The localisation into isiXhosa of the iLanga telephone system
- Authors: Dalvit, Lorenzo , Tsietsi, Mosiuoa , Terzoli, Alfredo , Maseko, Pamela , Sam, Msindisi , Mapi, Thandeka
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431358 , vital:72767 , https://nru.uncst.go.ug/bitstream/handle/123456789/6552/Information%20Communica-tion%20Technologies%20%20page%20410.pdf?sequence=1isAllowed=y#page=256
- Description: In this paper we describe the localisation of iLanga, a VoIP PBX sys-tem, into isiXhosa. In South Africa, for social and political reasons, mak-ing systems available in the African languages is becoming more and more important. On the one hand, it gives access to the use of technol-ogy to people who are not fluent in English. On the other hand, it has a strong symbolic value. Although a variety of software is already availa-ble in a number of African languages, localisation in such language is still in its early stage. The process presented interesting challenges both from the technical and the linguistic point of view.
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- Date Issued: 2008
The photophysical studies of a mixture of CdTe quantum dots and negatively charged zinc phthalocyanines
- Authors: Moeno, Sharon , Nyokong, Tebello
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268663 , vital:54220 , xlink:href="https://doi.org/10.1016/j.poly.2008.03.007"
- Description: Fluorescence resonance energy transfer (FRET) studies were carried out with quantum dots capped with thioglycolic acid (TGA) and 2-mercaptoethanol (2-ME) and negatively charged phthalocyanines {Zn tetracarboxy (ZnTCPc), Zn octacarboxy (ZnOCPc) and Zn tetrasulfo (ZnTSPc) phthalocyinines} in a 0.1 NaOH:EtOH (50:50) solvent mixture. The best overlap between emission spectra of the donor (QDs) and the absorption spectra of the acceptor (ZnPc derivatives) was observed for TGA capped QDs, very little overlap was obtained for 2-ME QDs. ZnTSPc gave the highest FRET efficiency (0.3), with ZnOCPc and ZnTCPc giving a FRET efficiency of 0.2. The ΦT values of the MPcs generally decreased in the presence of the QD whereas the triplet lifetimes (τT) of the ZnPc derivatives were higher in the presence of QDs.
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- Date Issued: 2008
The population dynamics of the estuarine isopod Exosphaeroma hylocoetes (Barnard, 1940) within three temporarily open/closed southern African estuaries
- Authors: Henninger, Tony O , Froneman, P William , Hodgson, Alan N
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447627 , vital:74662 , https://doi.org/10.1080/15627020.2008.11657237
- Description: The population dynamics of the estuarine isopod, Exosphaeroma hylocoetes, was investigated monthly from February 2006 to August 2007 in three temporarily open/closed Eastern Cape estuaries, the East and West Kleinemonde and Kasouga Estuaries. Mean isopod abundances and biomasses ranged between 0 and 4791 ind/m2 and 0 and 9.65 mg/dwt/m2 in the West Kleinemonde Estuary and between 0 and 108 ind/m2 and 0 and 0.318 mg/dwt/m2 in the nearby East Kleinemonde Estuary. In the Kasouga Estuary, the values ranged between 0 and 3650 ind/m2 and 0 and 5.105 mg/dwt/m2. Temporal changes in the abundance and biomass of E. hylocoetes within the three systems was primarily linked to mouth phase, with populations crashing when the mouth was open and to a lesser extent, seasonality. In all three estuaries maximum abundance and biomass was recorded in the middle reaches, which could be ascribed to the presence of submerged macrophytes. E. hylocoetes demonstrates strong sexual dimorphism, with males being significantly larger than females (P 0.05). Sex ratios were skewed in favour of females in all three estuaries.
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- Date Issued: 2008
The Postcolonial heart of African philosophy
- Authors: Tabensky, Pedro
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/305762 , vital:58610 , xlink:href="https://hdl.handle.net/10520/EJC96056"
- Description: This piece is one of among a handful that seek in the first instance to reveal the origin of African philosophy as an academic discipline, the source of its unity and distinctiveness. The discipline of African philosophy originates in tragedy, out of pain, confusion and rage stemming from colonial destruction; destruction that is responsible for what Fanon calls the ‘negro neurosis’ caused by what Biko would describe as the unbearable fusion of colonised and coloniser. I argue that the birth of African philosophy as an academic discipline is largely responsible for its character and, crucially, for its distinctive creative possibilities.
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- Date Issued: 2008
The relationship between emergence of the shortest path and information value using ant-like agents
- Authors: Chibaya, Colin , Bangay, Shaun D
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433318 , vital:72961 , https://doi.org/10.1145/1456659.1456663
- Description: Ant-like agents forage between two points. These agents' probabilistic movements are based on the use of two pheromones; one marking trails towards the goal and another marking trails back to the starting point. Path selection decisions are influenced by the relative levels of attractive and repulsive pheromone in each agent's local environment. Our work in [5] evaluates three pheromone perception strategies, investigating path formation speed, quality, directionality, robustness and adaptability under different parameter settings(degree of randomness, pheromone evaporation rate and pheromone diffusion rate).
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- Date Issued: 2008
The role of indigenous knowledge in computer education in Africa
- Authors: Dalvit, Lorenzo , Murray, Sarah , Terzoli, Alfredo
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431033 , vital:72739 , https://doi.org/10.1007/978-0-387-09729-9_43
- Description: The integration of indigenous knowledge/languages in formal education is a contentious issue in post-colonial Africa. For historical and econom-ic reasons, these are devalued in the formal education system. We ar-gue that appropriate use of indigenous knowledge/languages can em-power African students academically even in typically “Western” disci-plines, such as Computer Science. We discuss the potential role of in-digenous languages/knowledge in ICT education and then describe an intervention, supporting students from marginalised communities, at a South African University.
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- Date Issued: 2008
Towards a taxonomy of network scanning techniques
- Authors: Barnett, Richard J , Irwin, Barry V W
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430310 , vital:72682 , https://doi.org/10.1145/1456659.1456660
- Description: Network scanning is a common reconnaissance activity in network in-trusion. Despite this, it's classification remains vague and detection sys-tems in current Network Intrusion Detection Systems are incapable of detecting many forms of scanning traffic. This paper presents a classi-fication of network scanning and illustrates how complex and varied this activity is. The presented classification extends previous, well known, definitions of scanning traffic in a manner which reflects this complexity.
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- Date Issued: 2008
Transitions towards a knowledge society: Aspectual pre-evaluation of a culture-sensitive implementation framework
- Authors: Thinyane, Mamello , Terzoli, Alfredo , Clayton, Peter G
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431054 , vital:72741 , https://doi.org/10.1007/978-0-387-09729-9_41
- Description: Information and Communication Technology (ICT) is aiding the transi-tion of society into information society and ultimately knowledge society. Embedded within ICT are the cultural and philosophical undercurrents of the society in which the ICT solutions are developed, currently pre-dominantly the Western culture. The proliferation of ICT is therefore in-advertedly leading to more Westernization of the world. It is important, therefore, that ICT solutions are culture sensitive and flexible enough to be situated within different cultures. To that end, we utilize Herman Dooyeweerd’s Theory of Modal Aspects to analyze a framework we has developed for implementation of locally situated knowledge based systems, to determine its efficacy in addressing the different modal as-pects, which make up the total experience and cultural expressiveness of societies.
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- Date Issued: 2008
Tuning the redox properties of Co-N4 macrocyclic complexes for the catalytic electrooxidation of glucose
- Authors: Villagra, Evelyn , Bedioui, Fethi , Nyokong, Tebello , Canales, J Carlos , Sancy, Mamie , Páez, Maritza A , Costamagna, Juan , Zagal, Jose H
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268675 , vital:54221 , xlink:href="https://doi.org/10.1016/j.electacta.2008.02.006"
- Description: Graphite electrodes modified with four different cobalt N4 macrocyclics, namely Co tetrapentapyridinophthalocyanine, (CoTPenPyrPc), Co tetrapyridinoporphyrazine (CoTPyPz), Co octa(hydroxyethylthio)phthalocyanine (CoOEHTPc) and Co tetranitrophthalocyanine (CoTNPc) exhibit catalytic activity for the oxidation of glucose in alkaline media. The purpose of this work is to establish correlations between the catalytic activity of these complexes and their redox potential. The activity of the different modified electrodes was tested by linear voltammetry under hydrodynamic conditions using the rotating disk technique. Tafel plots constructed from mass-transport corrected currents give slopes ranging from 0.080 to 0.160 V/decade for the different catalysts which suggests that a first one-electron step is rate controlling with the symmetry of the energy barrier depending on the nature of the ligand of the Co complex. A plot of log I versus the Co(II)/(I) formal potential gives a volcano curve that also includes catalysts studied previously. This illustrates the concept that the formal potential of the catalyst needs to be tuned to a certain value for achieving maximum activity. A theoretical interpretation of these results is given in terms of Langmuir isotherms for the adsorption of glucose on the Co sites of the surface-confined metal complexes.
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- Date Issued: 2008
Underlying mechanisms affecting institutionalisation of environmental education courses in Southern Africa
- Authors: Lupele, Justin
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386926 , vital:68188 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122773"
- Description: This paper discusses the underlying causal mechanisms that enabled or constrained institutionalisation of environmental education in 12 institutions in eight countries in southern Africa. The study was carried out in the context of the Southern Africa Development Community Regional Environmental Education Support Programme’s Course Development Network (CDN). This paper reports on part of the author's doctoral study and draws on critical realism as the ontological lens. Data analysis was done by means of a retroductive mode of inference, as articulated by Danermark, Ekström, Jakosben and Karlsson (2002). The paper demonstrates that there are a number of underlying causal mechanisms, which may enable or constrain institutionalisation of environmental education. They include factors at play at both national and institutional level; namely, responsiveness to national and institutional needs, recognition and ownership, accreditation and certification, institutional culture and politics, short course support structure and support from colleagues. As part of the discussions of the results of the study, I have advanced some retroductive theories that suggest causal mechanisms beyond the empirical data based on the participants’ experiences and events in the CDN.
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- Date Issued: 2008
Using inetvis to evaluate snort and bro scan detection on a network telescope
- Authors: Irwin, Barry V W , van Riel, J P
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429981 , vital:72656 , https://doi.org/10.1007/978-3-540-78243-8_17
- Description: This paper presents an investigative analysis of net-work scans and scan detection algorithms. Visualisa-tion is employed to review network telescope traffic and identify incidents of scan activity. Some of the identified phenomena appear to be novel forms of host discovery. Scan detection algorithms used by the Snort and Bro intrusion detection systems are cri-tiqued by comparing the visualised scans with alert output. Where human assessment disagrees with the alert output, explanations are sought by analysing the detection algorithms. The Snort and Bro algorithms are based on counting unique connection attempts to destination addresses and ports. For Snort, notable false positive and false negative cases result due to a grossly oversimplified method of counting unique destination addresses and ports.
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- Date Issued: 2008
Volcano correlations for the reactivity of surface-confined cobalt N4-macrocyclics for the electrocatalytic oxidation of 2-mercaptoacetate
- Authors: Claußen, Jan A , Ochoa, Gonzalo , Páez, Maritza , Costamagno, Juan , Gulppi, Miguel , Nyokong, Tebello , Bedioui, Fethi , Zagal, José H
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268688 , vital:54222 , xlink:href="https://doi.org/10.1007/s10008-007-0336-y"
- Description: We have investigated the electrocatalytic activity of several substituted and unsubstituted cobalt–phthalocyanines of substituted tetraphenyl porphyrins and of vitamin B12, for the electro-oxidation of 2-mercaptoacetate, with the complexes pre-adsorbed on a pyrolytic graphite electrode. Several N4-macrocyclic were used to have a wide variety of Co(II)/(I) formal potentials. The electrocatalytic activity, measured as current at constant potential, increases with the Co(II)/(I) redox potential for porphyrins as Co–pentafluorotetraphenylporphyrin larger than Co–tetrasulfonatotetraphenylporphyrin larger than Co-2,2′,2″,2‴tetra-aminotetraphenylporphyrin and decreases for cobalt phthalocyanines as Co-3,4-octaethylhexyloxyphthalocyanine > Co–octamethoxyphthalocyanine > Co–tetranitrophthalocyanine Co–tetraaminophthalocyanine > Co–unsubstituted phthalocyanine > Co–tetrasulfonatophthalocyanine > Co–perfluorinated phthalocyanine. Vitamin B12 exhibits the maximum activity. A correlation of log I (at constant potential) versus the Co(II)/(I) formal potential of the catalysts gives a volcano curve. This clearly shows that the search for better catalysts for this reaction point to those N4-macrocyclic complexes with Co(II)/(I) formal potentials close to −0.84 V versus SCE, which correspond to an optimum situation for the interaction of the thiol with the active site.
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- Date Issued: 2008
What future subordinates will value in their leaders
- Authors: Cox, A , Amos, Trevor L , Baxter, Jeremy
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/270992 , vital:54499 , xlink:href="https://hdl.handle.net/10520/EJC51031"
- Description: Leaders should not randomly choose a leadership style. To be effective, leaders need to ensure that their leadership style is congruent with what subordinates value. The focus of this study is on what the future South African graduate workforce will value in a leader. The female and male respondents in this study emphasise similar leadership values, indicating that there is no distinct set of competencies that will be valued separately by males and females. The same was found for respondents of different cultures, namely African, Coloured, Indian, White and other. With respect to both gender and culture, the respondents emphasise a mixture of African and Western leadership values. This supports the idea that to be effective in South Africa, leaders need to understand the prevailing national cultural values before simply applying ''foreign'' leadership models and theories based upon cultural values found in the West. This research finds that irrespective of gender and culture in the South African workplace, to be effective, leaders need to be loyal and inspirational, have vision and integrity and must be open and honest with their subordinates. Leaders should avoid being autocratic, strict, religious, ritualistic and traditional. They should also avoid using consensus and perceived external control.
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- Date Issued: 2008
A Digital Forensic investigative model for business organisations
- Authors: Forrester, Jock , Irwin, Barry V W
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430078 , vital:72664 , https://www.researchgate.net/profile/Barry-Ir-win/publication/228783555_A_Digital_Forensic_investigative_model_for_business_organisations/links/53e9c5e80cf28f342f414987/A-Digital-Forensic-investigative-model-for-business-organisations.pdf
- Description: When a digital incident occurs there are generally three courses of ac-tions that are taken, generally dependant on the type of organisation within which the incident occurs, or which is responding the event. In the case of law enforcement the priority is to secure the crime scene, followed by the identification of evidentiary sources which should be dispatched to a specialist laboratory for analysis. In the case of an inci-dent military (or similar critical infrastructures) infrastructure the primary goal becomes one of risk identification and elimination, followed by re-covery and possible offensive measures. Where financial impact is caused by an incident, and revenue earning potential is adversely af-fected, as in the case of most commercial organisations), root cause analysis, and system remediation is of primary concern, with in-depth analysis of the how and why left until systems have been restored.
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- Date Issued: 2007
A naive salience-based method for speaker identification in fiction books
- Authors: Glass, Kevin R , Bangay, Shaun D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432627 , vital:72888 , https://pubmed.ncbi.nlm.nih.gov/10350927/
- Description: This paper presents a salience-based technique for the annotation of directly quoted speech from fiction text. In particular, this paper determines to what extent a naïve (without the use of complex machine learning or knowledge-based techniques) scoring technique can be used for the identification of the speaker of speech quotes. The presented technique makes use of a scoring technique, similar to that commonly found in knowledge-poor anaphora resolution research, as well as a set of hand-coded rules for the final identification of the speaker of each quote in the text. Speaker identification is shown to be achieved using three tasks: the identification of a speech-verb associated with a quote with a recall of 94.41%; the identification of the actor associated with a quote with a recall of 88.22%; and the selection of a speaker with an accuracy of 79.40%.
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- Date Issued: 2007
A probabilistic movement model for shortest path formation in virtual ant-like agents
- Authors: Chibaya, Colin , Bangay, Shaun D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433125 , vital:72945 , https://doi.org/10.1145/1292491.1292493
- Description: We propose a probabilistic movement model for controlling ant-like agents foraging between two points. Such agents are all identical, simple, autonomous and can only communicate indirectly through the environment. These agents secrete two types of pheromone, one to mark trails towards the goal and another to mark trails back to the starting point. Three pheromone perception strategies are proposed (Strategy A, B and C). Agents that use strategy A perceive the desirability of a neighbouring location as the difference between levels of attractive and repulsive pheromone in that location. With strategy B, agents perceive the desirability of a location as the quotient of levels of attractive and repulsive pheromone. Agents using strategy C determine the product of the levels of attractive pheromone with the complement of levels of repulsive pheromone. We conduct experiments to confirm directionality as emergent property of trails formed by agents that use each strategy. In addition, we compare path formation speed and the quality of the formed path under changes in the environment. We also investigate each strategy's robustness in environments that contain obstacles. Finally, we investigate how adaptive each strategy is when obstacles are eventually removed from the scene and find that the best strategy of these three is strategy A. Such a strategy provides useful guidelines to researchers in further applications of swarm intelligence metaphors for complex problem solving.
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- Date Issued: 2007
An inexpensive geometrical micrometer for measuring small, live insects quickly without harming them
- Authors: Villet, Martin H
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441860 , vital:73928 , https://doi.org/10.1111/j.1570-7458.2006.00520.x
- Description: The article discusses the technical note for the journal" Entomologia Experimentalis et Applicata," in the first quarter of 2007 issue. The author provides information about an inexpensive geometrical micrometer for measuring small, live insects rapidly and accurately without causing harm to the organism. The method he applied for making the measurements is related to the wedge micrometer as described by the scientist SD Porter in 1983.
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- Date Issued: 2007
An ontology-based, multi-modal platform for the inclusion of marginalized rural communities into the knowledge society
- Authors: Thinyane, Mamello , Dalvit, Lorenzo , Slay, Hannah , Mapi, Thandeka , Terzoli, Alfredo
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431218 , vital:72755 , https://doi.org/10.1145/1292491.1292508
- Description: With the information revolution that promises to shape the 21st century, knowledge has become the prime commodity, very much like land, means of production and capital have been at different times in the past. Access to information, made instantly available by the growth of the Internet, determines access to economic resources, social participa-tion and better quality of life. For this reason, the knowledge stored on the Web and the advantages offered by the spread of Information and Communication Technology (ICT) are equally important for rich socie-ties to prosper and for poor ones to develop. The only difference is that marginalised communities do not have access to the tools and have little control over the content found in the domain of ICTs. In this paper we describe an intervention to develop the potential of a typical rural community in South Africa through ICTs. This involves providing Inter-net connectivity and deploying a platform to support e-commerce, e-learning, e-government and e-health. The core of the platform is an on-tology-based model designed to integrate and respond to Indigenous Knowledge Systems. This has been achieved by combining a deep understanding of local knowledge and social networks with the use of authoring, communication and ontology-management tools. The prima-ry goal of this new approach is to find a way to make ICT solutions more sensitive to the local context, and therefore more effective. Sec-ondly, we hope to foster a sense of ownership of the project among the community, by capitalising on local knowledge and resources.
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- Date Issued: 2007
Animated feather coats using field lines
- Authors: Bangay, Shaun D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433338 , vital:72963 , https://doi.org/10.1145/1294685.1294713
- Description: The tedious task of manually placing feathers on computer animated ob-jects involves aligning feathers, ensuring that they do not insect each other or penetrate the surface, deforming every feather to match the local surface features, and ensuring that the feather coat is consistent when the underly-ing object is animated. We present a technique for generating a feather coat over an object. Feather orientation is specified quickly and easily, feathers are deformed while ensuring collision prevention, and the coat can be ani-mated. We create a vector field in the space surrounding the body object and deform feathers to align with the field lines. The non-intersection proper-ty of the field lines ensures that feather intersections are avoided. We pro-vide a formulation of a suitable vector field and demonstrate that it is capa-ble of producing realistic feather coats. The process can easily be integrated into the work-flow of standard modelling and animation processes. We show examples of feather coat creation on a range of objects, proving that field line based placement of feather coats provides the desired functionality for feather modelling and animation.
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- Date Issued: 2007
Assessing the effects of invasive alien species on rural livelihoods: Case examples and a framework from South Africa
- Authors: Shackleton, Charlie M , McGarry, Dylan K , Fourie, Saskia , Gambiza, James , Shackleton, Sheona E , Fabricius, Christo
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181279 , vital:43715 , xlink:href="https://doi.org/10.1007/s10745-006-9095-0"
- Description: The detrimental impacts of invasive alien species (IAS) on ecosystem goods and services and local and regional economies are well documented. However, the use of IAS by rural communities is little understood, and rarely factored into IAS control programmes. Understanding the use of IAS by rural communities and factoring these into cost-benefit models is complex, depending upon a range of local-level attributes such as the time since invasion, abundance, and local-level costs and benefits. This paper reports on two case studies examining the role of IAS in rural livelihoods in the Eastern Cape, South Africa. In both cases, rural communities made widespread consumptive use of the IAS and generally would prefer higher densities, except in certain key localities. Several households traded in IAS products to generate supplementary income. We present a conceptual framework to guide interpretation of these and future case studies, considering attributes such as time since invasion, the competitiveness of the species, and the relative costs and benefits.
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- Date Issued: 2007