throughout the floodplain, (2) to determine which vegetation factors, structural or floristic, influence the composition of bird communities, and (3) to identify any species indicative of certain habitat types. Using a protocol developed through a partnership with the U.S. Army Corps of Engineers—St. Louis District, the Audubon Center at Riverlands, and the Cornell Lab of Ornithology, 10 minute avian point count surveys were conducted from May 15 – June 30 at 95 survey points located throughout the forested areas of the Upper Mississippi River floodplain. Data collected during the 2017 surveys were added to point count data from the 2015 and 2016 survey seasons. An invaluable tool developed by the U.S. Army Corps of Engineers’ forestry division, the Forest Management Geodatabase (FMG) was used to analyze structural complexity and vegetation characteristics at each avian point count site, including canopy height, basal area, tree species richness, and understory height. Differences in bird species richness across values of canopy height, basal area, understory height, and tree species richness were explored and tested using single-factor ANOVA. Non-metric multidimensional scaling (NMDS) was used to summarize the pattern of avian community composition among sites and analysis of similarities (ANOSIM) tested for differences in avian communities among forest types. Bird species richness did not differ significantly across values of any of the four forest variables tested. NMDS and ANOSIM found that both canopy height and basal area significantly affected bird community composition while tree species richness and understory height had no effect. Indicator species analysis was then used to identify those species that characterized certain categories of canopy height and basal area. Indicator species analysis found 21 species to be indicators across four discreet categories of canopy height and 23 species to be indicators across 4 categories of basal area. Indicator species of note included five focal species: Indigo Bunting, Prothonotary Warbler, American Redstart, Warbling Vireo, and Red-shouldered Hawk. Warbling Vireos were indicators for sites with canopy heights less than 9 meters, while Prothonotary Warblers were characteristic of sites with the largest values of basal area (> 75 m²/ha). These focal species are chosen by the Audubon Center at Riverlands and are deemed important to the region or species of concern, making them targets of conservation. The knowledge of bird species-habitat relationships gained from this study is critical for the successful management of floodplain forest in order to benefit Neotropical migratory bird species on the Upper Mississippi River System.

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13

George, Amy Kathryn. "Eucalypt regeneration on the Lower Murray floodplain, South Australia." Connect to this title online, 2004. http://hdl.handle.net/2440/37706.

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Vegetation along the River Murray floodplains has been shown to be in a severe state of decline. This decline is amplified by the impositions of river regulation. In South Australia, where vegetation losses have been great, regeneration is limited and may result in not only individual tree losses but also widespread population decline. This study aimed to examine the relationship between river flows and the regeneration process in populations of Eucalyptus camaldulensis and Eucalyptus largiflorens. The current structure of the populations was examined to determine if a viable number of varying age-classed trees were present. Tree surveys conducted at Banrock Station determined that while densities were low for both species, E. camaldulensis had a more sustainable population structure than E. largiflorens. Growth stages for both species illustrated highly clumped distribution, which is believed to correspond with river flooding magnitudes and frequencies. To address the potential link between tree distribution and flooding within the River Murray, a hydrological analysis was conducted for Banrock Station using river flows at the South Australian border from 1900 to 2003. The amount of time growth stages for each species were inundated was found to be greatly reduced under regulated flows compared to natural flows. This has resulted in shifted localized regeneration patterns corresponding with E. camaldulensis' greater demand for inundation than E. largiflorens. Moderate magnitude flows have been most impacted by regulation, and consequently these are the very flows needed for floodplain tree population maintenance. Flowering and seed fall for E. camaldulensis and E. largiflorens were monitored at Banrock Station for 22 months to identify losses in reproductive potential resulting from tree decline. While seed viability was not affected by vigour, trees with visually reduced vigour were found to produce less fruit and had reduced seed fall, as well as a reduced rate of fruit development. Dendrochronological techniques were applied to floodplain trees. Age and size relationships could be established, implying that such techniques can be applied in South Australia to high quality sites. Growth responses within cohorts were similar and easily matched between individuals illustrating cyclic, but not necessarily seasonal correlations. This work verified the preferential selection of younger trees for dendroecological studies, and identified a relationship between on moderate flows and measurable girth expansion in both floodplain tree species.
Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2004.

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14

Florentine, Singarayer K. "Ecology of Eucalyptus victrix in grassland in the floodplain of the Fortescue River." Thesis, Curtin University, 1999. http://hdl.handle.net/20.500.11937/2105.

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The WA coolibah tree, Eucalyptus victrix L. Johnson & K. Hill forms an unique and pristine woodland in the Fortescue Valley, in the Pilbara district of Western Australia. Until recently, no research had been done on E. victrix ecology and concern had been expressed by pastoral managers and others about the condition of the woodland occupied by this species. This research was an attempt to understand the ecology of coolibah using a multi-disciplinary approach.A population demographic study of stands in E. victrix woodland reveals that the present tree populations occupy larger areas than saplings and seedlings. Soil moisture and warm summer temperatures are believed to be stimulating factors for seedling recruitment of E. victrix. Different size classes (height/diameter) reflect different recruitment events and these reflect past availability of seeds and adequate soil moisture in that particular area of the woodland. Occasional grasshopper outbreaks and drought cause canopy shrinkage. Presence of hollow boles, restrict dendrochronological examination of tree ages.An important population study was of a post-seedling cohort at Roy Hill, where height distribution reflected a typical single recruitment event. In subsequent years (1995 - 1998) height measurement showed several peaks, suggesting that seedlings were now growing at different rates. Uniform and steady height growth was observed on saplings found at the edges of gilgai. During May 1998 several saplings flowered, it was assumed that E. victrix attained its reproductive maturity at mean height of 2.50 m and with a stem diameter of 50 mm.Seedling recruitment and subsequent growth mainly depend on heavy rainfall flooding events. Seedling recruitment occurs only from current seed rain. Seed longevity reduces after 54 days of burial at 50 mm depth. Mortality (4 - 6 leaf stage) of newly recruited seedlings during subsequent dry months is very high. Furthermore, allelopathic effects (root competition from established grass and insect herbivory) are additional causes of seedling mortality in the years of recruitment.Seedlings recruited at a burnt (disturbed) site, grew faster compared with undisturbed sites with less mortality. This suggested that fire created a suitable condition by reducing root competition, increasing soil nutrients and also creating a gap which providing sufficient solar radiation for seedlings to establish and develop into a healthy population. It is suggested that once newly recruited seedlings overcome the first summer, mortality rates during subsequent years are drastically reduced.Long-term waterlogging of E. victrix seedlings significantly increases seedling stem diameter. Large numbers of adventitious roots are developed and lenticels proliferate on the submerged portion of the stem. Flooding reduces each photosynthesis, transpiration and stomatal conductance. Flooding does not increase shoot fresh or dry weight on 4-, 8- or 17- week old seedlings. Leaf emergence may be stimulated on flooded seedlings compared with unflooded seedlings. While root dry weight is greater in 17-week old flooded plants than 13 - week seedlings, this difference is not significant. It is suggested that maintenance of a high root/shoot ratio is a drought adaptation. Furthermore, comparative study of flood tolerance in semi-arid eucalypt species suggests that those species intolerant of flooding seldom express morphological adaptations and fail to recover from physiological damage.The annual grass Setaria dielsii occurs under the canopy of mature E.victrix trees of the coolibah woodland. This species has probably displaced more palatable perennial grasses. Soil moisture under trees is slightly higher and soil temperatures are less extreme than away from the canopy. Growth of S. dielsii appears to be more associated with soil nutrient status. Levels of total N, Mg, K, and of electrical conductivity (EC) under trees are significantly higher than those away from the tree. Levels of Ca, Na, Fe, and organic carbon do not differ. The under story sub-shrub Malvastrum americanum is an important competitor with S. dielsii. Light availability may determine relative biomass contributions of the two species.The effect of the density of grass species, growing space and time of establishment on E. victrix seedlings (inter-specific competition), and the effect of density and growing space within E. victrix seedling populations (intra-specific competition) were studied under controlled conditions. Results indicate resources necessary for growth of individual E. victrix seedlings were more limiting under increase density of neighbouring grass species than under intra-specific competition. In particular photosynthetic area was drastically reduced in mixed culture.Lack of ground cover beneath the canopy of isolated E. victrix trees was ascribed to toxic or phenolic substances present in leaf, bark and leaf litter of E. victrix. Lactuca sativa seed germination subjected to extracts and leachate demonstrate that the fresh leaf of E. victrix possesses toxic substances which cause deleterious effects on both germination and radicle development. Similarly, increasing concentrations of leaf and bark leachate show reduced germination percentage of L. sativa seeds. Shoot and root biomass of grass and eucalyptus treated with leaf leachate were reduced. E. victrix leaf leachate significantly reduced shoot and root biomass of its own seedlings. High Performance Liquid Chromatogram (HPLC) analysis separated 11 and 8 possible toxic substances from leaf and bark extract respectively.

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15

Florentine, Singarayer K. "Ecology of Eucalyptus victrix in grassland in the floodplain of the Fortescue River." Curtin University of Technology, School of Environmental Biology, 1999. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=10260.

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The WA coolibah tree, Eucalyptus victrix L. Johnson & K. Hill forms an unique and pristine woodland in the Fortescue Valley, in the Pilbara district of Western Australia. Until recently, no research had been done on E. victrix ecology and concern had been expressed by pastoral managers and others about the condition of the woodland occupied by this species. This research was an attempt to understand the ecology of coolibah using a multi-disciplinary approach.A population demographic study of stands in E. victrix woodland reveals that the present tree populations occupy larger areas than saplings and seedlings. Soil moisture and warm summer temperatures are believed to be stimulating factors for seedling recruitment of E. victrix. Different size classes (height/diameter) reflect different recruitment events and these reflect past availability of seeds and adequate soil moisture in that particular area of the woodland. Occasional grasshopper outbreaks and drought cause canopy shrinkage. Presence of hollow boles, restrict dendrochronological examination of tree ages.An important population study was of a post-seedling cohort at Roy Hill, where height distribution reflected a typical single recruitment event. In subsequent years (1995 - 1998) height measurement showed several peaks, suggesting that seedlings were now growing at different rates. Uniform and steady height growth was observed on saplings found at the edges of gilgai. During May 1998 several saplings flowered, it was assumed that E. victrix attained its reproductive maturity at mean height of 2.50 m and with a stem diameter of 50 mm.Seedling recruitment and subsequent growth mainly depend on heavy rainfall flooding events. Seedling recruitment occurs only from current seed rain. Seed longevity reduces after 54 days of burial at 50 mm depth. Mortality (4 - 6 leaf stage) of newly recruited seedlings during ++
subsequent dry months is very high. Furthermore, allelopathic effects (root competition from established grass and insect herbivory) are additional causes of seedling mortality in the years of recruitment.Seedlings recruited at a burnt (disturbed) site, grew faster compared with undisturbed sites with less mortality. This suggested that fire created a suitable condition by reducing root competition, increasing soil nutrients and also creating a gap which providing sufficient solar radiation for seedlings to establish and develop into a healthy population. It is suggested that once newly recruited seedlings overcome the first summer, mortality rates during subsequent years are drastically reduced.Long-term waterlogging of E. victrix seedlings significantly increases seedling stem diameter. Large numbers of adventitious roots are developed and lenticels proliferate on the submerged portion of the stem. Flooding reduces each photosynthesis, transpiration and stomatal conductance. Flooding does not increase shoot fresh or dry weight on 4-, 8- or 17- week old seedlings. Leaf emergence may be stimulated on flooded seedlings compared with unflooded seedlings. While root dry weight is greater in 17-week old flooded plants than 13 - week seedlings, this difference is not significant. It is suggested that maintenance of a high root/shoot ratio is a drought adaptation. Furthermore, comparative study of flood tolerance in semi-arid eucalypt species suggests that those species intolerant of flooding seldom express morphological adaptations and fail to recover from physiological damage.The annual grass Setaria dielsii occurs under the canopy of mature E.victrix trees of the coolibah woodland. This species has probably displaced more palatable perennial grasses. Soil moisture under trees is slightly higher and soil temperatures are less extreme than away from the canopy. Growth of ++
S. dielsii appears to be more associated with soil nutrient status. Levels of total N, Mg, K, and of electrical conductivity (EC) under trees are significantly higher than those away from the tree. Levels of Ca, Na, Fe, and organic carbon do not differ. The under story sub-shrub Malvastrum americanum is an important competitor with S. dielsii. Light availability may determine relative biomass contributions of the two species.The effect of the density of grass species, growing space and time of establishment on E. victrix seedlings (inter-specific competition), and the effect of density and growing space within E. victrix seedling populations (intra-specific competition) were studied under controlled conditions. Results indicate resources necessary for growth of individual E. victrix seedlings were more limiting under increase density of neighbouring grass species than under intra-specific competition. In particular photosynthetic area was drastically reduced in mixed culture.Lack of ground cover beneath the canopy of isolated E. victrix trees was ascribed to toxic or phenolic substances present in leaf, bark and leaf litter of E. victrix. Lactuca sativa seed germination subjected to extracts and leachate demonstrate that the fresh leaf of E. victrix possesses toxic substances which cause deleterious effects on both germination and radicle development. Similarly, increasing concentrations of leaf and bark leachate show reduced germination percentage of L. sativa seeds. Shoot and root biomass of grass and eucalyptus treated with leaf leachate were reduced. E. victrix leaf leachate significantly reduced shoot and root biomass of its own seedlings. High Performance Liquid Chromatogram (HPLC) analysis separated 11 and 8 possible toxic substances from leaf and bark extract respectively.

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16

Joyce, Christopher Brian. "Management of European floodplain grasslands for plant biodiversity." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/6988.

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European floodplain grasslands are characterized by periodic flooding and regular management, usually cutting and grazing as part of an agricultural system. Past losses and ecological degradation have been due largely to river regulation and either agricultural intensification or abandonment and have resulted in a substantial reduction in area across Europe. Nevertheless, the remaining resource supports considerable biodiversity and a high level of biological production. A better quantitative understanding of the functioning of these grasslands is required in order to establish effective conservation management within a sustainable land use system. The thesis examines the impact of key management factors on three important functional characteristics of the biodiversity of floodplain plant communities, namely plant diversity (measured by species diversity), cover (%) and primary production (above-ground biomass), on two floodplain grasslands of the River Trent, UK and a third on the the Luznice river, the Czech Republic. Field investigations of the effects of cutting, grazing, cessation of management, the influence of floodborne litter, and the impact of fertilizer nitrogen were undertaken over periods of between one and three seasons. These demonstrated that floodplain grassland plant communities are sensitive to variations in management and that impacts on communities are mediated particularly through effects on plant competition. Productive competitive species were encouraged both by abandonment and fertilizer application whereas cutting and grazing management, and the imposition of litter, favoured stress-tolerating perennials. Species diversity decreased both with high inputs of litter and additions of fertilizer. Plant community responses and competitive strategies of key species are discussed in the context of biodiversity conservation, ecological restoration and management of European floodplain grasslands.

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17

van, der Merwe Jorista. "Ecology of the marsh rice rat (Oryzomys palustris) in southern Illinois: wetland dynamics, metapopulations, and trophic position." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/dissertations/974.

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Wetlands occurring on natural river floodplains typically have more dynamic hydrology, because of influences from the river, than man-made wetlands or those associated with reclaimed minelands. For wetland-associated species, fluctuating water levels can affect patch availability, connectivity and potentially habitat quality, and therefore drive metapopulation dynamics. Differences in hydrology between wetland complexes could change food webs and consequently the trophic diversity of the communities occupying these areas. My first objective was to assess the spatial and temporal variation in occupancy and turnover rates of a semi-aquatic small mammal at 2 hydrologically distinct wetland complexes over 3 years in southern Illinois. My second objective was to determine spatio-temporal variation in the trophic structure of small mammals at 2 wetland complexes (floodplain and mineland) in southern Illinois. To address my first objective, I live-trapped marsh rice rats (Oryzomys palustris) during 2011-2013 at 9 wetland patches on the Mississippi River floodplain and 14 patches at a reclaimed mineland. I used multi-season occupancy modeling to estimate initial occupancy, detection, colonization and extinction rates. Catch per unit effort differed markedly between the 2 sites (27 captures/1,000 trap-nights at the floodplain site vs. 8 at the mining site). Estimates of detection probability increased with an increase in effort (number of traps per night per wetland patch). Occupancy probability was similar between sites and positively related to patch size. Patch colonization probability at both sites was related negatively to total rainfall 3 weeks prior to trapping. In addition, the variation in colonization probability among years, was different between sites, with colonization in 2013 being much lower at the mining site than at the floodplain. An increase in total rainfall 3 months prior to trapping led to a substantial increase in extinction probability on the floodplain, but not at the mining site. Differences in metapopulation dynamics and relative abundance between the 2 sites can be attributed to differences in hydrology and habitat quality. Although rice rats were present at the mining site in much lower numbers than at the floodplain site, these less-natural wetland complexes might serve as valuable refuges for species occurring in increasingly fragmented landscapes. For my second objective, I collected hair samples from 6 species of small mammals (n = 416) occurring at these wetland complexes. I analyzed C and N stable isotopes for 3 mammal taxa (Oryzomys palustris, Peromyscus spp,, Microtus ochragaster) to compare diet between species, sites, and, times. Food sources (vegetation and invertebrates) were collected at each site to form the isotopic baseline. Using stable isotope mixing models, I found no seasonal difference in diet composition, but signatures varied between sites. Oryzomys palustris at both wetland complexes incorporated primarily (70-80%) invertebrates in their diet, and used more C4 vegetation (30%) than C3 (0%). Isotope signatures of Peromyscus diets at the floodplain site were similar to that of Oryzomys, with ~80% invertebrates and >C4 vegetation than C3 vegetation (~20% and 0%, respectively). At the mining site, Peromyscus were at a much lower trophic level and consumed 70% vegetation with C3 plants making up a greater part of their diet than C4 vegetation (50% and 20%, respectively). Microtus was at a lower trophic position than the other 2 species at both sites. These isotope results point to reduced niche overlap between Oryzomys and Peromyscus at the mining site, perhaps due to lower habitat quality and limited suitable resources. Although small mammals had narrower diet breadths at the mining site, none of the species was at a higher trophic position at the mining site than at the floodplain site. At the floodplain site, the more dynamic hydrology might have given rise to higher biodiversity and consequently provided more resources to allow small mammals to use similar food items.

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Morris, Michael Roger. "The contribution of spawning pacific-salmon to nitrogen fertility and vegetation nutrition during riparian primary succession on an expansive floodplain of a large river." Diss., [Missoula, Mont.] : The University of Montana, 2008. http://etd.lib.umt.edu/theses/available/etd-09302008-151352/.

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King, Alison Jane 1974. "Recruitment ecology of fish in floodplain rivers of the southern Murray-Darling Basin, Australia." Monash University, Dept. of Biological Sciences, 2002. http://arrow.monash.edu.au/hdl/1959.1/8391.

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Buckley, Simon. "Investigating the interactions between fluvial processes and floodplain forest ecology in the Amazon Basin." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/18414.

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Amazonian tropical forests account for 20-50% of global primary productivity and up to 40% of carbon stored in terrestrial biomass (Phillips et al., 1998). The Amazon is also home to the Earth’s largest river system, accounting for approximately 20% of the world’s total river discharge (Richey et al., 1989). Despite the clear global significance of the Amazon basin, substantial uncertainties remain in terms of both aboveground wood biomass and carbon storage within its extensive forests (Houghton et al., 2001), and the functioning of its river systems, particularly in terms of floodplain inundation (Wilson et al., 2007). This thesis addresses the aforementioned uncertainties through providing new insight into the interaction between fluvial processes and Amazonian floodplain varzea forests, for the Beni floodplain in north east Bolivia. Flood inundation dynamics for the Beni floodplain are quantified through application of a 1D-2D hydraulic model code, with topographical forcing provided through bare earth DEMs derived from the SRTM global elevation dataset (Farr and Kobrick, 2000). Subsequently, in the final part of the thesis, aboveground wood biomass estimates are generated for the Beni floodplain, through extrapolation of plot scale inventory measurements with respect to spatially distributed remote sensing datasets. These estimates are subsequently integrated with modelled flood inundation and maps depicting Beni river channel migration, in order to explore the influence which fluvial processes exert upon aboveground wood biomass storage in varzea forest stands. Overall, results presented within this thesis quantitatively demonstrate that fluvial processes, specifically flood inundation and lateral channel migration, exert significant impacts upon aboveground biomass storage within Beni floodplain forests. Furthermore, as a result of these influences, aboveground wood biomass storage within Beni floodplain forests is substantially lower than would be expected based upon published estimates for varzea forests across the Amazon (Baker et al., 2004; Saatchi et al., 2007). This implies that systematic overestimation of aboveground wood biomass storage for Amazonian varzea forests may constitute a significant source of uncertainty in basin scale biomass estimates.

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21

Kirby, Jason Robert. "Holocene floodplain vegetation dynamics and sea-level change in the lower Aire valley, Yorkshire." Thesis, University of Hull, 1999. http://hydra.hull.ac.uk/resources/hull:3964.

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Perimarine river valleys are a rich resource for studying palaeoecological change which may provide information concerning catchment and sea-level change. This thesis reconstructs the environmental history of the lower Aire valley during the Holocene, and investigates the factors influencing floodplain and vegetational development.Reconstruction of environmental change in the lower Aire valley in the mid- to late-Holocene is based on lithological and palaeoecological records from three sites in the upper, middle, and lower parts of the study reach. Techniques used include pollen, diatom, wood macrofossil, loss on ignition, and radiocarbon analysis.Paludification of the valley floor was time transgressive, apparently responding to gradually rising sea level, beginning at c. 7000 BP (c. 8000 to c. 7600 cal. yrs BP) at the lowermost site, whereas conditions were not wet enough for preservation of organic sediment in the upper reach until c. 4200 BP (c. 5000 to c. 8500 cal. yrs BP). Accumulation of floodplain peat was interrupted by the deposition of finely laminated humic clays some time after c. 7000 BP (c. 8000 to c. 7600 cal. yrs BP) in the lower tract of the Aire valley, near Goole, suggesting a change to lagoonal conditions. This was apparently caused by the ponding of freshwater against the rising estuary. It is also possible that drainage was impeded, associated with widespread deposition of organic sediment in the lower valley areas, which may have contributed to the creation of a lagoonal environment. The lagoon had silted up by c. 6000 BP (c. 7200 to c. 6600 cal. yrs BP), probably due to an increase in tidal asymmetry, and range, which resulted in a net surplus of sediment into the floodbasins and enabled the re-invasion of fen carr onto the site.The main period of organic sedimentation lasted for several millennia at each of the study sites, during which time Alnus glutinosa fen carr communities dominated the wet floodplain backswamp areas. During mid-Holocene times, the vegetation of the surrounding dryland, was colonised by a mixed woodland, with Tilia, Ulmus, Quercus, and probably, Corylus avellana and Fraxinus excelsior. Pinus sylvestris was also prevalent in the region.Alnus carr was progressively replaced by fen meadow communities, and then saltmarsh or freshwater reedswamp communities, due to a phase of positive sea-level tendency, which was recorded throughout the lower Aire valley between c. 4600 and c. 2700 BP (c. 5500 to c. 2700 cal. yrs BP). Remnants of a possible upper peat unit and diatom evidence from the upper clastic sediment is tentatively interpreted as indicating the contraction of estuarine conditions and a phase of negative sea-level tendency some time during the late-Iron Age.

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Medeiros, Elvio S. F. "Trophic ecology and energy sources for fish on the floodplain of a regulated dryland river Macintyre River, Australia /." Connect to this title online, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20051115.174552/.

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23

Kennedy, Thomas Brian. "Aquatic community organization in a diverse floodplain river fish fauna of the southeastern United States." Thesis, [Tuscaloosa, Ala. : University of Alabama Libraries], 2009. http://purl.lib.ua.edu/37.

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Medeiros, Elvio S. F., and n/a. "Trophic Ecology and Energy Sources for Fish on the Floodplain of a Regulated Dryland River: Macintyre River, Australia." Griffith University. Australian School of Environmental Studies, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20051115.174552.

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Drylands occupy about one-third of the world's land surface area and rivers in these regions have less predictable flow regimes than those in humid tropical and temperate regions. Australia's dryland river-floodplain systems cycle through recurrent periods of floods and droughts, oflen resulting in extreme hydrological variability. As a result, these systems have been described as having a 'boom and boost' ecology with periods of high productivity associated with flooding. Not surprisingly, flow and its variability have been recognised as major driving forces in the ecological functioning of Australian rivers and responses to flow variability from fish and aquatic invertebrates have been reasonably well described. Furthermore, the reduced amount of water reaching floodplain waterbodies due to river regulation has been held responsible for successional changes in aquatic biota and, consequently, the resources available for both fish and invertebrates. However, information regarding the impacts of water resource development has generally focused on within-channel processes of Australian rivers, not on floodplains, which are arguably more affected by water development. The following dissertation is concerned with how different types of natural and modified floodplain lagoons are able to trophically support their fish communities in the floodplain of the Macintyre River, Border Rivers catchment (QLD/NSW), a regulated dryland river. This study focuses on the influence of flooding and the implications of an extended dry period, and different levels of flow regulation, on the feeding ecology of selected fish species (Ambassis agassizil, Lelopotherapon unicolor and Nematalosa erebi) between 2001 and 2003. Food resources consumed by fish are hypothesised to vary in response to flooding, when inundation of isolated lagoons and vast floodplain areas can result in a burst of primary and secondary productivity. Given the permanently elevated water levels of some regulated floodplain lagoons, fish diets are hypothesised to be less variable in these floodplain habitats in comparison to diets of fish from floodplain lagoons with natural flow and water regime. Feeding ecology is examined firstly, in terms of diet composition of selected fish species, using stomach content analysis, and secondly, in relation to possible energy sources sustaining fish (using stable isotope analysis) in selected floodplain lagoons and a site in the main channel of the Macintyre River. The information produced should allow managers to take variations in food resources, food web structure and dietary ecology into account in management regimes for refugia and dryland systems in general. Factors such as diel and ontogenetic variations in dietary composition and food intake by fish are shown to considerably affect ovemll dietary patterns of each study species. Therefore, it is important to understand the contributions of such factors to the variability of fish dietary patterns before performing studies on resource use by fish in floodplain habitats of the Macintyre River. Major food categories consumed by the study species were zooplankton, aquatic invertebrates and detrital material. Zooplankton was of particular importance as this food item was ingested by all three study species at some stage of their life history. Spatial and temporal variation in diet composition of the study species was mostly associated with changes in prey items available across floodplain habitats and between seasons (summer/winter). The low magnitude of flooding events during the study period is arguably the most likely factor influencing the lack of patterns of variation in fish diets in floodplain habitats subject to flooding, whereas in non-flooded lagoons the observed dietary variation was a consequence of successional changes in composition of the aquatic fauna as the dry season progressed. Water regime had an important effect on differences in fish diet composition across lagoons, but further evaluation of the influence of flooding is needed due to overall lack of major flooding events during the study period. Autochthonous resources, namely plankton, were the basis of the food web and phytoplankton in the seston is the most likely ultimate energy source for fish consumers, via planktonic suspension feeders (zooplankton). Nevertheless, organic mailer could not be disregarded as an important energy source for invertebrates and higher consumers. In general, the present study does not provide support for the major models predicting the ftinctioning of large rivers, such as the River Continuum Concept and Flood Pulse Concept, which argue that allochthonous organic matter either from upstream or from the floodplain are the most important sources of carbon supporting higher consumers. In contrast, the Riverine Productivity Model would be more appropriate to describe the food web and energy sources for consumers in the Macintyre River floodplain as this model suggests that local productivity, based on autochthonous phytoplankton and organic matter, ftiels food webs in large rivers. The results of this study suggest that factors known to affect phytoplankton production in floodplain lagoons (e.g. flow regulation, turbidity and nutrient/herbicide inputs) must be seriously considered in current landscape and water management practices.

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Medeiros, Elvio S. F. "Trophic Ecology and Energy Sources for Fish on the Floodplain of a Regulated Dryland River: Macintyre River, Australia." Thesis, Griffith University, 2005. http://hdl.handle.net/10072/365765.

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Drylands occupy about one-third of the world's land surface area and rivers in these regions have less predictable flow regimes than those in humid tropical and temperate regions. Australia's dryland river-floodplain systems cycle through recurrent periods of floods and droughts, oflen resulting in extreme hydrological variability. As a result, these systems have been described as having a 'boom and boost' ecology with periods of high productivity associated with flooding. Not surprisingly, flow and its variability have been recognised as major driving forces in the ecological functioning of Australian rivers and responses to flow variability from fish and aquatic invertebrates have been reasonably well described. Furthermore, the reduced amount of water reaching floodplain waterbodies due to river regulation has been held responsible for successional changes in aquatic biota and, consequently, the resources available for both fish and invertebrates. However, information regarding the impacts of water resource development has generally focused on within-channel processes of Australian rivers, not on floodplains, which are arguably more affected by water development. The following dissertation is concerned with how different types of natural and modified floodplain lagoons are able to trophically support their fish communities in the floodplain of the Macintyre River, Border Rivers catchment (QLD/NSW), a regulated dryland river. This study focuses on the influence of flooding and the implications of an extended dry period, and different levels of flow regulation, on the feeding ecology of selected fish species (Ambassis agassizil, Lelopotherapon unicolor and Nematalosa erebi) between 2001 and 2003. Food resources consumed by fish are hypothesised to vary in response to flooding, when inundation of isolated lagoons and vast floodplain areas can result in a burst of primary and secondary productivity. Given the permanently elevated water levels of some regulated floodplain lagoons, fish diets are hypothesised to be less variable in these floodplain habitats in comparison to diets of fish from floodplain lagoons with natural flow and water regime. Feeding ecology is examined firstly, in terms of diet composition of selected fish species, using stomach content analysis, and secondly, in relation to possible energy sources sustaining fish (using stable isotope analysis) in selected floodplain lagoons and a site in the main channel of the Macintyre River. The information produced should allow managers to take variations in food resources, food web structure and dietary ecology into account in management regimes for refugia and dryland systems in general. Factors such as diel and ontogenetic variations in dietary composition and food intake by fish are shown to considerably affect ovemll dietary patterns of each study species. Therefore, it is important to understand the contributions of such factors to the variability of fish dietary patterns before performing studies on resource use by fish in floodplain habitats of the Macintyre River. Major food categories consumed by the study species were zooplankton, aquatic invertebrates and detrital material. Zooplankton was of particular importance as this food item was ingested by all three study species at some stage of their life history. Spatial and temporal variation in diet composition of the study species was mostly associated with changes in prey items available across floodplain habitats and between seasons (summer/winter). The low magnitude of flooding events during the study period is arguably the most likely factor influencing the lack of patterns of variation in fish diets in floodplain habitats subject to flooding, whereas in non-flooded lagoons the observed dietary variation was a consequence of successional changes in composition of the aquatic fauna as the dry season progressed. Water regime had an important effect on differences in fish diet composition across lagoons, but further evaluation of the influence of flooding is needed due to overall lack of major flooding events during the study period. Autochthonous resources, namely plankton, were the basis of the food web and phytoplankton in the seston is the most likely ultimate energy source for fish consumers, via planktonic suspension feeders (zooplankton). Nevertheless, organic mailer could not be disregarded as an important energy source for invertebrates and higher consumers. In general, the present study does not provide support for the major models predicting the ftinctioning of large rivers, such as the River Continuum Concept and Flood Pulse Concept, which argue that allochthonous organic matter either from upstream or from the floodplain are the most important sources of carbon supporting higher consumers. In contrast, the Riverine Productivity Model would be more appropriate to describe the food web and energy sources for consumers in the Macintyre River floodplain as this model suggests that local productivity, based on autochthonous phytoplankton and organic matter, ftiels food webs in large rivers. The results of this study suggest that factors known to affect phytoplankton production in floodplain lagoons (e.g. flow regulation, turbidity and nutrient/herbicide inputs) must be seriously considered in current landscape and water management practices.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Australian Environmental Studies
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26

Guimond, Julie K. "The effects of river connectivity on floodplain wetland ecology in Jasper National Park, Alberta, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60435.pdf.

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27

Sommer, Ted Robert. "The aquatic ecology of the Yolo Bypass floodplain : evaluation at the species and landscape scales /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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28

McManus, Erin Michael. "Primary succession of lianas in an Amazonian floodplain forest /." Electronic thesis, 2003. http://etd.wfu.edu/theses/available/etd-11292003-151813/.

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29

Clinton, Sandra Mae. "Microbial metabolism, enzyme activity and production in the hyporheic zone of a floodplain river /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/5560.

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Myers, David John. "OXYGEN AND HYDROGEN STABLE ISOTOPE RATIOS IN MISSISSIPPI RIVER FLOODPLAIN INVERTEBRATES: IMPLICATIONS FOR DISPERSAL AND FOOD WEB ANALYSIS." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/311.

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Understanding energy fluxes within and between floodplain water bodies, and between rivers and their floodplains is essential for comprehending the dynamics of modern, altered river systems. Floodplain aquatic invertebrates may move between habitats deliberately (through emergence and dispersal) or through passive transport during flooding. This movement may represent a significant flux of energy and an essential food web subsidy. I assessed the usefulness of the stable isotopes of hydrogen and oxygen (D and 18O respectively) for identifying the origins and movements of macroinvertebrates in Mississippi River floodplain water bodies. I sampled water and invertebrates from the Mississippi River, intermittent and permanent floodplain wetlands, and tributaries during 2007 and 2008. Results showed consistent relationships between δD and δ18O signatures in invertebrate tissues and their home water bodies. I also investigated whether δD and δ18O could be used as a multivariate "fingerprint" to trace a captured invertebrate back to its environment of origin. Results showed that δD can be a useful tracer of the movement of floodplain invertebrates in some cases, although δ18O is likely not suitable for that purpose.

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Olson, Patricia L. "Shallow subsurface flow systems in a montane terrace-floodplain landscape : Sauk River, North Cascades, Washington /." Thesis, Connect to this title online; UW restricted, 1995. http://hdl.handle.net/1773/5605.

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32

Ballinger, Andrea Alleyne. "Influence of habitat variability on macroinvertebrate biodiversity in river red gum Eucalyptus camaldulensis floodplain forest." Monash University, School of Biological Sciences, 2003. http://arrow.monash.edu.au/hdl/1959.1/5768.

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33

Olsen, Jesse Eric Burle. "Flood pulse influences on exploited fish populations of the Central Amazon." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/83864.

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Seasonally fluctuating water levels, known as flood pulses, influence the population dynamics and catches of fishes from river-floodplains. Although different measures of flood pulses, here called flood pulse variables, have been correlated to changes in catches of river-floodplain fishes, the flood pulse variables that have the strongest relationships to catches have not been identified. Furthermore, it is unclear if flood pulses influence catches of river-floodplain fishes with different life history strategies in different ways. Catches of 21 taxa from approximately 18,000 fishing trips were modeled as a function of fishing effort, gear type, seasonal flood pulse variables, and interannual flood pulse variables. These models were analyzed to understand which flood pulse variables had the strongest relationships to catches, and evaluate different flood pulse influences among taxa with different life history strategies. High water flood pulse variables generally had positive influences on catches in future years, while low water flood pulse variables generally had negative influences on catches in future years. Flood pulses generally had stronger influences on the catches of fishes with high fecundities and smaller eggs than on catches of fishes with low fecundities and larger eggs. Variation was observed in strengths and directions of flood pulse influences on catches of fishes with similar and different life history strategies. While my results were generally consistent with prevailing knowledge of how flood pulses influence catches of fishes, other biological factors of specific fish populations may further explain population responses to flood pulses.
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Furey, Maria A. "Perch availability and vegetation structure in upland breeding habitat selection by reg-winged blackbirds in a floodplain restoration site /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418020.

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35

Parsons, Helena. "An analysis of landscape diversity on the floodplain of a Scottish wandering gravel-bed river." Thesis, University of Stirling, 2000. http://hdl.handle.net/1893/1222.

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This thesis examines landscape diversity within alluvial valley floors using the case study of a Scottish wandering gravel-bed river. The thesis aims are two-fold; firstly to investigate the spatial and temporal patterns of valley floor landscape diversity within semi-natural environments, and secondly to develop a methodology for quantifying alluvial valley floor landscape diversity in space and time. The diversity analysis involves quantifying the spatial patterns of geo-, pedo- and biodiversity (flora) within floodplain zones which have been exposed to approximately 100 years of recovery since flood embankment abandonment along the most active reaches of the river. In addition historical records including aerial photographs, maps and narrative accounts were used to assess the temporal patterns of the diversity of landscape patches and how they have changed through time using a series of landscape indices. The analysis thus accounts for the role of river channel change in producing a complex mosaic of land cover types within alluvial valley floors. The spatial analysis revealed that landscape diversity tends to be greater in the perpendicular orientation to the main channel, i.e. along an aquatic-to-terrestrial environmental gradient. The temporal analysis results revealed that the landscape over the last 50 years has changed from being dominated by few relatively large isodiametric patches to a landscape dominated by small irregular shaped patches. Thus although landscape patch richness has increased along with an increase in land cover types through time, the landscape patches have also become more fragmented. The major outcomes of the research are the deriving of quantitative results of the spatial and temporal patterns of floodplain landscape diversity, an evaluation of the role of channel dynamics in creating the diverse mosaic of land cover types, the identification of the environmental controls and supporting floodplain habitats of a number of rare species and a proposed methodology for assessing landscape diversity to be validated on other river systems.

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Piotrowski, Jeffrey Scott. "Succession of arbuscular mycorrhizal fungi causes, consequences, and considerations /." CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05272008-134138/.

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37

Allen, Bruce Peter. "Vegetation dynamics and response to disturbance, in floodplain forest ecosystems with a focus on lianas." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1179427491.

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Anderson, Robert Gray. "BREEDING PRODUCTIVITY, NEST DISTRIBUTION, AND POPULATION ECOLOGY OF WOOD DUCKS IN FLOODPLAIN AND UPLAND FORESTS OF SOUTHERN ILLINOIS." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/154.

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Wood ducks are thought to depend on mature hardwood forests juxtaposed with palustrine wetlands but these habitats have been continuously degraded or destroyed since European settlement. Wood ducks are adaptable and the use of marginal habitats and nest boxes has extended their range and probably was important to the recovery of wood duck populations. Until now no study has analyzed the contribution of upland nesting to local population growth and maintenance. I investigated predation effects on nest site selection using wood duck nests and simulated nests placed in natural cavities. Using demographic data collected on wood ducks in southern Illinois, I created a population model to compare growth rates of population segments that nested in upland and floodplain habitats. During 1993-1998, 179 of 244 radiomarked hens remained on the study area as resident hens. One hundred-four nests were located by following radiomarked hens and 66% of nests were found in upland forests. Nests in the floodplain were initiated earlier than nests in the upland. Thirty-six percent of known nest cavities were used in subsequent years but <10% were used by the same hen. Nest success was greater in upland habitats (0.78 ± 0.10) than in floodplain habitats (0.54 ± 0.18). Hen survival through the nesting season was 0.80 ± 0.03 and did not differ between habitats or age classes. Sixty-five percent (n = 43) of simulated floodplain nests were destroyed compared to 33% (n = 45) in the upland. Logistic regression models of simulated nest data indicated cavity security could be important in the fragmented floodplain forests of Union County Conservation Area (UCCA). No physical characteristics of wood duck nest cavities differentiated successful and unsuccessful nesting attempts. The growth rate of the local population was positive and estimated to be about 3%. Lambda was most sensitive to upland nesting parameters and floodplain parameters appeared to have little impact on lambda. Hens nesting in the area appear to have adapted to predation pressure by nesting in more secure floodplain cavities at UCCA or by nesting in the upland habitats. Floodplain and upland habitats are ecologically intertwined and the local wood duck population would not survive if either habitat were destroyed or severely degraded.

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Collings, Sandy Lyn. "Economic consequences of ecological change: restoration options for the Mfolozi floodplain and implications for Lake St. Lucia, South Africa." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1006950.

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Lake St Lucia in northern KwaZulu-Natal, South Africa, experiences severe ecological stress during dry periods largely as a result of diminishing freshwater supplies and conditions of hypersalinity. Possible intervention involves diverting the Mfolozi River to the St Lucia Lake system. However, due to high sediment loading, water from the Mfolozi river requires considerable filtration before a link can be established. A suggested option considered in this study is to restore the existing sugarcane farmlands on the Mfolozi Floodplain (~20 800 ha) to previous wetland conditions to reinstate a sediment removal function amongst other benefits. Proposed restoration will have a direct impact on the industries currently supported by the iSimangaliso Wetland Park and the Mfolozi Floodplain (tourism, sugar, conservation). to understand a measure of such impacts, ecosystem services for both Lake St Lucia and the Mfolozi Floodplain were analysed (flood alleviation, water provision, water purification, sediment regulation, tourism, fisheries, vegetation for harvest, existence, cultural and research). Annual economic values for each ecosystem service were determined by means of valuation methods that included benefit transfer and replacement cost. Results showed a current annual minimum value of the Mfolozi Floodplain and Lake St Lucia as greater than R21 million and R1.1 billion respectively. Partial restoration of the floodplain (~6 000 ha) is expected to increase the sum of all ecosystem services values by approximately 26% for the Mfolozi Floodplain and by 23% for the St Lucia System. Full restoration (~20 800 ha) increases the total ecosystem services value by 88% and 50% for the Mfolozi Floodplain and St Lucia System respectively. Results showed that economic values for existence, fisheries, tourism and water provision increase by the greatest percentage for the St Lucia System under both restoration scenarios. Partial and full restoration of the floodplain will result in the greatest increases in economic value for the services existence, tourism, fisheries and the harvesting of vegetation on the Mfolozi Floodplain.

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McGinness, Heather M., and n/a. "SPATIAL HETEROGENEITY AND HYDROLOGICAL CONNECTIVITY IN A DRYLAND, ANABRANCHING FLOODPLAIN RIVER SYSTEM." University of Canberra. Resource, Environmental & Heritage Sciences, 2007. http://erl.canberra.edu.au./public/adt-AUC20070731.094606.

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Riverine landscapes are complex. More than just a single channel, they comprise a shifting mosaic of hydrogeomorphic patches with varying physical and biological characteristics. These patches are connected by water during flows of varying magnitude and frequency, at a range of spatial and temporal scales. Combined, landscape complexity and hydrological connectivity create biological diversity that in turn maintains the productivity, ecological function, and resilience of these systems. This thesis investigates the ecological importance of spatial heterogeneity and temporal hydrological connectivity in a dryland floodplain river landscape. It focuses on anabranch channels, and uses major carbon sources in these and adjacent landscape patches as indicators of ecological pattern and process. A conceptual model was proposed, describing the potential effects upon the distribution and availability of major carbon sources of: a) a spatial mosaic of hydrogeomorphic patches in the landscape (e.g. anabranches, river channel, and wider floodplain); and b) four primary temporal phases of hydrological connection during flow pulses (disconnection, partial connection, complete connection, and draining). This was then tested by data collected over a three year period from a 16 km reach of the lower Macintyre River (NSW/QLD Australia). Results were examined at multiple spatial scales (patch scale � river channel vs. anabranches vs. floodplain; between individual anabranches; and within anabranches � entry, middle and exit sites). The data indicate that spatial heterogeneity in the lower Macintyre River landscape significantly influences ecological pattern. Carbon quantity was greater in anabranch channels compared to adjacent river channel patches, but not compared to the floodplain; while carbon quality was greater in anabranch channels compared to both adjacent river channel and floodplain patches. Stable isotope analysis indicated that carbon sources that were predominantly found in anabranch channels supported both anabranch and river organisms during a winter disconnection phase. Other carbon sources found in the main river channel and the wider floodplain appeared to play a comparatively minimal role in the food web. Different phases of hydrological connection between anabranch channels and the main river channel were associated with differences in the availability of carbon sources. In the river channel, draining of water from anabranches (the draining phase) was associated with relatively high concentrations of dissolved organic carbon (DOC) and low concentrations of phytoplankton. Conversely, the disconnection phase was associated with relatively low concentrations of DOC and high concentrations of phytoplankton in the river channel. In anabranch channels and their waterbodies, the disconnection and draining phases were associated with high concentrations of both DOC and phytoplankton. Concentrations of these carbon sources were lowest in anabranches during the partial and complete connection phases. Different hydrological connection phases were also associated with changes in trophic status in the aquatic components of the landscape. On the riverbanks, relatively low rates of benthic production and respiration during the complete connection phase were associated with heterotrophy. The remaining phases appeared to be autotrophic. Benthic production on riverbanks was greatest during the disconnection phase, and respiration was greatest during the partial connection phase. In the anabranch channels, rates of production and respiration were similar during the disconnection phase, and were associated with heterotrophy in the anabranch waterbodies. The remaining phases appeared to be autotrophic. Respiration was greatest in anabranches during the disconnection phase, and production was greatest during the draining phase. Both production and respiration were lowest during complete connection. These differences and changes varied according to the landscape patch examined. At a landscape scale, anabranch channels act as both sinks and suppliers of carbon. High rates of sediment deposition facilitate their role as sinks for sediment-associated carbon and other particulate, refractory carbon sources. Simultaneously, anabranch channels supply aquatic carbon sources from their waterbodies, as well as via processes such as inundation-stimulated release of DOC from surface sediments. Modelled data indicated that water resource development reduces the frequency and duration of connection between anabranch channels and the main river channel. This loss of landscape complexity via loss of connectivity with anabranches has the potential to reduce the total availability of carbon sources to the ecosystem, as demonstrated by a modelled 13% reduction in potential dissolved organic carbon release from anabranch sediments. This thesis has demonstrated the importance of spatial heterogeneity in riverine landscapes, by documenting its association with variability in the distribution and quality of primary energy sources for the ecosystem. It has shown that this variability is augmented by different phases of hydrological connectivity over time. Spatial heterogeneity and hydrological connectivity interact to increase the diversity and availability of ecological energy sources across the riverine landscape, at multiple spatial and temporal scales. This has positive implications for the resilience and sustainability of the system. Anabranch channels are particularly important facilitators of these effects in this dryland floodplain river system. Anabranch channels are �intermediate� in terms of spatial placement, temporal hydrological connection, and availability of carbon sources; of high value in terms of high-quality carbon sources; and relatively easy to target for management because of their defined commence-to-flow levels. Further research should be directed toward evaluating other ecological roles of anabranch channels in dryland rivers, thereby providing a more complete understanding of the importance of connectivity between these features and other patches. This knowledge would assist management of floodplain river landscapes at larger regional scales, including amelioration of the effects of water resource development.

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41

Horton, Kimberly. "Roadway effects on the hydrologic regime of temporary wetlands in the Missouri River floodplain in Missouri." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4241.

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Thesis (M.S.)--University of Missouri-Columbia, 2005.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 11, 2007) Includes bibliographical references.

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42

Tal, Ophir. "Comparative flowering ecology of Fraxinus excelsior, Acer platanoides, Acer pseudoplatanus and Tilia cordata in the canopy of Leipzig's floodplain forest." Doctoral thesis, Universitätsbibliothek Leipzig, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:15-20080603-064807-8.

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How do gender separation and the transition to wind pollination happen in temperate trees? What does the reproductive ecology in the crowns of temperate forest trees look like? These connected questions intrigued researchers before and since Darwin but it is only in the last years that a direct study of the latter question has been enabled. A research crane was used to study the flowering ecology of Fraxinus excelsior, Acer platanoides, Acer pseudoplatanus and Tilia cordata in Leipzig’s floodplain forest. These species originate from hermaphrodite insect pollinated plant families and exhibit different grades of gender separation and different stages between insect and wind pollination. As they are typical elements of temperate deciduous forests, an ecological comparison of their flowering ecology may shed new light on the evolution of gender separation and wind pollination in this habitat. Using the crane, gender distribution, flowering phenology in relation to microclimate, pollination levels (including pollen tubes in the styles) and fruit set were studied in ca. 200 trees over 2-4 years. Main results are a new appreciation of the sexual system of Fraxinus excelsior as dioecy, of Tilia cordata as andromonoecy and a detailed description of the intricacies of the heterodichogamous sexual system of Acer pseudoplatanus. Several flowering phenological patterns are described in Fraxinus excelsior and Acer platanoides in relation to microclimate in early spring. The role of small arthropods is underlined as gall mites may play a role in gender specialisation in Fraxinus excelsior, gall midges are related to maleness in T. cordata and thrips are probably the pollinators of Acer pseudoplatanus in the stand. Thrips pollination is suggested to be a possible stepping-stone between insect pollination and wind pollination, which may drive the transition in Acer pseudoplatanus and possibly in intensively flowering dominant species in other habitats. The study presents the complexity of the reproductive systems and the strong interdependencies among their elements.

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43

Weeks, Katherine Farrah. "Population ecology of the floodplain herb Macbridea caroliniana (Lamiaceae) with investigations on the species' habitat, breeding system and genetic diversity." Connect to this title online, 2009.

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44

Michel, James T. Helfield James M. "Seed rain and selected species germination and growth trials : implications for natural and augmented revegetation of post-dam Elwha River floodplain and reservoir sediments /." Online version, 2010. http://content.wwu.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=361&CISOBOX=1&REC=5.

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45

Allen, Bruce Peter. "Vegetation dynamics and response to disturbance of floodplain forest ecosystems with a focus on lianas." The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1179427491.

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46

King, Jessica. "The succession of a contaminated floodplain: reclaiming the West Bottoms." Kansas State University, 2013. http://hdl.handle.net/2097/15683.

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Master of Landscape Architecture or Regional and Community Planning
Department of Landscape Architecture/Regional and Community Planning
Timothy Keane
Kansas City is expecting a 25% growth in population by 2050. This design proposal promotes West Bottoms as a potential area to house some of the new population, and more importantly supply a live and work community for these people. West Bottoms is also home to major industry in Kansas City as well as an up and coming art culture. West Bottoms has great potential for a community that allows the existing and new population to be a part of a live-work-play community with the vacancies in the area. The projected population growth is expected to promote sprawl, further increasing the average driving time to the city. West Bottoms currently has few connections to the downtown and offers few reasons to come to the area. These connections are mainly major bridges or highways. Another issue West Bottoms faces is flooding problems from OK Creek and Turkey Creek, which lead into the Kansas and Missouri Rivers. Finally, post and present industrial soil contamination threatens the groundwater. When mixed with flooding concerns, this contamination is potentially harmful for the health of downstream cities. Drawing inspiration from travels, Kansas City charm, plants, art, and water storage, case studies were researched. Themes from each case study were quantified. These themes paired with inventory and analysis of the West Bottoms provided the basis for the design proposed here. The successional design of the area will progress from a contaminated landscape to a landscape that holds floodwater. The final design holds all of the stormwater from the 100 year 1, 2, 3, 6, 12, and 24 hour rain events. The final design incorporates areas of learning, a variety of paths and seating, a live-work-play community, clean and creative industry, and an art culture that sustains the excitement for the timeline of succession. Overtime this landscape will evolve into a new destination for Kansas City using an integrated solution remediating the soil and holding flood waters as an amenity for the new population.

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47

Diefenderfer, Heida Lin. "Channel morphology and restoration of Sitka spruce (Picea stichensis) tidal forested wetlands, Columbia River, U.S.A. /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/5565.

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48

Wellman, David I. "Post-flood recovery and distributions of fishes in the New River Gorge National River, West Virginia." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3455.

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Thesis (M.S.)--West Virginia University, 2004.
Title from document title page. Document formatted into pages; contains xii, 169 p. : ill., maps. Vita. Includes abstract. Includes bibliographical references.

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49

Keruzoré, Antoine. "Aquatic vegetation processes in a floodplain-river system and the influence of lateral dynamics and connectivity." Thesis, University of Stirling, 2012. http://hdl.handle.net/1893/7677.

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In river ecology the description and understanding of near-natural ecosystem functionality is a difficult task to achieve as the majority of river floodplains have been intensively impacted by human activities. This work addresses ecological functionality of a relatively unimpacted large river system, focussing on the lateral dynamic and connectivity mechanisms driving aquatic vegetation processes. Macrophytes were found to be very patchily distributed at the riverscape scale, being mainly confined to low energy lateral habitats in the floodplain, such as backwaters. Backwaters provided favourable conditions for plants to colonise and recruit and contributed highly to species diversity and productivity at the floodplain scale. Differences between backwaters were attributed to the frequency of connectivity with the main channel during flood events. Nevertheless, the ecological mechanism driving diversity through flooding appears not to be related to flow disturbance. Biomass produced in backwaters was found to remain stable after potentially scouring floods. Therefore the hypothesis that flood disturbances promote species diversity through the removal and destruction of biomass and rejuvenate communities such that species coexistence is increased was rejected. Rather, it appears that diversity in backwaters increases along a temporal gradient as a response to the input of colonists and their accumulation overtime through successive flood inputs. Despite the apparently non-destructive effect of floods on macrophyte biomass, backwaters appear to have a significant role in exporting large amounts of plant propagules from the site of production. Backwaters represented a net source of propagules which highly enriched the main channel pool of potential colonists. However, whereas propagules could be dispersed for long distances in flood flows the probability for them to reach a suitable downstream habitat was extremely low. This work showed that dispersal at baseflow and entry to backwaters through the downstream end after short dispersal drift provided a greater chance of successful colonisation despite the individually much shorter distance moved. Backwaters were demonstrated to be rather isolated aquatic habitats, even though they experience hydrological connectivity, suggesting that primary colonisation of these sites is a limiting step. Instead, colonisation was shown to rely primarily on propagules generated internally by established plants. Whereas colonisation could occur via internal re-organisation of existing plant propagules, the backwater seed bank could also contribute to the macrophytes species established in backwaters. Such contribution was consistently low to medium along a gradient of disturbances and connectivity and showed independence from such river flow processes. Species richness was found to be higher in the established species than in the seed bank, suggesting that asexual reproduction is prioritised by aquatic vegetation in riverine backwaters. The occurrence or persistence of macrophyte species in backwaters depends upon rhizome and plant shoot regeneration. The lack of influence of connectivity revealed that plants may originate from both in situ and externally waterborne vegetative propagules derived from other upstream backwaters. This research demonstrated that the lateral dynamic and associated connectivity are major components of river floodplain ecology which generate a wide spectrum of habitats and have a controlling effect on vegetation processes. Therefore a naturally dynamic ecological state is required to support ecosystem functionality in large river floodplains and especially to maintain a high level of species diversity, productivity and colonisation of backwaters by macrophytes.

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Treviño, Jessica Marie. "Effects of Macrophyte Functional Diversity on Taxonomic and Functional Diversity and Stability of Tropical Floodplain Fish Assemblages." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804900/.

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Multiple dimensions of biodiversity within and across producer and consumer guilds in the food web affect an ecosystem’s functionality and stability. Tropical and subtropical aquatic ecosystems, which are extremely diverse, have received much less attention than terrestrial ecosystems in regards to the effects of biodiversity on ecosystem functioning. We conducted a field experiment that tested for effects of macrophyte functional diversity on diversity and stability of associated fish assemblages in floodplain lakes of the Upper Paraná River floodplain, Brazil. Three levels of macrophyte functional diversity were maintained through time in five floodplain lakes and response variables included various components of fish taxonomic and functional diversity and stability. Components of functional diversity of fish assemblages were quantified using a suite of ecomorphological traits that relate to foraging and habitat use. Response variables primarily distinguished macrophyte treatments from the control. Macrophyte treatments had, on average, double the number of species and total abundance than the control treatment, but only limited effects on stability. The high diversity treatment was essentially nested within the low diversity for assemblage structure and had similar or even slightly lower levels of species richness and abundance in most cases. Gymnotiformes and young-of-year were diverse and relatively abundant in macrophyte treatments contributing to the large differences in diversity between macrophyte and control treatments. Higher fish diversity in structured habitats compared to more homogenous habitats is likely associated with increased ecomorphological diversity to exploit heterogeneous microhabitats and resources provided by the macrophytes.

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Dissertations / Theses on the topic 'Floodplain ecology'

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