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Bird-Monk Seding

- Rampolokeng, Lesego

Authors: Rampolokeng, Lesego
Date: 2017
Language: English
Type: Thesis , Masters , MA
Identifier: http://hdl.handle.net/10962/5049 , vital:20758
Description: This novella is made up of interlinked stories from a rural township in the North West province. The stories of this surface-tranquil place are told through descriptive passages, vignettes, snatches of dialogue, profiles and picture-postcards, all organically interwoven and entwined, and rendered in non-linear fashion. They are set in shebeens, shops, farmlands and the dusty empty spaces of the South African landscape, peopled by police, tourists, and prostitutes of all sorts. The pervasiveness of violence in all forms has the fictional narrator reflecting on the violence of his own past. A smattering of musicians' musings gleaned from interviews and album liner-notes helps him navigate his way through this morass, the rage and frustration that simmers beneath it all.
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Birds as major predators of fishes in the East Kleinemonde Estuary

- Cowley, Paul D, Whitfield, Alan K, Terörde, Anja I

Authors: Cowley, Paul D , Whitfield, Alan K , Terörde, Anja I
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/443271 , vital:74104 , https://hdl.handle.net/10520/EJC-c2893c53c
Description: This study provides a quantitative account of fish predation by piscivorous birds in the temporarily open/closed East Kleinemonde Estuary and represents the first global attempt to simultaneously relate such consumption to production by a fish community in the same estuary. Cormorants and herons were the dominant predators and seasonal variations in the avifaunal community composition were noted. Based on comprehensive counts over three years, the piscivorous bird population was estimated to have consumed a maximum of 4 414 kg of fish in 1994, 2 400 kg in 1995/96 and 2 960 kg in 2004/05. In 1995/96 fish production in the East Kleinemonde Estuary (55.89 g m−2 a−1) was estimated at 9 780 kg and maximum bird predation amounted to 25% of annual fish production within the system over the same period, assuming that all birds counted on the estuary foraged there and that the diet of these birds comprised only fish. The above 1995/96 figures, together with an estimate of fish predation by the dominant piscivorous fish Lichia amia of 696 kg suggests that birds are probably the single most important natural predator of fishes within this estuary. An unusual mass invasion by marine Cape Cormorants Phalacrocorax capensis during July 1994 was responsible for large-scale predation of fish (2 155 kg) and resulted in the population of estuary-associated marine fishes declining from approximately 63 300 to about 18 600 individuals during the 1994 closed phase. Given that little or no marine fish recruitment was possible while the estuary mouth was closed, piscivorous birds are likely to have a higher predatory impact on populations of juvenile marine fishes in small temporarily closed estuaries than in larger permanently open systems.
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Book Review: Losing the Plot. Crime, reality and fiction in postapartheid writing

- Naidu, Samantha

Authors: Naidu, Samantha
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/124942 , vital:35712 , https://dx.doi.org/10.17159/tvl.v.54i2.2980
Description: In this wide-ranging and impressive ac¬count of postapartheid writing, De Kock describes the “dizzingly heterogeneous corpus” (1) of South African literature after apartheid with the aim of describing its distinctive features and complexity. The methodology is straightforward. De Kock has chosen to read particular liter¬ary works in order to identify broader ideas and trends. To contextualise the study, De Kock deploys the key, perva¬sive notion of “transition”. The notion is variously defined as a “transformative shift from one ‘state’ to another” (2), a “popular mythology” in the “collective consciousness” (3), and as containing a counter-discourse of disillusionment or disorientation, which De Kock refers to as “‘plot loss’” (3). This “plot loss” becomes a central trope in the book to express the social and political chaos of the country, evident in various criminal manifestations of neo-colonialism such as neo-liberal economic policies, new forms of racism, and corruption.
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Boundary making and boundary crossing in learning pathways access and progression: Voices from the workplace

- Lotz-Sisitka, Heila, Mohanoe, M Nthabiseng, Ramsarup, Preesha, Olvitt, Lausanne L

Authors: Lotz-Sisitka, Heila , Mohanoe, M Nthabiseng , Ramsarup, Preesha , Olvitt, Lausanne L
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , bulletin
Identifier: http://hdl.handle.net/10962/436374 , vital:73265 , ISBN bulletin , https://www.saqa.org.za/wp-content/uploads/2023/02/SAQA-Bulletin-2017-1.pdf#page=37
Description: In the South African Qualifications Authority and Rhodes University (SAQA-Rhodes) partnership research it was found that ‘researching the boundary’is an important unit of analysis in learning pathways research (see Papers 1 and 2 in this Bulle-tin). The researchers have argued that this focus has rele-vance for discussions on articulation, as articulation is a boundary crossing practice39. However, to understand boundary crossing processes, it is important to understand what the boundaries are in learning pathways research and to understand how these boundaries were developed. Bounda-ries in learning pathways are both social and material and are constructed by people’s actions and practices, and can only be resolved through people’s actions and practices. This pa-per–Paper 5–considers the manner in which social-material factors are ‘boundary makers’ in learning pathways, affecting access, mobility, progression and articulation possibilities, with specific reference to articulation between workplace experi-ences and contexts on one hand, and education and training systems on the other. The paper argues for a perspective on the social-material that includes the Critical Realist concept of ‘absence’(Bhaskar, 1993) as an important shaping force in learning pathways research (see Paper 4, in this Bulletin). By identifying ‘boundary making’processes and factors, as articu-lated through ‘voices in the workplace’[one perspective on this issue], the paper identifies key areas for ‘boundary cross-ing’practices in the South African National Qualifications Framework (NQF) system and its associated sub-systems.
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Breaking the silence on abortion: the role of adult community abortion education in fostering resistance to norms

- Bloomer, Fiona, O'Dowd, Kellie, Macleod, Catriona I

Authors: Bloomer, Fiona , O'Dowd, Kellie , Macleod, Catriona I
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/444250 , vital:74210 , xlink:href="https://doi.org/10.1080/13691058.2016.1257740"
Description: Meanings of abortion in society are constructed within sociohistorical and gendered spaces and manifested through myriad discourses that impact on the perception and treatment of the issue in that society. In societies with powerful oppressive anti-abortion norms, such as Northern Ireland, little is known as to how these norms are resisted by the adult population. This study uses a Foucauldian feminist approach to show how resistance to religious and patriarchal norms can be fostered through adult community abortion education. This resistance is multi-faceted and bolstered by a lived experience discourse, which does not necessarily involve eschewing religious notions held within society.
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Browsing as a demographic bottleneck in a semi-arid savanna: the effect of size and age on compensatory responses of Vachellia karroo seedlings after simulated herbivory

- Perumal, Lavinia

Authors: Perumal, Lavinia
Date: 2017
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10962/4899 , vital:20741
Description: Savannas are characterised by a continuous grass layer with scattered trees at varying densities. This vegetation structure is determined by several interacting factors, including fire, herbivory, resource competition and atmospheric CO2 concentration. The preservation of savanna biomes is important and a shift towards a woody biome threatens savanna globally. Bush encroachment which describes the shift towards domination of savannas by C3 woody plants, is especially acute in southern Africa. In semi-arid rangelands, encroachment progresses to dense thickets dominated by thorny and unpalatable bushes and trees. There is evidence that bush encroachment is driven by a reduction in fire and browsing events as well as their interaction. Despite browsing having strong effects on African savannas its isolated role in maintaining tree-grass coexistence has not received as much attention as the role of fire. Therefore the overall aim of this study was to examine the effects of browsing on seedlings of a commonly encroaching species, Vachellia karroo. Browsing was hypothesized to be a demographic release bottleneck for bush encroachment in a semiarid (MAP ~550mm) savanna in the Eastern Cape of South Africa, where fire has been historically rare. In a single study I explored the fate of V. karroo seedlings (less than a year old) following browsing in sub canopy and inter canopy microhabitats. Additionally, I explored how the fate of a seedling changed under high and low tree cover. Firstly, I investigated the type, intensity and frequency of herbivory, from both small and large herbivores, which seedlings were subjected to. Results revealed that browsing was severe and frequent with the majority of seedlings browsed more than twice over a 12 month period. Large browsers such as kudu and impala caused high seedling mortality (46%) while smaller browsers such as invertebrates were more effective at suppressing growth. Microhabitat had little impact on seedling survival, but significantly influenced plant compensatory growth. Reduced seedling growth following browsing was observed in the sub-canopy in comparison to seedling growth in full sunlight in the intercanopy, suggesting V.karroo may be shade intolerant. Secondly, the effect of tree cover on browsed seedlings was determined by quantifying browsing frequency and intensity at high and low tree cover. No differences in browsing intensity and frequency were observed between high and low tree cover. However, high tree cover due to bush encroachment limited seedling above ground growth. The aim of the second study was to investigate how V.karroo survival and growth were influenced by its age and size following simulated browsing. I explored this aim through field and greenhouse experiments. I was particularly interested in testing how plant sensitivity to varying defoliation intensities of repeated browsing varied with plant age (known ages of 6, 12, 16 and 30 weeks). There were large differences in mortality between the different age groups. Furthermore, age interacted with repeated browsing and negatively influenced seedling survival and regrowth. Older seedlings (16 and 30 week old) had greater survival and higher browsing frequencies resulted in greater mortality and reduced growth. The threshold age after which seedlings become more tolerant to herbivory occurs at an age of 28 weeks. Seedlings less than six weeks old experiencing intense (100 % defoliation)browsing had a very low probability (33%) of survival following just a single defoliation. Interestingly, all 16 week old seedlings regrew most of their foliage following a moderate (50%) defoliation with some plants overcompensating for leaf loss. The field study revealed two distinct demographic stages based on age and size (seedlings< 9 mm and saplings >9 mm in stem basal diameter (SBD)). Browsing had a strong negative effect on seedlings, resulting in reduced investment in leaf biomass. These findings suggest plant size and age can be used as robust predictors of a plants vulnerability to browsing. An increase in tree cover requires successful transitions of seedlings to saplings (also known as release). The results of this study suggest that in semi-arid savannas, browsing can impact tree cover through imposing a release bottleneck for tree seedlings and to lesser extent saplings. By limiting tree growth plants are kept in a disturbance trap and will therefore be exposed to not only browsers but fire. These findings also have important implications for tree-grass coexistence dynamics, suggesting that specific size and browsing thresholds should be considered in savanna management.
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Calibration and imaging with variable radio sources

- Mbou Sob, Ulrich Armel

Authors: Mbou Sob, Ulrich Armel
Date: 2017
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10962/37977 , vital:24721
Description: Calibration of radio interferometric data is one of the most important steps that are required to produce high dynamic range radio maps with high fidelity. However, naive calibration (inaccurate knowledge of the sky and instruments) leads to the formation of calibration artefacts: the generation of spurious sources and the deformations in the structure of extended sources. A particular class of calibration artefacts, called ghost sources, which results from calibration with incomplete sky models has been extensively studied by Grobler et al. (2014, 2016) and Wijnholds et al. (2016). They developed a framework which can be used to predict the fluxes and positions of ghost sources. This work uses the approach initiated by these authors to study the calibration artefacts and ghost sources that are produced when variable sources are not considered in sky models during calibration. This work investigates both long-term and short-term variability and uses the root mean square (rms) and power spectrum as metrics to evaluate the “quality” of the residual visibilities obtained through calibration. We show that the overestimation and underestimation of source flux density during calibration produces similar but symmetrically opposite results. We show that calibration artefacts from sky model errors are not normally distributed. This prevents them from being removed by employing advanced techniques, such as stacking. The power spectrums measured from the residuals with a variable source was significantly higher than those from residuals without a variable source. This implies advanced calibration techniques and sky model completeness will be required for studies such as probing the Epoch of Reoinization, where we seek to detect faint signals below thermal noise.
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Capital or critique?: when journalism education seeks to influence the field

- Boshoff, Priscilla A, Garman, Anthea

Authors: Boshoff, Priscilla A , Garman, Anthea
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/143392 , vital:38242 , DOI: 10.1080/02560046.2016.1262437
Description: Drawing on Bourdieu’s theories of field and capital, we examine the limitations that a journalism school at a prestigious university faces in making a meaningful contribution to the field within a developing country. In the postapartheid South African media landscape, journalism is under pressure both from global forces and a political imperative to address social justice. Given the heterogeneity of the journalistic field and the fact that what counts as capital in it is contested, the School of Journalism and Media Studies at Rhodes University attempts to redefine the parameters by inculcating a particular approach to and philosophy of journalism practice. While Rhodes wants to educate excellent (professional) journalists, it is guided by an overt political mission to cultivate a journalism that is not necessarily ‘in sync’ with the wider field. Ironically, most undergraduates come from the economic and cultural elite, with specific intentions to accumulate the capital which Rhodes bestows. Students are confronted with their privilege and with alternative ideas about the purpose of journalism, and are asked to make choices and take up positions. We consider whether this critical praxis approach is able to influence the ‘state of play’ – or the distribution of power – within the field.
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Carbon credit restoration projects in the Eastern Cape province of South Africa: considerations for sustainable local economic development

- Polak, James Samuel

Authors: Polak, James Samuel
Date: 2017
Language: English
Type: Thesis , Masters , MCom
Identifier: http://hdl.handle.net/10962/8069 , vital:21349
Description: Although global climate change has been identified as a serious global economic, social, and environmental threat to society, national governments have been slow to respond on a global scale. Environmental economic theory offers market-based solutions to address climate change efficiently through carbon control regimes, such as carbon taxation and cap-and-trade policy. A major political milestone was reached when an international agreement entered into force in 2008, known the Kyoto Protocol, which incorporated a market-based solution to address climate change on a global scale. This allowed a global market for emissions to form through the Clean Development Mechanism. Although the Kyoto Protocol aimed to address a global issue on a global scale through a single global market for emissions, fragmented sovereign cap-and-trade schemes have since emerged in the form of national and regional emission markets, commonly referred to as carbon markets. The Clean Development Mechanism offered the opportunity to generate carbon credits through carbon offset projects, such as carbon restoration projects. Although the Kyoto Protocol did not achieve the objective of forming an internationally accepted global carbon control regime, it seems to have set a trend of including offset programs in newly emerging carbon control regimes, such as South Africa’s proposed carbon tax. This study set out to assess the extent to which carbon control regimes are enabling sustainable local economic development, based on carbon restoration projects in the Eastern Cape province of South Africa using Portulacaria afra, commonly known as spekboom. As a starting point, this study assessed the current state of the international carbon markets using significant international cap-and-trade based markets as examples. Based on Newell et al.’s (2013) selection of significant carbon markets and data availability, the United States’ Regional Greenhouse Gas Initiative and the European Union’s Emission Trading Scheme were selected. Historical, current and forecasted supply and demand data were gathered from Thomson Reuters’ Point Carbon research division. Further, historical futures and spot market price and volume data were gathered from the markets to compare how prices have fared over time. The Clean Development Mechanism’s market for Certified Emission Reduction credits was used for comparative purposes. The markets were found to be systemically oversupplied, leading to systemically low prices. The systemic oversupply in credits provides a limited incentive to initiate carbon offset projects, however, South Africa’s proposed carbon tax may be able to stimulate demand for domestic offset projects. Key success factors established through a comparative literature review on local economic development theory were incorporated into key informant interviews. The results were then analysed through the lens of Connelly’s (2007) model for sustainable development to provide recommendations for sustainable local economic development, regarding carbon restoration projects in the Eastern Cape using P. afra. The following opportunities were identified: the planting of P. afra on degraded land has the potential to mitigate climate change, offer water benefits to the surrounding communities, and promote biodiversity regeneration. There is potential for economic growth through job creation and the economic multiplier effect. Government funding is available and voluntary offset agreements do exist, eliminating a large portion of the cumbersome accreditation requirements. These projects also offer potential for social justice through the government funding requirements which stipulate that youth and women should be given preference for employment, potentially helping to alleviate inequality. The funding further stipulates that employees should be trained in transferable skills, offering potential for capacity building and social capital accumulation through education. These transferable skills include skills geared towards encouraging entrepreneurialism. Corresponding challenges were also found: excessive overgrazing through pastoralism has rendered some land degraded beyond restoration. Opportunists may resort to planting P. afra outside of the subtropical Albany Thicket biome to which it is endemic, leading to potential biodiversity loss rather than gains. Sufficient buy-in is required from private landowners for these projects to be sustainable, however, the projects entail a large opportunity cost to farmers as returns take at least 5 to 6 years. This may render these projects undesirable to most landowners and provides scope for free-riding, should pastoralists not have to bear the full costs of the project and property rights not be enforced through land user agreements. The projects require an exorbitant amount of upfront funding. Cash flow received from the projects does not extend in perpetuity. Requirements for social justice pertain only to government funded projects. A working model, generating and selling carbon credits through land restoration using P. afra, has not yet been established. As it stands, these carbon restoration projects are still highly speculative and carry a significant amount of investment risk, given the high mortality and low growth rates associated with the current planting method. The current systemic oversupply of carbon. credits in the international markets signal that returns from carbon credits are set to be low, at least until the oversupply issues are resolved. Should these challenges be overcome, carbon restoration projects using P. afra may have the potential to bolster sustainable local economic development in the impoverished regions of province as well as provide a locally-driven adaptation and mitigation strategy to address global climate change.
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Cardiovascular disease risk in Black and Caucasian females: an Eastern Cape sample

- Remsing, Sandra Claudia

Authors: Remsing, Sandra Claudia
Date: 2017
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10962/40737 , vital:25021
Description: The purpose of this study was to investigate cardiovascular disease risk in Black and Caucasian urban working females of the Makana region of the Eastern Cape. One- hundred and sixty six age-matched urban-working individuals (Black n = 88; Caucasian n = 78) voluntarily participated in this cross-sectional study. Cardiovascular disease risk was assessed in four categories: 1) obesity, classified as ‘morphological risk’, 2) blood pressure, classified as ‘cardiovascular risk’, 3) diet, physical activity, smoking, and alcohol consumption, classified as ‘lifestyle risk’, and 4) education and income, classified as ‘socioeconomic factors’. Results showed that Black females were significantly (p<0.01) heavier than Caucasian females and categorized as ‘obese’ according to BMI classifications (31.19 ± 8.09 kg.m2 and 25.90 ±4.67 kg.m2, respectively). Black females also presented with significantly (p<0.01) higher waist circumferences and waist-to-stature ratios, further confirming the obesity prevalence in this group. When accounting for those who were on anti-hypertensive mediation, Black females additionally presented with significantly (p<0.05) higher blood pressure, categorizing them as ‘pre-hypertensive’ (MAP = 98 ± 16 mmHg and 85 ± 11 mmHg, respectively). These results therefore placed Black females at increased cardiovascular disease risk compared to Caucasian females. With respect to lifestyle factors, Black females consumed significantly (p<0.05) more kilojoules carbohydrates, and total sugar than Caucasian females, and expended more physical activity MET- minutes per week (2688.86 ± 1486.56 MET-minutes and 1828.27 ± 2238.10 MET- minutes, respectively). However, reduced validity of physical activity data as well as poor dietary recall limited the interpretations of these findings. In addition, despite significant differences between smoking and alcohol consumption between groups, the majority of both Black and Caucasian females reported being non-smokers and consumed alcohol minimally. Thus, these were concluded to be unlikely contributors to cardiovascular disease risk in these samples. Socioeconomic results nevertheless expectedly showed that Black females were significantly (p<0.05) less educated, and subsequently earned lower incomes. It was thus concluded that this may be a likely contributor to higher cardiovascular risk in Black females. Future recommendations include the incorporation of exercise intensity measures as well as objective measures of habitual diet. This is in order to get a clearer understanding of the impact of these lifestyle factors on cardiovascular disease risk.
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Cationic cyclodextrin/alginate chitosan nanoflowers as 5-fluorouracil drug delivery system

- Lakkakula, Jaya R, Matshaya, Thabo, Krause, Rui W M

Authors: Lakkakula, Jaya R , Matshaya, Thabo , Krause, Rui W M
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/125587 , vital:35798 , https://doi.org/10.1016/j.msec.2016.08.073
Description: Cyclodextrins (CDs) have widely been used as component of drug delivery systems. However unmodified cyclodextrins are associated with cytotoxicity and poor water solubility thus limiting their use in pharmaceutical industry. The cationic-β-cyclodextrin (Cat-β-CD) polymer cores were synthesized using β-CD, epichlorohydrin and choline chloride via a one-step polycondensation process. The main aim of this study was to synthesize hierarchical nanoflowers composed of cationic-β-CD as polymeric core along with alginate and chitosan “petals” (Cat-β-CD/Alg-Chi nanoflowers) as carriers for oral delivery of 5-Fluorouracil (5-FU) via an ionic-gelation technique. The drug loading capacity, particle size, zeta potential and surface morphology of the synthesized nanoflowers were determined. The prepared nanoflowers were formed with an average size of 300 nm and a zeta potential of + 9.90 mV with good encapsulation efficiency of up to 77.3%. In vitro release of 5-FU from the loaded nanoflowers showed controlled and sustained release compared to the inclusion complex alone. Cat-β-CD/Alg-Chi nanoflowers were assessed against L929 cells and found to be effectively inhibiting the growth of L929 cells in a concentration dependent manner.
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Challenges with modelling transcription factor binding

- Machanick, Philip, Kibet, Caleb K

Authors: Machanick, Philip , Kibet, Caleb K
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/439158 , vital:73551 , 10.1109/NEXTCOMP.2017.8016178
Description: Modelling transcription factor binding presents a number of challenges. In its simplest form, binding can be modelled by a consensus sequence but a number of factors including degeneracy of binding sites, alternative modes of binding and differences between artificially-constructed and in vivo DNA make modelling binding complex. In this paper we outline difficulties and report on progress with improving modelling of binding. We focus on improving measurement of binding models, a necessary prerequisite for finding better models.
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Change Drivers at the front lines of the future: rising cultures for sustainability education in contemporary South Africa

- Kulundu, Injairu

Authors: Kulundu, Injairu
Date: 2017
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/437107 , vital:73331 , ISBN 978-0-620-79605-7 , https://doi.org/10.3920/978-90-8686-846-9_33
Description: This chapter asks us to regenerate and re-imagine what a dis-tinctively young and contemporary feeling of Environmental and Sustainability Education could look like in the African con-text. It asks us to acknowledge the ingenious ways that Change Drivers in South Africa and Africa are moving towards their visions of the common good. The chapter invites us to trace and learn from the transgressive learning and nomadic journeys of young Change Drivers who are part of a network called Activate! Change Drivers. Activate! Change Drivers is one of the largest youth led movements in South Africa. It is a network of young leaders equipped to drive change for the common good in South Africa. In a world that is uncertain and unknown the embodied knowledge of Change Drivers in South Africa can help us as practitioners think carefully and critically about how to learn for an unknown and predominantly young future.
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Changes in chemical composition of essential oils from leaves of different Lantana camara L. (Verbenaceae) varieties after feeding by the introduced biological control agent, Falconia intermedia Distant (Hemiptera: Miridae)

- Ngxande-Koza, Samella W, Heshula, Lelethu U P, Hill, Martin P

Authors: Ngxande-Koza, Samella W , Heshula, Lelethu U P , Hill, Martin P
Date: 2017
Language: English
Type: article , text
Identifier: http://hdl.handle.net/10962/59834 , vital:27664 , https://doi.org/10.4001/003.025.0462
Description: Lantana camara L. (Verbenaceae) is one of the most problematic plant invaders in South Africa and has been targeted for biological control for over 50 years. Essential oil constituents which often change in response to insect herbivory are reported to play a crucial role in plant-insect interactions. However, nothing is known about the chemical profiles of essential oils of L. camara varieties in South Africa and how this changes under herbivory. Therefore, essential oils were collected using hydrodistillation from undamaged and insect-damaged leaves of four L. camara varieties and analysed using gas chromatography-mass spectrometry to elucidate their chemical profiles. A total of 163 compounds were identified from the undamaged leaves of the various L. camara varieties. Feeding by the biocontrol agent Falconia intermedia Distant (Hemiptera: Miridae) resulted in changes in the quality and quantity of chemical constituents of the essential oils. Only 75 compounds were identified from the insect-damaged leaves of L. camara varieties. Terpenes were the major components across the varieties, while caryophyllene, hexane, naphthalene, copaene and a-caryophyllene were common in all the varieties tested from both undamaged and insect-damaged leaves. Results from this study indicated the chemical distinctiveness of the Whitney Farm variety from other varieties. The changes in chemical concentrations indicated that feeding by the mirid on L. camara varieties causes an induction by either reducing or increasing the chemical concentrations. These inductions following the feeding by F. intermedia could be having a negative impact on the success of biological control against L. camara varieties. However, the focus of this paper is to report on the chemical baseline of L. camara varieties. Hence, comparisons of chemical compound concentrations of L. camara essential oils tested and the feeding-induced changes with respect to their quality and quantity are discussed.
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Changes in forest cover and carbon stocks of the coastal scarp forests of the Wild Coast, South Africa

- Mangwale, Kagiso, Shackleton, Charlie M, Sigwela, Ayanda

Authors: Mangwale, Kagiso , Shackleton, Charlie M , Sigwela, Ayanda
Date: 2017
Language: English
Type: article , text
Identifier: http://hdl.handle.net/10962/60903 , vital:27887 , https://doi.org/10.2989/20702620.2016.1255480
Description: Land-use intensification and declines in vegetative cover are considered pervasive threats to forests and biodiversity globally. The small extent and high biodiversity of indigenous forests in South Africa make them particularly important. Yet, relatively little is known about their rates of use and change. From analysis of past aerial photos we quantified rates of forest cover change in the Matiwane forests of the Wild Coast, South Africa, between 1942 and 2007, as well as quantified above- and belowground (to 0.5 m depth) carbon stocks based on a composite allometric equation derived for the area. Rates of forest conversion were spatially variable, with some areas showing no change and others more noticeable changes. Overall, the net reduction was 5.2% (0.08% p.a.) over the 65-year period. However, the rate of reduction has accelerated with time. Some of the reduction was balanced by natural reforestation into formerly cleared areas, but basal area, biomass and carbon stocks are still low in the reforested areas. The total carbon stock was highest in intact forests (311.7 ± 23.7 Mg C ha−1), followed by degraded forests (73.5 ± 12.3 Mg C ha−1) and least in regrowth forests (51.2 ± 6.2 Mg C ha−1). The greatest contribution to total carbon stocks was soil carbon, contributing 54% in intact forests, and 78% and 68% in degraded and regrowth forests, respectively. The Matiwane forests store 4.78 Tg C, with 4.7 Tg C in intact forests, 0.06 Tg C in degraded forests and 0.02 Tg C in regrowth forests. The decrease in carbon stocks within the forests as a result of the conversion of the forest area to agricultural fields was 0.19 Tg C and approximately 0.0003 Tg C was released through harvesting of firewood and building timber.
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Changes in household food security, nutrition and food waste along an agro-ecological gradient and the rural-urban continuum in mid-sized South African towns

- Chakona, Gamuchirai

Authors: Chakona, Gamuchirai
Date: 2017
Subjects: Food security -- South Africa , Women -- South Africa -- Nutritiona , Urban women -- South Africa -- Nutrition , Rural women -- South Africa -- Nutrition , Wild foods -- South Africa , Food supply -- South Africa , Malnutrition in children -- South Africa , Grants-in-aid -- South Africa , Household ecology -- South Africa
Language: English
Type: Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/6484 , vital:21127
Description: The lack of dietary diversity is a severe problem experienced by most poor households globally. Most poor communities are at high risk of inadequate intake of micronutrients resulting from diets dominated by starchy staples. The present study considered the diets, dietary diversities and food security of women of reproductive age between 15-49 years, households and communities along the rural-urban continuum in three mid-sized towns situated along an agro-ecological gradient in South Africa. A 48-hour dietary recall was performed across two seasons (twice in summer and once in winter) and focus group discussions were held to gather all information including food abundance, seasons of food scarcity as well as coping strategies which households employ during periods of food shocks. Households were further asked to quantify any type of food waste that they could have generated in the previous 48 hours. Nutritional status of children under the age of five in all three towns was also measured using height-for-age (HAZ) and mid-upper arm circumference (MUAC) as indicators of stunting and wasting respectively. The household surveys were conducted with 554 women randomly selected in rural, peri-urban and urban locations of Richards Bay, Dundee and Harrismith. For nutritional status, the sample consisted of 216 children who were randomly selected from the sampled households in rural, peri-urban and urban locations of the study sites. Household Dietary Diversity Scores (HDDS) and Women’s Dietary Diversity Scores (WDDS) were calculated from the food items consumed by each household and each woman over a two-day period, respectively. Household food access was also measured for each household using Household Food Insecurity Access Scale (HFIAS). The mean WDDS and HDDS for the wettest site of Richards Bay (3.8±0.29 and 8.44±1.72, respectively) was significantly higher than at Dundee (3.4±0.30 and 7.76±1.63, respectively) and Harrismith (3.5±0.27 and 7.83±1.59, respectively) which were not different from one another. The mean HFIAS for Dundee (9.39±7.13) was significantly higher than that in Richards Bay (5.57±6.98) and Harrismith (6.43±6.59) which were not significantly different from one another. Dietary diversity scores were also significantly higher in urban locations than in peri-urban and rural ones whilst HFIAS was significantly lower in the urban locations than peri-urban and rural locations. There was lower dependence on food purchasing in Richards Bay compared to Dundee and Harrismith where the majority of the population was purchasing most of their food. The majority of Richards Bay households were involved in subsistence agriculture and also produced a surplus for sale, as well as collecting wild foods, which improved food security, unlike Dundee and Harrismith. Food insecurity was higher in rural and peri-urban areas compared to urban areas. In all towns, food was always available throughout the year but was beyond the reach of many households. In urban areas food was readily available and only limited by access, whereas rural populations have limited access to affordable food and face higher prices. The peri-urban populations were more food insecure because of high levels of poverty, unemployment and lack of access/entitlements to land. Periurban dwellers are therefore more sensitive to changes in incomes and food prices because they lack safety nets to absorb income or price shocks as they purchase more, rather than growing their own food. Household dietary diversity was significantly negatively correlated with household food access, that is households with low HDDS had higher HFIAS scores. Due to high levels of food insecurity, a greater percentage of children under the age of five years were stunted (35 %) and wasted (18 %). There were no significant differences in stunting along the agro-ecological gradient, along the rural-urban continuum and sex of child. However, significant differences were observed in child wasting along the agro-ecological gradient with Harrismith having more wasted children than the other two towns, which were not significantly different from each other. Significant differences were also observed between MUAC and sex of child where male children had higher MUAC than females. Wasting was significantly negatively associated with HDDS, with children from households with low HDDS tending to have large MUAC thus showing an inverse association among HDDS and obesity. However, further studies are needed to confirm this finding. In general food insecurity was closely associated with low wealth, food expenditure, large household size and limited access to land. The study did not find any significant role in the use of wild foods and social grants in improving food security for those households who were consuming wild foods and those receiving social grants. Although a greater percentage of households were food insecure, significant amounts of unprepared food (495±179 g per household) were wasted in Richards Bay alone in 48 hours mainly because the food had passed the best before date or had visibly gone bad. The amount of food waste was closely significantly negatively associated with household size. In general, the prevalence of food insecurity and wasting followed the agro-ecological gradient, with households in Richards Bay where the area.
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