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Traditional medicines prepared from Sutherlandia frutescens are used to manage diseases including HIV and cancer. This study aimed at isolating and identifying biologically active compounds isolated from S. frutescens. Sutherlandia frutescens plants were collected in Petrusburg and Paarl. Powdered plant material was extracted using ethanol or water and their metabolite composition was compared using UPLC-MS. A novel cycloartane, an acetylated variant of this compound as well as a Sutherlandioside B triterpenoid was isolated and characterised using chromatographic and analytical techniques such as NMR and UPLC-MS. Preliminary biological studies were conducted to assess the activity of plant extracts on cell toxicity, herpes virus replication and cytokine expression. The results of this study suggest that aqueous extracts from S. frutescens do not appear to be cytotoxic or show anti-herpetic activity, but may activate the immune system by increasing expression of IL-6, IL-10 and TNFα. Further research should be conducted to confirm and optimise these results. / Life and Consumer Sciences / M. Sc. (Life Science)

Στην παρούσα διδακτορική διατριβή εκθέτονται η χλωρίδα των Βαρδουσίων ορέων καθώς και τα δεδομένα που προκύπτουν από την διερεύνηση – ανάλυσή της. Στο πεδίο της βλάστησης (φυτοκοινωνιολογία), έχει επιβεβαιωθεί σχεδόν το σύνολο των προηγούμενων αναφορών και έχει συμπληρωθεί με νέα δεδομένα όσο αφορά τις φυτοκοινωνιολογικές ομαδοποιήσεις. Συγχρόνως δικαιολογήθηκε και εξηγήθηκε η ύπαρξη των φυτοκοινωνιολογικών μονάδων σε σχέση με το σύνολο των οικολογικών παραγόντων που ήταν δυνατό να ληφθούν υπόψη (μικροκλίμα, εδαφικοί παράγοντες, γεωλογικό - πετρολογικό υπόστρωμα), συμβάλλοντας έτσι στην συνοικολογική προσέγγιση του θέματος. Επίσης όπου ήταν δυνατό έγινε προσπάθεια να διερευνηθεί η δυναμική εξέλιξης των περισσότερων φυτοκοινωνιολογικών ομάδων, όπως αυτή διαμορφώνεται κάτω από την επίδραση των περιβαλλοντικών μεταβλητών. Πιο κάτω ακολουθεί μια συνοπτική περιγραφή των σημαντικότερων σημείων της διδακτορικής διατριβής, καθώς και τα συμπεράσματα που μπορούν να διατυπωθούν από τα αποτελέσματα της ερευνητικής αυτής προσπάθειας. / In the present doctoral thesis the flora of Mt. Vardousia, as well as the data that have resulted from its analysis are presented. From a vegetation (plant sociology) point of view, almost all the previous reports on the mountain have been confirmed and have been enriched with new data as far as phytosociological groups are concerned. Additionally, the existence of certain phytosociological units was justified and explained based on the ecological factors that were possible to be measured (microclimate, soil, geology, geological substrate), contributing in this way to the synecological approach of the subject. Also, where feasible, an effort was done to study the dynamics of succession of most of the phytosociological groups, as they depend on various environmental variables. A concise description of the most important points of the doctoral thesis, as well as the conclusions that can be extracted from the results of this research follow.

Background: Access to safe water and sanitation are universal need and basic human right, but the provision of quality water and improved sanitation remains a challenge in many African countries including Ethiopia. Objectives: The study investigated drinking water quality, sanitation-hygiene practices and the potential of Moringa stenopetala seed powder for the purification of water in Bale Zone, Southeast Ethiopia. Methodology: A community-based cross-sectional study was conducted among 422 randomly selected households in Robe and Ginnir Towns. Data were collected by interviewer-administered structured questionnaires from June 2012 to August 2013. An observation checklist was used to observe the sanitary condition of water sources. A total of 71 water samples were collected using sterile glass bottles in accordance with the standard method of American Public Health Association APHA. The physicochemical and bacteriological water quality analyses were done in Addis Ababa Environmental protection and Oromia water and Energy laboratories. The efficiency of Moringa stenopetala seed powder for removal of turbidity, hardness, and nitrate was evaluated. Data were analyzed SPSS Version 21.0 for the window. Descriptive analysis was done for appropriate variables. Logistic regression was used to identify the factors associated with under-five diarrhea. The results were presented using adjusted odds ratio and P-value of < 0.05 was used to declare significance association. Results: From the total sample, 401 respondents participated making a response rate of 95%. More than one third (37.9%) of the respondents were found to use pipe water. Two hundred and eighty (69.8%) of households wash storage containers before refilling and 325 (81%) of households were using separate containers for water storage. Two hundred seventy (67.3%) of the households had pit latrine. Prevalence of childhood diarrhea was found to be 50.1%. From the logistic regression model, those households having access to clean water source are 68% less likely to have under-five diarrhea, the households having clean storage of drinking water are 45% less likely to have under-five diarrhea in their home, and those households having poor latrine sanitation are 68% more likely to have under-five diarrhea in their home. Seed powder of 200mg/l Moringa stenopetala reduced the Nitrate concentration doses from 5.49mg/l to 8.18mg/l, a 75mg/l was reduced the turbidity from 4.49NTU to 1.07 NTU. A total hardness of 427 was reduced by 7.8% after treatment with powder seed of Moringa stenopetala. Conclusion: Prevalence of childhood diarrhea was high and it is associated with lack of access to a clean water source, poor sanitation of drinking water storage and latrine. Prevalence of open field defecation was remarkably high. The iron content of drinking water was above the range of World Health Organization standards. Moringa stenopetala seed powder has efficiency in the reduction of total and faecal coliform, turbidity, hardness and nitrate level in drinking water Recommendation: Health education on water handling, sanitation and low-cost effective water treatment methods like Using Moringa stenopetala seed should be practiced at the household level. / Environmental Sciences / Ph. D. (Environmental Science)

The most recent surveys in South Africa estimate that invasions are still increasing, despite substantial clearing efforts. Riparian systems in South Africa are particularly vulnerable to invasion by woody IAPs. This thesis addresses the restoration of alien‐invaded riparian systems, by investigating the factors that facilitate or constrain spontaneous recovery and influence the trajectories of succession. These factors include invasion history and management history, especially the use of fire. A seedling emergence approach was used to test the presence of a viable pre‐fire seedbank, and the effect of fire on the seed bank. The efficacy of some active restoration interventions was also tested, with the aim to return invasion‐resistant, indigenous vegetation with a structure and function representative of uninvaded sites. The findings of this study indicated the presence of a viable and persistent riparian soil seed bank, even after 30 years of intermtittent invasion as well as two fire cycles under invasion. It shows that the management practice of fell‐and‐burn resulted in high soil temperatures, and that this reduced the indigenous soil seed bank density, especially in the upper soil layer. Clear germination sequences and patterns of emergence over time for different species were observed during this study, with many species exhibiting delayed emergence relative to the timing of the fire event. It is proposed that manipulation of the season of fire could be used to selectively optimise the order of arrival and therefore superior recruitment of some species over others in the Eastern Cape fynbos, and thus alter the trajectories of recovery of vegetation towards a more desired state. Active restoration in the form of indigenous seed and plant additions resulted in a significantly higher indigenous cover after seven months, compared to a control (passive restoration) or restoring with grass. Indigenous cover and composition was also strongly influenced by lateral zonation, and some key guilds and species were missing or present in much lower densities compared to reference sites. Grass restoration significantly suppressed the regeneration of A. longifolia, as well as the regeneration of indigenous species. Biotic resistance can thus be achieved through restoration, and it could be a powerful tool in the management of IAPs, although the deliberate introduction of grass after clearing in fynbos also reduces biodiversity and could have unforeseen consequences to riparian function.

This work is a school-based case study conducted amongst learners of a rural High School and the immediate community in Whittlesea in the Eastern Cape where I teach. The research was conducted by using different research methods such as worksheets, questionnaires, interviews, practical activities and observations as well as photographs to investigate three indigenous wild local vegetable food plants (imifino). The fundamental assumption of the research is that, imifino can be looked after and cared for, to become valuable vegetable food plants which can be used as supplements to the cultivated vegetable food plants (umfuno). The question was: How could this concept be brought into the curriculum? It had also been assumed that bringing knowledge of imifino into curriculwn contexts could be of benefit to South African learners. The study produced a variety of findings: • There is a general feeling that those who eat imifino are the poor. • There is a lack of interest among women interviewed in the preparation process, for example going to pick the food plants from the fields, washing them and preparing the leaves as food. • AmaXhosa males look upon eating imifino with contempt. • Some males among the younger generation are beginning to overlook tradition and are eating imifino. • Inclusion of indigenous agricultural knowledge in the curriculum was supported by learners and community members. Learners have interest in knowing about indigenous food plants. • Learners feel as Africans that they must learn about the indigenous food plants in school in order not to lose knowledge of these plants completely. • The study also identified that interpretation of learning outcomes with an indigenous knowledge focus, requires careful attention to socio-cultural factors, and not just technical/ practical factors. Previous knowledge of learners and community members about imifino was mobilized to develop a sample OBE learning programme unit (LPU /Lesson plan) for the Grade 10 FET of Agricultural Science curriculum. The case study illustrates that Learning outcome 3 of the Agricultural Science subject can be achieved if educators involve learners and community members in developing learning programmes.

Aphthona spp. flea beetles were released in the Little Missouri National Grasslands (LMNG) in western North Dakota in 1999 to control leafy spurge (Euphorbia esula L.). The changes in soil seed bank composition and leafy spurge density were evaluated on two ecological sites five (2004) and ten years (2009) after Aphthona spp. release to monitor the effectiveness of the insects on weed control and associated change in plant communities. In 2009, leafy spurge stem density averaged 2 and 9 stems m-2 in the loamy overflow and loamy sites, respectively, compared to 110 and 78 stems m-2, respectively, in 1999 and 7 and 10 stems m-2, respectively, in 2004. Leafy spurge constituted nearly 67% of the loamy overflow seed bank in 1999 compared to 17% in 2004 and 2% in 2009. In the loamy seedbank, the weed represented nearly 70% in 1999 compared to approximately 11% in 2004 and 15% in 2009. As leafy spurge was reduced, native species diversity and seed count increased ten years following Aphthona spp. release. High-seral species represented 17% of the loamy overflow seedbank in 2009, an increase from 5% in 1999. However, Kentucky bluegrass, a non-target weedy species, increased over 250% in the loamy overflow seedbank from 2004 to 2009. The reestablishment of native plant species has often been slow in areas where leafy spurge was controlled using Aphthona spp. A bioassay was completed to evaluate native grass establishment when grown in soil from Aphthona spp. release and non-release sites throughout North Dakota. Native grass production was not affected when grown in soil collected from established Aphthona spp. sites (1.5 g per pot) compared to soil without insects (1.6 g per pot). The cause of reduced native grass production in sites with Aphthono spp. previously observed is unknown but may have been due to a chemical inhibition caused by the insects within the soil that no longer exists. The native warm-season switchgrass (Ponicum virgotum L.) may be an alternative to corn for efficient biofuel production; however, control of cool-season grassy weeds has been a problem in switchgrass production. Various herbicides were evaluated for smooth bromegrass (Bromus inermis Leyss.) and quackgrass [Elymus repens (L.) Gould] control in an established switchgrass stand near Streeter, ND and a weed-infested field in Fargo, ND. Switchgrass yield was higher than the control 14 mo after treatment (MAT) when aminocyclopyrachlor or sulfometuron were applied early in the growing season, but no treatment provided satisfactory long-term grassy weed control. Herbicides were reevaluated at increased rates for smooth bromegrass or quackgrass control in Fargo. Sulfometuron provided 99% smooth bromegrass control when applied at 280 g ha-1 in the fall but injured other grass and forb species as well. Sulfometuron would likely be injurious to switchgrass and could not be used for biofuel production. Aminocyclopyrachlor did not injure other grass species but only reduced smooth bromegrass control by 76% when applied at 280 g ha-1 in the fall. No treatment provided satisfactory long-term quackgrass control.

MSCAGR (Plant Production) / Department of Plant Production / Indigenous trees play important roles in livelihoods for rural communities. Sclerocarya birrea and Berchemia discolor are indigenous in Africa and are used in rural communities for food and livestock feed, as well as for medicinal and construction purposes. These trees are subject to attack by insects, which can result in lower tree productivity. However, there is no documented information about insects found on both tree species in South Africa. This study investigated the seasonal abundance and diversity of insects on S. birrea and B. discolor in Tshikundamalema Area, Limpopo Province, South Africa. Five trees were selected for each of the two tree species at two sampling sites with different vegetation cover, one site mainly the woodland bushveld while the other site was savannah grasslands. Canopy fogging was used to sample insects. Insect samples were collected at one time point for each of the seasons: summer (February), autumn (May), winter (July) and spring (November). Insects were identified to morphospecies and Simpson’s diversity index was used to compare insect diversity on both trees. Analysis of variance was used to compare the abundance of insects across seasons. The most abundant insects were collected from Coleoptera, followed by Hemiptera, Hymenoptera, Diptera, Lepidoptera and Orthoptera. A total of 3259 insects belonging to the six Orders were collected. All specimens belonging to Coleoptera, Hemiptera and Hymenoptera (3216 in total) were identified to Family level, with a total of 97 morphospecies, belonging to 19 Families. Insects from Diptera, Lepidoptera and Orthoptera were not identified further due to their low numbers. The abundance and diversity of insects were affected by seasons, sites and tree species. The number of insects was high during the spring season with 1782 insects, and summer coming second with 1104 individuals, followed by autumn (238 insects), then winter (92). B. discolor sampled for a great number of insects (1741) as compared to S. birrea (1475). The woodland bushveld (1924 insects) surpassed the savannah grassland (1292 insects) site in terms of the insect numbers sampled. / NRF

The daunting tasks of responding to climate change and ensuring sustainable development (SD) are high on the political agenda among world leaders. From the onset, the clean development mechanisms (CDM) outlined in Article 12 of the Kyoto Protocol (KP), state that CDM activities should contribute to SD in the host country while reducing greenhouse gas (GHG) emission. Nevertheless, many scholars have criticized CDM for failing to deliver on its twin objectives. In Ethiopia in particular, there was lack of afforestation/reforestation (A/R) CDM research specific to the nation; specifically, research as to whether A/R-CDM met the stipulated twin objectives of SD and mitigation (reducing GHG). This study was conducted in the Humbo district of Wolyaita Zone, Southern Nations - Nationality and People Regional (SNNPR) state of Ethiopia, where A/R-CDM was implemented in pursuit of these twin objectives. Humbo is located between 6°46’48.47 and 6°41’04.28N; and between 37°48’35.44 and 37° 55’14.51E, between altitudinal gradients 1200 and 1900 m.a.s.l. The climate of the study area is characterized by annual temperatures between 25°C and 28°C, and by total annual rainfall between 800 to 1000 mm. The objectives of the study were to quantify the change of above ground and below ground carbon pools of native tree species; to assess the attractiveness of FMNR forestry practices; to examine A/R-CDM contributions to community level SD; and to assess the effectiveness of climate change mitigation policy founded on native tree species-based A/R-CDM. Data regarding above ground biomass (AGB) and below ground biomass (BGB) carbon pools of native tree species was collected through non-destructive techniques to quantify the change in carbon sequestration and associated carbon trading. A multi-stage random cluster household (HH) sampling approach was used to assess the attractiveness of farmer managed natural regeneration (FMNR) forestry practice. To examine the contribution of A/R-CDM to community level SD, three dimensions of SD were evaluated, namely; (local) environmental, social, and economic. Two indicators were considered per each dimension. With regard to local environmental SD, community access to natural resources, as well as changes to the local climate were considered. With regard to the social dimension, job creation and changes to social support structures were considered. With regard to the economic dimension, economic activities of the area and local skill development were considered. Focus group discussions and key informant interviews were used to triangulate the survey as well as to assess policy perspectives. Results revealed that the Humbo native tree species based A/R-CDM, which employed FMNR forestry practices, sequestered a net total of 73,138; 84,848; 103,769 and 111,657 tCO2e along 2011, 2014, 2015 and 2016 years, respectively, across 2,728 ha. In terms of carbon leakage due to fuel wood collection activity displacement, a net zero was found since the average volume of fuelwood collected from the project area, after the area was closed off, was found to be 5.1 - 6.1 M3, while before the area was closed off, that number was 4.3 M3. This was due to the project employing FMNR forestry practices. Similarly, the leakage due to livestock grazing activity displacement also was found to be a net zero, since the number of animals grazing on land adjacent to the project area after four years of the area’s being closed off reached 11,383 cattle, 429 donkeys and 4,108 goats, unlike 8,684 cattle and 2,288 goats before the project. In other words, the number of livestock owned by farmers on the land adjacent to the project site was not adversely affected by the closing off of the site, which prevented grazing on the area allocated to A/R-CDM. The livestock management training provided by project developer improved the farmers’ rearing efficiency. Another expected leakage due to soil pitting for A/R was also found to be nil since soil disturbance did not take place because of FMNR practices. These results indicated that systematic regeneration of native tree species through FMNR forestry practices is an effective method to develop carbon sinks. From the point of view of FMNR attractiveness, the results revealed that the practice improved land cover change. The use of FMNR avoided the projected eight years reforestation investment cost of US$ 2,751,312.00 which could have been used if plantation forestry was undertaken. This showed that Humbo A/R-CDM might not have happened if FMNR is had not been introduced, as CDM has no pre-finance mechanism. With regard to community level SD contributions, the establishment of forest protection and development farmers’ cooperatives, as well as the granting of communal land-user rights certification, resulted in legal ownership of the land to the community, whereas before, the land was considered “no man’s land,” and subject to open access. The land-user rights and carbon ownership in turn empowered the community to sign a contract with an international carbon credit buyer. In terms of the local microclimate, the regeneration of native tree species was correlated with increased rainfall in the area in June, July, August and September (JJAS) and March, April and May (MAM). This suggested that the native tree species based A/R-CDM project played a role in improving the local microclimate. In terms of sociological SD, the study showed that new employment opportunities were created including tree pruning, thinning, forest guarding, and jobs at the community warehouse and community flourmill. The availability of employment opportunities was significantly higher for those who participated in the Humbo A/R-CDM, when compared to those who didn’t. In terms of social support structures, in less than ten years, seven Humbo A/R-CDM project owner farmers’ cooperatives, initially established as owners of the project, evolved into one forest protection and development Union. This enabled the institutionalization of grassroots organizations towards a common communal and international agenda of care for the environment. In terms of economic effects, the project enabled a carbon credit contract worth a total of US$ 3,873,298.00, signed at the sell rate of US$ 4.4 per tCO2e, for a total of 880,295 tCO2e across a 30 year crediting period. This is a new business model for the community, the country, and global businesses, all doing their part in climate change mitigation - CDM. As of the first A/R-CDM verification, the community received a total of US$ 321,807.2 in 2011. Consequently, the community received 373,331.2 in 2014, 456,583.6 in 2015 and 491,290.8 in 2016. In terms of revenue from logging, selective harvesting is planned to take place in years 12, 24 and 36. The community is projected to earn at least US$ 15,150.00 per ha1 (a total of US$ 3.9 million) from the first forest harvest in year 12 alone. These benefits in emission reduction (ER) and SD suggest that massive cross-dimensional benefits were foregone due to the country’s refusal to welcome A/R-CDM in its first commitment period, despite having 36,434,400 ha of land eligible for A/R. The research results in the area of policy perspectives indicated that the Humbo A/R-CDM project, the only one of its kind in Ethiopia, was made possible by environment related constitutional provisions, especially those pertaining to land-user rights, and the existence of a nationally standardized definition of forest that complies with international range. Additionally, the timely ratification of the Kyoto Protocol (KP), the establishment of a designated national authority (DNA) and a letter of approval by the DNA to the project developer were found to be enablers. Yet, defining land use, clarifying carbon ownership rights and bringing an inclusive benefit sharing mechanism for forest carbon are among the key instruments the country has yet to put in place to prove local readiness for such development opportunities. The Humbo A/R-CDM also undertook voluntary assessments to obtain additional certification in the form of the Climate Community Biodiversity (CCB) certification, and was certified to be of gold standard for its premium. However, there were no benefits to the host community and project developer from the CCB gold standard certification. Such ambiguity could have been cleared from the onset. This implied whenever going for market and/or result based climate change mitigation, it is necessary to understand the provisions. This study revealed that the Humbo native tree species-based A/R-CDM via FMNR forestry practices met the CDM twin objectives as specified in Article 12 of the KP in 1997, namely the double aims of achieving mitigations of GHG emissions and assisting developing countries inSD. Yet, more research is needed to understand all eligible A/R carbon pools sequestered at Humbo A/R-CDM site. / Environmental Sciences / Ph. D. (Environmental Management)

South Africa has over 19 500 different indigenous plant species. Most of these are of ethnobotanical significance and are still used by local rural communities as medicine, food and for making beverages. The relatively little research that has been conducted on indigenous plant species has focused mainly on their medicinal potential. However, in view of the rapidly growing size of the global and local beverage industry and their constant search for new products, beverage-making indigenous plant species may have commercial development potential. To date, no detailed studies have been conducted on these plants, especially in the species-rich Limpopo province. The aim of this study was, therefore to evaluate the potential of indigenous plants for commercial beverage production. In order to achieve this, a survey was conducted in the Limpopo province to identify beverage-making plants and to document beverage preparation methods. Selected beverages were analysed and evaluated for their nutrient and sensory characteristics and a market product acceptability survey was conducted to identify those beverages with the greatest potential for development. Sixty three different beverage-plant species were identified in three study areas within the Limpopo province. These were used for the preparation of teas, fruit juices and alcoholic beverages. Plants that received further research attention were selected on the basis of their status as indigenous plants, frequency of use, nature of harvesting methods and availability. Some of the selected beverages were found to be rich in nutrients, especially with respect to vitamin C and mineral content. Furthermore, sensory analyses and market surveys indicated that four species, namely, Doyvalis caffra, Garcinia livingstonei, Grewia flavescens and Englerophytum magalismontanum have potential for further development for the beverage industry while Athrixia phylicoides has commercialisation potential as a herbal tea. However, further research is required to improve and refine preparation methods and to ensure compliance with quality standards. The availability of sufficient plant material for the industry must also be ensured. This research has indicated that South African indigenous plants have untapped market potential for the beverage industry which, if developed sustainably, could contribute to economic growth of the rural parts of South Africa. / Environmental Sciences / D. Ed. (Environmental Management)