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Editorial

  • Authors: Schudel, Ingrid J , Le Grange, Lesley , Reddy, Chris
  • Date: 2016
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/387193 , vital:68214 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/167508"
  • Description: The unprecedented levels of human influence on the global enviroment have drawn the attention of scientists to the extent that in 2002, the Nobel Laureate, Paul Crutzen, helped in postulating a new geological epoch named the Anthropocene (Crutzen, 2002). This idea is not new and Crutzen describes an observation by an Italian geologist named Antonio Stoppani who, in 1873, spoke about an 'anthropozoic era'. Stoppani described this era as a 'new telluric force which in power and universality may be compared to the greater forces of earth' (Stoppani, 1873 in Crutzen, 2002).
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  • Date Issued: 2016

Assessment of the long-term response to rehabilitation of two wetlands in KwaZulu-Natal, South Africa:

  • Authors: Cowden, Craig , Kotze, Donovan C , Ellery, William F N , Sieben, E J J
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/144431 , vital:38345 , DOI: 10.2989/16085914.2014.954518
  • Description: Assessing the ecological outcomes of wetland rehabilitation activities is an important need recognised by the ‘Working for Wetlands’ programme in South Africa. An assessment of ecological response was conducted in the Killarney and Kruisfontein wetlands, KwaZulu-Natal, in 2005 prior to rehabilitation in 2006, and again in 2011 and 2012, respectively, following rehabilitation. The assessment criteria included an evaluation of changes in ecological integrity, the supply of ecosystem services, and vegetation composition. Improvements in hydrological and geomorphic integrity were recorded in both wetlands, resulting in improved ecosystem delivery.
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  • Date Issued: 2014

Imagining Civil Society in Zimbabwe and ‘Most of the World’:

  • Authors: Helliker, Kirk D
  • Date: 2014
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/144802 , vital:38380 , ISBN 9781461482628 , DOI: 10.1007/978-1-4614-8262-8_11
  • Description: This chapter re-visits the notion of civil society in what Partha Chatterjee (The Politics of the Governed, 2004) calls ‘most of the world’ (beyond the capitalist metropoles) and, in doing so, uses Zimbabwe (and Africa more broadly) as an entry point into the literature on civil society. This chapter consists of four main sections. First, I discuss literature on civil society in Africa which, in the main, dichotomises civil society and the state empirically without any sustained theoretical reflections. Second, I provide an overview of Zimbabwean society and politics over the past decade and the ensuing debate, which in many ways produces a Manichean dualism whereby civil society is equated with progression and the state with regression. Third, I locate this conceptualisation of civil society within the broader international literature on civil society. These three sections, as a whole, highlight slippages in defining and understanding civil society: between civil society as a set of empirically identifiable organisational formations and civil society as a social space marked by civil liberties and voluntary arrangements in bourgeois society. Finally, I reimagine civil society in relation to ‘most of the world’.
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  • Date Issued: 2014

Incorporating surrogate species and seascape connectivity to improve marine conservation outcomes

  • Authors: Olds, Andrew D , Connolly, Rod M , Pitt, Kylie A , Maxwell, Paul S , Aswani, Shankar , Albert, Simon
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124722 , vital:35655 , https://doi.10.1111/cobi.12242
  • Description: Conservation focuses on maintaining biodiversity and ecosystem functioning, but gaps in our knowledge of species biology and ecological processes often impede progress. For this reason, focal species and habitats are used as surrogates for multispecies conservation, but species-based approaches are not widely adopted in marine ecosystems. Reserves in the Solomon Islands were designed on the basis of local ecological knowledge to conserve bumphead parrotfish (Bolbometopon muricatum) and to protect food security and ecosystem functioning. Bumphead parrotfish are an iconic threatened species and may be a useful surrogate for multispecies conservation. They move across tropical seascapes throughout their life history, in a pattern of habitat use that is shared with many other species. We examined their value as a conservation surrogate and assessed the importance of seascape connectivity (i.e., the physical connectedness of patches in the seascape) among reefs, mangroves, and seagrass to marine reserve performance. Reserves were designed for bumphead parrotfish, but also enhanced the abundance of other species. Integration of local ecological knowledge and seascape connectivity enhanced the abundance of 17 other harvested fish species in local reserves. This result has important implications for ecosystem functioning and local villagers because many of these species perform important ecological processes and provide the foundation for extensive subsistence fisheries. Our findings suggest greater success in maintaining and restoring marine ecosystems may be achieved when they are managed to conserve surrogate species and preserve functional seascape connections.
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  • Date Issued: 2014

Indigenous People’s Detection of Rapid Ecological Change

  • Authors: Lauer, Matthew , Aswani, Shankar
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/124811 , vital:35699 , https://doi.10.1111/cobi.12250
  • Description: When sudden catastrophic events occur, it becomes critical for coastal communities to detect and respond to environmental transformations because failure to do so may undermine overall ecosystem resilience and threaten people’s livelihoods. We therefore asked how capable of detecting rapid ecological change following massive environmental disruptions local, indigenous people are. We assessed the direction and periodicity of experimental learning of people in the Western Solomon Islands after a tsunami in 2007. We compared the results of marine science surveys with local ecological knowledge of the benthos across 3 affected villages and 3 periods before and after the tsunami. We sought to determine how people recognize biophysical changes in the environment before and after catastrophic events such as earthquakes and tsunamis and whether people have the ability to detect ecological changes over short time scales or need longer time scales to recognize changes. Indigenous people were able to detect changes in the benthos over time. Detection levels differed between marine science surveys and local ecological knowledge sources over time, but overall patterns of statistically significant detection of change were evident for various habitats. Our findings have implications for marine conservation, coastal management policies, and disaster-relief efforts because when people are able to detect ecological changes, this, in turn, affects how they exploit and manage their marine resources.
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  • Date Issued: 2014

Life-history characteristics of an age-validated established invasive African sharptooth catfish, Clarias gariepinus, population in a warm-temperate African impoundment

  • Authors: Wartenberg, Reece , Weyl, Olaf L F , Booth, Anthony J , Winker, A Henning
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/443542 , vital:74130 , https://hdl.handle.net/10520/EJC145790
  • Description: It has been suggested that the invasive, omnivorous Clarias garipienus is capable of rapid invasions and long-term persistence in recently inhabited freshwater systems. To test this hypothesis, the life history of the established, extralimital Darlington Dam (33°10'31"S, 25°09'13"E) population was investigated. By counting post-fluorescent mark increments on otoliths from 21 chemically tagged wild fish recaptured 244-537 days later, the deposition of growth zones, comprising alternating opaque and translucent bands, was validated as annual. Examination of sectioned otoliths from 175 fish revealed that the oldest fish, two males of 840 and 1074 mm total length (TL), were 25 years old - 10 years older than previously described for any C. gariepinus population. The oldest female was 885 mm TL and 21 years old. Length-at-age was subsequently described using the von Bertalanffy growth model. Combined-sex growth was best described as Lt = 931.7 ( 1 - exp(-0.15(t +2.43))) mm TL. Total mortality (Z) was calculated using catch curve analysis and the Chapman and Robson estimator to be 0.35/yr. The presence of specimens 15 years and older indicates that these fish established quickly and supports the finding that mortality rates are low, which, in turn, suggests likely long-term population persistence.
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  • Date Issued: 2014

Modelling annual evapotranspiration in a semi-arid, African savanna: functional convergence theory, MODIS LAI and the Penman–Monteith equation

  • Authors: Palmer, Anthony R , Weideman, Craig I , Finca, Andiswa , Everson, Colin S , Hanan, Niall P , Ellery, William F N
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/144387 , vital:38341 , DOI: 10.2989/10220119.2014.931305
  • Description: Accurately measuring evapotranspiration (ET) is essential if we are to derive reasonable estimates of production and water use for semi-arid savannas. Estimates of ET are also important in defining the health of an ecosystem and the quantity of water used by the vegetation when preparing a catchment-scale water balance. We derived ET0 from an automatic weather station 30 km west of Skukuza, Kruger National Park, South Africa using the Penman– Monteith equation, and then used the MODIS LAI to inform the model of canopy phenological dynamics. This result was compared with 173 days of ET measurements from the eddy covariance (ETec) system near Skukuza in 2007 as well as from the ET recorded by a large-aperture scintillometer at the same site in 2005. The model compared favourably with both sets of measured data and, when used independently of the eddy covariance data, ETMODIS predicted an annual ET of 378 mm in 2007 for the semi-arid savanna around the Skukuza flux site.
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  • Date Issued: 2014

Ocean warming affects the distribution and abundance of resident fishes by changing their reproductive scope

  • Authors: Potts, Warren M , Booth, Anthony J , Richardson, Timothy J , Sauer, Warwick H H
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/125352 , vital:35775 , https://doi.10.1007/s11160-013-9329-3
  • Description: With ocean warming predicted globally, one of the mechanisms driving distributional shifts and changes in the abundance of resident fishes is reproductive output. The relationship between sea surface temperature and the reproductive activity of a eurythermic, resident coastal species, blacktail seabream Diplodus sargus capensis, was examined in the ‘‘ocean warming’’ hotspot of the northern Benguela. Reproductive activity was found to be restricted to periods when the water temperature dropped below 20 _C. A metadata analysis conducted on the D. sargus sub-species complex similarly showed that reproductive activity was restricted to temperatures between 15 and 20 _C, regardless of the range in ambient water temperature. Based on these findings and using satellite derived SST information, we examined D. s. capensis’s total and seasonal ‘‘reproductive scope’’ that is defined as either the area suitable for spawning each year or the duration of its potential spawning season at a fixed geographical locality, respectively. Trends were examined over the last three decades. Reproductive scope by area was found to be shrinking at a rate of 7 % per decade in southern Angola and expanding at a rate of 6 % per decade in northern Namibia. Reproductive scope by season decreased by 1.05 months per decade in Namibe, southern Angola and increased by 0.76 months per decade in Hentiesbaai, northern Namibia. Changes in reproductive scope may be a driving mechanism of distributional shifts in resident fishes, although the rate of the shifts is likely to be slow. More importantly, changes in reproductive scope will not be uniform throughout fish distributions and will most likely result in heterogeneous variations in fish abundance.
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  • Date Issued: 2014

Ocean warming hotspots provide early warning laboratories for climate change impacts

  • Authors: Pecl, Gretta T , Hobday, Alistair J , Frusher, Stewart , Sauer, Warwick H H , Bates, Amanda E
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/125363 , vital:35776 , https://doi.10.1007/s11160-014-9355-9
  • Description: A growing literature describes a wide range of negative impacts of climate change on marine resources and the people and communities they support, including species range changes, changes in productivity of fisheries and declines in economic performance (Doney et al. 2012; Poloczanska et al. 2013). These impacts, many of which are projected to increase in future, are compounded by growing pressures on marine resources (Halpern et al. 2008; Maxwell et al. 2013). An estimated 260 million people are involved directly or indirectly in global marine fisheries (Teh and Sumaila 2013) with many of the resources for capture fisheries already fully (&57 % in 2009) or over exploited (30 %) (FAO 2012). Nevertheless, production of marine resources will need to increase to accommodate the demands of a growing population, and the impacts of climate change on food security will need to be minimised (FAO 2009). Identifying opportunities and threats, and developing adaptation options in response to climate change impacts in the marine realm, is essential for optimising the benefits that society can continue to derive from the goods and services provided by marine resources.
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  • Date Issued: 2014

Ocean warming, a rapid distributional shift, and the hybridization of a coastal fish species

  • Authors: Potts, Warren M , Henriques, Romina , Santos, Carmen V D , Munnik, Kate , Ansorge, Isabelle J , Dufois, Francois , Sauer, Warwick H H , Booth, Anthony J , Kirchner, Carola , Sauer, Warwick , Shaw, Paul W
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/125375 , vital:35777 , https://doi.10.1111/gcb.12612
  • Description: Despite increasing awareness of large-scale climate-driven distribution shifts in the marine environment, no study has linked rapid ocean warming to a shift in distribution and consequent hybridization of a marine fish species. This study describes rapid warming (0.8 °C per decade) in the coastal waters of the Angola-Benguela Frontal Zone over the last three decades and a concomitant shift by a temperature sensitive coastal fish species (Argyrosomus coronus) southward from Angola into Namibia. In this context, rapid shifts in distribution across Economic Exclusive Zones will complicate the management of fishes, particularly when there is a lack of congruence in the fisheries policy between nations. Evidence for recent hybridization between A. coronus and a congener, A. inodorus, indicate that the rapid shift in distribution of A. coronus has placed adults of the two species in contact during their spawning events. Ocean warming may therefore revert established species isolation mechanisms and alter the evolutionary history of fishes. While the consequences of the hybridization on the production of the resource remain unclear, this will most likely introduce additional layers of complexity to their management.
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  • Date Issued: 2014

Simple, illustrated medicines information improves ARV knowledge and patient self-efficacy in limited literacy South African HIV patients:

  • Authors: Dowse, Roslind , Barford, Kirsty-Lee , Browne, Sara H
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/156698 , vital:40039 , DOI: 10.1080/09540121.2014.931559
  • Description: Few studies have investigated antiretroviral (ARV) knowledge and self-efficacy in limited literacy patients. Using a randomized controlled study design, we investigated the influence of a simple pre-tested patient information leaflet (PIL) containing both text and illustrations on HIV- and ARV-related knowledge and on self-efficacy over six months in a limited literacy African population. The recruited patients were randomly allocated to either control (standard care) or intervention group (standard care plus illustrated PIL). HIV and medicines-related knowledge was evaluated with a 22-question test at baseline, one, three, and six months. Self-efficacy was assessed using a modified version of the HIV Treatment Adherence Self-Efficacy Scale.
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  • Date Issued: 2014

Xenophobia, sovereign power and the limits of citizenship:

  • Authors: Idahosa, Grace E , Vincent, Louise
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/141970 , vital:38020 , DOI: 10.1080/09744053.2014.914637
  • Description: African foreigners in South Africa have frequently been the targets of violent and discriminatory practices, which occur in the enabling context of negative discourses concerning African foreigners that circulate in various spheres of public life. This study is interested in one particular field of interaction between African foreigners and the South African state, namely the public health sector. Discriminatory and, sometimes, violent practices towards African foreigners on the part of South African citizens are widely documented. Less discussed are the ways in which these practices of violence and discrimination are in fact state practices. We show this with reference to the treatment of African foreigners in the public health sector. We refer to this prejudicial treatment as health-care Xenophobia which is made possible by a wider set of discourses related to citizenship and the rights accruing to citizens which suggest the ‘non-rights’ of the non-citizen.
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  • Date Issued: 2014

"Abject dictatorship of the flesh" : corporeality in the fiction of Patrick White

"Giving voice" to the bereaved : family grief and resilience after a child has died

  • Authors: Scheepers, Lucas Johannes
  • Date: 2013
  • Subjects: Bereavement -- Psychological aspects , Death -- Psychological aspects , Loss (Psychology) , Grief
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9977 , http://hdl.handle.net/10948/d1021096
  • Description: This study investigated family grief and resilience following a child’s death. Representing 23 families, 35 bereaved parents completed biographical questionnaires, the Family Hardiness Index, and the Family Attachment and Changeability Index 8. Significant positive correlations were found between family hardiness and family adaptation, and between parents’ age and family hardiness. Using grounded theory, interviews allowed for the formulation of categories including grief, continuing bonds, external support, religion, and family hardiness. The study reveals the need for exploring unique experiences of families bereaved by children’s deaths and identifies family hardiness as a potential resilience factor for this population
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  • Date Issued: 2013

"The wings of whipped butterflies" : trauma, silence and representation of the suffering child in selected contemporary African short fiction

  • Authors: Njovane, Thandokazi
  • Date: 2013
  • Subjects: Children in literature Psychic trauma in literature Short stories, African (English) -- 21st century
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2253 , http://hdl.handle.net/10962/d1004214
  • Description: This dissertation, which examines the literary representation of childhood trauma, is held together by three threads of inquiry. Firstly, I examine the stylistic devices through which three contemporary African writers – NoViolet Bulawayo, Uwem Akpan, and Mia Couto – engage with the subject of childhood trauma in five of their short stories: “Hitting Budapest”; “My Parents’ Bedroom” and “Fattening for Gabon”; and “The Day Mabata-bata Exploded” and “The Bird-Dreaming Baobab,” respectively. In each of these narratives, the use of ingén(u)s in the form of child narrators and/or focalisers instantiates a degree of structural irony, premised on the cognitive discrepancy between the protagonists’ perceptions and those of the implied reader. This structural irony then serves to underscore the reality that, though in a general sense the precise nature of traumatic experience cannot be directly communicated in language, this is exacerbated in the case of children, because children’s physical and psychological frameworks are underdeveloped. Consequently, children’s exposure to trauma and atrocity results in disruptions of both personal and communal notions of safety and security which are even more severe than those experienced by adults. Secondly, I analyse the political, cultural and economic factors which give rise to the traumatic incidents depicted in the stories, and the child characters’ interpretations and responses to these exigencies. Notions of subjectivity and intersubjectivity, identity and community, victimhood and survival, agency and disempowerment are discussed here in relation to the context of postcolonial Africa and the contemporary realities of chronic poverty, genocide, child-trafficking, the aftermath of civil war, and the legacies of colonialism and racism. Thirdly, this dissertation inspects the areas of congruence and divergence between trauma theory, literary scholarship on trauma narratives, and literary attempts to represent atrocity and trauma despite what is widely held to be the inadequacy of language – and therefore representation – to this task. There are certain differences between the three authors’ depictions of children’s experiences of trauma, despite the fact that the texts all grapple with the aporetic nature of trauma and the paradox of representing the unrepresentable. To this end, they utilise various strategies – temporal disjunctions and fragmentations, silences and lacunae, elements of the fantastical and surreal, magical realism, and instances of abjection and dissociation – to gesture towards the inexpressible, or that which is incommensurable with language. I argue that, ultimately, it is the endings of these stories which suggest the unrepresentable nature of trauma. Traumatic experience poses a challenge to representational conventions and, in its resistance, encourages a realisation that new ways of writing and speaking about trauma in the African continent, particularly with regards to children, are needed. , Adobe Acrobat 9.54 Paper Capture Plug-in
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  • Date Issued: 2013

"This horrid war" - the newly discovered diary of Captain James Primrose, 1851-53

  • Authors: Jackson, Caroline
  • Date: 2013
  • Subjects: Primrose, James Maurice, 1819-1892 -- Diaries
  • Type: Text
  • Identifier: http://hdl.handle.net/10962/24703 , vital:23262 , MS 20 063 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017.
  • Description: "This horrid war" - the newly discoverd diary of Captain James Primrose, 1851-53" - In: Quarterly bulletin of the National Library of South Africa, vol. 67, no. 2, April to June 2013.
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  • Date Issued: 2013

'Leaders like children playing with a grenade?' : an analysis of how the Arab Spring was received in South Africa

  • Authors: Gevers, Tristan Ronald
  • Date: 2013
  • Subjects: Arab Spring, 2010- Revolutions -- Theory Arab countries -- Social conditions -- 21st century South Africa -- Social condtions -- 21st century
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2846 , http://hdl.handle.net/10962/d1006031
  • Description: When the Arab Spring took place, it took the world by surprise and sparked renewed interest in the idea of revolution. With differing opinions on what caused such a revolutionary wave throughout the North African and Middle Eastern region, many began looking at their own countries, and South Africa was no different. A debate was sparked in South Africa, as to whether there would be a revolution or not. What I originally set out to accomplish is to find out which side of the debate would be correct through the philosophical context of revolutionary theory. Initially, we attempted to define and consider the history of revolutionary theory. We found that revolutionary theory has gone through four generation and that even finding a theoretically informed definition is difficult. Following this, we considered some social-psychological theories of revolution as well as theories of moral indignation. We found that these theories were incredibly informative and that they provide some insight into the reasoning for revolutionary fear in the South African debate. Through the use of opinion pieces, we then considered the South African debate, and – using socialpsychological theories and the theories of moral indignation - found that both sides of the argument had valuable points, however, they often lacked some foresight. With tentative agreement, we found that the side arguing that there would a revolution in South Africa had a more valuable argument, despite its limitations. However, far more research is required before one can – with more accuracy – predict a revolutionary occurrence in such a way as was done in South Africa.
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  • Date Issued: 2013

'The Area of a Triangle is 1800C’: an analysis of Learners' Idiosyncratic Geometry Responses through the Lenses of Vygotsky's Theory of Concept Formation

  • Authors: Mhlolo, Michael K , Schäfer, Marc
  • Date: 2013
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/141127 , vital:37946 , DOI: 10.1080/10288457.2013.826973
  • Description: In this paper, we focus specifically on Vygotsky's theory of concept formation to gain initial insights into seemingly garbled and incoherent connections we observed in learners' responses to a geometry task. While acknowledging research that is supportive of the van Hiele model as being useful when analysing concept formation in geometry, in this paper we use empirical evidence to argue that today's geometry requires learners to reason with many tools which the van Hiele model does not seem to accommodate. Working with 470 written responses of 12–14-year-old learners to a geometry task, we then explored the potential of Vygotsky's theory of concept formation as an alternative framework. We conclude by discussing the paper's contribution both to theory and to classroom practice.
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  • Date Issued: 2013

13C pulse-chase labeling comparative assessment of the active methanogenic archaeal community composition in the transgenic and nontransgenic parental rice rhizospheres

  • Authors: Zhu, Weijing , Lu, Haohao , Hill, Jaclyn M , Wang, Hailong , Wu, Weixiang
  • Date: 2013
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/122993 , vital:35389 , https://doi.org/10.1111/1574-6941.12261
  • Description: Rhabdosargus holubi (Steindachner, 1881) is a small (maximum size = 450 mm total length; Heemstra and Heemstra 2004) sparid that is distributed along the south-east coast of Africa from St Helena Bay, South Africa, to Maputo, Mozambique (Götz and Cowley 2013). Spawning occurs in the nearshore marine environment primarily during winter, specifically May–August in KwaZulu-Natal (KZN) (Wallace 1975) and July–February in the South-Eastern Cape (Whitfield 1998). Individuals reach 50% sexual maturity at approximately 150 mm standard length (SL) in the Eastern Cape (Whitfield 1998). The early life stages are transported by the south-westward-flowing Agulhas Current, and recruit as post-flexion larvae and early juveniles into estuaries during late winter and early summer (Blaber 1974). The warm temperatures and high nutrient levels in estuaries favour fast growth (Blaber 1973a), and fish spend their first year of life in these environments, migrating back out to sea after reaching approximately 120 mm SL. Some individuals remain trapped in closed estuaries, where they may reach sizes greater than 200 mm SL (James et al. 2007a). Rhabdosargus holubi is the dominant estuarine-dependent marine teleost species recorded in permanently open and temporarily open/closed estuaries in the warm-temperate region, which spans the south, south-east and east coast of South Africa (Harrison 2005). The species is also an important component of the linefishery in many SouthAfrican estuaries (10–15.6% by number) (Pradervand and Baird 2002), particularly in Eastern Cape estuaries (Cowley et al. 2003). These figures underestimate the presence of R. holubi, as most individuals making use of estuaries are young, feeding predominately on filamentous macroalgae and diatom flora, and are generally too small to be caught with hook and line (De Wet and Marais 1990). James et al. (2007b) showed that R. holubi made up 34–92% of the annual seine-net catch in the East Kleinemonde Estuary. Rhabdosargus holubi is also important in the KZN shorebased linefishery, representing 4.6% of the total landed catch (Dunlop and Mann 2012)More and more investigations indicate that genetic modification has no significant or persistent effects on microbial community composition in the rice rhizosphere. Very few studies, however, have focused on its impact on functional microorganisms. This study completed a 13C-CO2 pulse-chase labeling experiment comparing the potential effects of cry1Ab gene transformation on 13C tissue distribution and rhizosphere methanogenic archaeal community composition with its parental rice variety (Ck) and a distant parental rice variety (Dp). Results showed that 13C partitioning in aboveground biomass (mainly in stems) and roots of Dp was significantly lower than that of Ck. However, there were no significant differences in 13C partitioning between the Bt transgenic rice line (Bt) and Ck. RNA-stable isotope probing combined with clone library analyses inferred that the group Methanosaetaceae was the predominant methanogenic Archaea in all three rice rhizospheres. The active methanogenic archaeal community in the Bt rhizosphere was dominated by Methanosarcinaceae, Methanosaetaceae, and Methanomicrobiaceae, while there were only two main methanogenic clusters (Methanosaetaceae and Methanomicrobiaceae) in the Ck and Dp rhizospheres. These results indicate that the insertion of cry1Ab gene into the rice genome has the potential to result in the modification of methanogenic community composition in its rhizosphere.
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  • Date Issued: 2013

1H NMR-based kinetic-mechanistic study of the intramolecular trans-esterification of 2-exo-3-exo-dihydroxybornane monoacrylate esters

  • Authors: Duggan, Andrew R , Mciteka, Lulama P , Lobb, Kevin A , Kaye, Perry T
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/448871 , vital:74767 , xlink:href="https://hdl.handle.net/10520/EJC135616"
  • Description: A 1H NMR study of the acid-catalyzed, intramolecular trans-esterification between isomeric 2-exo-3-exo-dihydroxybornane monoacrylate esters has afforded insights into the reaction mechanism and permitted the determination of kinetic and thermodynamic parameters for the pseudo-first-order processes.
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  • Date Issued: 2013
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