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Invasive alien species as drivers in socio-ecological systems: Local adaptations towards use of Lantana in Southern India

  • Authors: Kannan, Ramesh , Shackleton, Charlie M , Shaanker, Ramanan U
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/180932 , vital:43671 , xlink:href="https://doi.org/10.1007/s10668-013-9500-y"
  • Description: Lantana camara. L (hereafter Lantana) was first introduced by the British into India in 1807 as an ornamental plant. Since then the species has spread across the length and breadth of the country. Attempts to control Lantana in India have not been successful. In this study, we analysed the use of Lantana by local communities in southern India and identified the possible causes and consequences of its use through the use of a household survey of the socio-economic profile of the user and nonuser households and an analysis of the ecological history of the communities. Communities have been using Lantana for over 25–30 years and apparently such use was not prompted by external agencies. The characteristics of user and nonuser households were similar, except that Lantana users were more literate and had a greater number of occupations per household than nonusers. Per capita income was similar between user and nonuser groups. For nonuser groups, their main income sources were from trading (44 %), wage labour (32 %) and forest resources (23 %). In contrast, the Lantana user groups substituted their loss of income from forest resources (7 %) by income from Lantana (46 %). The ecological history revealed that Lantana was adopted as a resource at a time when it was increasing in the landscape and traditional bamboo resources were in decline because of overuse by commercial enterprises and mast flowering. This change in ecological resource availability prompted a major shift in livelihoods for some in the area.
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  • Date Issued: 2014

Investigating coral reef ethnobiology in the western Solomon Islands for enhancing livelihood resilience:

  • Authors: Aswani, Shankar
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/145425 , vital:38437 , DOI: 10.15286/jps.123.3.237-276
  • Description: Coral reefs are of great socio-economic and cultural importance for many coastal communities across the tropics, yet little is known about people's local classifications and their social and ecological relationships with these habitats. In the case of island peoples, coral reefs are more than just resource exploitation areas; they are also géomorphologie features that allow or bar people from navigating, markers that define property rights of the seascape in relation to other coastal and terrestrial habitats, and cultural and historical features that embody tribal identity and ideology. Building upon over two decades of research, this paper uses published and unpublished data to describe people's ecological and socio-economic relationships with coral reefs in two extensive lagoon ecosystems in the Western Solomon Islands.
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  • Date Issued: 2014

Investigating the chaperone properties of a novel heat shock protein, Hsp70. c, from Trypanosoma brucei

  • Authors: Burger, Adélle , Ludewig, Michael H , Boshoff, Aileen
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/431155 , vital:72749 , xlink:href="https://doi.org/10.1155/2014/172582"
  • Description: The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70) is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif.The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated.The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c.In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.
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  • Date Issued: 2014

Investigation of the Chemical Nature and Species Distribution of Nitromethane in Inert Solvents

  • Authors: Namntu, Vuyokozi
  • Date: 2014
  • Language: English
  • Type: Masters theses , text
  • Identifier: http://hdl.handle.net/11260/2964 , vital:43106
  • Description: The solution behaviour of nitromethane in inert solvents; carbon tetrachloride, n-hexane and cyclohexane is rigorously investigated using mainly spectroscopic and computational techniques. Analysis of Proton (1H) and Carbon 13 (13C) NMR spectral data reveal that nitromethane solutions in inert solvents form associated species to varying degrees of complexity. A cyclic dimer is postulated as the energetically most favourable chemical species at low solute concentrations. Infrared spectra studied in the overtone region and UV-Visible spectral data confirm the presence of multiple associated chemical species at different solute concentrations with the degree of association progressively increasing with increase in concentration of the solute. The species involved in the association of nitromethane is formulated as (CH3NO2)2n, where n=0, 1,2 and 3, for the monomer, dimer and higher order polymers respectively. Line-shape analysis of both infrared and UV spectra show the onset of a plateau at molar solute concentrations of 0.616 molar described by the point of inflection in the absorption curve at around 0.055 cm-1 , in the second overtone. , Thesis (MSc) -- Faculty of Natural Sciences, 2014
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  • Date Issued: 2014

Investigations of growth metrics and δ15N values of water hyacinth (Eichhornia crassipes,(Mart.) Solms-Laub) in relation to biological control

  • Authors: Hill, Jaclyn M
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/444758 , vital:74265 , https://doi.org/10.1016/j.aquabot.2013.12.001
  • Description: The success of biological control for Eichhornia crassipes (Mart) Solms-Laub has been varied, with failure attributed to various factors including increased eutrophication in freshwater systems. Studies have shown that high N-loads are associated with enriched δ15N values of aquatic biota. Stable isotope analyses may help to assess the nutrient status of invaded ecosystems and predict the success of classical biological control. A combination of controlled greenhouse experiments and in situ observations were used to quantify the δ15N equilibration rate of E. crassipes leaf tissue (i.e. the time span of the information on environmental N-loading), confirm the ability of plant tissue to reflect ecosystem N-loading and to compare standard water hyacinth growth metrics with δ15N and C/N ratios to evaluate how well they described eutrophication. Using both δ15N values and C/N ratios, it was possible to clearly distinguish between manure, fertilizer and control regimes and plant tissue provided information on ecosystem N loading over approximately 16 days.
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  • Date Issued: 2014

Isn’t it time to start thinking about ‘developing’ academic developers in a more systematic way?

  • Authors: Quinn, Lynn , Vorster, Jo-Anne E
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/66546 , vital:28961 , https://doi.org/10.1080/1360144X.2013.879719
  • Description: publisher version , There is no defined route to becoming an academic developer. The research on pathways into the field (e.g. Kensington-Miller, Brailsford, and Gossman, 2012; McDonald, 2010; McDonald and Stockley, 2008) shows that in most cases ‘serendipity and chance played a role’ (McDonald, 2010, p. 40). Moreover, induction into academic development (AD) is often ad hoc, haphazard, and informal. Due to the changing higher education (HE) context, the field has grown exponentially and in many countries now plays a central role in institutions. This has generated increased demand for knowledgeable and competent developers that are able to contribute towards solving some vexing problems in contemporary HE. Current recruitment and induction processes of new developers do not necessarily meet this demand. In light of the above, we pose the question: given the changing context of HE and the field of AD, is it not time for us to induct newcomers into the field more systematically? As Kensington-Miller et al. (2012) suggest, we should not leave the induction of the next generation of developers to chance. We suggest that one way of ensuring appropriate induction is through a formal course for developers. Difficulties for newcomers to the field are illustrated by Kensington-Miller et al. (2012) when they report seeking ‘top tips’ at a HERDSA conference. We do not dismiss informal learning at conferences or the role of mentoring, coaching, apprenticeship, and so on, in inducting developers, nor do we minimise the benefits of relatively structured processes such as fellowship programmes, workshops, and postgraduate qualifications in related fields. However, these ways of induction may not offer novices the structured and systematic developmental opportunities needed to become developers able to fulfil varied, complex, and sometimes contradictory roles.
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  • Date Issued: 2014

ISSRs indicate that Chromolaena odorata invading southern Africa originates in Jamaica or Cuba

  • Authors: Paterson, Iain D , Zachariades, Costas
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/406105 , vital:70239 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.04.005"
  • Description: Two biotypes of the invasive alien plant, Chromolaena odorata (L.) R.M. King and Rob. (Asteraceae: Eupatorieae), are recognized in the plant’s introduced distribution. The Asian/West African (A/WA) biotype is present in West and Central Africa, India, Southeast Asia and Oceania, while the southern African (SA) biotype is only present in southern Africa. Biological control using insect natural enemies has been significantly more successful against the A/WA biotype than the SA biotype, suggesting that host plant incompatibility may have resulted in reduced efficacy of biological control agents in southern Africa. Inter-Simple Sequence Repeats (ISSR) were used to identify the origin of the SA biotype as Jamaica or Cuba. The data also confirm that the SA biotype is genetically distinct from the A/WA biotype and that the SA biotype is the result of a separate introduction. Biological control agents for C. odorata in southern Africa should be sourced from Jamaica and Cuba in order to avoid host plant incompatibility problems.
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  • Date Issued: 2014

Kalaharituber pfeilii and associated bacterial interactions

  • Authors: Adeleke, Rasheed , Dames, Joanna F
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/440490 , vital:73787 , https://doi.org/10.1016/j.sajb.2013.10.003
  • Description: Truffles are generally known to form a mycorrhizal relationship with plants. Kalaharituber pfeilii (Hennings) Trappe and Kagan-Zur is a species of desert truffle that is found in the southern part of Africa. The life cycle of this truffle has not been fully investigated as there are many unconfirmed plant species that have been suggested as potential hosts. Many mycorrhizal associations often involve other role players such as associated bacteria that may influence the establishment of the mycorrhizal formation and function. As part of an effort to understand the life cycle of K. pfeilii, laboratory experiments were conducted to investigate the role of ascocarp associated bacteria. Bacterial isolates obtained from the truffle ascocarps were subjected to microbiological and biochemical tests to determine their potentials as mycorrhizal helper bacteria. Tests conducted included stimulation of mycelial growth in vitro, indole acetic acid (IAA) production and phosphate solubilising. A total of 17 bacterial strains belonging to the Proteobacteria, Firmicutes and Actinobacteria were isolated from the truffle ascocarps and identified with sequence homology and phylogenetic methods. Three of these isolates showed potential to be helper bacteria in at least one of the media tested through the stimulation of mycelial growth. Furthermore, four isolates produced IAA and one was able to solubilise CaHPO3 in vitro. One isolate, identified as a relative of Paenibacillus sp. stimulated mycelial growth on all the media tested. Other bacterial isolates that showed potential stimulation of mycelial growth were identified molecularly as a Bacillus sp. and two strains of Rhizobium sp. This study has contributed to the existing knowledge on the biotic interactions with K. pfeilii which may be useful in further symbiont and re-synthesis investigations.
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  • Date Issued: 2014

Leadership for biodiversity in South Africa transformation and capacity development in the GreenMatter programme

  • Authors: Rosenberg, Eureta
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , book chapter
  • Identifier: http://hdl.handle.net/10962/437190 , vital:73351 , ISBN 978-9086862528 , https://doi.org/10.3920/978-90-8686-802-5_18
  • Description: As we begin to write this chapter, it is only a few hours since the news broke about the passing of Nelson Mandela, the founding president of a democratic South Africa. As we de-scribe our work in supporting intergenerational learning and the development of transformational leadership, it seems appro-priate to make this reference as a tribute to him. This work would not have been possible without the contribution of Man-dela and all who fought for justice and an egalitarian society in South Africa. We are able to write about the so-called ‘born frees’ because of Mandela’s role in dismantling apartheid, a system that sought to condemn black people to perpetual ser-vitude, ignorance and poverty. Indeed, our efforts in building skills for biodiversity, under the auspices of GreenMatter, are inspired by his courageous leadership, his selflessness, com-mitment to education and love of people, knowledge and na-ture. While philosophies, contexts and methods will vary, the quest of all intergenerational learning is to build a bridge that enables young people to learn from the experiences and wisdom of previous generations.
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  • Date Issued: 2014

Lever Brothers & Unilever – a practical problem of source?

Liberation movements in power: party and state in southern Africa

  • Authors: Helliker, Kirk D
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/144688 , vital:38370 , DOI: 10.1080/21528586.2014.960705
  • Description: In Liberation movements in power, Roger Southall provides a rich and refined account of political transformation in three ex-settler colonies in southern Africa, namely, South Africa, Namibia and Zimbabwe. In particular, he focuses on their former hegemonic national liberation movements, namely, the African National Congress (ANC) in South Africa, the South West African People’s Organisation (SWAPO) in Namibia and the Zimbabwe African National Union (ZANU) – now ZANU-Patriotic Front (ZANU-PF) – in Zimbabwe, their metamorphism into political parties and party machines, and their ‘capture’ of state power as the dominant political party subsequent to the end of white settler colonialism and the emergence of non-racial democracy. The general conclusion is that democratic ideals and procedures have become subordinated to the dictates of authoritarian restructuring.
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  • Date Issued: 2014

Life satisfaction and education in South Africa: Investigating the role of attainment and the likelihood of education as a positional good

  • Authors: Botha, Ferdi
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/396091 , vital:69149 , xlink:href="https://doi.org/10.1007/s11205-013-0452-2"
  • Description: This paper explores various dynamics in the relationship between life satisfaction and education in South Africa using the 2008 National Income Dynamics Survey. The results indicate a strong positive association between educational attainment and individual satisfaction with life, which is true in the overall sample and for men and women. This positive relationship also holds for Black and Coloured individuals, but is insignificant in the Asian and White samples. Evidence indicates that education is a positional good, in that people who have attained more than the mean level of education in their relevant cluster are significantly more satisfied with life compared to those possessing less than the mean education.
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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

Lived bodies: women’s experience of sex and gender

  • Authors: Lothian, Julie-Anne
  • Date: 2014
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/69445 , vital:29538
  • Description: This thesis will discuss the category of women, as a social group, through a phenomenological understanding of women’s subjective experiences. In arguing for the phenomenological perspective of the lived body, I show the ways in which other conceptions of women’s embodied subjectivity ultimately fail to provide comprehensive accounts of the lived experience of being a woman. I begin with an investigation into how biological determinists hypothesise women’s bodies as sexed. I then move to respond to Judith Butler’s poststructuralist feminist account of the gendered body. Finally, I argue that the embodied experience of being a woman is best explained as an ambiguous relationship between socially constructed expectations of femininity and biological materiality.
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  • Date Issued: 2014

Losing, using, refusing, cruising: first-generation South African women academics narrate the complexity of marginality

  • Authors: Idahosa, Grace E , Vincent, Louise
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/141820 , vital:38007 , DOI: 10.1080/10130950.2014.874766
  • Description: In this article we ask how senior academic women in South Africa narrate their experience of being ‘outside in’ the teaching machine. Wide research literature documents the gross underrepresentation of women in senior positions in the academy. It has been argued that intertwined sexist, patriarchal and phallocentric knowledges and practices in academic institutions produce various forms of discrimination, inequality, oppression and marginalisation. Academic women report feeling invisible and retreating to the margins so as to avoid victimisation and discrimination. Others have pointed to the tension between the ‘tenure clock’ and ‘biological clock’ as a source of anxiety. However, experiences of academic women are not identical. In the context of studies showing the importance of existing personal and social resources, prior experience and having mentors and role models in the negotiation of inequality and discrimination, we document the narratives of women academics who are the first in their families to graduate with a university degree.
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  • Date Issued: 2014

Low-cost housing developments in South Africa miss the opportunities for household level urban greening

  • Authors: Shackleton, Charlie M , Hebinck, Paul , Kaoma, Humphrey , Chishaleshale, Mwale , Chinyimba, Abby , Shackleton, Sheona E , Gambiza, James , Gumbo, Davison
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/180967 , vital:43677 , xlink:href="https://doi.org/10.1016/j.landusepol.2013.10.002"
  • Description: Most developing countries of the world are experiencing large-scale migration from rural to urban areas. Many new migrants end up in low-cost or informal areas and slums with attendant environmental concerns. One dimension of improved urban sustainability is the provision of green spaces and trees. Whilst many countries have urban greening programmes for public spaces and streets, few have considered the status and potential contribution of trees from resident's own gardens. This paper reports firstly on the policy environment for urban forestry and greening in South Africa and secondly on the maintenance, use and appreciation of trees on private homesteads of residents of new and older low-income suburbs as well as informal housing areas from three small towns in South Africa. In particular we examine if the most recent centrally planned and built low-income housing schemes (called RDP suburbs in South Africa) have considered and incorporated plans or spaces for urban greenery in peoples’ homesteads. We found that broad environmental and sustainability concerns and statements are common in urban development and housing policies, but specific guidelines for implementation are generally absent. More specifically, urban forestry and tree planting are rarely mentioned in the broader land use and environmental policies other than the national forest act and subsequent regulations, but even there it is relatively superficial. In the study towns the prevalence, density and number of species of trees was lowest in the new RDP suburbs relative to the township and informal areas. Consequently, the contribution of tree products to local livelihoods was also lower in the RDP areas. Yet there were no differences in the level of appreciation of the value and intangible benefits of trees between residents from the three different suburbs. This shows that the failure to plan for and accommodate trees in new low-cost housing developments is missing an opportunity to improve overall urban sustainability and liveability and constraining the potential flows of tangible and intangible benefits to urban residents. Making opportunities for such in older suburbs is challenging because of space limitations and cost implications of retrospective provisions, but incorporation into plans for new low-cost housing development should be possible.
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  • Date Issued: 2014

Macbeth: The great doom’s image

  • Authors: Butler, Frederick G
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/454022 , vital:75305 , 10.4314/sisa.v26i1.5
  • Description: This lecture employs the old-fashioned technique of studying a group or cluster of images in order to arrive at a better understanding of the work. Macbeth has proved a particularly happy hunting ground for image chasers; this exercise differs from most others in attempting to show how a number of images, mainly in the first two acts and particularly in Act 1 Scene 7 and Act 2 scenes 1-6, recreate and then draw force from a sequence of quite specific events in the Christian ‘myth’ – rather in the manner that Joyce’s Ulysses exploits the Odyssey. Previous critics have detected in certain scenes references to particular incidents in that myth (such as the Porter’s parody of the Harrowing of Hell) and allusions to the general resurrection, as well as to the day of Judgement.
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  • Date Issued: 2014

Mini-review on the use of liquid membranes in the extraction of platinum group metals from mining and metal refinery wastewaters/side-streams

  • Authors: Moyo, Francis , Tandlich, Roman
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/75960 , vital:30487 , DOI: 10.4172/2155-6199.1000228
  • Description: The current mini-review focuses on the use of liquid membranes in the platinum group metal (PGM/PGMs) extraction from various types of wastewaters to prevent environmental pollution; and for the metal recovery to address the scarcity of the PGMs in the industrial cycles. The bulk liquid membranes have been used to the extracted PGMs from the (acidic) aqueous media with recoveries of up to 96.3 ± 2.5% of the original PGM amount. The extraction time generally ranges from 2 to 24 hours. The bulk membrane liquid in the PGM extraction will depend on the covalent structure of the extractant, the feed phase PGM concentration and the complex of the PGM in question that is actually extracted from the aqueous environment. The advantages of this type of liquid membrane include its operational simplicity, but the disadvantages include limited possibility to improve the extraction performance of the system. Literature data are encouraging as they indicate that extraction of PGMs from mining and metal-refinery side-streams does not suffer from interference from metal contaminants that are commonly found in the mining and metal refinery side-streams, e.g. iron. Thus further research should focus on the application of ELM to extraction of PGMs from said wastewaters and major research drive should focus on the use of the Taylorvortex column and the non-Newtonian ELMs. With the supported liquid membranes, 78-82% of the original PGM content could be recovered from model side-streams. The selectivity of the extraction for individual PGMs can be controlled by the extractant used.
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  • Date Issued: 2014

Mitonuclear discordance in genetic structure across the Atlantic/Indian Ocean biogeographical transition zone

  • Authors: Teske, Peter R , Papadopoulos, Isabelle , Barker, Nigel P , McQuaid, Christopher D , Beheregaray, Luciano B
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/444832 , vital:74301 , https://doi.org/10.1111/jbi.1220
  • Description: Based on mitochondrial DNA (mtDNA) data, many organisms with ranges spanning multiple biogeographical regions exhibit genetic structure across the transition zones between these regions, while others appear to be genetically homogenous. No clear link has been found between the presence or absence of such spatial genetic discontinuities and species' dispersal potential, confounding the formulation of general predictions concerning genetic structure. The fact that discrepancies between mtDNA and nuclear markers are common across semi‐permeable barriers suggests that a lack of structure could be attributable to mtDNA‐specific properties of inheritance. We re‐examined genetic structure in the coastal crab Hymenosoma orbiculare, a species that is represented by a single mtDNA lineage across the Atlantic/Indian Ocean biogeographical transition zone, by comparing mtDNA data with nuclear DNA data.
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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
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