Siga este link para ver outros tipos de publicações sobre o tema: Wetland conservations.

Teses / dissertações sobre o tema "Wetland conservations"

Crie uma referência precisa em APA, MLA, Chicago, Harvard, e outros estilos

Selecione um tipo de fonte:

Veja os 50 melhores trabalhos (teses / dissertações) para estudos sobre o assunto "Wetland conservations".

Ao lado de cada fonte na lista de referências, há um botão "Adicionar à bibliografia". Clique e geraremos automaticamente a citação bibliográfica do trabalho escolhido no estilo de citação de que você precisa: APA, MLA, Harvard, Chicago, Vancouver, etc.

Você também pode baixar o texto completo da publicação científica em formato .pdf e ler o resumo do trabalho online se estiver presente nos metadados.

Veja as teses / dissertações das mais diversas áreas científicas e compile uma bibliografia correta.

1

Chan, Chung-san. "The future of the Deep Bay Wetlands, Hong Kong /". Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18735927.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
2

Johnson, Patricia Ann. "The status of freshwater compensatory wetland migration in Washington State". Online pdf file accessible through the World Wide Web, 2004. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Johnson_PAMESThesis2004.pdf.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
3

Ari, Yilmaz. "Visions of a wetland : linking culture and conservation at Lake Manyas, Turkey /". Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3025135.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
4

Begum, Fatema. "Mangrove wetlands in Bangladesh /". Title page, table of contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ENV/09envb418.pdf.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
5

Soule, Ann Catherine. "Deficiencies in wetland project planning, review and implementation". Thesis, The University of Arizona, 1990. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1990_637_sip1_w.pdf&type=application/pdf.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
6

Maulan, Suhardi. "A Perceptual Study of Wetlands: Implications for Wetland Restoration in the Urban Area in Malaysia". Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/26966.

Texto completo da fonte
Resumo:
The restoration of natural wetlands is a wonderful, noble and pragmatic idea, but such efforts often meet resistance from certain segments of society. One reason for this is that the public perceives the environment in different ways than do the experts, such as landscape architects and land managers. This dissertation analyzes peopleâ s preferences for wetlands in comparison to those of landscape architects. It specifically studies the conflict about the wetland restoration program in the Malaysiaâ s Kelana Jaya Municipal Park. This dissertation is based on data obtained from a preference survey using photo questionnaires that polled both the publicâ s and landscape architectsâ group preferences for wetlands. The data was analyzed using the Content Identifying Method (CIM) to determine group preferences for wetlands and factors that influence these preferences. Park managers from several local authorities also were interviewed to determine their expectations of public preferences and attitudes toward wetland restoration and public participation. The public and landscape architects have significantly differed in stated preferences for wetlands. The public strongly prefers park-like landscapes that demonstrate human influences and provide the potential for human involvement; in contrast, landscape architects prefer natural wetlands that are visually pleasing, with well-defined spaces, visual coherence, and visual complexity. In addition, park managers did not accurately predict the publicâ s view of wetlands. Their prediction was similar to landscape architectsâ preferences. Attitudes toward wetland activities and safety, knowledge about wetland benefits, the motivation to use urban natural open spaces, and familiarity with nature significantly affected the publicâ s preferences. Further, the motivation to use urban natural open spaces was the best predictor of publicâ s preferences. The primary implications of this dissertation are that environmental education should be a core activity in changing peopleâ s perceptions of natural wetlands and that opinions of local people should be incorporated in many aspect of wetlands restoration, planning, design, and policymaking, especially in Malaysia.
Ph. D.
Estilos ABNT, Harvard, Vancouver, APA, etc.
7

Clouston, Elizabeth, e n/a. "Linking the Ecological and Economic Values of Wetlands: A Case Study of the Wetlands of Moreton Bay". Griffith University. Australian School of Environmental Studies, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030828.140330.

Texto completo da fonte
Resumo:
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.
Estilos ABNT, Harvard, Vancouver, APA, etc.
8

Clouston, Elizabeth. "Linking the Ecological and Economic Values of Wetlands: A Case Study of the Wetlands of Moreton Bay". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/366973.

Texto completo da fonte
Resumo:
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.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
Full Text
Estilos ABNT, Harvard, Vancouver, APA, etc.
9

Mengel, Doreen C. "Amphibians as Wetland Restoration Indicators on Wetlands Reserve Program Sites in Lower Grand River Basin, Missouri". Thesis, University of Missouri - Columbia, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13850742.

Texto completo da fonte
Resumo:

Globally, amphibians have suffered dramatic population declines in the past twenty years with habitat destruction implicated as the primary threat. The Natural Resources Conservation Service’s Wetlands Reserve Program (WRP) restores wetlands on marginal agricultural land and is a means to restore the spatio-temporal wetland habitat required by amphibians to prevent, reverse, or stabilize declining population trends. The goal of WRP is “to achieve the greatest wetland functions and values, along with optimum wildlife habitat, on every acre enrolled in the program.” Functions and values are defined as the hydrological and biological characteristics of wetlands. A key unanswered question is to what extent is this goal being achieved? Amphibians enable quantifying the WRP goal due to their life-history requirements and explicit incorporation of their habitat needs into WRP plans. My research goal was to determine if hydrological and biological wetland characteristics had been restored to WRP sites in the Lower Grand River basin, north-central Missouri, based on distribution, recruitment success, and relative species richness estimates for members of a regional species pool. I identified three design strategies applied to WRP sites over time: walk-away, maximize hydrology, and naturalistic; the latter emphasizing restoring process as well as structure; and evaluated if design strategy was a useful covariate for restoration efforts. I encountered 10 amphibian species representing 59% of the regional species pool. Design strategy was not a predictive site-level covariate as sites within all three design strategies had varying hydrological wetland conditions resulting in greater habitat heterogeneity than anticipated on maximize hydrology and walk-away sites and less than anticipated on naturalistic sites. Amphibian detections occurred across all sites resulting in no difference among design strategy as the degree of heterogeneity in habitat conditions at the within site-scale demonstrated that amphibians were responding to ecological conditions that occur at a finer resolution than site. Results, irrespective of design strategy, indicate seven of the detected species or groups were widely- distributed, two were moderately- distributed, and two were sparsely distributed on WRP sites indicating hydrological wetland characteristics have been restored to sites given the moderate- to wide-distribution of species associated with both seasonal and permanent wetlands. Although species were successfully recruiting young into adult populations, only leopard frogs had high estimates of recruitment success whereas the remaining species had moderately high to moderate to low recruitment estimates indicating biological wetland characteristics are somewhat lacking to lacking for these species. Results from the relative species richness assessment indicate that, whereas 74% of the sites provided some degree of wetland habitat for members of the regional species pool over the course of the field season (7 March – 19 September), 52% of the sites lacked suitable habitat conditions during the peak of amphibian breeding and larval development (May through July). Targeting management actions that result in suitable seasonal wetland habitat conditions (shallow, vegetated wetlands that gradually dry by mid-to late-summer) throughout the time needed for species to complete their life history requirements is one method to increase the biological wetland value of restored WRP sites. Results show the value of WRP at conserving and restoring river-floodplain amphibians; however, achieving optimum wildlife habitat on every enrolled acre will be difficult at a site-level scale as habitat requirements, although overlapping, vary widely for the full range of species. Providing for all species in the regional species pool requires sites that transverse both the longitudinal and lateral floodplain gradient. If WRP is to realize its full potential, there must be recognition that optimum wildlife habitat can be defined at multiple spatial and temporal scales that match the landscape setting. Optimum wildlife habitat at a wetland scale is not the same as optimum wildlife habitat at the floodplain scale. The intent of WRP is to convert marginal, flood-prone agricultural lands back into wetlands so enrollment of lands located outside the active floodplain may be impracticable or unrealistic. Whereas attaining optimum wildlife habitat on every acre enrolled in the program may not be an achievable objective, providing optimum wildlife habitat for members of a regional species pool within an appropriately defined geography that includes both a longitudinal and lateral gradient represents an objective that is both desirable and attainable.

Estilos ABNT, Harvard, Vancouver, APA, etc.
10

Elliott, Katherine Louise. "An analysis of the Federal wetlands regulations influencing construction development". Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/21437.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
11

Atkinson, Robert B. "An analysis of palustrine forested wetland compensation effectiveness in Virginia". Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39970.

Texto completo da fonte
Resumo:
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.
Estilos ABNT, Harvard, Vancouver, APA, etc.
12

Painter, Luke. "Growth rates and the definition of old-growth in forested wetlands of the Puget Sound region". Online pdf file accessible through the World Wide Web, 2007. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Painter_L%20MESThesis%202007.pdf.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
13

Wiebusch, Roger Kent. "Causes of the decline in the loss of vegetated palustrine wetlands in the U.S. 1955 - 2009". OpenSIUC, 2015. https://opensiuc.lib.siu.edu/dissertations/1014.

Texto completo da fonte
Resumo:
By 1980, the United States had lost over 50 percent of its original wetland resources. The U.S. National Wetland Inventory estimates that 95 percent of annual wetland losses since 1955 occurred to palustrine wetlands. The majority of these losses occurred to the three types of palustrine vegetated wetlands: emergent, forested, and shrub. The primary cause for wetland losses from the mid-1950s to the mid-1980s was agricultural conversion supported by federal agricultural policies, especially the Agricultural Conservation Program that provided significant direct and indirect support for wetland conversions. The rate of converting wetland to agriculture has declined since the mid-1950's with a significant decrease occurring between the mid-1970s and mid-1990s. Statistical analysis using correlation, regression and principal component analysis was performed to identify the major contributory factors in loss rates in the Midwest, Lower Mississippi River Valley and the Southeast United States. The variables considered are: Swampbuster provisions of the Food and Security Act of 1985, Conservation Reserve Program enrolled acreage and rental rates, Wetland Reserve Program and The Clean Water Act Section 404 permits; prices of corn, soybeans and wheat; and the percent of wetlands remaining. The results indicated agricultural policies and Clean Water Act Section 404 permits and wetland loss rates were negatively correlated and prices of corn, soybeans and wheat were positively correlated. The percentage of wetlands remaining, were also positively correlated with loss rates. Taken together, the selected agricultural policies, Section 404 permits, commodity prices and percent of wetland remaining, explain 96 percent of the variance in wetland loss rates and 94 percent of the agricultural losses nationally. These results are consistent, with minor variations, across geographic wetland strata and wetland types. Regional differences exist in the major type of wetland losses; emergent wetland losses were more prevalent in the agricultural Midwest, with forested wetland losses concentrated in the Lower Mississippi River Valley and the Southeast United States. The results of this research reflect the intricate relationships between federal legislation, regulatory programs, legal decisions, economic factors, and changes in society's view and understanding of the importance of wetlands and the need to merge conservation programs with agricultural policies. Economic factors exert a significant impact in decision-making of whether to convert or conserve wetland resources. The economic feasibility of installing drainage system to make wetlands farmable depends upon the relationship of capital investment cost and crop prices. Commodity prices impact decisions regarding enrollment into the Conservation Reserve Program and the Wetland Reserve Program; higher commodity prices can make conversion more profitable but low crop prices will make these programs more appealing economically. The Swampbuster provisions are effective in conserving wetlands if the economic penalties are significant to the individual farmer. The policy, legal and commodity variables were used to create models that explain the inter-relationship between agricultural economic factors, policy impacts and commodity prices. The models indicate how the variables could affect decision-making in determining whether to convert or conserve palustrine vegetated wetlands; increased commodity prices coupled with lower conservation program payments could jeopardize wetland conservation efforts and result in increased wetland loss rates due to increased wetland drainage and conversion.
Estilos ABNT, Harvard, Vancouver, APA, etc.
14

Newbold, Stephen Carlisle. "Targeting conservation activities : cost-effective wetlands restoration in the Central Valley of California /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

Texto completo da fonte
Resumo:
Thesis (Ph. D.)--University of California, Davis, 2002.
Degree granted in Ecology. Includes bibliographical references (leaves189-199). Also available via the World Wide Web. (Restricted to UC campuses)
Estilos ABNT, Harvard, Vancouver, APA, etc.
15

e, Souza Reis Vanessa. "Integrated conservation planning for river-wetland mosaics". Thesis, Griffith University, 2018. http://hdl.handle.net/10072/381063.

Texto completo da fonte
Resumo:
Wetlands are highly productive and biodiverse ecosystems and provide many ecosystem services for humans. They are a key component of the natural hydrological cycle and are involved in important biophysical processes, such as the exchange of sediments, nutrients and organisms which influence water quality and functional integrity of rivers. Owing to their high productivity, fertile soils, and importance for water provision, many of the world’s wetlands have a long history of human occupation and intensive use. As a consequence, extensive degradation and modification of wetland ecosystems by human activities has occurred worldwide. In seasonal wetlands, the timing and duration of soil saturation and inundation are the main determinants of geomorphological and ecological characteristics that give rise to a great variety of ecosystem types. Although the ecological functioning of seasonal wetlands relies on this strong temporal driver, wetland conservation decisions often are based on static maps of wetland boundaries that fail to depict their dynamic hydrological variability and connectivity. Another challenge in wetland conservation is accounting for multiple dimensions of wetland connectivity in the riverine landscape. For example, the ecological integrity of large floodplain rivers, such as the Amazon River system, depends on the maintenance of a diversity of waterbodies with variable degrees of connectivity between themselves and with the main river channel. Lack of adequate frameworks in wetland conservation planning to account for these different sources of connectivity can compromise the long-term persistence and integrity of wetlands in the landscape. This is a critical issue because human activities such as land use change, levee construction and flow regime alterations can lead to the disruption of connectivity, thus greatly affecting wetlands downstream and compromising their ecological integrity and provision of ecosystem services. The overall objective of this thesis is to develop a new framework of systematic conservation planning for river-floodplain ecosystems that adequately accounts for the multidimensional connectivity of wetlands in riverine landscapes. To achieve that, I have combined the use of remote sensing tools at multiple scales with statistical modelling and spatial planning to address three main issues in wetland conservation: (1) the lack of comprehensive assessments to determine conservation status of the world’s wetlands, (2) the limitations of representing wetland seasonality in traditional static maps that often delineate wetland boundaries based on minimum or maximum extents, and (3) the lack of adequate spatial frameworks in systematic conservation planning to deal with wetland connectivity in the riverine landscape. To address the first issue, I developed a global-scale portrait of the threats and protection status of the world’s inland wetlands. This was achieved by combining a global map of inundation extent derived from satellite images with data on threats from human influence and on protected areas. Inland wetlands represent only ~6% of the world’s land surface, and about 89% of these areas have no formal protection (as defined by protected areas IUCN I-VI and Ramsar sites). Wetland protection was variable across the world, ranging from 20% in Central and 18% in South America to only 8% in Asia. Particularly high human influence was found in Asia, which contains the largest wetland area of the world. High human influence was observed in wetlands even when they are within protected areas. This demonstrated that terrestrial protected areas do not always adequately protect wetland ecosystems and underscores the urgent need for more effective conservation measures worldwide. To tackle the second issue, I undertook a hydrological classification of the Amazon wetlands according to the timing and duration of inundation. The classification was based on remotely sensed monthly inundation maps, and also investigated how precipitation regimes affect wetland distribution and hydrological dynamics. Permanently inundated wetlands accounted for the largest area and were mainly floodplains located in the lowlands of the catchment. Seasonally inundated wetlands varied greatly in duration of inundation over the course of the year, ranging from one to nine months. Distinct seasonal timing was detected among large wetland complexes, reflecting rainfall regimes as well as time lags for recession and drying. For example, inundation in the extensive Llanos the Moxos region of the southern Amazon was protracted and lasted well after the rainy season, compared to the Roraima region of the northern Amazon where inundation was shorter and tracked the rainy season. This integration of inundation dynamics into wetland classification captures regional differences in timing and duration of inundation in major wetlands of the basin that should be considered in conservation planning and other ecological applications. Finally, I developed a new framework in systematic conservation planning to account for the multidimensional connectivity of floodplain river ecosystems and provide more adequate protection of wetlands, and applied this to the entire Amazon basin. Accounting for both within-floodplain and longitudinal river connectivity in the riverine landscape, the new spatial framework combines two types of planning units – wetland hexagons and subcatchments – which were connected using two distance-based approaches. Four prioritization scenarios were tested comparing only within-floodplain connectivity versus integrated within-floodplain and upstream connectivity and resulted in varying levels of reduced impact. When only considering within-floodplain connectivity, propagation of impacts from the surroundings and upstream catchment was ignored. In contrast, the scenario that included both within-floodplain and longitudinal river connectivity agglomerated subcatchments around the priority wetlands, achieving catchment integration that efficiently reduced impact. This thesis contributes to the field of wetland conservation by integrating cutting edge data science with novel planning methods. It highlights the conservation status of inland wetlands and quantifies global and continental threat patterns. The innovative classification approach that spatially represents seasonal patterns in wetland inundation can be used to explore the role of seasonality on the ecological characteristics and functions of different wetlands complexes. It represents an important step towards including temporal dynamics in wetland conservation planning and management. Furthermore, including the multidimensional connectivity of wetlands in a comprehensive spatial framework can offer more ecologically meaningful protection to floodplains. This is crucial to plan for safeguarding wetland ecosystem functions at the landscape context. Finally, the use of global remotely sensed data sets make all approaches presented here readily adaptable for use in other regions of the world.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
Full Text
Estilos ABNT, Harvard, Vancouver, APA, etc.
16

Ndaruga, Ayub Macharia. "An exploration of teacher perceptions and actions to conserve wetlands in Kenya". Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1003417.

Texto completo da fonte
Resumo:
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.
Estilos ABNT, Harvard, Vancouver, APA, etc.
17

Donaldson, Lynda. "Conservation and ecology of wetland birds in Africa". Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/31812.

Texto completo da fonte
Resumo:
Conservation managers worldwide are increasingly faced with the challenges of managing and protecting fragmented landscapes, largely as a consequence of human activities. Over recent decades, ecological theory has made a significant contribution to the development of landscape-scale conservation and practice. However, recommendations accounting for what is practically achievable in the modern-day landscape are currently lacking, while criteria for conservation planning and prioritisation continue to neglect the role of habitat networks at the required spatial scale for the long-term persistence of biodiversity. In this thesis, I test and apply ideas surrounding the complexities of managing and conserving species in a landscape context, using a suite of bird species endemic to papyrus (Cyperus papyrus) swamps in East and Central Africa as a model system. In the face of large-scale habitat loss and degradation, practical measures that account for the fragmented nature of this system, the needs of multiple specialist species, and the reliance on this habitat by local people, are urgently required. I first review the concepts originating from reserve design theory to provide a decision-making framework for those involved in landscape-scale conservation amid 21st century challenges to biodiversity, highlighting the key principles to be considered for informed choices to be made. Second, I show that the needs of local people can be compatible with conservation planning in the tropics, and may play an important part in maintaining habitat quality for species residing in historically disturbed landscapes. Third, I develop a novel framework to make an explicit link between metapopulation dynamics and conservation planning. Despite differences in the patch-level dynamics of individual species, areas of habitat where populations of multiple species are resistant to extinction, and resilient because of high chances of (re)colonization can be identified, highlighting where resources could be invested to ensure species have the capacity to respond to future change. Finally, I simulate the metapopulation dynamics of the papyrus-endemic birds to demonstrate that the optimal conservation strategy for the long-term persistence of all species residing in a network depends on the characteristics of individual species, and the total area that can be protected. Overall, this thesis develops and tests the ecological theory used in spatial conservation planning, emphasising the importance of habitat disturbance and interspecific ecological differences for the effective management of habitat networks. The results increase the evidence base for the conservation of wetland birds in Africa, as well as for species residing in fragmented landscapes more generally.
Estilos ABNT, Harvard, Vancouver, APA, etc.
18

Lemine, Bramley Jemain. "South Africa’s response in fulfilling her obligations to meet the legal measures of wetland conservation and wise use". Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2844.

Texto completo da fonte
Resumo:
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.
Estilos ABNT, Harvard, Vancouver, APA, etc.
19

Wan, Chi-lam Floyd. "Wetland and water ecology centre in Tai O /". View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B3461235X.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
20

Mekiso, Feleke Abiyo. "Hydrological proceses, chemical variability, and multiple isotopestracing of water flow paths in the Kudumela Wetland- Limpopo Province, South Africa". Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1006153.

Texto completo da fonte
Resumo:
The hydrology of the Kudumela Wetland, Limpopo Province of South Africa was studied from November 2005 to April 2007, involving both fieldwork and laboratory analyses. This study presents the results of an investigation of the hydrology of the Kudumela Wetland in South Africa, and its contribution to dry season flow in the Mohlapitsi and Olifants Rivers. Initially, 40 Piezometers were installed along seven transects and water levels monitored in order to understand water table level characteristics (fluctuations) with time. Water levels in transects one, three, the right bank portion of transect four and transect six showed fluctuations. Transect two, the left bank portion of transect four and transect five did not show significant temporal changes. The relationships between piezometer water levels, rainfall in the study area and stream flow observed at a river gauging station are not clear. The river within the wetland is a gaining stream because the water table level elevation is above that of the river. This indicates that the wetland is feeding the river. The northern part of the wetland (T1 and T2) is affected by artificial drains and most of the piezometers closest to the river channel showed the lowest variations. The relationships between rainfall, groundwater, and surface water at this site shows that stream flow did not respond quickly to precipitation as expected, even in months when rainfall increased (for example, 74 and 103mm during 08/02/06 and 18/02/06 respectively), and the groundwater levels did not show fluctuations, indicating that groundwater responds gradually to precipitation, and that the relationship between rainfall, groundwater and surface water is complex. The environmental stable isotopes (deuterium and oxygen-18) and the radioactive isotope (tritium) were analyzed, along with field observations of electrical conductivity (EC), pH, total alkalinity (Talka) and some major and minor dissolved ion analyses for tracing water dynamics in the study area. A total of 39 water samples was taken and analyzed from boreholes, auger holes, right bank and left bank drains, various points along the river and springs in four sampling visits to the wetland. The results did not clearly provide a temporal record of isotope and chemical variations in the various sources. Results from the most extensive sampling survey in April 2007 provide the most comprehensive overview of hydrological relationships. Clustering of the stable isotope data suggests that the water samples of upstream and downstream river, auger holes further south and most drains clustered together suggesting a common water source and almost all samples fall above the global (GMWL) and local (Pretoria MWL) meteoric water lines, while some fall between the global and Pretoria meteoric water lines. Six representative water samples were analyzed for major ion concentration. Both cation (Ca, Mg, K, and Na) and anion (HCO3, SO4, Cl, and NO3) analyses in November 2007 confirmed conclusions reached from field observations. The analysis shows that a single type of water (Ca, Mg-HCO3) is involved in the study area. In almost all major ion plots, the right bank drains, upstream river and downstream river samples grouped together in a single cluster. As the means for reliable river flow measurements were not available, except for the gauging station at the outlet of the valley, rough, semi-quantitative estimates were made during several field visits. These, suggest considerable losses of river flow into the gravel/boulder beds at and below a gabion dam at the head of the valley. Three major and several other left bank springs and right bank drains at transects T1 and T2 contributed to the river flow at all times. Along with the isotopic and chemical evidence, these observations have lead to a hypothesis that river water enters the wetland and flows back to the Mohlapitsi River through boulder beds underlying the wetland and through drains on the surface of the argillaceous aquitard covering the more conductive boulder beds. Deeper dolomitic groundwater does not appear to contribute to the water balance at least in the northern half of the wetland. Although environmental isotope and hydrochemistry results may not unequivocally prove this hypothesis they do not contradict it.
Estilos ABNT, Harvard, Vancouver, APA, etc.
21

Lee, Kai-tung. "A review of freshwater wetland conservation in Hong Kong : policy and practice /". View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37120566.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
22

Wong, Sui-kan. "A critical review of wetland protection in Hong Kong /". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23424850.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
23

Chung, Hung-fat. "An investigation of the role of Mai Po Nature Reserve from a conservation and education perspective /". Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22264772.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
24

Lau, Lai-ki. "Effectiveness of planning and management on Ramsar site in Hong Kong /". Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22284710.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
25

Chiaravalloti, R. M. "Local communities and conservation in the Pantanal wetland, Brazil". Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1551634/.

Texto completo da fonte
Resumo:
This thesis aims to develop the understanding of inland floodplain fisheries. It focuses on the Western Border of the 160,000Km2 Pantanal wetland in Brazil, using participant observation, semi-structured interviews, participatory mapping, and a critical exploration of Systematic Conservation Planning meant to optimize land use planning for biodiversity conservation. Following the introduction, study site and methods chapters, the first data chapter presents a description of fishing communities’ social structure, livelihood and history of resource use and occupation. New information on this hitherto unstudied group explores their mobile way of life and their physical displacement during the creation of Protected Areas. The second data chapter analyzes the current management of inland fisheries, examining evidence for claims around overfishing by local communities. The results do not support narratives of overfishing. Instead, fishers’ customary use is characterized by mobile patch use, territory, and reciprocity. These map onto features of this dynamic ecosystem, such as the flood pulse and the presence naturally unexploitable reserves, in ways likely to create sustainable use. The discussion explores why these features may play equally important roles in other floodplain fisheries. The third data chapter discusses tenure and property in floodplains, using as case in point the conflict among Pantanal Protected Areas managers, fishers and state prosecutors over floodplain ownership. A multidisciplinary approach to resource use, access and property, drawing on economics, anthropology and ecology, may help understand tenure in floodplains so as to help management policies mesh better with local realities and resolve conflicts. The final data chapter critically examines prioritization solutions seeking to promote socio-ecological development. Applying Systematic Conservation Planning in the Pantanal case study shows the assumption of fixed set-aside areas is incompatible with the ever-changing nature of the Pantanal and the needs of local fishers. Dynamic socio-ecological systems, such as floodplain fisheries, demand continual adaptation.
Estilos ABNT, Harvard, Vancouver, APA, etc.
26

Zoete, Toivo. "Conservation of wetland functions in an environment of regional growth and change : melaleuca quinquenervia in the Moreton region of South-East Queensland". Thesis, Queensland University of Technology, 1997.

Encontre o texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
27

Sampson, Shae-Lynn. "Response of wetlands to impacts from agricultural land-use practices: Implications for conservation, management, and rehabilitation in the Nuwejaars Catchment, Western Cape". University of the Western Cape, 2021. http://hdl.handle.net/11394/8154.

Texto completo da fonte
Resumo:
Magister Artium - MA
Wetlands occupy about 6% of the world’s surface and are fragile ecosystems that support a diversity of plants and animals. Wetlands are increasingly recognised for their role in the provision of ecosystem services and contribution to global biodiversity. Despite this, more than half of the world’s wetlands have vanished or been degraded, primarily due to agriculture. Wetlands are constantly adjusting to disturbances occurring within them and within their surrounding landscape. It is important to recognise to what extent various disturbances affect wetlands when assessing disturbance and impact, and when considering wetland protection options. The benefit of the detailed characterisation of the sub-catchments of the Nuwejaars catchment is deepened understanding of how different combinations of land-uses and soils impact catchment hydrology, and ultimately, the wetlands within the catchment
Estilos ABNT, Harvard, Vancouver, APA, etc.
28

Ntakumba, Stanley Sixolile. "The hydrogeomorphology of the Featherstone Kloof Catchment". Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1007862.

Texto completo da fonte
Resumo:
Wetlands are an important part of the landscape as hydrogeomorphological ecosystems. Over the centuries their importance has not received relevant attention; instead they have been treated as wastelands impeding development for maximum economic benefits. Research evidence from different parts of the world has influenced the change of such negative perceptions to an extent that the issue of wetlands' rehabilitation/restoration, conservation and management is firmly on the global agenda and local agendas of various countries, as evidenced by the adoption of the Ramsar Convention in 1971, and the Working for Water and Working for Wetlands programmes of the South African government. The aim of this research was to investigate the hydrological and geomorphological functions of a headwater wetland located in the Featherstone Kloof Catchment near Grahamstown, South Africa. The research was based on the hypotheses that wetlands store sediments, attenuate floods, store water and prolong downstream flows. A literature survey was conducted to gauge the state of knowledge about wetlands, particularly their hydrogeomorphology. An attempt was made to locate the study area within the broad historical and spatial context using a number of methods, including the radiocarbon dating of wetland sediments, the review of relevant literature and the analysis of historical hydroclimatic data. The results revealed that the wetland has existed for approximately 2000 years - as the oldest radiocarbon date obtained was 1850±50 BP. An analysis of more than a century (+120 years) long Grahamstown rainfall series indicated a steady fluctuation of rainfall around the mean, with regular decada1 cycles of wet and dry spells. Years with more rain below average were more common than those with higher rainfall, and storms events were quite common in the III area over the period. The distribution of seasons in the area over a calendar year period was demonstrated through the use of evaporation data. An intensive monitoring of hydrological and geomorphological variables was carried out using a combination of methods. The topography of the instrumented site was determined using a Total Station from reference benchmarks. Hydrological measurements included a nest of forty-eight piezometers for water table monitoring, and streamflow gauges at the upstream and downstream limits of the study site. Soil stratigraphic analysis was carried out through field techniques and laboratory measurements. A survey of wetland sediments was carried out after the main floods events. Data generated were used to analyse relationships between various variables and their role on the functioning of the wetland. The water balance of the wetland was quantified. The results indicated that the wetland was able to perform the cited hydrogeomorphological functions to some extent. For example, one of the key findings of this research is that the wetland was important in sustaining base flows under normal circumstances. However, the wetland did little to attenuate large floods. The results also revealed some important questions that require further research, including the role played by extreme flood events in altering wetland characteristics, the contribution of each water balance component in the hydrological functioning of wetlands, and importance of quantifying sediment budgets of headwater wetlands. The study demonstrated the complex nature of the wetland hydro geomorphology and that certain questions about wetlands require direct field monitoring to be better understood.
KMBT_363
Adobe Acrobat 9.54 Paper Capture Plug-in
Estilos ABNT, Harvard, Vancouver, APA, etc.
29

Fritz, Gisela B. "The floral and faunal recovery of a restored coastal wetland : Kunz Marsh, South Slough, Coos Bay, Or. /". Connect to title online (Scholars' Bank), 2001. http://hdl.handle.net/1794/5381.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
30

Chattaraj, Diyali. "Assessment of wetland resources in Malda district and its conservation for sustainable management". Thesis, University of North Bengal, 2019. http://ir.nbu.ac.in/handle/123456789/4033.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
31

Lee, Kai-tung, e 李啟同. "A review of freshwater wetland conservation in Hong Kong: policy and practice". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45013494.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
32

Chung, Hung-fat, e 鍾洪發. "An investigation of the role of Mai Po Nature Reserve from a conservation and education perspective". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31254536.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
33

Wong, Sui-kan, e 黃緖勤. "A critical review of wetland protection in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31255139.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
34

Yetman, Caroline Angela. "Conservation biology of the giant bullfrog, Pyxicephalus adspersus (Tschudi, 1838)". Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/31245.

Texto completo da fonte
Resumo:
The giant bullfrog, Pyxicephalus adspersus, is a large, explosive-breeding anuran from southern Africa, which spends most of the year buried in a state of torpor. In South Africa this species is considered to be Near-Threatened by habitat loss and other factors, especially in the densely human populated Gauteng Province. The aim of this thesis was to obtain essential outstanding information about the ecology of P. adspersus to contribute towards improved conservation management of this species. A model was used to predict the geographic range of P. adspersus in southern Africa, and recent land cover data were used to determine the amount of suitable habitat remaining for this species in Gauteng. As a step towards identifying P. adspersus conservation management units, genetic structure and gene flow for populations from 23 localities in Gauteng and seven additional localities in the north-eastern interior of South Africa was quantified using 708 base pairs of the mitochondrial gene cytochrome b. To investigate the unpredictable activity and unknown spatial habitat requirements of P. adspersus, a population’s spawning and non-breeding activity was monitored, and the movements of 70 adult frogs were radio- or spool-tracked during five summers at a site in Diepsloot, Gauteng. Using skeletohronology, the age distribution of breeding P. adspersus at this and two other peri-urban sites near Johannesburg, Gauteng, was examined. Bioclimatic conditions were predicted to be suitable for P. adspersus in the temperate to semi-arid interior, but not the low-lying eastern subtropical and arid western sides of southern Africa. Limited genetic data suggested that P. adspersus was common in the north-eastern interior of South Africa, and that populations in the Free State Province represent an evolutionary significant unit of this species. In central Gauteng, where P. adspersus may have declined by > 90%, populations < 20 km apart exhibited significant genetic differentiation, possibly as a result of genetic drift. At Diepsloot, both annual numbers of spawning events and numbers of spawning males were positively correlated with rainfall, although other meteorological variables also affected the activity of P. adspersus. Radio- or spool-tracked frogs showed high fidelity to their breeding site and burrows, which were situated up to 1 km away from the water. Male P. adspersus probably live 20 years in the wild, but at some peri-urban breeding sites adult life expectancy and body size may be declining. The geographic range of P. adspersus was predicted to be slightly smaller than that reported by other authors, and deserves phylogeographic validation. The main conservation priority for P. adspersus in South Africa should be the protection of terrestrial habitat for adult foraging and aestivation around, and for juvenile dispersal and gene flow between, breeding sites. In Gauteng, the conservation of a P. adspersus metapopulation is critical, and could most likely be achieved in the northern region of this province. Populations in the Free State Province deserve improved protection given their reported genetic uniqueness. At local spatial scales specific threats (e.g. pollution) should be ameliorated, and long-term monitoring should be implemented to detect real population trends.
Thesis (PhD)--University of Pretoria, 2012.
Zoology and Entomology
Unrestricted
Estilos ABNT, Harvard, Vancouver, APA, etc.
35

Almalki, Mohammed. "Conservation biology of wetland birds : breeding ecology, spatial analyses and genetic differentiation". Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665415.

Texto completo da fonte
Resumo:
Conservation biology uses various tools including spatial ecology and molecular ecology to provide better understanding of species that can be used to support and design effective conservation strategies. Many wetland bird species in the Kingdom of Saudi Arabia (KSA) are poorly known, and we lack detailed knowledge about their breeding ecology, spatial distribution and genetic differentiation. The first objective of my PhD research was to investigate the parental behaviour of an understudied endemic shorebird to the Middle East, the Crab Plover Dromas ardeola to record parental behaviour at the burrows over a 24-hour period. Since adult males and females look identical, I used molecular markers for sex determination. Molecular sexing was conducted using two different markers applied for 66 Crab Plover blood samples. I demonstrated that both males and females fed chicks, and that females brought food to chicks more frequently than did males (Chapter 2). The second objective was to investigate the breeding distribution of Crab Plovers along the Red Sea coast of Saudi Arabia and to compare the results with the last comprehensive survey conducted in 1996. I showed that the Red Sea coast of Saudi Arabia has approximately 35% of the Arabian breeding population of Crab Plovers. The major threats to this species along the Red Sea coast were also discussed (Chapter 3). The third objective was to model the spatial distribution of 22 wetland bird species along the Red Sea coast of Saudi Arabia using maximum entropy (MaxEnt) based on occurrence data and 10 environmental variables and then to determine sites with high species richness. This analysis identified 17 areas predicted to be suitable for supporting high species richness. I recommended using this model of areas with high wetland bird species richness as a guide for monitoring and surveys to inform conservation strategies in the Red Sea region of the KSA (Chapter 4). The fourth objective was to use microsatellite markers to investigate the genetics and morphometric differentiations of a wide-spread shorebird species, the Kentish Plover, between islands and mainland sites. The main result of the latter investigation was that breeding populations are genetically and morphometrically differentiated between mainland sites and islands, as well as between different archipelagos. This finding calls for a reconsideration of the current conservation status of this species (Chapter 5). Finally, my PhD research has generated several research lines that warrant further investigation (Chapter 6).
Estilos ABNT, Harvard, Vancouver, APA, etc.
36

Reisner, Gunilla. "Conflicting Environmental Management Tools : Grazing of Semi-natural Grasslands vs. Wetland Conservation". Thesis, Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-22674.

Texto completo da fonte
Resumo:
The study explores the possibility of conflicts between conservation of wetlands and semi-natural grasslands in the county of Stockholm. Both habitats are important to protect from a biodiversity perspective. The species rich semi-natural grasslands have been created by agricultural practices like grazing and mowing. At the same time, wetlands have diminished due to earlier drainage in order to increase the area of arable land. Both habitats are incorporated in the Swedish Environmental Objectives and are parts of the EU’s Agri-Environmental Schemes (AES), where farmers get financial support to maintain or restore valuable habitats. Wetland conservation/restoration often requires raised water tables, but also maintenance with cattle grazing in certain areas. On the other hand, raised water tables can act as hinder for grazing animals and lead to conflict situations. Using a mixed method approach, this study scrutinized if the use of different management tools can result in conflicts between actors and objectives. The study is based on a literature review, interviews and the use of Geographical Information Systems (GIS). Institutionalism and the Institutional Analysis and Development framework are used to analyze and evaluate the situation in the county of Stockholm. The quantitative results reveal that 12,8 % of all semi-natural grasslands of high biological value intersects with wetlands. However, these areas are maintained with environmental support to a larger extent than semi-natural grasslands outside wetlands. This indicates there is no conflict between wetland and semi-natural grassland conservation, a perception shared by authorities. From farmers’ perspective the situation is described differently, rule compliance for environmental support is hard to obtain specifically in wet areas. Increased dialogue between authorities and farmers rather than harsh inspections would be preferable as the county of Stockholm needs more farmers and grazing cattle to maintain biologically important habitats. Grazing in wetlands is needed from a biodiversity perspective but can at the same time disturb the wetlands functioning of nutrient reduction. There is a risk of authorities prioritizing water quality in front of biodiversity in conflicting situations. Water, as a common-pool recourse, is surrounded by stricter regulation and also easier to monitor.
Estilos ABNT, Harvard, Vancouver, APA, etc.
37

Carrillo-Guerrero, Yamilett Karina. "Water Conservation, Wetland Restoration and Agriculture in the Colorado River Delta, Mexico". Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/195396.

Texto completo da fonte
Resumo:
In arid lands, wetland loss is the result not only of the scarcity of water itself, but of the management of water to maximize off-stream uses. Declaring a wetland as a protected natural area is not enough when its water supply is not protected as well. In a fully-diverted, over-allocated, drought-prone Colorado River ecosystem, its delta has no instream flows allocated. Water use efficiency (WUE) is touted as the panacea for water shortages and lack of instream flows. I evaluated the relationships between water use in the Mexicali Irrigation District and the water supply for the Colorado River delta wetlands. The survey applied to 521 farmers complemented the GIS analysis to create a spatial distribution of agronomic and socio-economic factors influencing farmers’ options to improve WUE in irrigation. Mexicali farmers apply 10,496 m³/ha/yr; 4% higher than the legal allotment. Still, 28% of the district’s soils are salt-affected (ECe > 8dS/m), 19% are sodic (ESP > 50%), and 39% of the salt load in irrigation water accumulates in the soils. Thus, Mexicali farmers apply more water than plants need in order to maintain the sustainability of their soils. From an agronomic perspective, increasing WUE is feasible in 80% of the valley. However, high costs and lack of technical knowledge limit farmers’ options to either continue using as much water as they do now or rent/sell their water rights to larger farming operations or urban developments. Mexicali’s agriculture provides 87 Mm³ of water to the delta marshes, and seepage from unlined canals and subsurface flows generated by irrigation contribute to sustain riparian areas. Agricultural “inefficiencies” become the main source of water for wetlands when flows are fully diverted. The Irrigation District 014 is an integral part of the delta ecosystem; this is a required change in the agriculture-wetland paradigm. The restoration of arid and over-allocated rivers requires the integration of irrigation practices and WUE with the allocation of water for instream flows. The restoration of wetlands of international watersheds like the Colorado River requires the bi-national collaboration beyond memorandums of understanding between the countries; treaties where environmental flows are actually allocated will better serve shared ecosystems.
Estilos ABNT, Harvard, Vancouver, APA, etc.
38

Aliberti, Lubertazzi Maria Adella. "Natal habitat use by dragonflies along landscape gradients in Rhode Island /". View online ; access limited to URI, 2009. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3378088.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
39

Greer, Nan Marie. "Ethnoecology of taro farmers and their management of Hawaiian wetlands and endangered waterbirds in taro agroecosystems /". Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6443.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
40

Chan, Chung-san, e 陳仲新. "The future of the Deep Bay Wetlands, Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31253647.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
41

Leung, Wai-hung, e 梁偉雄. "The conservation of coastal wetlands, especially the Mai Po marshes, in Hong Kong: problems and prospects". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31253441.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
42

Lau, Lai-ki, e 劉麗琪. "Effectiveness of planning and management on Ramsar site in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31260287.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
43

Wan, Chi-lam Floyd, e 溫智霖. "Wetland and water ecology centre in Tai O". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45009715.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
44

Cowden, Craig. "Assessment of the long-term response to rehabilitation of two wetlands in KwaZulu-Natal, South Africa". Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/60606.

Texto completo da fonte
Resumo:
Assessing the outputs and outcomes of wetland rehabilitation activities is recognised by the 'Working for Wetlands' programme in South Africa as important, but to date has been limited. An assessment of the ecological outcomes and the structural outputs of the Working for Wetlands rehabilitation implemented in the Killarney and Kruisfontein wetlands, KwaZulu-Natal, in 2005 was undertaken. The assessment of outcomes included an evaluation of the changes in terms of ecological integrity and the supply of ecosystem services, using WET-Health and WET- EcoServices assessment techniques respectively, and vegetation composition. Improvements in hydrological and geomorphic integrity were recorded in both wetlands, resulting in improved ecosystem services delivery. However, investigation of vegetation composition using the Wetland Index Value and Floristic Quality Assessment Index showed that, seven years after rehabilitation, KiNamey's vegetation composition had improved, but Kruisfontein's vegetation was still largely dominated by pioneer species and appeared to be stable, but in a severely transformed state. The response of these wetlands has shown that sites for rehabilitation should be screened before work begins, and wetlands requiring intensive management of vegetation recovery should be assessed in terms of the objectives and the anticipated benefits of the project. The assessment of the outputs included an evaluation of structural integrity, survival and cost- effectiveness. Limited issues, mostly relating to deviations from the designs during construction, were identified with regards to the structural outputs at each of the wetlands. However, the spreader canals at both Killarney and Kruisfontein wetlands were not functioning as intended and concentrated flows from the spreader canals were evident in both wetlands. The use of spreader canals should therefore be carefully planned and implemented for future wetland rehabilitation projects. Consideration of ZAR per hectare equivalent re-instated/secured provided a useful initial means of determining the cost-effectiveness of the wetland rehabilitation. However, additional factors need to be considered, such as, the nature of the rehabilitation activities, the type and size of the problem being addressed, rehabilitation of priority wetlands, limitations imposed by funders, and risks that need to be addressed by the rehabilitation strategy. Furthermore, the evaluation of the Killarney and Kruisfontein wetlands highlighted the need to revise the Water Research Commission's Wetland Management Series, especially those documents or guidelines relating to rehabilitation planning (WET-RehabPlan), interventions (WET-RehabMethods), and monitoring and evaluation (WET-RehabEvaluate).
Estilos ABNT, Harvard, Vancouver, APA, etc.
45

Chu, Wing-hing. "Conservation of terrestrial biodiversity in Hong Kong /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19737439.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
46

Daniels, Neil. "A systematic conservation plan for threatened freshwater wetlanddependent waterbirds across South Africa". University of Western Cape, 2020. http://hdl.handle.net/11394/8000.

Texto completo da fonte
Resumo:
Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol)
Freshwater ecosystems are valuable to all components of biodiversity communities. Globally, these ecosystems are threatened by human activity and as a consequence, many vertebrates, including waterbirds, have become threatened. Wetlands are one of the most productive ecosystem types in the world. Yet, despite this, many protected area networks around the world fail to include this ecosystem type in their protected area networks. On a national scale, in South Africa, wetland loss and deteriorating wetland habitat quality continues to restrict and reduce the range of wetland waterbirds. For this thesis, Maximum Entropy (MaxEnt) species distribution modelling was used to identify additional areas of possible waterbird occurrence. The MaxEnt results noted that waterbirds rely on a combination of these environmental variables for their distribution ecology in their wetland habitat, with vegetation and humidity variables having the highest predictive powers. These would be considered important predictor variables for the distribution ecology of these waterbirds.
Estilos ABNT, Harvard, Vancouver, APA, etc.
47

Fitzgerald, Megan. "The relationship between biodiversity and ecosystem function in a coastal wetland". Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1572435.

Texto completo da fonte
Resumo:

Despite reductions in species diversity, few studies in wetlands investigate the relationship between biodiversity and ecosystem function (BEF). My research explores the BEF relationship in a recently restored salt marsh in Long Beach, California. I hypothesized that: (1) increasing plant diversity would result in higher primary productivity and decreased recruitment of native salt marsh plants, (2) observed variation in responses would be correlated with species-specific variation in individual demographic parameters, and (3) variation in demographic parameters and resulting ecosystem processes would be correlated with functional traits. I found that while survival over one year was correlated with elevation, overall percent cover and recruit species richness were positively affected by diversity. Performance patterns reveal variation by species in photosynthetic rate, leaf mass per area and chlorophyll a/b ratios. After one year, I found that the overall diversity patterns were driven by selection effect compared to complementarity.

Estilos ABNT, Harvard, Vancouver, APA, etc.
48

Long, Peter. "Ecological and life-history basis of wetland bird conservation : phylogenetic and spatial analyses". Thesis, University of Bath, 2008. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.512313.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
49

Herman, Brook Danielle. "Testing the Floristic Quality Assessment Index in natural and created wetlands in Mississippi, USA". Master's thesis, Mississippi State : Mississippi State University, 2005. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
50

Perry, Kenneth William. "The ecology and conservation of great crested grebes Podiceps cristatus at Lough Neagh, Northern Ireland". Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326328.

Texto completo da fonte
Estilos ABNT, Harvard, Vancouver, APA, etc.
Oferecemos descontos em todos os planos premium para autores cujas obras estão incluídas em seleções literárias temáticas. Contate-nos para obter um código promocional único!

Vá para a bibliografia