List of Titles

Specialty Grand Challenges in Urban Agriculture: Ecological and Social Approaches to Sustainability Transformations

- Zimmerer, Karl S, Bell, Martha G, Chirisa, Innocent, Duvall, Chris S, Egerer, Monika, Hung, Po-Yi, Lerner, Amy M, Shackleton, Charlie M, Ward, James David, Yacamán Ochoa, Carolina

Authors: Zimmerer, Karl S , Bell, Martha G , Chirisa, Innocent , Duvall, Chris S , Egerer, Monika , Hung, Po-Yi , Lerner, Amy M , Shackleton, Charlie M , Ward, James David , Yacamán Ochoa, Carolina
Date: 2021
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/175779 , vital:42623 , https://doi.org/10.3389/fsufs.2021.668561
Description: This synopsis of the Grand Challenges of Urban Agriculture (UA) is framed by the urgent need to understand and strengthen the expanding yet highly diverse roles of UA amid rapid global urbanization, failures of predominant food systems, and crises in systems of physical and mental health. More than half of humanity lives in cities today and by 2030 this is projected to grow to 60.4 percent, ~5 billion people (UN Habitat, 2020). More than 90 percent of urban demographic increase is anticipated to take place in the developing world.
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Date Issued: 2021

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Preliminary evidence for the organisation of a bacterial community by zooplanktivores at the top of an estuarine planktonic food web

- Wasserman, Ryan J, Matcher, Gwynneth F, Vink, Tim J F, Froneman, P William

Authors: Wasserman, Ryan J , Matcher, Gwynneth F , Vink, Tim J F , Froneman, P William
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/68237 , vital:29222 , https://doi.org/10.1007/s00248-014-0505-3
Description: Publisher version , As part of a larger investigation, the effect of apex predation on estuarine bacterial community structure, through trophic cascading, was investigated using experimental in situ mesocosms. Through either the removal (filtration) or addition of specific size classes of planktonic groups, four different trophic scenarios were established using estuarine water and its associated plankton. One such treatment represented a “natural” scenario in which stable apex predatory pressure was qualified. Water samples were collected over time from each of the treatments for bacterial community evaluation. These samples were assessed through pyrosequencing of the variable regions 4 and 5 of the bacterial 16S rRNA gene and analysed at the species operational taxonomic unit (OTU) level using a community procedure. The blue-green group dominated the samples, followed by Proteobacteria and Bacteroidetes. Samples were the most similar among treatments at the commencement of the experiment. While the bacterial communities sampled within each treatment changed over time, the deviation from initial appeared to be linked to the treatment trophic scenarios. The least temporal deviation-from-initial in bacterial community was found within the stable apex predatory pressure treatment. These findings are consistent with trophic cascade theory, whereby predators mediate interactions at multiple lower trophic levels with consequent repercussions for diversity.
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Date Issued: 2015

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Bloodmeal analysis in Culicoides midges collected near horses, donkeys and zebras in the Eastern Cape, South Africa:

- Riddin, M A, Venter, G J, Labuschagne, K, Villet, Martin H

Authors: Riddin, M A , Venter, G J , Labuschagne, K , Villet, Martin H
Date: 2019
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/140692 , vital:37910 , DOI: 10.1111/mve.12381
Description: An upsurge in African horse sickness (AHS) in the Eastern Cape, South Africa, from 2006 led to an epidemiological reassessment of the disease there. Light trapping surveys carried out near horses, donkeys and zebras in 2014–2016 collected 39 species of Culicoides midge (Diptera: Ceratopogonidae) that are potential vectors of AHS. To establish if these midges fed on equids, DNA sequences were obtained from the gut contents of 52 female midges (35 freshly blood-fed, 13 gravid and four parous), representing 11 species collected across 11 sites. Culicoides leucostictus fed on all three equids. Culicoides bolitinos, Culicoides imicola and Culicoides magnus fed on both horses and donkeys. Culicoides onderstepoortensis fed on donkeys, and Culicoides similis and Culicoides pycnostictus fed on zebras. Bloodmeals from cows, pigs, warthogs, impalas and a domestic dog were also identified in various species, but none of the midges tested had fed on birds. These results contribute to knowledge of the vectorial capacity of several species of Culicoides with regard to AHS in the Eastern Cape and point to potential reservoir hosts, of which donkeys, zebras and domestic dogs have previously been found to harbour AHS. Blood-fed midges were also obtained throughout winter, indicating the potential for endemic AHS in the province.
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Date Issued: 2019

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Fabrication of dye-sensitized solar cells based on push-pull asymmetrical substituted zinc and copper phthalocyanines and reduced graphene oxide nanosheet:

- Chindeka, Francis, Mashazi, Philani N, Britton, Jonathan, Oluwole, David O, Mapukata, Sivuyisiwe, Nyokong, Tebello

Authors: Chindeka, Francis , Mashazi, Philani N , Britton, Jonathan , Oluwole, David O , Mapukata, Sivuyisiwe , Nyokong, Tebello
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/149076 , vital:38802 , https://doi.org/10.1016/j.jphotochem.2020.112612
Description: Dye sensitized solar cells (DSSCs) were fabricated by using 2(3,5-biscarboxyphenoxy), 9(10), 16(17), 23(24)-tri(tertbutyl) phthalocyaninato Cu (4) and Zn (5) complexes as dyes on the ITO-TiO2 photoanodes containing reduced graphene oxide nanosheets (rGONS) or nitrogen-doped rGONS (NrGONS). The evaluation of the assembled DSSCs revealed that using ITO-TiO2-NrGONS-CuPc photoanode had the highest fill factor (FF) and power conversion efficiency (ɳ) of 69% and 4.36% respectively. These results show that the asymmetrical phthalocyanine complexes (4) and (5) exhibit significant improvement on the performance of the DSSC compared to our previous work on symmetrical carboxylated phthalocyanines with ɳ = 3.19%.
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Date Issued: 2020

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Social capital reduces vulnerability in rural coastal communities of Solomon Islands:

- Malherbe, Willem, Sauer, Warwick H H, Aswani, Shankar

Authors: Malherbe, Willem , Sauer, Warwick H H , Aswani, Shankar
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/150230 , vital:38951 , https://doi.org/10.1016/j.ocecoaman.2020.105186
Description: Rural island communities are generally regarded as the most vulnerable groups affected by climate change. This perception arises due to them often being in less developed areas with high levels of exposure to stressors, while reportedly lacking the means to cope with these stressors. Studies which use developed-country yardsticks, such as those used in past IPCC-based assessments, when measuring vulnerability in less developed states will however inevitably over-pronounce its effects in such areas. The sustainable livelihoods approach provides an alternate means of determining vulnerability using capital assets such as social capital. The presence of these assets enables communities to pursue diverse livelihood strategies which ultimately serve to reduce their vulnerability. This study seeks to measure attributes of social capital in five marine dependent communities of Solomon Islands.
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Date Issued: 2020

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Knowledge and knowledge sources on the importance of fruits for nutritional security are unaffected by deforestation status in Cameroon

- Ijang, T N P, Shackleton, Charlie M, Degrande, A

Authors: Ijang, T N P , Shackleton, Charlie M , Degrande, A
Date: 2019
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/177454 , vital:42823 , DOI: 10.17660/th2019/74.6.2
Description: The Congo basin forest is experiencing increasing rate of deforestation, and is prone to inconsistent food supply and sporadic food shortages with corresponding high levels of malnutrition. Maintenance or planting of fruit trees can help mitigate deforestation while supplying fruits for home consumption. However, data on rates of fruit consumption are lacking for many developing countries, including Cameroon.
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Date Issued: 2019

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6th National Congress Resolutions

- Paper, Printing, Wood and Allied Workers' Union (PPWAWU)

Authors: Paper, Printing, Wood and Allied Workers' Union (PPWAWU)
Date: Oct 1993
Subjects: PPWAWU
Language: English
Type: text
Identifier: http://hdl.handle.net/10962/134779 , vital:37204
Description: Congress understood well what Cde Nqakula was saying and how important it is to mobilise all our forces to come in with a huge ANC majority in the elections. Delegates made sure through a strong resolution on elections that PPWAWU will play its part: the union will send a fulltime PPWAWU person to COSATU for voter education. This person is Sipho Kubheka and he is already at COSATU head office. One shopsteward from each region will also be released to assist COSATU. Branches must run voter education workshops at once with the education co-ordinator's help. Shopstewards must get time off to train as voter educators, and all workers must give R1 towards voter education.
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Date Issued: Oct 1993

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Do indigenous street trees promote more biodiversity than alien ones? evidence using mistletoes and birds in South Africa

- Shackleton, Charlie M

Authors: Shackleton, Charlie M
Date: 2016
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/64663 , vital:28587 , http://www.doi:10.3390/f7070134
Description: Trees in urban landscapes provide a range of ecosystem services, including habitat, refugia,food, and corridors for other fauna and flora. However, there is some debate whether the richness and abundance of other biodiversity supported is influenced by the provenance of trees, i.e., native or non-native. This study assessed the presence of mistletoes and birds (and nests) in 1261 street trees. There were marked differences between native and non-native street trees, with the former having a significantly higher prevalence of birds (and nests) and supporting more species and in greater densities, whilst the latter supported a higher prevalence of mistletoes. Additionally, for birds, the proximity to green space, tree size and species were also important, whilst for mistletoes, the proximity to green space, slope aspect, and tree species were significant. Preference ratios indicated that some tree species had a higher than random occurrence of birds or mistletoes, whilst others had a low abundance. The indigenous tree species, Acacia karroo Hayne was the only reasonably abundant street tree species that was important for birds, nests, and mistletoes. At the street scale, there was a positive relationship between street tree species richness and bird species richness. These results emphasise the importance of selecting appropriate tree species if biodiversity conservation is a core outcome.
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Date Issued: 2016

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An analysis of the influence of question design on learners' approaches to number pattern generalisation tasks:

- Samson, Duncan, Schäfer, Marc

Authors: Samson, Duncan , Schäfer, Marc
Date: 2007
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/141026 , vital:37938 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC20890
Description: This paper reports on a study of the extent to which question design affects the solution strategies adopted by children when solving linear number pattern generalisation tasks presented in pictorial and numeric contexts. The research tool comprised a series of 22 pencil-and-paper exercises based on linear generalisation tasks set in both numeric and two-dimensional pictorial contexts. The responses to these linear generalisation questions were classified by means of stage descriptors as well as stage modifiers. The method or strategy adopted was analysed and classified into one of seven categories. In addition, a meta-analysis focused on the formula derived for the nth term in conjunction with its justification. The results of this study strongly support the notion that question design can play a critical role in influencing learners' choice of strategy and level of attainment when solving pattern generalisation tasks. An understanding of the importance of appropriate question design has direct pedagogical application within the context of the mathematics classroom.
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Date Issued: 2007

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Integrating Climate Change Adaptation (CCA) and Disaster Risk Reduction (DRR) for greater local level resilience: lessons from a multi-stakeholder think-tank

- Pereira, Taryn, Shackleton, Sheona E, Donkor, Felix Kwabena

Authors: Pereira, Taryn , Shackleton, Sheona E , Donkor, Felix Kwabena
Date: 2017
Subjects: Climatic changes -- South Africa , Climatic changes -- South Africa -- Eastern Cape -- South Africa
Language: English
Type: text
Identifier: http://hdl.handle.net/10962/62027 , vital:28097
Description: The last few years have seen one of the most severe droughts in recent times in the southern African region, and news headlines are increasingly full of warnings about heavy storms, fires and floods. There is no doubt that extreme hydro-meteorological events, and their multiple and potentially disastrous impacts, are at the forefront of the public consciousness at the present time and are one of the key concerns regarding the impacts of climate change in the region. While the links between extreme climate events, disaster risk reduction (DRR - see Box 1) and climate change adaptation (CCA - see Box 2) are recognised in the South African Climate Change White Paper, this is not the case for the whole region. Furthermore, even if there is national recognition of the need to synergise these two spheres of endeavour, this does not always trickle down to effective policy, planning and implementation at the local level.
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Date Issued: 2017

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Biogeographical comparison of the emergent macrophyte, Sagittaria platyphylla in its native and introduced ranges

- Kwong, Raelene M, Sagliocco, Jean Louis, Harms, Nathan E, Butler, Kym L, Green, Peter T, Martin, Grant D

Authors: Kwong, Raelene M , Sagliocco, Jean Louis , Harms, Nathan E , Butler, Kym L , Green, Peter T , Martin, Grant D
Date: 2017
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/76980 , vital:30652 , https://doi.org/10.1016/j.aquabot.2017.05.001
Description: Understanding why some plant species become invasive is important to predict and prevent future weed threats and identify appropriate management strategies. Many hypotheses have been proposed to explain why plants become invasive, yet few studies have quantitatively compared plant and population parameters between native and introduced range populations to gain an objective perspective on the causes of plant invasion. The present study uses a biogeographical field survey to compare morphological and reproductive traits and abundance between the native range (USA) and two introduced ranges (Australia and South Africa) of Sagittaria platyphylla (Engelm.) J.G. Sm (Alismataceae), a highly invasive freshwater macrophyte. Introduced and native populations differed in sexual reproductive output with the number of achenes per fruiting head and individual achene weight found to be 40% and 50% greater in introduced populations respectively. However, no other morphological traits were found to be consistently different between the native and both introduced ranges, especially after taking into account differences in environmental conditions between the three ranges. Although populations in introduced regions were larger and occupied greater percentage cover, no differences in plant density were evident. Our results suggest that, apart from sexual reproduction, many of the trait patterns observed in S. platyphylla are influenced by environmental and habitat conditions within the native and invaded ranges. We conclude that the enemy release hypothesis best explains the results observed for sexual reproduction. In particular, we hypothesise that a release from natural enemies, specifically a pre-dispersal seed predator, may induce reproductive plasticity in S. platyphylla.
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Date Issued: 2017

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Towards empowering learners in a democratic mathematics classroom: to what extent are teachers' listening orientations conducive to and respectful of learners' thinking?

- Mhlolo, Michael K, Schäfer, Marc

Authors: Mhlolo, Michael K , Schäfer, Marc
Date: 2012
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/140882 , vital:37926 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC129235
Description: In an effort to make education accessible, to 'heal the divisions of the past and establish a society based on democratic values', the South African Department of Education claims that a series of mathematics reforms that has so far been introduced is underpinned by the principles of 'social justice, fundamental human rights and inclusivity'. Critics however argue that the system has remained 'undemocratic' in that those groups of learners who were supposed to be 'healed' continue to underperform and hence be disempowered. In this study, we conceptualised a democratic and mathematically empowering classroom as one that is consistent with the principle of inclusivity and in which a hermeneutic listening orientation towards teaching promotes such a democratic and mathematically empowering learning environment. We then worked with three different orientations teachers might have towards listening in the mathematics classroom: evaluative, interpretive and hermeneutic. We then used these orientations to analyse 20 video-recorded lessons with a specific focus on learners' unexpected contributions and how teachers listened and responded to such contributions. The results were consistent with the literature, which shows that teachers tend to dismiss learners' ways of thinking by imposing their own formalised constructions.
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Date Issued: 2012

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Factors affecting recapture rates of raggedtooth sharks Carcharias taurus tagged off the east coast of South Africa

- Dicken, Matthew L, Booth, Anthony J, Smale, Malcolm J

Authors: Dicken, Matthew L , Booth, Anthony J , Smale, Malcolm J
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/124493 , vital:35618 , https://doi.10.2989/AJMS.2009.31.3.9.997
Description: Understanding differences in the recapture rate between different tags (A-, B- and C-types), capture methods (rock-and-surf anglers, scientific divers and Natal Sharks Board protection nets) and life-history stages (juvenile and adult) is critical in evaluating the results obtained from cooperative tagging programmes (CTPs). A generalised linear modelling approach, using a log-linear model, was used to determine significant differences in the probability of recapture between these various factors using data from the Oceanographic Research Institute and Port Elizabeth Museum CTPs. Between 1984 and 2004, a total of 3 385 raggedtooth sharks Carcharias taurus was tagged by volunteers from both programmes along the east coast of South Africa. A likelihood ratio test indicated significant differences in the probability of recapture between A- and C-type and B- and C-type tags (p < 0.01), between different capture methods (p < 0.05) and between juvenile and adult sharks (p < 0.01). A comparison of recapture rates between members of the CTPs also indicated a marked variability in the performance of individual taggers. The study highlights important data-quality issues inherent in large CTPs.
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Date Issued: 2010

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Development of manganese phthalocyanine decorated with silver nanoparticles nanocomposite for improved electrocatalytic oxidation of hydrazine:

- Mpeta, Lekhetho S, Sen, Pinar, Nyokong, Tebello

Authors: Mpeta, Lekhetho S , Sen, Pinar , Nyokong, Tebello
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/148472 , vital:38742 , https://doi.org/10.1016/j.jelechem.2020.114173
Description: In this study we report on the synthesis of tetrakis [4-(4-(5-chloro-1H-benzo [d]imidazol-2-yl) phenoxy phthalocyaninato] manganese (III) chloride (MnPc). The MnPc was first used to modify a glassy carbon electrode, followed by the growth of silver nanoparticles (AgNPs) onto the MnPc modified electrode to form MnPc-AgNPs modified electrode. The modified electrode was characterized using cydic voltammetry, chronoamperometry, scanning electrochemical microscopy and electrochemical impedance spectroscopy. The modified MnPc-AgNPs electrode was employed for the detection of hydrazine. The MnPc-AgNPs gave better current responses for electrooxidation of hydrazine relative to MnPc and AgNPs, individually. The catalytic rate constant was 1.90 x 10(5 )M(-1) S-1, with the detection limit (LoD) of 2.42 pM (using 3 sigma notation), and sensitivity of 61.56 mu A mM(-1), for MnPc-AgNPs. (C) 2020 Elsevier B.V. All rights reserved.
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Date Issued: 2020

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Local institutions, actors, and natural resource governance in Kgalagadi Transfrontier Park and surrounds, South Africa

- Thondhlana, Gladman, Shackleton, Sheona E, Blignaut, James

Authors: Thondhlana, Gladman , Shackleton, Sheona E , Blignaut, James
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/67689 , vital:29130 , https://doi.org/10.1016/j.landusepol.2015.03.013
Description: Publisher version , Crafting local institutions to allow more effective decision-making in the management of and access to natural resources in and beyond parks has long been considered key to collaborative governance. South Africa, in particular, has vigorously pursued collaborative governance as a desired approach to managing natural resources as evident in the new arrangements for previously restricted parks. However, though the discourse of collaborative governance has occupied conservation thinking and practice globally, few studies have looked at the interplay between local institutions, actors and collaborative governance involving indigenous hunter–gatherer communities in Southern Africa. In response, we assess the local actors and institutions that were put in place to facilitate collaborative governance of natural resources in the Kgalagadi Transfrontier Park and its surrounds in South Africa. Our findings show that though collaborative governance has a practical appeal, it is hampered by lack of participation in decision-making, information dissemination, transparency, trust and accountability, power relations, divergent interests and unequal access to natural resources. The findings also draw our attention to issues of heterogeneity, even within indigenous communities assumed to be homogenous by local conservation authorities as reflected in land settlement agreements in co-managed parks. We argue that collaborative governance arrangements need to reflect and be understood within the broader background of complex local realities.
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Date Issued: 2015

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