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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.
51

Establishing Spatiotemporal Linkages Between Hydrological and Soil Physical Characteristics and Vegetation on an Ecological Preserve: Boca Raton, FL.

Unknown Date (has links)
In recent decades, ecohydrology has received renewed attention because of the impacts of groundwater withdrawal on ecosystems. Growing population and urban expansion in Palm Beach County, FL. place pressure to eradicate natural areas, such as Florida scrub habitats, and increase groundwater withdrawal. This study presents preliminary results of soil and hydrological characterization of an ecological preserve surrounded by changing land use. Soil moisture and water levels were monitored to assess the effects of precipitation as influenced by plants and soil analysis determined the suitability of current soil conditions for hosting native vegetation habitats. Hydrologic and soil conditions on the preserve fall within values expected for native Florida scrub habitats. Hydrologic response to precipitation varied due to factors including antecedent conditions and vegetation types. These results provide a better understanding of the interactions between soil proper ties, hydrologic cycle, and plants, and assist with establishing a baseline to monitor changes over time. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
52

The legal framework for managing the invasion of Ga-Riba Wetlands by poplar plant, Ga-Riba Village, South Africa

Lioma, Tshifhiwa Enocentia January 2010 (has links)
Thesis (M. Phil. (Environmental Law and Management) -- University of Limpopo, 2010 / According to the Ramsar Convention of 1971, Wetlands are areas of marshes, firm, peatlands or waterlogged. They are either natural or artificial. They have water that is static or flowing, fresh, brackish or salty and include areas of marine water with the depth, which at low tides does not exceed six meters. Wetlands are regarded as important ecological components of the natural environment because of their richness and ability to support life. Wetlands essentially catch, clean and preserve any water. They are able to reduce the severity of drought and floods by regulating a stream flow. They also control erosion and provide habitat for many different plant and animal species. Wetlands also serve as valuable source of water, fish and grazing for livestock. They are important nesting grounds for birds. Wetland resources are also known to be of socio-economic importance because they provide materials for furniture and craft’s work Ga-Riba wetlands are very important for the community of Ga –Riba because they provide them with food such as fish and birds. Some of the community members make baskets, hats and mats using wetlands grass. They also make pottery using clay from the wetlands. During winter the wetlands are used as areas where traditional initiation for Ga-Riba girls is perfomed. Some people own fields within the wetlands on which they cultivate vegetables, maize and other crops. They also use wetland as grazing areas for their domestic animals such as cattle and goats. The Ga-Riba wetlands are being invaded by one of the alien plant called Populus alba L (Poplar). This type of alien plant, like other alien plants disturbs the ecological stability of the wetlands. Findings of the tests conducted on soil and water indicated that Poplars are changing the nature of the soil and the water of the wetlands. Vegetation survey showed that, wetlands had less vegetation than they were supposed to. With regard to legal instruments to control the invasion of wetlands by alien plants, findings showed that there are insuffient legal instruments which can be utilized.
53

Linking the Ecological and Economic Values of Wetlands: A Case Study of the Wetlands of Moreton Bay

Clouston, Elizabeth, n/a January 2003 (has links)
This thesis examines the relationship between the underlying ecological values of wetlands and the economic values they produce. The importance of the roles that wetlands play is now well recognised yet losses continue at a global level. It is argued that one cause of wetland loss is a lack of awareness of the values of these systems due to inadequate information of the nexus between ecological functions and economic values. For example, the off-site, indirect benefits provided by wetlands have largely been ignored. This has led to an undervaluation of these ecosystems. The integration of ecological and economic values requires incorporating differing types of information and systems of value derived from differing disciplines with differing paradigms. To understand the differing disciplinary perspectives the thesis explores the ecological functions of wetlands and the economic goods and services that they provide. The functions and benefits of wetlands are linked at the ecological-economic interface. A consensus on the definition of ecological value could not be discerned within the discipline of ecology. Thus, a definition and index of ecological value is developed to demonstrate the attributes of coastal and wetland systems that provide for instrumental human benefits. These attributes include productivity, the ability to provide habitats for dependent species and the diversity of species and organisation they support. However, ecological information is not presently available to operationalise the index. The ability of economic techniques to capture this ecological value is then investigated. Three approaches for assessing non-market values (direct linkage models, revealed preference and stated preference models) are reviewed with respect to their ability to capture ecological value. An alternative biophysical approach, namely energy analysis, is also considered. The review suggests that it may be possible to measure ecological value using the contingent valuation method. The role of information in preference formation and willingness to pay bids is then investigated along with a number of other issues that need to be resolved before using the contingent valuation method. The wetlands of the case study area, Moreton Bay, Australia exhibit both ecological and economic values. The wetlands contribute approximately one-third of primary productivity in the Bay, provide habitat for a wide range of dependent species (including internationally recognised migratory wader birds) and have a diverse fauna with a relatively large number of endemic species. Economic values of the wetlands include both direct and indirect use values (for example, fishing, recreation, water quality improvements and storm buffering) and non-use values. Non-use values include the value in preserving the environment for future generations (bequest value) and the existence of vulnerable animals such as turtles and dugongs, which one may never expect to see. If consumers are willing to pay to preserve these animals, this is also a valid economic value. The economic technique of contingent valuation is tested to determine if it is possible to capture ecological value by providing respondents, selected by random sample, to a survey with the relevant information. A case study is undertaken in Moreton Bay to determine respondents' willingness to pay to improve water quality and hence protect the wetlands. To test the effects of differing types information, four different versions of the survey were sent to four groups of 500 respondents. Case A provided no extra information so it could be used as a control. Case B included information about the ecological values of the wetlands of Moreton Bay. Case C provided information about the economic use values of the wetlands in the Bay including direct and indirect use. Case D provided information about the non-use values of endangered species resident in the Bay that are dependent on the wetlands. The results indicate that the provision of different types of information influences willingness to pay. However, willingness to pay when provided with ecological information is not significantly different from willingness to pay when provided with other information. As it was not possible from the research undertaken to state that the contingent valuation method can capture ecological value, an alternative approach is proposed to link ecological and economic values. It is argued that ecologists and economists need to develop common aims and scales of assessment. Further, communication between the two disciplines can be enhanced through the use of agreed indicator terms. Through an iterative approach it should then be possible to understand the linkages between changes in indicators of ecosystem values and indicators of economic value.
54

Invasive species and compensatory wetland mitigation success

Ehorn, Casey H. January 2006 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2006. / Title from title screen (viewed 3/11/2010). Includes bibliographical references (leaves 41-53).
55

Wetland conservation in Hong Kong: evaluationof public-private-partnership model through the case study of Fung LokWai

Liu, Ka-chuen., 廖家傳. January 2012 (has links)
Conserving ecologically important sites under private ownership has long been the problem to the Government. In Mai Po and Inner Deep Bay Ramsar Site, wetland habitat comprises of a number of fishponds under private ownership. The land ownership issue hinders these fishponds from wetland conservation. Conventional conservation approach, which relies on nature reserve designation and land acquisition, is not always applicable due to huge financial implication. To resolve the issue, the Government launched Public-private Partnership Scheme in 2004, to encourage wetland conservation projects on private lands through integration of wetland conservation and development. In recent years, projects applied through Public-private Partnership Scheme have received strong objection from the public and green groups. They criticize the projects will impose potential impacts on wetland habitat and threats on biodiversity values. This study identified the inadequacies of Public-private Partnership Scheme and to analyze the root causes leading to ineffectiveness. The result of evaluation found several inadequacies in Public-private Partnership Scheme, including (i) ignorance of overall biodiversity values; (ii) weak linkage between conservation and development objectives and result in incompatible land uses; (iii) neglected the interest of powerless stakeholders in the design of trade-off and incentives; (iv) lacks of other policies, cross-departmental and regional planning supports; (v) uncertainty in long-term financial arrangement; and (vi) top-down and unidirectional participation process. These inadequacies are further categorized into five root causes leading to ineffectiveness of PPP scheme, including (i) limitations of incentive, (ii) lack of clear conservation targets, (iii) passive and rigid mechanism, (iv) top-down participation process, and (v) project-based policy. Based on these root causes, the Government’s motivation in conservation is much lag behind when compared to the public expectation. Its effort in facilitation is limited and critically influences the effectiveness of Public-private Partnership Scheme. Its passive and supervision role of the Government hinder the mechanism of Public-private Partnership Scheme search for better integration of wetland conservation and development. / published_or_final_version / Urban Planning and Design / Master / Master of Science in Urban Planning
56

Expanding partnership in design hybridization

Wong, Wai-shing., 黃偉誠. January 2013 (has links)
published_or_final_version / Architecture / Master / Master of Landscape Architecture
57

Visions of a wetland: linking culture and conservation at Lake Manyas, Turkey

Ari, Yilmaz 15 March 2011 (has links)
Not available / text
58

Wetland conservation in British Columbia: the role of environmental non-government organizations in Burns Bog

Delesalle, Bruno P. 11 1900 (has links)
This thesis examines the role of environmental non-government organizations in relation to the role and responsibility of government for wetland conservation in British Columbia. The role of a small community-based environmental organization called the Burns Bog Conservation Society in decisions about Burns Bog, a large privately-owned wetland located in the Lower Mainland, is analyzed. Drawing from a broad range of literature on environmentalism and conservation, the thesis begins with an historical account of the environmental movement, giving a broad view of environmental conservation and the role of environmental organizations. A typology of roles and analytical framework is subsequently derived from a study of environmental non-government organizations involved in managing water resources in British Columbia's Fraser River Basin. Three main roles, advocacy, supplemental and transformative, are discussed as they relate to activities prior to and during the Burns Bog Analysis, a provincially established land use study of Burns Bog. This research found that a small community-based environmental organization, through advocacy, can ensure that ecological integrity is not neglected as a result of poor planning and decision-making. The case study demonstrates that a small environmental organization can pressure governments to broaden their view of land-use and environmental issues, assuring more informed decision-making. An environmental organization can also supplement the regular roles and responsibilities of government, first by supplying a service that government is unable or unwilling to provide, and second by participating in and legitimizing consensus-based decision-making processes. The case study demonstrates how a small environmental organization can provide and review information and participate in creating options and solutions in land-use decisions. Finally, an environmental organization can influence, overtime, the fundamental restructuring of government planning and decision-making processes and transform the way society thinks and operates. The thesis concludes that environmental non-government organizations have an important role to play in ensuring the recognition and conservation of British Columbia's wetlands in government planning and decision-making processes; in informing and educating government and the public about ecological systems and their values; and in counter-balancing strong economic, political and development interests.
59

The use of magnetic susceptibility measurements to delineate wetlands in KwaZulu-Natal, South Africa.

Watson, Megan. January 2002 (has links)
The aim of this research was to investigate the possibility of using soil magnetic susceptibility to differentiate wetland soil from non0wetland soil, thereby enabling the identification of a wetland boundary. The initial methodology to test the viability of using magnetic susceptibility for wetland delineation was carried out at nine sites in three areas of Kwazulu-Natal, South Africa. Changes in vegetation were used to identify the permanently, seasonally and temporarily wet zones at each site to provide a quick indication of the various boundaries. At least one transect was studied at every site, extending from the outer edge of the temporary zone to the water's edge. Magnetic susceptibility readings, soil samples and/or elevations were taken in each zone. It was found that the magnetic susceptibility readings could be used to differentiate between the various wetland zones but boundaries were not identified due to the reconnaissance nature of the work, a specific protocol had yet to be discovered. This methodology was a reconnaissance phase to assess the potential of using soil magnetic susceptibility. A second methodology was designed specifically to identify a wetland boundary. The wetland zones were identified using vegetation indicators from the South African field procedure for delineating wetlands. Magnetic susceptibility readings were done on transects perpendicular to the suspected boundary and a critical value was identified. A magnetic susceptibility boundary was marked according to the critical value and verified by taking readings along transects parallel to it on both sides. The boundary was then identified using South African field procedure according to soil indicates. The soil data showed a similar boundary to the magnetic susceptibility boundary but indicated a 'boundary zone' of approximately l2m in width rather than a specific line. A final methodology was planned to improve the resolution of the magnetic susceptibility boundary. A grid was laid out over a strip through the wetland including the boundary area on both sides. This was to provide accurately spaced points at which to take magnetic susceptibility readings and elevations. The critical value, a value that separates wetland from non-wetland soil, was identified and verified using soil indicators. The field procedure was more difficult to carry out than using the magnetic susceptibility sensor, yet both methods identified the same boundary with a resolution of about 3m. This initial study demonstrates the potential for using magnetic susceptibility for wetland delineation. Although the results at the final site proved the method to be successful, it was not suitable for use at all sites and the results were often difficult to interpret. Limitations include factors such as plinthic horizons close to the soil surface and shallow, rocky soils. Thus further research is required before magnetic susceptibility can be used to delineate wetlands in KwaZulu-Natal, South Africa. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002.
60

Strategic environmental assessment design for wetland assessment and conservation policy development in an urban planning context

2015 June 1900 (has links)
This research advances Strategic Environmental Assessment (SEA) design and methodology for wetland assessment and policy development within an urban planning context. The thesis is a ‘manuscript-style’ and consists of three manuscripts, which collectively contribute to the overarching research purpose. The first manuscript presents and demonstrates a spatial framework for the application of SEA in the context of land use change analysis for urban wetland environment. The study aims to meet the needs for a proactive framework to assess and protect wetland areas more efficiently, and advance urban planning and development design. The proposed framework, adopting Geographic Information System and Remote Sensing approaches, presents a temporal evaluation of wetland change and sustainability assessment based on landscape indicator analysis. The results show that despite the recent extremely wet period in the Canadian prairie region, land use change contributed to increasing threats to wetland sustainability in the developing urban environment of the city of Saskatoon from 1985 to 2011. The second manuscript presents a scenario-based approach to SEA for wetland trends analysis and land use and land cover (LUC) modeling. Alternative future LUC was simulated using remote sensing data and city planning documentation using a Markov chain technique. Two alternatives were developed for LUC change and threats to urban wetland sustainability: a zero alternative that simulated trends in urban development and wetland conservation under a business as usual scenario, in the absence of prescribed planning and zoning actions; and an alternative focused on implementation of current urban development plans, which simulated future LUC to account for prescribed wetland conservation strategies. Results show no improvement in future wetland conditions under Saskatoon’s planned growth and wetland conservation scenario versus the business as usual scenario. Results also indicate that a blanket wetland conservation strategy for the city may not be sufficient to overcome the historic trend of urban wetland loss; and that spatially distributed conservation rates, based on individual wetland water catchment LUC differences, may be more effective in terms of wetland conservation. The results also demonstrate the challenges to applied SEA in a rapidly changing urban context, where data are often sparse and inconsistent across the urban region, and provides potential solutions through LUC classification and prediction tools to help overcome data limitations to support land use planning decisions for wetland conservation. The third manuscript presents an analytical approach to SEA, bridging strategic level assessment with operational planning and implementation. An expert-based strategic assessment framework was developed and applied to assess the potential implications of alternative wetland conservation policy targets on urban planning goals, and to identify a preferred conservation policy target. Site-specific algorithms, based on wetland area and wetland sustainability, were used to prioritize wetlands for conservation to meet policy targets within urban planning units. Results indicate a preferred wetland conservation policy target beyond which higher targets provided no additional benefit to urban development goals. The use of different implementation strategies, based on wetland area versus wetland sustainability, provides operational guidance and choice for planners to meet policy objectives within neighborhood planning units, but those choices have implications for local land use and wetland sustainability. Overall, the research contributes to the following aspects of SEA design and methodology: i) scoping processes to define the spatial and temporal context for SEA; ii) baseline assessment for analysis of environmental conditions and changes across space and/or over time; iii) methods to support the identification and evaluation of potential impacts of strategic alternatives; and iv) structured and systematic, quantitative assessment and decision-support tools for SEA that bridge strategic-level assessment with operational planning and implementation.

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