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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.
211

Ecological understandings of Indigenous landscape management shape the study of Pacific yew (Taxus brevifolia)

Reynolds, Geneviève 02 September 2022 (has links)
Indigenous landscape management has transformed ecosystems for millennia, with long-lasting impacts on the productivity and abundance of plant species. While western science based ecological research is beginning to investigate these impacts, less abundant species of cultural importance remain understudied. Pacific yew (Taxus brevifolia Nutt.), an uncommon understory conifer found in old-growth forests of the Northwest Coast of North America, has not received sustained ecological interest despite its importance to Indigenous Peoples throughout its range. In the first chapter, I synthesize the current ethnobotanical and ecological literature discussing Pacific yew to identify knowledge gaps and dominant paradigms that have shaped the study of the species. I find that many mechanisms behind Pacific yew’s habitat selection and ecosystem functions are unknown to western science and that the impacts of Indigenous landscape management are largely unacknowledged within the western scientific literature. In the following chapter, in partnership with the Heiltsuk First Nation, I examine the growth and abundance of Pacific yew on sites that were inhabited intensively by First Nations on the Central Coast of British Columbia for over 10,000 years. I find that habitation histories are not a strong driver of patterns of tree size and that Pacific yew abundance is largely driven by site aspect. These findings shed light on the habitat preferences of Pacific yew, which have rarely been studied in this region. They also illustrate variation in the response of culturally important species to landscape modification and highlight the need for nuanced understanding of the diversity of plant management strategies employed by Indigenous Peoples. This work is part of a broader attempt to incorporate cultural histories and questions into ecological study and to recognize the continuing ecological influences of Indigenous Peoples, who have stewarded their homelands for millennia. / Graduate
212

Ethnobotanical survey of medicinal plants with antifungal activities in Makhado Local Municipality, Limpopo Province, South Africa

Machaba, Tambudzani Caroline January 2018 (has links)
Thesis (M. Sc. (Botany)) -- University of Limpopo, 2018 / The aim of the study was to investigate medicinal plants used for the treatment of various ailments by the traditional healers and local people and to determine antifungal activities against animal fungal pathogens. Ethnobotanical survey was conducted to identify medicinal plants used by local people and traditional healers to treat various ailments in Makhado Local Municipality, Vhembe District, Limpopo, South Africa. A questionnaire was designed to gather information on the local name of plants, plant parts used and the methods of preparation and administration by the traditional healers. In our findings, sixty-three medicinal plants belonging to thirty-three families were identified to be used for treatment of various diseases such as chest complaint, sexual transmitted infections, headache, swollen legs, hypertension, blood purification, asthma, and infertility. Specific parts of the plant used for medicinal purposes vary from species to species and from one traditional healer to another. The dominant families were Fabaceae, Celastraceae and Euphorbiaceae. Of the sixty-three plants species identified, trees were the most predominant plant form (53%), followed by shrubs (23%), herbs (14%), and climbers (10%). Root, fruit, bark, leaves, seeds and in some instances the whole plant are used for the preparation of medicine while decoction and infusion were the general methods of preparation. The mode of administration of medicine was mainly oral. The most frequently used plant species were Warbugia salutaris (Bertol.f.) Chiov, Sclerocarya birrea (A.Rich) Hochst and Eleondron transvaalense (Burtt Davy) R.H. Archer. Eight plant species (Asparagus buchananii Bak., Albuca seineri (Engl. & K.Krause) J.C Manning & Goldblatt, Elephantorrhiza elephantina (Burch.) Skeels, Indigofera circinnata Benth, Maerua juncea Pax, Pentarrhinum insipidum E. Mey., Senna italica Mill. and Schinus molle L.) were selected based on the information given by the local people and the traditional healers for further phytochemical analysis and microbiological assays. Antifungal activities of the selected plant species were determined against three fungal pathogens namely, Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus. Of the tested plant species, hexane leaf extracts of M. juncea, ethyl acetate leaf extracts of S. italica, A. buchananii and E. elephantina were the most active against Candida albicans, Cryptococcus v neoformans and Aspergillus fumigatus with Minimum inhibitory concentration (MIC) values ranging between 0.02 mg/ml and 0.08 mg/ml. Bioautography assay was used to determine the number of active compounds in the plant extracts. No active compounds were observed in some plant extracts against the tested animal fungal pathogens indicating possible synergism. The most promising plant species were: A. buchananii, A. seineri and M. juncea, all had shown good activity with 4 compounds against A. fumigatus. Acetone and methanol extracts had the same active compounds visible on bioautograms. Most of the active compounds were observed in TLC chromatograms developed Benzene: ethanol: ammonia hydroxide (BEA) eluent solvent system. Based on excellent antifungal activity against the tested microorganisms, leaf extracts of A. buchananii, A. seineri M. juncea, P. insipidum and root extracts of I. circinnata were also tested for cytotoxicity against the Vero kidney cells. All plant extracts investigated were relatively not toxic against the cells with LC50 ranging between 0.131 mg/ml and  1 mg/ml. Water extracts of A. buchananii, A. seineri and M. juncea had LC50  1 mg/ml. The leaf aqueous extracts of P. insipidum were less toxic than root aqueous extracts of I. circinnata with LC50 of 0.65 mg/ml and 0.49 mg/ml against the Vero kidney cells respectively. The results indicate that the local people and traditional healers in Makhado Local Municipality use medicinal plants and their indigenous knowledge on the treatment of fungal infections and related ailments. / University of Limpopo and National Research Foundation (NRF)
213

Political Ecology of Medicinal Plant Use in Rural Nepal: Globalization, Environmental Degradation, and Cultural Transformation

Dovydaitis, Emily 01 January 2017 (has links)
Prior to the advent of biomedicine, rural communities in Nepal relied on phytochemically active compounds in medicinal plants as their primary source of medicine; however, ethnobotanical practices have shifted over time due to economic, environmental, and sociocultural stimuli. Findings from 2016 fieldwork conducted in Dumrikharka, Nepal and Tutung, Nepal are compared to existing literature to describe the political ecology of medicinal plants in rural Nepal. Anthropogenic climate change threatens individual plant species and ecosystem biodiversity. Globalized markets unabated by weak conservation programs place increasing demands on medicinal plants. As indigenous plants become overharvested and more difficult to access, Nepalis incorporate non-indigenous plants into the local pharmacopeia. Novel use of non-indigenous plants illustrates both the dynamic, resilient nature of traditional medicine systems and a loss of biodiversity. Social changes, including outmigration to other countries, notions of modernity, and preference for pharmaceutical drugs, reduce potential candidates to learn and preserve ethnobotanical knowledge. Waterborne pathogens caused by inadequate sanitation infrastructure continue to endanger Nepali populations. The dearth of clinical facilities throughout rural areas, when coupled with the decline ethnobotanical knowledge and traditional healers, poses a gap in healthcare jeopardizing vulnerable, marginalized populations. These factors reinforce the unequal distribution of resources in one of the world’s poorest countries, buttressing power inequalities and economic inequities.
214

Language Reclamation, Food Systems, and Ethnoecological Revitalization: A Case Study on Myaamiaki Ethnobotany and Community-Based Participatory Research

Melzer, Annie Maria January 2014 (has links)
No description available.
215

Functional diversity of indigenous diets in coastal Papua New Guinea : role in the nutrition transition and noncommunicable disease risk

Owen, Patrick. January 2008 (has links)
No description available.
216

Ethnobotany, Pharmacology, and Metabolomics of Antidiabetic Plants used by the Eeyou Istchee Cree, Lukomir Highlanders, and Q’eqchi’ Maya

Ferrier, Jonathan 15 January 2014 (has links)
A study was undertaken of plants used for treatment of diabetic symptoms by traditional healers of the Eeyou Istchee Cree (Canada), Lukomir Highlanders (Bosnia & Herzegovina), and Q’eqchi’ Maya (Belize). All antidiabetic plants were ranked by syndromic importance value (SIV) based on 15 symptoms, all of which were recognized by the Cree and Maya and 8 by the Highlanders. The Cree used only 18 species, the Highlanders 41, and the Maya 150, numbers which reflect the diversity of flora in their region. Vaccinium (Ericaceae) was one of the few genera in all three regions and the only consensus genus between the Cree and Highlander study sites. The Q’eqchi’ Maya ethnobotany did not present any cross-cultural consensus genera with Cree or Highlander medicinal plants, perhaps due to major biogeographic differences. In ethnopharmacological studies, Vaccinium species and Q’eqchi’ antidiabetic plants were tested in an assay relevant to diabetes, the advanced glycation endproduct (AGE) inhibition assay. Boreal and tropical Vaccinium species were potent inhibitors of AGEs and demonstrated concentration dependent inhibition, with a half maximal inhibitory concentration (IC50) range of 5.93–100 µg/mL. Phenolic content ranged from 80.3 to 201 µg/mL in boreal samples and from 1470 to 2170 µg/mL in tropical samples. Tropical species have a greater phenolic content and AGE inhibition. Seven Q’eqchi’ antidiabetic plant species were tested and all plant extracts showed AGE-inhibition. The IC50s ranged from 40.8 to 733 µg/mL, and the most active was Tynanthus guatemalensis Donn.. Tynanthus guatemalensis IC50 was about fives times greater (less active) than the mean ± SE IC50 reported for six tropical Vaccinium species of Vaccinium (8.77 ± 0.79 μg/mL). The highest consensus and most active Maya antidiabetic plant, Tynanthus guatemalensis Donn. Sm. was discovered to be an important plant recorded in archeological artifacts from the Late Classic Maya period (~750 CE). Ancient Maya used a cross shaped sign (k’an glyph) as a decorative element on Late Classic polychrome vessels and murals. The sign was believed to be the xylem template for a plant used as a flavouring in cacao drinks. However, the plant was incorrectly identified in the literature as Pimenta dioica (L.) Merr. (common name: Allspice) based on a common name and aromatic plant quality – not from a botanical voucher specimen. Pimenta dioica wood does not have a cross shape visible in the xylem but a unique character visible after a cross section of T. guatemalensis, is the xylem's cross shape organization. Wood of T. guatemalensis' also has an "allspice" aroma. Tynanthus guatemalensis is most likely the true botanical template behind the ancient Maya k’an glyph and this finding would show the continuity of use of this medicinal plant from ancient to modern times. Vaccinium was selected for an in depth phytochemical analysis using modern metabolomic methods. Nuclear magnetic resonance (1H NMR) was used to evaluate leaf extract spectra to provide information on (1) the taxonomic identity and (2) quantities of bioactive metabolites across multiple sites. Spectra clearly differentiated leaf samples of V. angustifolium, V. boreale, V. corymbosum, V. macrocarpon, V. myrtilloides, V. myrtillus, V. ovalifolium, and V. uliginosum according to generic, subgeneric, specific, phenotypic circumscriptions. Quantification of chlorogenic acid and hyperoside were replicated with a method that is highly reproducible across multiple sites with different NMR equipment. This methodology provides an important new approach to taxonomy and quality control for plants and natural health products.
217

Ethnobotany, Pharmacology, and Metabolomics of Antidiabetic Plants used by the Eeyou Istchee Cree, Lukomir Highlanders, and Q’eqchi’ Maya

Ferrier, Jonathan January 2014 (has links)
A study was undertaken of plants used for treatment of diabetic symptoms by traditional healers of the Eeyou Istchee Cree (Canada), Lukomir Highlanders (Bosnia & Herzegovina), and Q’eqchi’ Maya (Belize). All antidiabetic plants were ranked by syndromic importance value (SIV) based on 15 symptoms, all of which were recognized by the Cree and Maya and 8 by the Highlanders. The Cree used only 18 species, the Highlanders 41, and the Maya 150, numbers which reflect the diversity of flora in their region. Vaccinium (Ericaceae) was one of the few genera in all three regions and the only consensus genus between the Cree and Highlander study sites. The Q’eqchi’ Maya ethnobotany did not present any cross-cultural consensus genera with Cree or Highlander medicinal plants, perhaps due to major biogeographic differences. In ethnopharmacological studies, Vaccinium species and Q’eqchi’ antidiabetic plants were tested in an assay relevant to diabetes, the advanced glycation endproduct (AGE) inhibition assay. Boreal and tropical Vaccinium species were potent inhibitors of AGEs and demonstrated concentration dependent inhibition, with a half maximal inhibitory concentration (IC50) range of 5.93–100 µg/mL. Phenolic content ranged from 80.3 to 201 µg/mL in boreal samples and from 1470 to 2170 µg/mL in tropical samples. Tropical species have a greater phenolic content and AGE inhibition. Seven Q’eqchi’ antidiabetic plant species were tested and all plant extracts showed AGE-inhibition. The IC50s ranged from 40.8 to 733 µg/mL, and the most active was Tynanthus guatemalensis Donn.. Tynanthus guatemalensis IC50 was about fives times greater (less active) than the mean ± SE IC50 reported for six tropical Vaccinium species of Vaccinium (8.77 ± 0.79 μg/mL). The highest consensus and most active Maya antidiabetic plant, Tynanthus guatemalensis Donn. Sm. was discovered to be an important plant recorded in archeological artifacts from the Late Classic Maya period (~750 CE). Ancient Maya used a cross shaped sign (k’an glyph) as a decorative element on Late Classic polychrome vessels and murals. The sign was believed to be the xylem template for a plant used as a flavouring in cacao drinks. However, the plant was incorrectly identified in the literature as Pimenta dioica (L.) Merr. (common name: Allspice) based on a common name and aromatic plant quality – not from a botanical voucher specimen. Pimenta dioica wood does not have a cross shape visible in the xylem but a unique character visible after a cross section of T. guatemalensis, is the xylem's cross shape organization. Wood of T. guatemalensis' also has an "allspice" aroma. Tynanthus guatemalensis is most likely the true botanical template behind the ancient Maya k’an glyph and this finding would show the continuity of use of this medicinal plant from ancient to modern times. Vaccinium was selected for an in depth phytochemical analysis using modern metabolomic methods. Nuclear magnetic resonance (1H NMR) was used to evaluate leaf extract spectra to provide information on (1) the taxonomic identity and (2) quantities of bioactive metabolites across multiple sites. Spectra clearly differentiated leaf samples of V. angustifolium, V. boreale, V. corymbosum, V. macrocarpon, V. myrtilloides, V. myrtillus, V. ovalifolium, and V. uliginosum according to generic, subgeneric, specific, phenotypic circumscriptions. Quantification of chlorogenic acid and hyperoside were replicated with a method that is highly reproducible across multiple sites with different NMR equipment. This methodology provides an important new approach to taxonomy and quality control for plants and natural health products.
218

Patterns of harvest: investigating the social-ecological relationship between huckleberry pickers and black huckleberry (Vaccinium membranaceum Dougl. ex Torr.; Ericaceae) in southeastern British Columbia

Forney, Andra 05 May 2016 (has links)
For centuries the wellbeing of rural communities has depended on the health and resilience of local food systems. Over the last century many factors have contributed to declines in the availability and use of important traditional foods. In this thesis I have used black huckleberry (Vaccinium membranaceum) as a case study through which I explore the varying roles humans play in influencing the health of a wild forest food. Black huckleberry is one of the most sought after wild berries in British Columbia (BC). Over the past few decades huckleberry pickers and forest managers have expressed concerns over the decreasing quality and availability of these berries. To understand the different roles humans play in the ecology of black huckleberry I interviewed 17 long-time huckleberry pickers and participated in berry picking trips – in the East Kootenay region of southeastern BC. I also reviewed the academic literature on huckleberry ecology. I found that huckleberry pickers have a deep knowledge of factors affecting the health of huckleberry patches. They identify both shifting social-economic and ecological conditions in their local forests as intrinsically linked with declining huckleberry availability and health. In contrast, the scientific literature primarily focuses on ecological conditions and forest management practices, ignoring or downplaying the relationship of berry pickers to huckleberry ecology and overall quality. There are significant cultural differences between the berry pickers’ and the scientists’ views of the factors impacting the health of the berry patch. I argue that an effective approach to addressing the problem of declining quality and availability must include the valuable insights berry pickers have on how social-ecological factors affect berry health. / Graduate
219

Bark in traditional healthcare in KwaZulu-Natal, South Africa : usage, authentication and sustainability.

Grace, Olwen Megan. January 2002 (has links)
Healthcare in South Africa is polarised between western and traditional African systems of therapy. The latter is consulted by the majority of the population and therefore plays an integral role in the delivery of healthcare to South Africans. Traditional medicines are primarily plant products with long storage lives, among which the dominance of bark is typical of southern African traditional healthcare systems. Expansion of the traditional healthcare sector during the twentieth century, in response to rising consumer demands, stimulated a lucrative trade in medicinal plants that is centred in KwaZulu-Natal. Since herbal medicines are sourced almost exclusively from indigenous vegetation, harvesting pressures exerted on the indigenous flora to meet demands for traditional medicines have rendered such resources non-sustainable. Although trees comprise a small fraction of South African medicinal plant species, bark from them constitutes a substantial proportion of the plant products used medicinally. Trees are among the most threatened medicinal plants in South African due to their limited abundance, the ecological sensitivity of the vegetation in which they occur, and destructive methods of commercial bark harvesting that frequently take place within protected areas. In KwaZulu-Natal, bark is harvested primarily from forests that occupy an extent of only 0.1 % in the province. Conservation of economically valuable tree species is particularly problematic since data necessary for the establishment of sustainable usage systems are absent or inaccessible. Alternatives to in situ conservation for renewable bark resources include propagation, multi-use timber systems and reintroduction of locally extinct species. To facilitate appropriate management of bark resources, there is a need for specialist publications and consolidated data with which sustainable usage levels may be determined. The importance of bark in South African traditional healthcare is poorly reflected by the ethno botanical literature. In this study, 180 bark species used in traditional healthcare in KwaZulu-Natal were inventoried from thorough literature surveys, but this number is anticipated to be a conservative reflection of actual statistics. Where trade data were recorded in the literature, they indicated intensive exploitation of bark resources in KwaZulu-Natal and throughout South Africa, but conservation and management data were lacking for 72 % of the species inventoried. A number of problems were encountered in the literature, of which vague information and the documentation of local vernacular nomenclature were the most troublesome. Despite the importance of traditional medicine, the country's political history led to the prevailing situation, where the traditional healthcare sector is largely unregulated. Coupled with increasingly limited availability of medicinal plants, the quality and appropriate use of traditional medicines is negatively affected by growing numbers of inadequately trained practitioners, herbalist retailers and plant gatherers. Possibilities of misidentification or purposeful adulteration of medicinal bark products therefore lead to concerns for patient safety, since dried bark is difficult or impossible to identify. Whilst bark characters are useful for field identifications, many useful diagnostic characters are lost through desiccation, and anatomy and morphology of bark are variable. Additionally, medicinal bark products used in KwaZulu-Natal, and their identification, are largely undocumented. This study focussed on eight bark species used medicinally in the province, elected by an esteemed traditional medical practitioner as having problematic identity. Monograph-type characterisation profiles were drawn up for reference specimens collected from various localities, and their medicinal bark products traded under vernacular names recorded in the literature. In the absence of standardised traditional medicines, there is a need for reliable and affordable methods for their authentication. Phytochemical bark characters identified by Thin Layer Chromatography (TLC) have proved useful in chemotaxonomic studies, and the technique is widely used for herbal drug authentication. TLC was tested here for authentication of medicinal bark products from the aforementioned study species. Three reference samples of each species were collected, and TLC-generated fingerprints compared. At the intraspecific level, TLC was useful in confirming the relationship of ethanol and hexane bark extracts, but was less meaningful in distinguishing between fingerprints of different species. Three medicinal bark products of each study species were purchased and fingerprints compared to a reference. The technique proved useful in confirming the identity of several medicinal bark products. Authentication of medicinal bark products may be useful in toxicology cases and in the accurate documentation of their trade. This research identified a complexity of issues surrounding the use of bark in traditional healthcare in KwaZulu-Natal, and indeed South Africa. A multi-faceted approach is required to secure their sustainability. Critical, however, to factors such as effective conservation and regulation of the traditional healthcare sector, is recognition of the importance, and documentation, of traditional bark medicines. The integrity of traditional healthcare, and the future of the South African flora, hinge upon the sustainable use of medicinal products such as bark. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002.
220

Reconstruction of environments and plant use in Holocene Southern Africa : study of macrobotanical remains from Late Stone Age sites of Toteng (Botswana), Leopard Cave and Geduld (Namibia) / Reconstruction de l'environnement et des usages des plantes en Afrique australe pendant l'Holocène : étude de restes macrobotaniques provenant de sites du Late Stone Age de Toteng (Botswana), Leopard Cave et Geduld (Namibie)

Mvimi, Malebogo 06 June 2019 (has links)
A travers l'analyse de matériel macrobotanique (charbon et graines / fruits) issus de trois sites majeurs du Later Stone Age (LSA) d'Afrique australe, cette étude s'intéresse à reconstituer les conditions environnementales durant l'Holocène dans la région, en particulier au cours des deux à trois derniers millénaires. L'étude de ce matériel, accompagné de la constitution d'une collection moderne de références de la végétation du bassin Kgalagadi, vise à mieux cerner l'impact quel'environnement a pu avoir sur les sociétés humaines (subsistance, peuplements, etc.) à une période-clé du (LSA), qui marque l'émergence des pratiques pastorales dans la région. L'étude des environnements est ici primordiale pour interpréter les conditions qui ont pu favoriser l'arrivée de ces premiers éleveurs et leurs lieux d'installation. En complément, une approche ethnographique a été menée, en travaillant avec les communautés locales dans la région de l'Erongo en Namibie, qui peuvent aider à comprendre et reconstituer les pratiques passées d'utilisation de la végétation. / Through macrobotanical (wood charcoal and seeds / fruit) analysis from three major Later Stone Age (LSA) sites located in the Kgalagadi Basin in southern Africa, this study is interested in reconstructing the environmental conditions during the Holocene in the region, in particular in the last two to three millennia. Initially this work couples archaeological macrobotanical analysis with the construction of modern reference material in an effort to trace the environmental / vegetal evolution as well as to comprehend socio-ecological and socio-environmental dynamics in Southern Africa during the late Holocene. The scope of this study covers the period spanning the last 3000-2000 years, with the main objective of understanding what relationships humans had with their environment at a time linked with the arrival or the appearance of the first herding practices in that part of Africa. These herding practices are believed to be accompanied by significant human movement from eastern or central Africa southwards. Favourable environmental conditions may have influenced their routes as well as settlement choices, and these are aspects that this archaeobotanical study aims to address. This study also employed an ethnographic approach, working with local communities in the Erongo region of Namibia, so as to make inferences to past vegetation utilisation practices while at the same time discerning and reconstituting past human activities.

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