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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.
41

Influences of major storm events on backbarrier salt marsh change : Masonboro Island, Southeastern North Carolina /

Reimer, Beth A. January 2004 (has links)
Thesis (M.S.)--University of North Carolina at Wilmington, 2004. / Includes bibliographical references (leaves : 78-82).
42

An analysis of palustrine forested wetland compensation effectiveness in Virginia

Atkinson, Robert B. 19 October 2005 (has links)
Plans to construct a wetland to replace wetland losses has become a common feature of permit requests. The purpose of this project is to suggest a methodology for quantifying the effectiveness of palustrine forested wetland construction in Virginia. Wetlands constructed by ~ne Virginia Department of Transportation and the U.S. Army Corps of Engineers were surveyed and Wagner Road constructed wetland in Petersburg, Virginia was selected as the primary study site. Chapter One of the present study suggests a method for early assessment of revegetation success utilizing weighted averages of colonizing vegetation. An adjacent reference site was chosen that was in close proximity to the constructed site and was used for comparison. Results from the Wagner Road site and the reference wetland indicated that colonizing vegetation weighted averages provide a more sensitive measure of revegetation success than the methods described in the federal wetland delineation manual. / Ph. D.
43

South Africa’s response in fulfilling her obligations to meet the legal measures of wetland conservation and wise use

Lemine, Bramley Jemain January 2018 (has links)
Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2018. / South Africa is a signatory to the Convention on Wetlands of International Importance especially as Waterfowl Habitat of 1971 (referred to as the Ramsar Convention), which is an international convention making provision for protection and wise use of wetlands. Article 3 of the Ramsar Convention requires signatories to formulate and implement their planning to promote wise use of wetlands within their jurisdiction. “Wise use of wetlands” is defined as “the maintenance of their ecological character, achieved through the implementation of ecosystem approaches, within the context of sustainable development” (Birnie & Boyle, 2009: 674). The concept of wise use has been interpreted to mean sustainable development (de Klemm & Shine, 1999: 47; Birnie & Boyle, 2009: 49; Kiss & Shelton, 2007: 93; Birnie & Boyle, 2009: 674; Sands, 2003: 604), as it pertains to wetlands. Having said this, the National Environmental Management Act 107 of 1998 (NEMA) sets out principles of sustainable development that every organ of state must apply in the execution of their duties. Due to the wise use-sustainable development link, two NEMA principles have been considered to form the basis of this study, i.e. sections 2(4)(l) and 2(4)(r). The first principle places an obligation upon the state to ensure that there is intergovernmental coordination and harmonisation of policies, legislation and action relating to the environment (read to include a wetland); and the second principle is to ensure that specific attention in the management and planning are had to wetlands. Ironically, factors that are identified as hindering wise use include, but are not limited to: conflicting and incomplete sectoral law, absence of monitoring procedures, the absence of legal measures for environmental management of water quantity and quality. Therefore, an analysis will be undertaken to determine the extent to which South Africa’s legislative framework regulating wetland conservation is fulfilling the requirements for the promotion of wise use, through these two principles. Focus was had to environmental and related legislation, policies and regulations that promote and/or constrain wetland conservation and wise use. This study identifies the flaws within the law; and proposes streamlining and, where apposite, amendments to the existing legislative framework regulating wetlands in order for South Africa to fulfil her obligations.
44

Pollution status and assimilative potential of the wetlands at the Mai Po Marshes Nature Reserve, Hong Kong.

January 1997 (has links)
by Sam Shun-shun Lau. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 194-220). / Acknowledgments --- p.i / Abstract --- p.ii / Table of Contents --- p.iv / List of Plates --- p.vii / List of Tables --- p.viii / List of Figures --- p.xi / Chapter CHAPTER 1 --- Introduction / Chapter 1.1 --- Mai Po Marshes Nature Reserve (Hong Kong) --- p.1 / Chapter 1.1.1 --- Site description --- p.1 / Chapter 1.1.2 --- Ecological and conservation importance --- p.4 / Chapter 1.1.2.1 --- Local and international recognition --- p.4 / Chapter 1.1.2.2 --- Birds --- p.7 / Chapter 1.1.2.3 --- Gei wais and its wildlife --- p.10 / Chapter 1.1.2.4 --- Fishpond aquaculture --- p.20 / Chapter 1.1.3 --- Pollution sources and impacts --- p.22 / Chapter 1.2 --- Self-purification Capability of Wetland Ecosystems --- p.32 / Chapter 1.2.1 --- Principles and mechanisms --- p.32 / Chapter 1.2.2 --- Treatment efficiency --- p.38 / Chapter 1.3 --- Objectives and Outlines of the Present Study --- p.42 / Chapter CHAPTER 2 --- Water Quality of the Mai Po Marshes Nature Reserve / Chapter 2.1 --- Introduction --- p.45 / Chapter 2.2 --- Materials and Methods --- p.49 / Chapter 2.2.1 --- Water sampling and analyses --- p.51 / Chapter 2.2.2 --- Statistical analyses --- p.52 / Chapter 2.3 --- Results and Discussion --- p.52 / Chapter 2.3.1 --- Water quality in the Mai Po Marshes --- p.55 / Chapter 2.3.2 --- Spatial pattern of water pollution --- p.74 / Chapter 2.3.3 --- Temporal pattern of water pollution --- p.77 / Chapter 2.3.4 --- Correlation between various parameters --- p.79 / Chapter 2.4 --- Conclusions / Chapter CHAPTER 3 --- Nutrient and Metal Contaminationin Sediments of the Mai Po Marshes Nature Reserve / Chapter 3.1 --- Introduction --- p.81 / Chapter 3.2 --- Materials and Methods --- p.83 / Chapter 3.2.1 --- Sediment collection --- p.83 / Chapter 3.2.2 --- Laboratory analyses --- p.84 / Chapter 3.2.3 --- Statistical analyses --- p.84 / Chapter 3.3 --- Results and Discussion --- p.85 / Chapter 3.3.1 --- Pollution loads in sediments --- p.85 / Chapter 3.3.2 --- Spatial variation of contamination in sediments --- p.88 / Chapter 3.3.3 --- Temporal variation of contamination in sediments --- p.113 / Chapter 3.3.4 --- Vertical variation of contamination in sediments --- p.124 / Chapter 3.3.5 --- Correlation between various parameters --- p.131 / Chapter 3.4 --- Conclusions --- p.133 / Chapter CHAPTER 4 --- Behaviour of Contaminants in Sediments in a Shrimp-growing Gei Wai / Chapter 4.1 --- Introduction --- p.136 / Chapter 4.2 --- Materials and Methods --- p.137 / Chapter 4.2.1 --- Sediment collection --- p.137 / Chapter 4.2.2 --- General physico-chemical analyses --- p.139 / Chapter 4.2.3 --- Effects of salinity and temperature --- p.140 / Chapter 4.2.4 --- Effects of drying --- p.140 / Chapter 4.2.5 --- Toxicity assays --- p.141 / Chapter 4.2.5.1 --- Preparation of sediment extract for toxicity tests --- p.141 / Chapter 4.2.5.2 --- Microtox® toxicity testing --- p.141 / Chapter 4.2.5.3 --- Algal bioassay --- p.142 / Chapter 4.2.5.3.1 --- Algal culture --- p.142 / Chapter 4.2.5.3.2 --- Algal growth inhibition test --- p.142 / Chapter 4.2.5.4 --- Amphipod bioassay --- p.143 / Chapter 4.2.6 --- Statistical analyses --- p.144 / Chapter 4.3 --- Results and Discussion --- p.144 / Chapter 4.3.1 --- General properties --- p.144 / Chapter 4.3.2 --- Effects of temperature and salinity --- p.148 / Chapter 4.3.3 --- Effects of drying --- p.151 / Chapter 4.3.4 --- Toxicity assays --- p.154 / Chapter 4.4 --- Conclusions --- p.156 / Chapter CHAPTER 5 --- Self-purification Capability of Gei Wais at the Mai Po Marshes Nature Reserve / Chapter 5.1 --- Introduction --- p.159 / Chapter 5.2 --- Materials and Methods --- p.161 / Chapter 5.2.1 --- Sample collection --- p.161 / Chapter 5.2.2 --- Laboratory analyses --- p.161 / Chapter 5.2.3 --- Statistical analyses --- p.166 / Chapter 5.3 --- Results and Discussion --- p.167 / Chapter 5.3.1 --- Changes in water quality --- p.178 / Chapter 5.3.1 --- Removal efficiency --- p.185 / Chapter 5.4 --- Conclusions / Chapter CHAPTER 6 --- General Conclusions --- p.188 / References / Appendices
45

Wetland and water ecology centre in Tai O

Wan, Chi-lam, Floyd., 溫智霖. January 2005 (has links)
published_or_final_version / Architecture / Master / Master of Landscape Architecture
46

Aspects of the structure and functioning of the vegetation of the Hlatikulu Vlei.

Guthrie, Iain Andrew. January 1996 (has links)
Hlatikulu Vlei, situated in the foothills of the Natal Drakensberg, is one of the priority wetlands in KwaZulu-Natal, occupying an area of 733 Hectares. The importance of Hlatikulu Vlei lies in its functions to store water, regulate stream flow and attenuate floods, as well as to provide suitable habitat for wildlife and grazing for livestock. Hlatikulu Vlei is a threatened system and has suffered the effects of human mismanagement. Forty-nine percent of the vlei has been classified as disturbed or destroyed, mainly due to the construction of two large dams and past drainage of vlei to facilitate pasture planting. The effects of grazing and fire on the plant communities has been considerably less. Vegetation communities at Hlatikulu Vlei have similarities with those at Ntabamhlope Vlei. The main plant communities present at Hlatikulu Vlei are: vlei grassland, sege-meadows, bulrushes and reedswamp. Species compositions of the mixed sedge and grass sedge-meadow community have a notably higher species diversity than similar communities sampled at Ntabamhlope Vlei and the mires at Highmoor. Soil type and moisture content are shown to be the most significant environmental factors determining the distribution of plant communities and species within the vlei. A wetland re-establishment and rehabilitation programme in the Hlatikulu Crane and Wetland Sanctuary has been effective in allowing many wetland plants to become reestablished. The sanctuary communities bear greater similarity to the sedge and rush sedge-meadow community, than the mixed sedge and grass sedge-meadow communities that were originally present. This is also reflected in the seed bank. All three Southern African crane species (Blue, Wattled and Crowned Crane) and fourteen species of waterfowl have been recorded in the Hlatikulu Crane and Wetland Sanctuary since the wetland rehabilitation programme. The waterfowl play a role in the dispersal of seeds into the sanctuary, particularly those of Schoenoplectus decipiens and Eleocharis dregeana and are in part responsible for the return of certain wetland plants to the sanctuary. The flooding of soils, the fluctuating water level and the soil type related to hummocks and to channels are shown to be responsible for the location of Cyperus denudatus, Arundinella nepalensis and Aristida junciformis in differing positions in the channels and on the hummocks and are also responsible for the maintenance and functioning of the hummocks and channels. Seed banks on the hummocks are similar to seed banks in the channels, however the extant vegetation on the hummocks is distinctly different to that in the channels. Certain species represented in the channel seed bank are being excluded from surviving to maturity. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1996.
47

The conservation of coastal wetlands, especially the Mai Po marshes, in Hong Kong : problems and prospects /

Leung, Wai-hung. January 1996 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 71-73).
48

An exploration of teacher perceptions and actions to conserve wetlands in Kenya

Ndaruga, Ayub Macharia January 2004 (has links)
This thesis presents the findings of an exploration of teacher perceptions and actions to conserve wetlands in Kenya. It reports findings of a case study survey done with 54 primary school teachers from seven of eight Kenyan provinces. The teachers were sampled from a larger group of 242 teachers who participated in an in-service course on wetlands conservation. The in-service course engaged teachers in exploring various aspects of wetlands and how they could enhance their conservation using both formal and non-formal contexts. The survey approach was used in the research and was augmented with a reflective process. Survey tools used were the questionnaires and interviews. The reflective process entailed observation, document analysis, field notes and the researcher’s diary. Research data was analysed in several stages. The study revealed that teachers were users of local wetlands just like other members of their communities. The teachers differed among themselves with respect to their perceptions of the value and threats to their local wetlands. The teachers also differed in their perceptions of community awareness of their local wetlands. The teachers’ perceptions about environmental education and wetlands were not holistic. The teachers recorded various opportunities to foster wetlands conservation in their local contexts at school and the community. These were their fellow teachers, the pupils, the subjects taught, clubs, environmental days and the community. The relative importance of these opportunities differed among the teachers. Many teachers claimed being motivated to promote wetlands conservation using both formal and non-formal contexts. Their motivation was based on diverse aspects of wetlands, education and the in-service training they attended in 1999. However, the intensity of motivation differed for each aspect. For instance, at community level in-service training was a major motivator while the curriculum aspects were not mentioned at all. Teachers reported having involved their pupils and the community in several activities to conserve the local wetlands. These activities seemed to be dominated by theoretical approaches, eco-management activities and visits to wetlands. There was little evidence to indicate the teachers being engaged in addressing the implications for sustainability of the perceived local wetland values and threats. The activities reported also failed to show engagement with local environmental problems as a deliberate proactive process involving exploration, discussion, action taking and reflection. Most of the activities were presented as one off activities rather than as a cyclic continuously improving series of interventions. The overall scenario presented by the teachers is one of inadequacy in addressing the sustainable use of wetlands. Teachers suggested various constraints that affect their realisation of environmental education for wetlands sustainability. The constraints traverse various aspects of the economic, biophysical, political, educational and social aspects of wetlands conservation. The study suggested the need for teachers to treat their contextual and personal conceptions as problematic rather than as simplistic or linear issues and to formulate ways to address them. This study suggests a potential but under-utilised opportunity to promote wetlands sustainability. The overall picture generated by the data in this study is a need to consider wetland training for teachers that integrates the holistic aspects of wetlands as well as the environmental education for sustainability perspectives grounded in local contexts.
49

Natural impressions: a centre for wetland, estuary & marine conservation in the Isimangaliso Wetland Park

Govender, Kimesha January 2016 (has links)
Climate change is a clear indication that humanity’s innate affiliation with nature has been suppressed, and that our detrimental anthropogenic activities on the earth’s natural resources and systems, have exceeded the earth’s ecological capacity to cope and regenerate. This threatens environmental sustainability, which subsequently has social and economic implications. Environmental conservation is humanity’s aim towards re-affiliating its deep rootedness in nature, in order to ensure a sustainable co-existence with other species and natural systems, and thus convince responsive lifestyles, which allows humanity to match natural-resource extraction to the rate at which the earth can regenerate. The role of environmental sustainable architecture, towards mitigating humanity’s impact on global warming, still leaves a disparity between human relationships and interactions with the natural environment. The notion of a phenomenology-guided design inquiry, an application of enhanced multi-sensory experiences is identified, to re-affiliate humanity with nature and to provoke a sense of urgency for greater protection of the natural environment, through an immersive experience of enhanced human-nature interactions with nature. Furthermore, this notion is applied in the programme of eco-tourism and qualitative ecological research; the proposed site choice; the concept design approach and technical resolution of the project. The research recognises the conservation of sensitive ecosystems such as the iSimangaliso Wetland Park in northern KwaZulu-Natal, as one of the core strategies for environmental sustainability, and its appropriateness as a site for immersed experiences with nature and the sharing of ecological knowledge for the benefit of the wider communities in South Africa and internationally. The research proposes an environmentally responsible and contextually appropriate architectural design, for a wetland, estuary and marine conservation centre in the iSimangaliso Wetland Park. Furthermore, the programme responds to the key contextual issues concerning the park by assisting with the ecological conservation and growth, as well as the social and economic sustainability of the iSimangaliso Wetland Park and surrounding communities. This is achieved by proposing an architectural programme which functions as an interface and mediator for the key issues concerning the park, that is of research, education, tourism and community participation, through which the most concerning issue of ecological conservation occurs.
50

Quantifying wading bird resource selection and nesting effort: a tool for the restoration of pulsed ecosystems

Unknown Date (has links)
Understanding the link between indicator species and their environment is imperative to managing and conserving anthropogenically-altered ecosystems. Seasonally-pulsed wetlands are uniquely complex ecosystem where water-level fluctuations shape trophic interactions. Anthropogenic manipulation of water-level fluctuation threatens the integrity of these systems worldwide. Wading birds, a group of species sensitive to landuse changes and fluctuating habitat conditions, serve as important indicators for wetland health. I used wading birds in the Everglades, as a model system to address the challenges of environmental restoration within an ecosystem heavily impacted by anthropogenic activities. Specifically, I 1) identified the nesting response of Great Egret (Ardea alba), White Ibis (Eudocimus albus), and Wood Stork (Mycteria americana) to hydrologically-mediated changes in food availability and 2) quantified spatiotemporal foraging-habitat selection of Great Egrets, White Ibis, and Wood Storks to fluctuating hydrologic conditions. Collectively, model selection results suggest food availability, generated through dynamic hydrological conditions, is a strong predictor of the abundance of nesting birds in a given year. Great egret and white ibis produce the highest nests numbers in years when the frequency of days of rising water is low. Wood stork nest numbers are the highest in years with high prey production coupled with continuous prey availability. My study of resource selection indicated wading birds select foraging sites based on similar hydrologic parameters, but the response varies by species. Wood storks are more likely to forage in shallow cells (< 10 cm) drying with high recession rates (0.5-1.5 cm/day), and long time since last drydown (600 days). White ibises selected foraging cells with relatively shallow water depths (0-15 cm), intermediate recession rates (0.5-1.0 cm/day), and long time since drydown (600 days). Great egrets selected foraging cells with a wider range of water depths (0-20 cm) where recession rates were lower (0.5 cm/day). All species are more likely to forage in cells where water has not increased by more than 3 cm in the previous two weeks. These differences in resource selections correspond to morphological and behavioral differences in the species, whereby wood storks were more constrained hydrologically and would be more affected by water-level manipulation. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

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