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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.
71

Characterising the role of climate change in perpetuating Zimbabwean farmers' health risks from exposure to endocrine disrupting pesticides

Zinyemba, Cliff 06 November 2020 (has links)
Climate change and endocrine disrupting chemicals are currently amongst key drivers for a range of non-communicable diseases and adverse human health conditions. Pesticides constitute an important source of endocrine disrupting chemicals. A growing public health concern is the potential relationship between climate change and adaptive increases in agricultural pesticide use. Effectively, with increases in pesticide use, there may be increased potential for elevated pesticide exposures and, thus, increased endocrine disrupting health risks. The aim of this thesis was to assess whether climate change is a key risk perpetuating factor for endocrine disrupting health risks due to increased agricultural pesticide uses and exposures. The study was conducted in Zimbabwe with farmers in the cotton farming district of Rushinga. Three research methods: 1) interviews with farmers, 2) quantitative structure-activity relationship modelling and, 3) stakeholder interviews with government cotton agronomists working in Rushinga district who acted as key informants. Qualitative in-depth interviews were conducted with 50 active smallholder farmers who had grown cotton for a minimum of 30 years. The interviews gathered farmers' perceptions and observations regarding climate change, changes in pest types, pest populations, pesticide use patterns, pesticide handling practices, and adaptive practices, amongst others. Quantitative structure-activity relationship modelling was, further, applied in identifying key risk pesticides of concern. Amitraz, endosulfan, fenvalerate and lambda-cyhalothrin were determined as having a high likelihood of acting as endocrine disruptors, as validated by literature highlighting the four pesticides' hormone-related cognitive, physiological and reproductive adverse health effects. Findings indicated that a number of farmers' adaptative practices were found to be incremental and, potentially, maladaptive, thereby enhancing pesticide use and exposure. This was indicative of climate change's potential for perpetuating pesticide-related endocrine disrupting health risks. Opportunities exist, however, for farmers to reduce pesticide use, and, thus, potential endocrine disrupting health risks through certain autonomous transformational adaptive practices, such as crop switching and cotton acreage reduction. Assistance to farmers by the government and development agencies, for enhancing opportunities for transformational adaptation is therefore recommended. Furthermore, there is need, at policy level, for phasing out pesticides with endocrine disrupting properties. There is, furthermore, a clear need for enhancing farmers' access to, and comprehension of, pesticide risk information through various innovative means, including research translation to reduce exposure risks.
72

Loss and damage from droughts: material and non-material impacts of water scarcity on women farmers in Gugulethu, Cape Town

Lavirotte, Lucy 16 March 2020 (has links)
Climate change is causing loss and damage (L&D) to those who are unable to adapt to its impacts. Coming from a growing recognition that adaptation to climate change has limits, the concept of L&D is a relative new-comer to the international agenda on climate change. To reduce L&D and compensate for it, the United Nations Framework on Climate Change (UNFCCC) first needs to understand what these residual impacts of climate change are. However, the literature on lived-experiences of L&D is limited, especially on non-material L&D which is more difficult to measure. Using Warner et al. (2013) definition of L&D, this study first assesses what material and non-material losses and damages from the Cape Town drought have been on a group of urban-poor women farmers. Then, this research uses a barriers and enablers to adaptation framework to understand how to reduce these losses and damages. This qualitative case-study investigates women farmers’ lived-experiences of L&D during the 2015-2017 drought in Gugulethu, a low-income settlement in Cape Town, to feed into broader debates on ways to reduce L&D in global south cities. Semi-structured interviews were conducted with six women farmers from the Umthunzi Farming Community and five other actors involved in urban agriculture in Gugulethu. The findings suggest that women farmers in this context are already experiencing L&D, with psychological, physical and social implications which appear to be particularly pertinent to their group. All participants had to reduce or stop farming which led to L&D on their urban agriculture benefits as well as L&D on their institutional trust towards the City of Cape Town. Most of these L&D were non-material. Some of the barriers to adapt and reduce L&D were a lack of external support (from the city and NGOs), a lack of financial capacity to adopt coping measures and a lack of knowledge on the possible coping measures and external support options. Enablers to reduce L&D from the drought were access to support from the Western Cape Department of Agriculture (DoA), higher levels of education, a diversity of livelihoods and a strong network with other farmers. In conclusion it emerged that external support from government departments and NGOs to urban-poor women farmers is important for adapting to the possibility of future droughts. The vulnerability of these women farmers in low-income areas need to be addressed at their roots. These emerging conceptual openings emphasise the importance of exploring lived-experiences of L&D to better reduce the risk of L&D in vulnerable communities. Further research is necessary on compensation for unavoidable L&D, which is beyond the limits of this research.
73

Barriers and enablers to the adoption of practices to improve crop production and reduce vulnerability to climate risks in the semi-arid Omusati Region,Namibia

Chappel, Angela 11 February 2019 (has links)
Namibia is almost entirely semi-arid or arid. With evaporation rates being higher than precipitation rates, farming conditions are extremely adverse. This is exacerbated by the impacts of climate change, namely increased temperature, decreased rainfall and higher rainfall variability, all of which are projected to worsen in the future. More than half of the population is reliant on rain-fed subsistence agriculture for their source of food but these challenging conditions mean that there is widespread food insecurity across the subsistence farming community in Namibia. This leads to a state of vulnerability and dependence on government support in the form of social grants, food aid and remittances from family members in urban areas. The locus for this study is three villages: Omaenene, Okathitukeengombe and Oshihau, in the north-central Omusati region of Namibia. This research investigated local perceptions of climate change vulnerability, farming practices used in other regions that could reduce this vulnerability and finally barriers and enablers to the uptake of new farming practices. These objectives were answered through the use of a systematic literature review and interviews with the local community. Findings revealed that the local population is already experiencing a hotter and drier climate, which has decreased their yield output. Many farmers are concerned about future climatic changes while some are comforted by support from the government or God. In both of these cases, the farmers are vulnerable because they are not currently adapting or planning to adapt to climate change. Although a majority of the farmers claimed that they are willing to try new farming practices, they are inhibited by: limited access to new information, mistrust of new farming practices as well as insufficient labour and resources. Three adaptive farming practices – planting pits, bunds and composting – aimed predominantly at water harvesting, soil conservation and increasing soil quality were selected by the researcher, from a systematic literature review, as appropriate for the village sites. Some of the social and institutional enablers that could be enhanced to promote the uptake of these practices are: i) support from local authorities and possibly enlisting the help of religious and traditional leaders (including building trust within these networks), ii) enhancing information access predominantly through the radio, iii) explaining the severity of climate change and the value of adaptation practices, iv) establishing self-help labour groups and v) the creation of demonstrations sites. In the face of irreversible climate change, this research aims to contribute to empowering local people to adapt their farming practices to the harmful experienced and predicted impacts of climate change and climate variability.
74

Challenges facing physical science educators in the implementation of the National Curriculum statement: the case of the Empangeni Education District

Mchunu, Stephan Paraffin January 2009 (has links)
A dissertation submitted to the Faculty of Education in partial fulfilment of the requirements for the Masters of Education in the Department of Mathematics, Science and Technology Education at the University of Zululand, South Africa, 2009. / This study looked at the implementation of the NCS physical science as a major curriculum change. As Imenda (2002:4) states "curriculum change entails that educators, learners, administrators, and all those with a part to play in the actualisation of the new curriculum have to see and do things differently". He further asserts that "this invariably means embracing a new system of doing things in terms of a sound philosophical basis, curriculum content description, beliefs, values, convictions and practices". He further posits that "the transition from an 'old' curriculum to a new one could therefore present difficult challenges and problems". According to Imenda (2002:4), "the espousal of OBE by South Africa's Ministry of Education to apply to all levels of the education system has presented a number of major challenges". Indeed, there are many challenges facing physical science educators in the implementation of OBE, including overcrowding, language mismatching, teacher unpreparedness, non-delivery of OBE resources, inadequate facilities and resources (Adler & Reed, 2002:60-65; Jacobs, Gawe & Vakalisa, 2002:106-107 & De Waal, 2004:63-66). In particular, student assessment is an integral part of the outcome-based approach to curriculum design and implementation. Accordingly, the implementation of valid and reliab!e assessment procedures is a centre piece 1 of outcomes-based education (OBE). The paradigm shift from the traditional curriculum to an OBE curriculum requires changes to be reflected in assessment practices. Thus, unless assessment is properly aligned with the curriculum reform and teaching, the desired changes in education will be extremely difficult, if not impossible, to realise. The current reform initiative in science education emphasizes the importance of teaching learners to be critical thinkers and problem solvers. Assessing whether learners understand basic science concepts and can use them to solve problems requires an approach very different from traditional tests that primarily measure the recall of isolated facts. As Rasool (1999: 177) points out: The traditional educational paradigm prevalent in schools is characterized by a heavily content-driven, teacher centered approach. Subjects are broken down in terms of rigidly defined syllabuses and tend to be knowledge focused rather than performance focused. While methodologies vary, the role of the teacher as a subject matter expert is largely that of provider of content. The following points are noted from the traditional curriculum: • Learners are often passive recipients of knowledge. • Emphasis is on memory, practice and rote learning. • Promotion of learners is based mainly on pencil and paper examinations. • Little or no emphasis is on creativity and the curriculum is overloaded with content; no attention is given to skill. • No emphasis on co-operative learning and discovery learning. • Competencies, knowledge and skills are not improved. 2 • Skills acquired outside school are regarded as inferior and largely not recognized (Department of Education, 1997: 27). In the new curriculum, the full scientific power of pupils is assessed. Students' performance is compared with established criteria"; students are viewed as active participants in the assessment process; assessment is regarded as continual and recursive. Overall, outcome-based assessment focuses on work done, assesses understanding and is motivational in nature (Lorraine, 1998: 58).
75

Climate change projections for Central America: A regional climate model study

Karmalkar, Ambarish 01 January 2010 (has links)
Central America has been identified as one of the regions in the world where potential climate change impacts on the environment can be pronounced and is considered a climate change ‘hot-spot’. The Intergovernmental Panel on Climate Change Fourth Assessment Report indicates that the region around the western Caribbean and Central America is one where a majority of the climate model simulations indicate rather large changes in temperature and precipitation. This region, however, is one with considerable topographic relief, which implies the existence of large gradients in many critical climate variables. The interactions between the complex topography of Central America and the neighboring oceans give rise to numerous climate zones, horizontally and vertically. Consequently, the region has high biodiversity, it harbors high-value ecosystems and it is important to provide more realistic scenarios to assist in adaptation and mitigation work in the region. In this study, I aim to understand climate change in Central America at spatial scales relevant for impacts assessment. A regional climate model PRECIS was employed to carry out two experiments: the baseline (present-day) run and the scenario run, both performed at 25-km horizontal resolution. The thorough examination of the model performance showed model’s success in capturing the spatial and temporal variability of the key climate variables and its strength in simulating topographically-induced regional climate features. The projected increase in temperature, a large decrease in precipitation in most of Central America, and corresponding hydrological changes under the A2 scenario may have serious negative consequences on water resources, agricultural activities and the ecosystem dynamics in the region.
76

An Assessment of the Gain from Using a Change-Point Analysis

Luong, The Minh 07 1900 (has links)
1 volume
77

Anatomy of a radical change

Nguyễn, Huy Quý. January 1998 (has links)
No description available.
78

Urbanization impacts on vegetation, heat, and water for improved climate adaptation

Smith, Ian Andrew 13 August 2024 (has links)
Urban ecosystems play a central role in global and regional climates by disrupting the surface energy balance and modifying nutrient and water cycling. Cities recognize the need for urban design strategies that address urbanization-induced climate stress but are limited by a lack of ecological knowledge to guide best practices in urban planning and design for climate adaptation. This dissertation combines remote sensing, field data collection, stable isotope analysis, and ecosystem modeling techniques to advance our understanding of core processes related to vegetation, heat, and water within urban climate systems. Combining and adapting models of photosynthesis, stomatal conductance, and evapotranspiration, we produce and validate fine spatiotemporal resolution estimates of latent heat flux from urban vegetation that account for unique urban climatological and physiological processes. The innovative modeling framework captures spatial heterogeneity in cooling benefits across the complex landscape of cities at a scale useful for informing policies aimed at mitigating urban heat exposure. We assess the effectiveness of urban greening and albedo manipulation to reduce surface temperatures across climate types in a spatial regression modeling framework. We find significant variability in the surface cooling efficiency of different vegetation forms, with tree cover cooling impacts approximately four times as strong as grass cover cooling impacts. Our results identify surface moisture as a powerful control on vegetation cooling efficiency, highlighting the role of background climate in selecting climate adaptation strategies. Using observed relationships between tree cover, albedo, and surface temperature, we demonstrate the importance of urban land cover composition in guiding effective climate adaptation strategies. Residential regions that are most vulnerable to extreme heat in Boston, Massachusetts are characterized by low canopy cover, few opportunities for tree planting, and a large proportion of flat, dark roofs, making white roof programs a promising strategy for reducing heat exposure disparities. In a field study of unirrigated street trees, we identify precipitation as the primary water source for trees confined to tree pits in a mesic city, supporting the storm water mitigation function of urban vegetation. However, the high proportion of water utilized from precipitation demonstrates the potential vulnerability of street trees to drought stress and points to water supplementation during dry periods as a possible key improvement in urban greening initiative implementation. Altogether, the results presented in this dissertation provide novel information to guide improved urban sustainability, resilience, and equity in a changing climate.
79

The small market town in the large multi-township parish : Shifnal, Wellington, Wem and Whitchurch c.1535-c.1660

Watts, Sylvia January 1995 (has links)
No description available.
80

Minimizing conflict implementing change in an established church /

Axtell, Douglas W. January 2008 (has links)
Thesis (D. Min.)--Bethel Theological Seminary, St. Paul, MN, 2008. / Abstract. Includes bibliographical references (leaves 159-163).

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