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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.
1

THE EFFECTS OF WILLOW SHRUB ENCROACHMENT ON SOIL ORGANIC CARBON STORAGE IN A SOUTH FLORIDA HERBACEOUS WETLAND

Unknown Date (has links)
Storing almost a third of the global soil carbon pool, wetlands are an essential component of the carbon cycle, and carbon-rich peat soil accumulates when carbon input through primary productivity exceeds output through decomposition. However, woody shrub encroachment in herbaceous wetlands can alter soil carbon processes, potentially diminishing stored carbon. To examine the effects of shrub encroachment on soil carbon, I compared soil carbon input through litterfall and fine root production, output through decomposition, and below-canopy microclimate conditions between Carolina willow shrub (Salix caroliniana) and herbaceous sawgrass (Cladium jamaicense) in the Blue Cypress Marsh Conservation Area (BCMCA), FL. To assess the level of production and its response to water level, I compared aboveground green biomass by measuring normalized difference vegetation index (NDVI) and photosynthetic stress by measuring photochemical reflectance index (PRI) between sawgrass and willow. I collected willow litterfall using litter traps and measured sawgrass and willow fine root production with fine root ingrowth bags. Litter decomposition was measured with decomposition bags deployed using a reciprocal litter placement design at BCMCA and incubated in a greenhouse to examine the effects of char and water level on decomposition. Above and belowground microclimate conditions were measured using sensors installed within sawgrass and willow canopies. Despite experiencing more photosynthetic stress, willow produced more green biomass than sawgrass. However, willow produced fewer fine roots than sawgrass and these roots were deeper within the soil. Willow litter decomposed faster even though sawgrass decomposition increased under drier conditions. Compared to the sawgrass canopy, the willow canopy had greater light availability, lower evaporative demand plus warmer and drier soils; however, litter decomposition did not differ between the canopies. These results suggest that willow encroachment can reduce the amount and alter the distribution of carbon within an herbaceous wetland, likely resulting in a net loss of soil carbon. Although willow encroachment may increase aboveground biomass carbon stocks, these stocks will likely be offset by a loss of soil carbon due to reduced fine root production and increased decomposition. Therefore, the transition from herbaceous wetland to shrub wetland will likely result in a loss of stored soil carbon. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
2

Effects of cooperative governance in the sewage treatment works in the upper Vaal River / M.F. Mamabolo.

Mamabolo, Mmamala Florah January 2012 (has links)
The Upper Vaal Water Management Area (Upper Vaal WMA) lies in the eastern interior of South Africa. This WMA includes the Vaal, Klip, Wilge, Liebenbergsvlei and Mooi Rivers and extends to the confluence of the Mooi and Vaal Rivers. It also includes major dams such as the Vaal Dam, Grootdraai Dam and Sterkfontein Dam. The southern half of the WMA extends over the Free State province; the north-east mainly falls within Mpumalanga and the northern and western parts in Gauteng and North West provinces respectively (DWAF 2004). Several wastewater treatment works (WWTW) located in this area do not meet the standard set by the present legislation that addresses proper treatment of water. This results in number of problems that affect the quality of water in this catchment. It was noted by the WRC (2006b) that with the challenges of implementation in an environment of shared responsibility, it is increasingly recognised that public/government institutions must foster institutional cooperation and interaction for efficient provision of public services, both at the policy-strategy level and the operational-implementation level. According to WRC (2006b), poor cooperation between institutions in the implementation of their interrelated mandates has resulted in inefficient utilization of scarce resources and/or endless disputes. In order to address this shortcoming, a study that investigated the effects of cooperative governance in the Wastewater Treatment Works (WWTW) in the Upper Vaal Water Management Area was initiated. The results of the research indicate a lack of cooperation between the three spheres of governance that participate in the sustainable management of water treatment in this area. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2013.
3

Effects of cooperative governance in the sewage treatment works in the upper Vaal River / M.F. Mamabolo.

Mamabolo, Mmamala Florah January 2012 (has links)
The Upper Vaal Water Management Area (Upper Vaal WMA) lies in the eastern interior of South Africa. This WMA includes the Vaal, Klip, Wilge, Liebenbergsvlei and Mooi Rivers and extends to the confluence of the Mooi and Vaal Rivers. It also includes major dams such as the Vaal Dam, Grootdraai Dam and Sterkfontein Dam. The southern half of the WMA extends over the Free State province; the north-east mainly falls within Mpumalanga and the northern and western parts in Gauteng and North West provinces respectively (DWAF 2004). Several wastewater treatment works (WWTW) located in this area do not meet the standard set by the present legislation that addresses proper treatment of water. This results in number of problems that affect the quality of water in this catchment. It was noted by the WRC (2006b) that with the challenges of implementation in an environment of shared responsibility, it is increasingly recognised that public/government institutions must foster institutional cooperation and interaction for efficient provision of public services, both at the policy-strategy level and the operational-implementation level. According to WRC (2006b), poor cooperation between institutions in the implementation of their interrelated mandates has resulted in inefficient utilization of scarce resources and/or endless disputes. In order to address this shortcoming, a study that investigated the effects of cooperative governance in the Wastewater Treatment Works (WWTW) in the Upper Vaal Water Management Area was initiated. The results of the research indicate a lack of cooperation between the three spheres of governance that participate in the sustainable management of water treatment in this area. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2013.
4

A political policy analysis of the integrated water resource management approach in South Africa’s water policy (1998 – 2001)

Mulder, Marthinus Wessel 12 September 2005 (has links)
The aim of the study emanates from the research question: Is the incorporation of the integrated water resource management (IWRM) approach in South Africa’s water policy, from a political point of view, appropriate? The IWRM approach, as applied to developing countries, originated in developed countries with predominantly homogeneous societies where there is a broad commitment to democratic principles, the free market system and individualism. Societies in developing countries do not necessarily share the same characteristics associated with those in developed countries. South Africa, classified as a developing country, has a multicultural society that reflects an income disparity and two major cultures, namely a modernised Western and a traditional African culture. As a result two subsidiary research questions follow: Can the commitment and impartiality of all the stakeholders that partake in the decision-making processes of water institutions at all levels be ensured? Is it possible to establish small, efficient and financially viable bureaucratic structures (water institutions) at the level of water management areas (WMA)? The study uses the public choice theory to assess the IWRM approach in selected developed and developing countries. The applicability of public choice concepts with reference to the differences between Western and African cultures are briefly alluded to. It also defines the IWRM approach and certain IWRM elements that have political implications for society at large. The study describes specific elements of the IWRM approach in France and Australia and the relative successes thereof in terms of the public choice theory. The implementation of the IWRM approach in Indochina and selective developing countries in Sub-Saharan Africa are described to highlight certain institutional problems, inadequate financial resources, the lack of capacity and various cultural aspects that inhibit the efficiency and effectiveness of the IWRM approach. In the analysis of South Africa’s water policy, the study found that the multicultural nature of society, the unequal levels of economic development and the limited level of technological and scientific knowledge, will make it extremely difficult to implement the IWRM approach without contextualising it. According to the public choice theory, the net benefits of a policy for a society must outweigh the costs. If not, the policy needs to be either adjusted or abandoned. Since none of the proposed catchment management agencies (CMA) were established between 1998 and 2001, it is not possible to come to a verifiable conclusion. However, the study indicates that the opportunity costs of the IWRM approach are likely to outweigh the benefits for society. Other aspects that necessitate a re-evaluation of South Africa’s water policy are the holistic element of the IWRM approach and the demarcation of WMAs. The study identifies three options: The first option is to revert back to the riparian principle. The second option is to either revisit the concept of public participation, or to re-delineate the WMAs. The third and most favourable option is to abandon the concept of public participation. It would not only negate the need for CMAs (and indirectly WMAs), but would also greatly simplify the management of water resources. / Dissertation (M (Political and Policy Studies))--University of Pretoria, 2006. / Political Sciences / unrestricted
5

Responding to water demand strategies : case study in the Lower Orange catchment management area (LOCMA) / C.M. Gouws.

Gouws, Catharina Maria January 2010 (has links)
This study is an investigation into water management policies in South Africa, their effect on water users and the perceptions users have of these policies. The investigation begins with an exposition of concepts such as water demand management (WDM), as well as integrated water resource management (IWRM). A sub-discourse of the main theme is the societal tendency to neglect its common property. Garret Hardin's groundbreaking observations on the "tragedy of the commons" (1968) are explored in an effort to locate issues of relevance in effective water management strategies. In contemplating the commons, it is evident that aspects of morality and ethics are involved. The morality of a society be it in a global or national context, seems to manifest itself in legislation and policies, and in the way these are implemented. The relevance of good governance, hydropolitics and sustainable development is also discussed to provide the necessary theoretical background to an understanding of the relationship between consumers and the water commons. Access to safe drinking water is protected in the Constitution of the Republic of South Africa Act, 108 of 1996. Flowing from the government's obligation to take reasonable legislative and other measures to achieve the progressive realisation of fundamental human rights stipulated in section 27(2) of the Constitution, the challenge since 1994 has been to provide access to water for all inhabitants and to manage the available water resources effectively. Furthermore, the objective of subsequent water legislation such as the National Water Act, 36 of 1998 and regulatory plans, like the National Water Resource Strategy has been to incorporate international trends in water governance. The Department of Water and Environmental Affairs (DWEA) divided South Africa into 19 regions, called water management areas (WMA). In this study, attention is focused on what constitutes a catchment and how a catchment management agency (CMA) governs its water resources. A description is provided of the functions of water user associations (WUAs) and how ththe Lower Orange Catchment Management Area is, for example, the blueprint from which stakeholders develop their goals. In this study, the water situation in the Lower Orange Water Management Area is under scrutiny. The focus is on the three main institutional components of water management (the Lower Orange catchment management, the Upington Islands Water User Association [UIWUA] and the //Khara Hais Local Municipality). The progress of the establishment of the Lower Orange Catchment Management Agency is outlined over a period of five years. Meanwhile, the Upington Islands Water User Association was developed and this has grown in stature. The work being done by these institutions is investigated by looking at grassroots effects, especially in respect of irrigation activities. The unique water management circumstances of the //Khara Hais Local Municipality are then investigated along with the plans outlined in their Integrated Development Plan {lOP) and their Water Services Development Plane Internal Strategic Perspective (ISP) of(WSDP). Because local irrigation operations consume most of the available surface water in the Lower Orange Water Management Area, irrigation farmers and their activities warrant closer attention. A historical overview is given of the development of irrigation in the region followed by an assessment of the role of two of the most prominent historical figures in Upington, Reverend Adriaan Schroder and Abraham "Holbors" September. Ultimately, however, the focus falls on the current state of irrigation in the area. It is possible to distinguish between the approach of large commercial farming operations and that of smaller irrigation farming units to irrigation. Specific attention is given to the perceptions of irrigation farmers as far as the policies and legislation pertaining to water issues is concerned. This study will hopefully provide the Department of Water and Environmental Affairs(DWEA), //Khara Hais Local Municipality and organised agriculture with some recommendations on efficient integrated water management strategies. It might well be of value to other municipalities who are experiencing similar problems. The aim has been to identify typical problems and potential disputes between water management institutions and relevant role-players. / Thesis (Ph.D. (Public Management and Administration))--North-West University, Vaal Triangle Campus, 2010.
6

Responding to water demand strategies : case study in the Lower Orange catchment management area (LOCMA) / C.M. Gouws.

Gouws, Catharina Maria January 2010 (has links)
This study is an investigation into water management policies in South Africa, their effect on water users and the perceptions users have of these policies. The investigation begins with an exposition of concepts such as water demand management (WDM), as well as integrated water resource management (IWRM). A sub-discourse of the main theme is the societal tendency to neglect its common property. Garret Hardin's groundbreaking observations on the "tragedy of the commons" (1968) are explored in an effort to locate issues of relevance in effective water management strategies. In contemplating the commons, it is evident that aspects of morality and ethics are involved. The morality of a society be it in a global or national context, seems to manifest itself in legislation and policies, and in the way these are implemented. The relevance of good governance, hydropolitics and sustainable development is also discussed to provide the necessary theoretical background to an understanding of the relationship between consumers and the water commons. Access to safe drinking water is protected in the Constitution of the Republic of South Africa Act, 108 of 1996. Flowing from the government's obligation to take reasonable legislative and other measures to achieve the progressive realisation of fundamental human rights stipulated in section 27(2) of the Constitution, the challenge since 1994 has been to provide access to water for all inhabitants and to manage the available water resources effectively. Furthermore, the objective of subsequent water legislation such as the National Water Act, 36 of 1998 and regulatory plans, like the National Water Resource Strategy has been to incorporate international trends in water governance. The Department of Water and Environmental Affairs (DWEA) divided South Africa into 19 regions, called water management areas (WMA). In this study, attention is focused on what constitutes a catchment and how a catchment management agency (CMA) governs its water resources. A description is provided of the functions of water user associations (WUAs) and how ththe Lower Orange Catchment Management Area is, for example, the blueprint from which stakeholders develop their goals. In this study, the water situation in the Lower Orange Water Management Area is under scrutiny. The focus is on the three main institutional components of water management (the Lower Orange catchment management, the Upington Islands Water User Association [UIWUA] and the //Khara Hais Local Municipality). The progress of the establishment of the Lower Orange Catchment Management Agency is outlined over a period of five years. Meanwhile, the Upington Islands Water User Association was developed and this has grown in stature. The work being done by these institutions is investigated by looking at grassroots effects, especially in respect of irrigation activities. The unique water management circumstances of the //Khara Hais Local Municipality are then investigated along with the plans outlined in their Integrated Development Plan {lOP) and their Water Services Development Plane Internal Strategic Perspective (ISP) of(WSDP). Because local irrigation operations consume most of the available surface water in the Lower Orange Water Management Area, irrigation farmers and their activities warrant closer attention. A historical overview is given of the development of irrigation in the region followed by an assessment of the role of two of the most prominent historical figures in Upington, Reverend Adriaan Schroder and Abraham "Holbors" September. Ultimately, however, the focus falls on the current state of irrigation in the area. It is possible to distinguish between the approach of large commercial farming operations and that of smaller irrigation farming units to irrigation. Specific attention is given to the perceptions of irrigation farmers as far as the policies and legislation pertaining to water issues is concerned. This study will hopefully provide the Department of Water and Environmental Affairs(DWEA), //Khara Hais Local Municipality and organised agriculture with some recommendations on efficient integrated water management strategies. It might well be of value to other municipalities who are experiencing similar problems. The aim has been to identify typical problems and potential disputes between water management institutions and relevant role-players. / Thesis (Ph.D. (Public Management and Administration))--North-West University, Vaal Triangle Campus, 2010.

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