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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Created stormwater wetlands as wetland compensation and a floristic quality approach to wetland condition assessment in central Alberta

Forrest, Andrew SM 11 1900 (has links)
In Alberta, almost all created wetlands accepted as compensation have been naturalized stormwater management facilities. Our investigation of 32 created and natural wetlands in central Alberta determined that created wetlands have steeper shoreline slopes, largely as a result of their primary function as stormwater retention ponds. This resulted in distinctly different vegetation zonation, with the steeper slopes of created wetlands resulting in fewer, narrower wetland vegetation zones. This was reflected in reduced species richness and abundance of wetland songbirds at created wetlands. This study also discusses the development of a Floristic Quality Assessment (FQA) approach, a standardized, quantitative approach to measuring wetland condition, for Albertas Parkland and Boreal natural regions. I present plant survey data from the 32 wetlands as validation of the effectiveness of this approach. This study provides information on current wetland compensation practices and a potential wetland assessment tool; both topics that are directly relevant to the implementation of wetland compensation policies in Alberta. / Ecology
72

Experimental manipulation of temporary wetlands for the restoration of wildlife habitat in the Watervalley Wetlands, Upper South East of South Australia /

Birrell, Michaela Anne Unknown Date (has links)
More than 90% of wetlands in the Upper South East of South Australia have been lost, primarily through drainage and clearing vegetation for agriculture. Over the last 20 years, temporary, semi-permanent and permanent wetlands have been, and continue to be, hydrologically restored to enhance and maintain biodiversity. / In this study, habitat in four seasonal temporary wetlands in the Watervalley Wetlands complex, in the Upper South East, was manipulated to determine the potential for natural regeneration and human-induced restoration techniques. The seed banks of three wetlands were studied using the seedling emergence technique and I compared the composition of seed banks and the history of disturbance in these wetlands. The seed bank in the Parkhill wetland contains introduced amphibious and terrestrial plants as well as a suite of native species. Experiments using soil from the Parkhill wetland revealed that the dominant species found in the threatened vegetation association, Selliera radicans herbland, could be restored by transferring soil. The seed bank in Mrs White Lagoon lacks amphibious and terrestrial species. The seed bank in Jaffrays Lagoon is in good condition with an absence of introduced species and a suite of amphibious, submerged, emergent and terrestrial species. Therefore, Jaffrays Lagoon was identified as a donor wetland, from which soil could be transferred to nearby wetlands that have been hydrologically restored, to introduce a suite of plant species and accelerate succession in plant communities. / Soil was transferred from Jaffrays Lagoon to three plots in Mrs White Lagoon to determine the potential for accelerating succession. Biomass of submerged species increased significantly in the first growing season, during a submerged water regime. Further studies are recommended to trial this technique in waterlogged conditions with the aim of triggering the germination of emergent and amphibious species. / In a controlled experiment, in the Mandina Marshes, sedges were subjected to rotary-hoeing, slashing and slashing and removing the clippings to create a mosaic of open water and vegetation. Such a mosaic may enhance waterfowl habitat. The responses of aquatic invertebrates, specifically early colonisers, to the vegetation treatments were measured to determine the potential effects on the invertebrate components of waterfowl diets. Results indicate that rotary-hoeing sedges in the Madina Marshes may increase diversity and evenness of early colonisers without reducing the total abundance of aquatic invertebrates. By contrast, slashing and slashing and removing the clippings appears to reduce both diversity and abundance of early colonisers. / An exclosure was constructed in a section of riparian and littoral habitat in the Parkhill wetland to test the response of plant communities to the cessation of grazing by sheep and cattle. In the first 12 months, Melaleuca species returned, species richness and diversity indices decreased and the biomass of vegetation increased in the littoral zone but not in the riparian zone. Variables other than the cessation of grazing probably contributed to these results and recommendations are made for the first 10 years of a monitoring program. / Recommendations for future wetland restoration and ongoing management of the Watervalley Wetlands are provided, based on the outcomes of these experiments. / Thesis (MApSc(EnvironmentRecreationMg))--University of South Australia, 2003.
73

Experimental manipulation of temporary wetlands for the restoration of wildlife habitat in the Watervalley Wetlands, Upper South East of South Australia /

Birrell, Michaela Anne Unknown Date (has links)
More than 90% of wetlands in the Upper South East of South Australia have been lost, primarily through drainage and clearing vegetation for agriculture. Over the last 20 years, temporary, semi-permanent and permanent wetlands have been, and continue to be, hydrologically restored to enhance and maintain biodiversity. / In this study, habitat in four seasonal temporary wetlands in the Watervalley Wetlands complex, in the Upper South East, was manipulated to determine the potential for natural regeneration and human-induced restoration techniques. The seed banks of three wetlands were studied using the seedling emergence technique and I compared the composition of seed banks and the history of disturbance in these wetlands. The seed bank in the Parkhill wetland contains introduced amphibious and terrestrial plants as well as a suite of native species. Experiments using soil from the Parkhill wetland revealed that the dominant species found in the threatened vegetation association, Selliera radicans herbland, could be restored by transferring soil. The seed bank in Mrs White Lagoon lacks amphibious and terrestrial species. The seed bank in Jaffrays Lagoon is in good condition with an absence of introduced species and a suite of amphibious, submerged, emergent and terrestrial species. Therefore, Jaffrays Lagoon was identified as a donor wetland, from which soil could be transferred to nearby wetlands that have been hydrologically restored, to introduce a suite of plant species and accelerate succession in plant communities. / Soil was transferred from Jaffrays Lagoon to three plots in Mrs White Lagoon to determine the potential for accelerating succession. Biomass of submerged species increased significantly in the first growing season, during a submerged water regime. Further studies are recommended to trial this technique in waterlogged conditions with the aim of triggering the germination of emergent and amphibious species. / In a controlled experiment, in the Mandina Marshes, sedges were subjected to rotary-hoeing, slashing and slashing and removing the clippings to create a mosaic of open water and vegetation. Such a mosaic may enhance waterfowl habitat. The responses of aquatic invertebrates, specifically early colonisers, to the vegetation treatments were measured to determine the potential effects on the invertebrate components of waterfowl diets. Results indicate that rotary-hoeing sedges in the Madina Marshes may increase diversity and evenness of early colonisers without reducing the total abundance of aquatic invertebrates. By contrast, slashing and slashing and removing the clippings appears to reduce both diversity and abundance of early colonisers. / An exclosure was constructed in a section of riparian and littoral habitat in the Parkhill wetland to test the response of plant communities to the cessation of grazing by sheep and cattle. In the first 12 months, Melaleuca species returned, species richness and diversity indices decreased and the biomass of vegetation increased in the littoral zone but not in the riparian zone. Variables other than the cessation of grazing probably contributed to these results and recommendations are made for the first 10 years of a monitoring program. / Recommendations for future wetland restoration and ongoing management of the Watervalley Wetlands are provided, based on the outcomes of these experiments. / Thesis (MApSc(EnvironmentRecreationMg))--University of South Australia, 2003.
74

Micronutrient and heavy metal concentrations observed in natural wetland macrophytes in Arizona

Rohovit, Laska. January 1999 (has links) (PDF)
Thesis (M.S. - Soil, Water and Environmental Science)--University of Arizona. / Includes bibliographical references (leaves 107-111).
75

Establishment vegetation patterns in an artificial urban wetland as a basis for management /

Conran, Leigh Garde. January 1991 (has links) (PDF)
Thesis (M. Env. St.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1993. / Includes bibliographical references (leaves [34-40]).
76

Transitions between ecological regimes in salinising wetlands /

Sim, Lien Louise. January 2005 (has links)
Thesis (Ph.D.)--Murdoch University, 2005. / Thesis submitted to the Division of Science and Engineering. Bibliography: leaves 267-287.
77

The restoration of wetland functions at the Rio Bosque Wetlands Park in El Paso, Texas, USA

Sherrill, Ursula Rose. January 2007 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
78

The floral and faunal recovery of a restored coastal wetland : Kunz Marsh, South Slough, Coos Bay, Or. /

Fritz, Gisela B. January 2001 (has links)
Thesis (M.A.)--Humboldt State University, 2001. / Includes bibliographical references (leaves 98-102). Also available online.
79

Effects of timing and duration of flooding on phosphorus release in four restored wetlands around Agency and Upper Klamath Lakes, Oregon /

Stevens, Carla J. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 40-48). Also available on the World Wide Web.
80

Geotechnical investigation of Montrose wetland site

Ryan, Christopher R., January 2004 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xii, 191 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references (p. 117-119).

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