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Trophic ecology and energy sources for fish on the floodplain of a regulated dryland river Macintyre River, Australia /Medeiros, Elvio S. F. January 2004 (has links)
Thesis (Ph. D.)--Griffith University, 2004. / Title from PDF title page (viewed on Dec. 10, 2006). Includes bibliographical references (p. 226-247).
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Spatio-temporal modeling of seed dispersal and aquatic plant community restoration in the Kissimmee River floodplainUnknown Date (has links)
This study created an ecological spatial model, using a geographic information system, to visualize the influence of hydrochory on restoration of the three dominant wetland communities of broadleaf marsh, wetland shrub, and wet prairie across the floodplain of the Kissimmee River. Primary parameters incorporated into the model included floodplain hydrology, seed characteristics of buoyancy and dispersal rates, and species flood tolerance. S²rensen's similarity index, comparing spatial agreement among model output and observed community data, resulted in values of BLM-BB = 0.10, BLM = 0.07, WS = 0.21, and WP = 0.36. The significant discrepancies between modeled and observed community spatial coverage indicated a need for incorporation of more stochastic variables of climatic disturbances, nutrient availability, and soil characteristics. More research on species flood tolerance across smaller spatial scales is also needed, and base data incorporated into the model should also be reliable and consistent if accuracy is to be achieved. / by Stevee Kennard. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Influence of habitat variability on macroinvertebrate biodiversity in river red gum Eucalyptus camaldulensis floodplain forestBallinger, Andrea Alleyne January 2003 (has links)
Abstract not available
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Geomorphic form and process of sediment flux within an active orogen : denudation of the Bolivian Andes and sediment conveyance across the Beni Foreland /Aalto, Rolf Erhart. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Includes bibliographical references (leaves 240-251).
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OXYGEN AND HYDROGEN STABLE ISOTOPE RATIOS IN MISSISSIPPI RIVER FLOODPLAIN INVERTEBRATES: IMPLICATIONS FOR DISPERSAL AND FOOD WEB ANALYSISMyers, David John 01 December 2010 (has links)
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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Fish assemblage organization in the Amazon River floodplain : species richness, spatial distribution and recruitment processesPetry, Paulo 25 May 2000 (has links)
The composition and distribution of fish assemblages was examined in a
floodplain lake system in the Amazon basin. Quantitative samples were
collected during the 1992-1993 flooding season at Marchantaria Island, Solimoes
River. A total of 25,819 specimens representing 8 orders, 30 families, 101
genera and 139 species of fish were collected. Analysis of species richness
distribution among 7 vegetation strata showed that vegetated sites had higher
species richness than unvegetated sites. Stands of Paspalum repens had the
most diverse fish fauna. Canonical correspondence analysis (CCA) was used to
investigate relationship between fish assemblages and 16 environmental
variables. CCA revealed that dissolved oxygen, water transparency, water depth
and aquatic vegetation structure were significantly related to fish assemblage
organization. The results suggest that physiological adaptations to hypoxia and
habitat complexity play a major role in the organization of these assemblages.
The morphology, ontogenetic development, shape variability and deposition of
otolith microincrements are described for floodplain serrasalmin fishes.
Serrasalmin otoliths were similar to other ostariophysan, nevertheless their
shape was species-specific. Elliptical Fourier analysis showed that Mylossoma
aureum lapilli were highly variable in shape when compared to closely related
species. PCA and discriminant function analysis indicated that two distinct forms
of lapillus can be recognized for M. aureum, and intra-species variation was
higher than inter-species variation. Otolith microincrement analysis was tested
for these fishes, and microincrement deposition validation showed that Piaractus
brachipomus deposits otolith increments on a daily basis. Patterns of spatial
distribution, growth and mortality characteristics of larvae and juvenile were
examined for M. aureum inhabiting the Marchantaria Island floodplain. Otolith-derived
birth date reconstruction showed that M. aureum spawning season
extended from late November to March, and peak larvae recruitment to the island
occurred in mid-December. Larvae and juveniles had different spatial
distributions in relation to habitat usage. Instantaneous growth coefficients (g)
varied from 0.0197(d�����) to 0.265(d�����) among cohorts. Early-season cohorts had
wider otolith microincrements and higher instantaneous growth coefficients than
late-season cohorts. Mortality estimated by the decline of loge (abundance)
regressed on age indicated that cohort-specific instantaneous mortality varied
significantly among cohorts, ranging from 0.027(d�����) (2.6%/d) to 0.103(d�����)
(9.7%/d). / Graduation date: 2001
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Perceptions of the impacts of artificial flood releases on the general use of the natural resources of the Pongolo River floodplain, South Africa.Salagae, Modukanele Alloycius. January 2007 (has links)
A social survey of the communities living adjacent to the Pongolo river floodplain was carried out, in order to understand the perceptions of the impact of artificial flood releases on the general use of natural resources of Pongolo floodplain in terms of: general resource use, stream flow, water quality and subsistence agriculture. The results show that floodplain communities perceive that the present artificial flood releases which are intended to maintain the environmental requirements of the floodplain are not meeting their needs nor the needs of the environment. Key perceptions on environmental impacts identified are: (i) reduction in water required to maintain floodplain resources, (ii) deterioration in water quality and (iii) decrease in available floodplain land and natural resources. / Thesis (M.Env.Dev.) - University of KwaZulu-Natal, Pietermaritzburg, 2007.
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Long-term Responses of Phalaris arundinacea and Columbia River Bottomland Vegetation to Managed FloodingFarrelly, Tina Schantz 01 January 2012 (has links)
I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. Altered hydrology has reduced historically high spring flow and prematurely initiated the historic summer drying period at SBW. This alteration has increased the coverage of invasive plants (e.g., P. arundinacea) causing a decrease in native plant cover and thus degrading ecological functions. SBW managers installed a water control structure (WCS) between SBW and the Columbia Slough/River system to impound winter rainfall and thus approximate the ecological benefits that natural flooding provided as well as reduce the abundance of P. arundinacea. Prior researchers conducted intensive vegetation and hydrological monitoring in 2003 (during the season immediately before WCS installation) and 2004. I conducted similar analysis in the fifth and sixth years, 2008 and 2009, following establishment of the WCS. Both study years, I determined percent cover of all vegetation on transects established in 2003. The results, including 2004, as well as 2008 and 2009 showed a reduced cover of P. arundinacea in areas experiencing at least 0.6 meters of inundation and an increased cover of native plant communities when compared to the 2003 baseline data. Native Carex aperta Boott. cover increased 7-fold from 0.3% to 2.3%; Polygonum species cover increased from 20.0% to 52.6%; and Salix lucida Muhl. ssp. lasiandra (Benth.) E. Murray cover increased from 10.9% to 15.5% cover. P. arundinacea declined by over one-third from 44.4% to 28.1% cover following water management. Since hydrology management began, the native Polygonum species community replaced P. arundinacea as the dominant species in the emergent zone. The results of this study refined the suggested depth of inundation needed to reduce P. arundinacea cover in such lake-wetland complexes as SBW from 0.85 meters (based on 2004 study results) to 0.6 meters. Shannon Diversity decreased following water management. The findings of this study demonstrated that water management can enhance native bottomland communities, especially those comprised of obligate wetland species, and reduce P. arundinacea cover in areas experiencing at least 0.6 meters of inundation.
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Effects of Macrophyte Functional Diversity on Taxonomic and Functional Diversity and Stability of Tropical Floodplain Fish AssemblagesTreviño, Jessica Marie 08 1900 (has links)
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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Recruitment ecology of fish in floodplain rivers of the southern Murray-Darling Basin, AustraliaKing, Alison Jane, 1974- January 2002 (has links)
Abstract not available
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