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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.
81

Wetland systems for wastewater treatment operating mechanisms and implications for design /

Heliotis, Francis Demetrios. January 1981 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 78-103).
82

Wetland restoration and port back-up facilities in Kam Tin

Tsui, Hiu-wai, Isabella, January 2009 (has links)
Thesis (M. L. A.)--University of Hong Kong, 2009. / Includes special report study entitled: Industrial constructed freshwater wetland for waterfowls and water treatment. Includes bibliographical references. Also available in print.
83

Examining cost effectiveness of actively and passively managed wetlands for migrating and wintering waterfowl in southern Illinois /

Pankau, Amanda K., January 2008 (has links)
Thesis (M.S.)--Southern Illinois University Carbondale, 2008. / "Department of Zoology." Keywords: Cost effectiveness, Illinois, Management, Waterfowl. Includes bibliographical references (p. 134-141). Also available online.
84

Wetland mitigation banking analysis & comparison of market mechanisms /

Cary, John Kenneth, January 2009 (has links) (PDF)
Thesis (M.A. in economics)--Washington State University, August 2009. / Title from PDF title page (viewed on Sept. 10, 2009). "School of Economic Sciences." Includes bibliographical references (p. 53-57).
85

Who is affected by wetland mitigation banking? : a social and geographic evaluation of wetland mitigation banking in Benton, Lane, Linn and Polk Counties, Oregon /

Brass, Timothy William, January 2009 (has links)
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 106-115). Also available online in Scholars' Bank.
86

Aquatic community organization in a diverse floodplain river fish fauna of the southeastern United States

Kennedy, Thomas Brian. January 2009 (has links) (PDF)
Thesis (Ph. D.)--University of Alabama, 2009. / Includes Vita. Title from PDF title page (viewed on May 25, 2010) Available through UMI ProQuest Digital Dissertations. Includes bibliographical references (leaves 225-235). Also issued in print.
87

Utility line siting and wetlands preservation

Quigley, Elin. January 1900 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 209-231).
88

Framework for remote sensing a complex wetland environment : evaluation of sensors and techniques /

Noonan, Mark. January 2005 (has links) (PDF)
Thesis (M.Phil.) - University of Queensland, 2005. / Includes bibliography.
89

Long-term anoxia tolerance in leaves of three wetland species (Acorus calamus L., Iris pseudacorus L., Vaccinium macrocarpon AIT)

Schlüter, Urte January 1999 (has links)
Anoxia tolerance of Acorus calamus, Iris pseudacorus and Vaccinium macrocarpon has been investigated by incubating whole plants under anaerobic conditions in the dark. Long-term survival of rhizomes under anoxia has been described in previous studies, but this study has shown that green leaves can also endure anoxia for prolonged periods. Leaves of A. calamus, I.pseudacorus and V.macrocarpon remained green and turgid under anoxia for up to 75d, 60d and 45d respectively. All growth processes ceased in leaves under anoxia. Anaerobic energy production via ethanol fermentation was active in all investigated plant organs as shown by the accumulation of ethanol. Low rates of anaerobic CO2 production indicated however, that the overall metabolic activity in the leaves was low under prolonged anoxia. The leaves seemed to adapt to the anaerobic conditions by an overall reduction of energy consumption rather than acceleration of the glycolytic rate. The demands for fermentable substrate were met by the mobilisation of internal carbohydrate reserves in leaves of V.macrocarpon. A.calamus and I.pseudacorus leaves contained only small amounts of carbohydrates, and these leaves possibly received carbohydrates from the stores in the rhizome. Prolonged anoxia considerably affected the leaf capacity for respiration and photosynthesis. After 28d of anoxia, respiratory capacity was reduced in A.calamus and V.macrocarpon by 80%, and in I.pseudacorus by 90-95%; this corresponded with a decline in the activity of the cytochrome c oxidase. The photosynthetic capacity of leaves was decreased after 28d of anoxia by 83% in A.calamus, by 97% in I.pseudacorus and by 80% in V.macrocarpon. The reduction in the photosynthetic capacity was accompanied by alterations in the chlorophyll fluorescence pattern indicating damage to the PSII reaction centre and the subsequent electron transport; only minor changes occurred in the chlorophyll content of anaerobic leaves. On return to air and light, recovery of respiration and photosynthesis occurred in the leaves, but species-specific differences were observed in the speed of recovery. Among the three investigated species, A.calamus leaves endured the anoxic conditions longer than leaves of the other two species; and on return to air, A.calamus leaves showed the most rapid recovery. A.calamus was characterised by efficient carbohydrate utilisation under anoxia. Cellular membranes and organelle ultrastructure appeared to be stable in A.calamus leaves for at least 28d of anoxia.
90

Assessment of the effects of stream channel incision on soil water levels, soil morphology and vegetation in a wetland in the Hogsback area, Eastern Cape, South Africa

Omar, Mohamed Yussuf January 2015 (has links)
Wetland degradation in the form of channel incisioning can significantly alter the hydrological functioning of a wetland. In this study in a small headwater wetland in the Hogsback area, Eastern Cape Province, the impact of channel incisioning on soil water levels and soil morphology was examined. A good correlation (R2 = 0.89) exists between the depth of channel incisioning and average water table depths in most of the 21 installed piezometers. In localised cases the upslope supply of water was in equilibrium with drainage from the piezometers. Although all the studied soils show hydromorphic characteristics, those continuously saturated close to the surface exhibit redox accumulations in oxygen supplying macropores, whereas gleyic colour patterns occur deeper in soils where the water table has been lowered by channel incision. The nature and occurrence of different hydromorphic soil indicators observed confirm the contribution of soil morphology as a valuable indicator of long-term average soil water conditions. The study evaluates the effects of hydrological processes on plant species composition and distribution in a Hogsback wetland. Twenty-four circular plots with a radius of 2 m were established between March and August 2013. Within each sample plot, the habitat information and species present were recorded including Braun-Blanquet cover-abundance value for each and every species present in the plot. Plant species were identified in the field and the unknown plant species were collected, pressed, oven-dried and identified at the National Herbarium, South African Biodiversity Institute (SANBI), Pretoria and Schonland Herbarium, Rhodes University, Grahamstown. A total of 39 taxa belonging to 19 families and 34 genera were recorded from the Hogsback wetland. Of the documented taxa, three were exotic and three endemic to South Africa, indicating diversity and dynamic nature of Hogsback wetland flora. Plant families with the highest number of species were: Poaceae (11 species), Asteraceae (5 species), Onagraceae and Cyperaceae with 3 taxa each. The low number of exotic plant species in Hogsback wetland (three taxa in total) indicates limited anthropogenic influence. Unique species recorded in Hogsback wetlands are three species that are endemic to South Africa, namely, Alchemilla capensis, Helichrysum rosum and Lysimachia nutans. Five main floristic associations were identified from the Hierarchical Cluster Analysis whilst Detrenched .Correspondence Analysis (DCA) identified four groups. The Canonical Correspondence Analysis (CCA) indicates that edaphic factors, particularly in an area covered with water, erosion category, organic matter content and water table depth were the most important environmental variables measured accounting for the vegetation pattern present in the Hogsback wetland.

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