List of Titles

Editorial: tracing actors, actants and relational dynamics in environmental education research

Authors: Lotz-Sisitka, Heila
Date: 2006
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/67400 , vital:29084 , https://www.ajol.info/index.php/sajee/article/view/122719
Description: publisher version , Introduction: This edition of the EEASA Journal provides insight into a range of relationships in the field of environmental education, and the complexities that exist around them, as reflected in the combination of papers. This Editorial picks up on the methodological ‘note’ (or is it a challenge?) provided by Godwell Nhamo in his paper in this edition of the journal. He provides a description of the possibilities that actor network theory provides for describing and explaining environmental policy processes, and recommends that environmental educators consider this methodology in their analyses. In particular, he refers environmental educators to applications of actor network theory for tracing relational dynamics between actors (i.e., environmental education practitioners) and actants which are non-human referents (e.g., the UN Decade of Education for Sustainable Development and UNESCO’s (2005) International Implementation Scheme). In response to his paper, I have chosen to ‘pick up’ on this methodological discussion in this Editorial, by considering aspects of this theoretical perspective in describing the ‘happenings’ that occur across the pages of this edition of the EEASA Journal. In doing so, I highlight (in part) the diversity of actors and actants that are influencing the field of environmental education, their subject matter and contexts, and I highlight the relational dynamics that become evident when one accepts a methodology that aims to trace such dynamics. In particular, this Editorial considers how ‘The language of actors, actants and actor/actant-networks brings to the fore the relationships and complexities that exist around them’ (Nhamo, this edition).
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Evaluation of Bacillus thuringiensis Berliner as an alternative control of small hive beetles, Aethina tumida Murray (Coleoptera: Nitidulidae)

- Buchholz, S, Neumann, Peter, Neumann, K, Hepburn, H Randall

Authors: Buchholz, S , Neumann, Peter , Neumann, K , Hepburn, H Randall
Date: 2006
Language: English
Type: Article
Identifier: vital:6929 , http://hdl.handle.net/10962/d1011945
Description: Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401®), B. thuringiensis var. kurstaki (Novodor®) and B. thuringiensis var. San Diego tenebrionis (Jackpot®)] and Perizin® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.
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Implementing the GrabCut segmentation technique as a plugin for the GIMP

- Marsh, Matthew, Bangay, Shaun D, Lobb, Adele

Authors: Marsh, Matthew , Bangay, Shaun D , Lobb, Adele
Date: 2006
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/433207 , vital:72951 , https://doi.org/10.1145/1108590.1108618
Description: Image segmentation requires a segmentation tool that is fast and easy to use. The GIMP has built in segmentation tools, but under some circumstances these tools perform badly. "GrabCut" is an innovative segmentation technique that uses both region and boundary information in order to perform segmentation. Several variations on the "GrabCut" algorithm have been implemented as a plugin for the GIMP. The results obtained using "GrabCut" are comparable, and often better than the results of all the other built in segmentation tools.
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Interactions of fishes with particular reference to coelacanths in the canyons at Sodwana Bay and the St Lucia Marine Protected Area of South Africa

- Heemstra, Phillip C, Fricke, H, Hissmann, K

Authors: Heemstra, Phillip C , Fricke, H , Hissmann, K
Date: 2006
Language: English
Type: text , Article
Identifier: vital:7130 , http://hdl.handle.net/10962/d1011771
Description: The deep demersal fish fauna at depths of 100–400min canyons off the St Lucia Marine Protected Area along the north coast of KwaZulu-Natal is compared with similar fish communities at the Comoro Islands and in the Indo-Pacific region. Fifty-four fish species were seen or photographed from the submersible Jago or by the discovery team of scuba divers in the coelacanth, Latimeria chalumnae, habitat of the canyons off Sodwana Bay. An additional 94 fish species known from depths of 100–200 m along the coast of northern KwaZulu-Natal are likely to occur in the canyon habitat. The fish fauna of the Sodwana canyons shares at least 18 species with the deep demersal fish community off tropical coral reefs of the Indo-Pacific region. Thirty-seven of the Sodwana canyon fishes are also known from the coelacanth habitat in the Comoros.
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Karyology of the redfin minnows, genus Pseudobarbus Smith, 1841 (Teleostei: Cyprinidae): one of the evolutionarily tetraploid lineages of South African barbines

- Naran, Daksha, Skelton, Paul H, Villet, Martin H

Authors: Naran, Daksha , Skelton, Paul H , Villet, Martin H
Date: 2006
Language: English
Type: Article
Identifier: vital:6770 , http://hdl.handle.net/10962/d1008063
Description: The karyotypes of six species of Pseudobarbus Smith, 1841, namely P. afer (Peters, 1864), P. asper (Boulenger, 1911), P. burchelli Smith, 1841, P. burgi (Boulenger, 1911), P. phlegethon (Barnard, 1938) and P. tenuis (Barnard, 1938), were examined by conventional Giemsa staining and described. All six karyotypes have 2n = 100 chromosomes, dominated by biarmed chromosomes, as does the only other member of the genus, P. quathlambae (Barnard, 1938). Sex-related intraspecific karyotype variation was not found. The shared chromosome numbers and general similarity of the karyotypes (FN = 186–192) provide a new synapomorphy to support their monophyly, which is already indicated by anatomical and mtDNA markers. Karyotype evolution within the genus has been accompanied by chromosomal inversions and centromeric shifts. Comparison of the diploid number found in Pseudobarbus with other African barbine cyprinines, which have in the region of 2n=50 and lower FNs, suggests a tetraploid evolutionary origin of the genus, possibly by allotetraploidy.
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The identification of mammalian species through the classification of hair patterns using image pattern recognition

- Moyo, Thamasanqa, Bangay, Shaun D, Foster, Gregory G

Authors: Moyo, Thamasanqa , Bangay, Shaun D , Foster, Gregory G
Date: 2006
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/432938 , vital:72914 , https://doi.org/10.1145/1108590.1108619
Description: The identification of mammals through the use of their hair is important in the fields of forensics and ecology. The application of computer pattern recognition techniques to this process provides a means of reducing the subjectivity found in the process, as manual techniques rely on the interpretation of a human expert rather than quantitative measures. The first application of image pattern recognition techniques to the classification of African mammalian species using hair patterns is presented. This application uses a 2D Gabor filter-bank and motivates the use of moments to classify hair scale patterns. Application of a 2D Gabor filter-bank to hair scale processing provides results of 52% accuracy when using a filter-bank of size four and 72% accuracy when using a filter-bank of size eight. These initial results indicate that 2D Gabor filters produce information that may be successfully used to classify hair according to images of its patterns.
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Urban-rural contrasts in Arbor Week in South Africa

- Guthrie, G, Shackleton, Charlie M

Authors: Guthrie, G , Shackleton, Charlie M
Date: 2006
Language: English
Type: Article
Identifier: vital:6631 , http://hdl.handle.net/10962/d1006823
Description: Trees provide people with environmental benefits. Greening projects have been implemented worldwide, but many of them have frustratingly low participation levels. In South Africa, tree-planting campaigns such as the national Arbor Week are generally aimed at schools. Because of the remoteness of rural schools, there are urban / rural disparities in standards of education, infrastructure and support provided at schools, and hence we hypothesized that these disparities would be mirrored in tree-planting activities associated with national Arbor Week. In the study reported here, 236 urban and rural schools were assessed by means of postal surveys and subsampled via direct interviews, as to their participation in Arbor Week activities, the provision of trees, constraints to participation, and the perceived benefits of planting trees. Very few urban schools had never participated in any Arbor Week activities, whereas one-fifth of rural ones had never participated in any way. Urban schools participated in a greater number of Arbor Week activities than rural schools, including tree-planting, displaying posters and having speeches. Thus, overall information about Arbor Week is lacking in rural areas compared to urban ones. Rural schools derived more benefits from planting trees, with shade and education being the primary benefits overall. Rural schools were supplied with trees by NGOs, whereas urban schools received trees from individual or company donations. The major constraints to tree-planting are livestock damage, water shortages, vandalism and theft. These obstacles need to be addressed in a holistic fashion in order to improve the participation and success of National Arbor Week as a vehicle for tree-planting and environmental awareness.
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What does the movement of the Phloem-mobile symplastic tracer, 5,6-carboxyfluorescein in shoots of Pisum Sativum L. Indicate - the existence of a symplastic transport system? - a bid to answer some puzzling questions

- Ade-Ademilua, Omobolanle Elizabeth, Botha, Christiaan E J

Authors: Ade-Ademilua, Omobolanle Elizabeth , Botha, Christiaan E J
Date: 2006
Language: English
Type: Article
Identifier: vital:6492 , http://hdl.handle.net/10962/d1004475 , http://dx.doi.org/10.3923/ajpp.2006.127.131
Description: Like other members of the Fabaceae, the minor veins of Pisum are categorized as a closed system termed type 2 minor vein configuration due to the presence of few or no plasmodesmal connections between the sieve element-transfer cell complex (SE-TCC) and the adjacent cells (Gamalei, 1989; van Bel and Gamalei, 1991) Pisum is classified further into the category of type 2 b minor vein configuration due to the presence of transfer cells with the characteristic wall ingrowths in the minor vein phloem (Gamalei, 1989). According to van Bel et al. (1992), there is a correlation between minor vein configuration and phloem loading. However, by reason of low plasmodesmal frequency, the pathway of the flow of assimilates in plants with type 2 minor vein configuration is considered to be apoplasmic (Gamalei, 1989; van Bel and Gamalei, 1991). Therefore, present reports on the movement of phloem-mobile 5,6-carboxyfluorescein, a known symplamically transported compound between pea leaflets raises some doubts on the accession that transport within the phloem in pea is strictly apoplasmic. In this study we look at different points of arguments and try to offer our explanation and conclusions on the transport pathways that are likely to exist in Pisum.
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Selecting medicinal plants for cultivation at Nqabara on the Eastern Cape Wild Coast, South Africa

- Keirungi, Juliana, Fabricius, Christo

Authors: Keirungi, Juliana , Fabricius, Christo
Date: 2005
Language: English
Type: Article
Identifier: vital:6637 , http://hdl.handle.net/10962/d1006862
Description: [From introduction:] The intensive harvesting of medicinal plants for commercial trade in South Africa poses a threat to many species. Cultivation has therefore been considered as an alternative to collection in the wild. This paper aims to assess the feasibility of cultivating medicinal plants in the Nqabara Administrative Area on South Africa's Wild Coast. A combination of participatory and formal research methods was used to collect data on the importance of medicinal plants, collection localities, market prices, the time spent collecting plants and their ease of cultivation. The values attached to medicinal plants were mainly dependent on their market prices. Four of the five Nqabara traditional healers interviewed cultivated these plants in their home gardens, but many medicinal products were obtained in indigenous forests from the bark of large trees, which were unsuitable for cultivation. Collectors said that the proximity of forests to their homesteads and the richness of forests in medicinal plants influenced their selection of harvesting localities. There was no correlation between time spent collecting species and their market prices. These prices were, however, positively correlated with the species' perceived healing properties. Users acknowledged that harvesting had an adverse effect on large trees, are eager to cultivate them and are taking action to conserve indigenous forests. Community-based enterprises should focus on species that are easy to cultivate and have a high demand, such as Stangeria eriopus, Acalypha glabrata and Behnia reticulata but not Araujia sericifera, which is exotic and abundant. The main barriers to commercial cultivation are availability of suitable land, water, lack of start-up capital, and access to markets and to seeds. Cultivation of medicinal plants could contribute to the economic empowerment of women in rural areas.
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The diet of Cape clawless otters at two sites along the Bloukrans River, Eastern Cape Province, South Africa

- Parker, Daniel M, Burchell, R K, Bernard, Ric T F

Authors: Parker, Daniel M , Burchell, R K , Bernard, Ric T F
Date: 2005
Language: English
Type: Article
Identifier: vital:6959 , http://hdl.handle.net/10962/d1012004
Description: The diet of Cape clawless otters was assessed at two sites along the Bloukrans River using faecal analysis. Spraints (n = 78) were collected during 2000 and 2001 and analysed using the relative frequency of occurrence and the reconstituted wet weight methods. Both methods found crab (Potamonautes perlatus) to be the most important component (>50%) of the diet. Frog, Xenopus and Rana spp., (11–42%) was the second most important component while fish (Micropteris salmoides) was relatively unimportant (<14%). Although the diet of Cape clawless otters in the Eastern Cape Province was similar to that reported elsewhere, the fact that they were preying on an alien invasive fish and not the indigenous endemic Sandelia bainsii is significant. The validity of faecal analysis methods is also discussed.
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An analysis of automatically scaled F1 layer data over Grahamstown, South Africa

- Jacobs, Linda, Poole, Allon W V, McKinnell, Lee-Anne

Authors: Jacobs, Linda , Poole, Allon W V , McKinnell, Lee-Anne
Date: 2004
Language: English
Type: text , Article
Identifier: vital:6808 , http://hdl.handle.net/10962/d1004194
Description: This paper describes an analysis of automatically scaled F1 layer data over Grahamstown, South Africa (33.3°S, 26.5°E). An application for real time raytracing through the South African ionosphere was identified, and for this application real time evaluation of the electron density profile is essential. Raw real time virtual height data are provided by a Lowell Digisonde (DPS), which employs the automatic scaling software, ARTIST whose output includes the virtual-to-real height data conversion. Experience has shown that there are times when the raytracing performance is degraded because of difficulties surrounding the real time characterisation of the F1 region by ARTIST. The purpose of this investigation is to establish the extent of the problem, the times and conditions under which it occurs, with a view to formulating remedial alternative strategies, such as predictive modelling.
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An indirect method to assess the energy expenditure of manual labourers in situ

- Scott, Patricia A, Christie, Candice J

Authors: Scott, Patricia A , Christie, Candice J
Date: 2004
Language: English
Type: Article
Identifier: vital:6742 , http://hdl.handle.net/10962/d1008390
Description: The aim of ergonomics is to identify any incompatibility between worker capabilities and the demands of their job. It is therefore desirable that in a developing country such as South Africa we have some basic, yet valid and usable means of measuring worker responses to physically demanding manual tasks. Extensive ergonomic research has been conducted in the controlled environment of laboratories around the globe, but only a limited number of investigations have been conducted in the workplace. This is due to the impossibility of controlling the extraneous factors such as the environment and changing workloads while assessing worker responses, plus the impracticality of using hi-tech equipment under difficult conditions on unsophisticated workers. The likelihood of obtaining ‘natural’ responses thereby is low. The focus of this study was to establish a less invasive means of assessing the physiological responses (specifically energy expenditure) of manual labourers working in the field. Twenty-three forestry stackers were assessed. Heart-rate responses were recorded during a full shift, after which the workers participated in a submaximal incremental step test. Subjects were fitted with a gas analyser, and heart rate and oxygen consumption responses were measured throughout the 12-min test. These data were used to establish a regression equation based on the relationship between heart rate and oxygen consumption (r² = 0.49; r = 0.69). Using this equation (y=0.26x – 6.42), one can measure heart rate in the field and predict the energy cost of manual tasks.
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Emerging Models of Teacher Training: The Case of South Africa

- Wilmot, P Dianne

Authors: Wilmot, P Dianne
Date: 2004
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/482922 , vital:78702 , https://doi.org/10.1080/09669580408668507
Description: Since the transition to democracy in 1994, South African education has witnessed remarkable changes. Teacher training, like all other elements of the national education system, is part of an evolving post-apartheid educational landscape. This paper describes important forces of change that have helped to shape the education landscape and it explores the significance of these on teacher training. The complexity of change, as a process that is frequently unpredictable and contradictory, is illuminated. The writer contends that change is fraught with uncertainties and challenges, yet vibrant, dynamic and full of opportunities. For the goals of transformation to be achieved, the thrust of teacher training must be towards enhanced professional status and responsibility. Central to this is the development of critically reflexive practitioners who have the capacity and the will to act as agents of change in a period of transformation.
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Genetic analysis of the Octopus vulgaris population on the coast of South Africa

- Oosthuizen, Ané, Jiwaji, Meesbah, Shaw, Paul W

Authors: Oosthuizen, Ané , Jiwaji, Meesbah , Shaw, Paul W
Date: 2004
Language: English
Type: Article
Identifier: vital:6761 , http://hdl.handle.net/10962/d1007922
Description: This study on Octopus vulgaris focused on the COIII gene region of mitochondrial DNA. Sequences from 21 samples from the Eastern Cape, and 14 samples from the Western Cape, were compared to determine whether different populations exist along the South African coast. A 380-bp segment of the COIII region of mtDNA was amplified using the polymerase chain reaction with specific designed primers. Phylogenetic inference was made using maximum parsimony (MP), maximum likelihood (ML), and distance based methods. All sequences conformed to a single haplotype. Lack of variation within and between east and west coast samples precluded further population genetic analysis. The sequence obtained in this study was also compared with other sequences lodged in the Genbank database. Phylogenetically, the South African O. vulgaris is closely related to O. vulgaris from Senegal (0.67% divergence) and the Mediterranean (1.51% divergence). Within the Mediterranean group, O. vulgaris from South Africa displayed less sequence divergence from Senegalese and Mediterranean individuals than O. vulgaris from Venezuela (3.85%) and Taiwan (3.87%). These data do not, therefore, refute the hypothesis of a single O. vulgaris genetic population around the coast.
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iLanga: A next generation VOIP-based, TDM-enabled PBX

- Penton J, Terzoli, Alfredo

Authors: Penton J , Terzoli, Alfredo
Date: 2004
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/427591 , vital:72449 , https://www.researchgate.net/profile/Alfredo-Terzoli/publication/228963823_iLanga_a_next_generation_VoIP-based_TDM-enabled_PBX/links/02bfe51344c9db1c75000000/iLanga-a-next-generation-VoIP-based-TDM-enabled-PBX.pdf
Description: iLanga is a complete, cost-effective, computer-based PBX built and be-ing prepared as a commercial product at Rhodes University. Running on a single PC (in its minimal configuration), iLanga provides all the fea-tures of a conventional PBX together with full support for VoIP. In this paper we introduce and discuss iLanga’s architecture, emphasising its main components, Asterisk, SIP Express Router (SER) and OpenH323 Gatekeeper (OpenGK). We also discuss the development of new ser-vices and features in iLanga as well as the possibility to manage and customize it. The paper concludes with the description of a pilot de-ployment of iLanga that we are using to test and refine the system.
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Iris colour in passerine birds: why be bright-eyed?

- Craig, Adrian J F K, Hulley, Patrick E

Authors: Craig, Adrian J F K , Hulley, Patrick E
Date: 2004
Language: English
Type: Article
Identifier: vital:6902 , http://hdl.handle.net/10962/d1011756
Description: An initial survey of iris coloration in passerine birds (Aves: Passeriformes) showed that a brightly pigmented iris is much more common in southern African and Australian birds than in those from Europe, temperate North America, and Venezuela. However, the only statistical correlation reflected the distribution of particular bird families in these regions. Ten family-level groups considered to represent monophyletic taxa were then selected for a more detailed analysis, comparing iris coloration with distribution, status, taxonomy, plumage patterns, and some biological and behavioural characters for 1143 species. No pattern associating iris colour with particular traits was common to all families, but within families there were statistically significant associations with both plumage and biology. Our expectation that social behaviour would be an important predictor of iris colour was not supported, but critical information is still lacking for many species. Future studies of avian behavioural ecology should examine critically the role of iris coloration in individual species. , Rhodes Centenary issue
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Iris colour in passerine birds: why be bright-eyed?

- Craig, Adrian J F K, Hulley, Patrick E

Authors: Craig, Adrian J F K , Hulley, Patrick E
Date: 2004
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/449872 , vital:74860 , https://hdl.handle.net/10520/EJC96183
Description: An initial survey of iris coloration in passerine birds (Aves : Passeriformes) showed that a brightly pigmented iris is much more common in southern African and Australian birds than in those from Europe, temperate North America, and Venezuela. However, the only statistical correlation reflected the distribution of particular bird families in these regions. Ten family-level groups considered to represent monophyletic taxa were then selected for a more detailed analysis, comparing iris coloration with distribution, status, taxonomy, plumage patterns, and some biological and behavioural characters for 1143 species. No pattern associating iris colour with particular traits was common to all families, but within families there were statistically significant associations with both plumage and biology. Our expectation that social behaviour would be an important predictor of iris colour was not supported, but critical information is still lacking for many species. Future studies of avian behavioural ecology should examine critically the role of iris coloration in individual species.
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Mycorrhizal status of indigenous tree species in a forest biome of the Eastern Cape, South Africa

- Hawley, Greer L, Dames, Joanna F

Authors: Hawley, Greer L , Dames, Joanna F
Date: 2004
Language: English
Type: Article
Identifier: vital:6458 , http://hdl.handle.net/10962/d1005774
Description: Mycorrhizal fungi are intimately associated with plant roots, affecting plant growth, health and increasing the plants' tolerance to environmental stress. Several mycorrhizal types are recognized based primarily on morphological characteristics within plant roots. When considering propagation and management of an indigenous plant species, it is essential to know its mycorrhizal status. Root samples from 17 tree species common to the pockets of forest in the Eastern Cape province, and representing the families Rubiaceae, Scrophulariaceae, Oleaceae, Podocarpaceae, Myrsinaceae, Anacardiaceae, Caesalpinoideae, Papilionoideae, Rutaceae, Meliaceae, Celastraceae, Flacouticeae and Ebenaceae, were sampled and examined for mycorrhizal colonization. Microscopic examination of all the species produced evidence of morphological structures indicative of endomycorrhizal associations as indicated by the presence of intercellular hyphae combined with vesicles, arbuscules or hyphal coils. Hyphal coils (also known as Paris-type associations) appeared to be abundant, especially within the Cassine genus. Arbuscules (also known as Arum-type associations) were scarce but sometimes present, and vesicles were prolific in Olea capensis. Most of the tree species examined have been assigned arbuscular mycorrhizal status. No ectomycorrhizal associations were recorded
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