Additional morphological characteristics of Olive Thrushes and Karoo Thrushes
- Bonnevie, Bo T, Craig, Adrian J F K, Hulley, Patrick E
- Authors: Bonnevie, Bo T , Craig, Adrian J F K , Hulley, Patrick E
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447712 , vital:74669 , https://www.tandfonline.com/doi/pdf/10.2989/00306520409485415
- Description: A southern race of the Olive Thrush, Turdus olivaceus smithi Bonaparte, has recently been proposed as a full species, the Karoo Thrush Turdus smithi (Bowie et al. 2003). Some of the published information on the Olive Thrush Turdus olivaceus olivaceus thus pertains to the Karoo Thrush (eg Kopij 2000), whereas other information deals specifically with the Olive Thrush (eg Winterbottom 1966, Bonnevie et al. 2003). We have ringed, recaptured and recovered both Olive and Karoo Thrushes in the Eastern Cape since 1986, and the two taxa are markedly different in this region. We describe some differences in appearance of the two populations from these data, and compare mass and wing length of living birds, as well as culmen and tarsus lengths of museum specimens from the East London Museum, South Africa. The collection sites of the museum specimens were mapped using ArcView 3.1 (ESRI 1996) together with the ringing sites (Figure 1). Areas of potential sympatry are Oudtshoorn (33 25’S, 22 11’E) and Patensie (33 45’S, 24 48’E).
- Full Text:
- Authors: Bonnevie, Bo T , Craig, Adrian J F K , Hulley, Patrick E
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447712 , vital:74669 , https://www.tandfonline.com/doi/pdf/10.2989/00306520409485415
- Description: A southern race of the Olive Thrush, Turdus olivaceus smithi Bonaparte, has recently been proposed as a full species, the Karoo Thrush Turdus smithi (Bowie et al. 2003). Some of the published information on the Olive Thrush Turdus olivaceus olivaceus thus pertains to the Karoo Thrush (eg Kopij 2000), whereas other information deals specifically with the Olive Thrush (eg Winterbottom 1966, Bonnevie et al. 2003). We have ringed, recaptured and recovered both Olive and Karoo Thrushes in the Eastern Cape since 1986, and the two taxa are markedly different in this region. We describe some differences in appearance of the two populations from these data, and compare mass and wing length of living birds, as well as culmen and tarsus lengths of museum specimens from the East London Museum, South Africa. The collection sites of the museum specimens were mapped using ArcView 3.1 (ESRI 1996) together with the ringing sites (Figure 1). Areas of potential sympatry are Oudtshoorn (33 25’S, 22 11’E) and Patensie (33 45’S, 24 48’E).
- Full Text:
Applied aquatic ecotoxicology sub-lethal methods, whole effluent testing and communication
- Palmer, Carolyn G, Muller, Nikite W J, Davies-Coleman, Heather D
- Authors: Palmer, Carolyn G , Muller, Nikite W J , Davies-Coleman, Heather D
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437785 , vital:73409 , ISBN 1-77005-252-6 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/1245-1-041.pdf
- Description: This report is the most recent in a series of WRC reports on the development of the capacity to undertake ecotoxicological research in South Africa. The development followed the following tines: • Recognition, as a result of the Kruger National Park Rivers Research Programme, that there were virtually no data on the water quality requirements of South African macroin vertebrates. • Development of the capacity to undertake experimental tolerance testing using riverine invertebrates in artificial stream systems. • Investigation of the salt tolerances, and whole effluent toxicity responses, of both standard toxicity test taxa and South African macroinverte-brates. • Development of both lethal and sub-lethal measures. • Application of re-search results to the development of methods for water quality within ecological Reserve determinations, and the implementation of the National Water Act (NWA) (No 36. of 1998) and National Water Resource Strategy (NWRS). The WRC is com-mitted to funding research that underpins the implementation of the NWA and the NWRS. Over the past 12 years it became clear that there would not be a rapid up-take of ecotoxicology research results in South Africa, and that it was important to place ecotoxicology in the wider context of water quality. From this recognition, the concept of Environmental Water Quality evolved.
- Full Text:
- Authors: Palmer, Carolyn G , Muller, Nikite W J , Davies-Coleman, Heather D
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437785 , vital:73409 , ISBN 1-77005-252-6 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/1245-1-041.pdf
- Description: This report is the most recent in a series of WRC reports on the development of the capacity to undertake ecotoxicological research in South Africa. The development followed the following tines: • Recognition, as a result of the Kruger National Park Rivers Research Programme, that there were virtually no data on the water quality requirements of South African macroin vertebrates. • Development of the capacity to undertake experimental tolerance testing using riverine invertebrates in artificial stream systems. • Investigation of the salt tolerances, and whole effluent toxicity responses, of both standard toxicity test taxa and South African macroinverte-brates. • Development of both lethal and sub-lethal measures. • Application of re-search results to the development of methods for water quality within ecological Reserve determinations, and the implementation of the National Water Act (NWA) (No 36. of 1998) and National Water Resource Strategy (NWRS). The WRC is com-mitted to funding research that underpins the implementation of the NWA and the NWRS. Over the past 12 years it became clear that there would not be a rapid up-take of ecotoxicology research results in South Africa, and that it was important to place ecotoxicology in the wider context of water quality. From this recognition, the concept of Environmental Water Quality evolved.
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Catalytic activity of iron and cobalt phthalocyanine complexes towards the oxidation of cyclohexene using tert-butylhydroperoxide and chloroperoxybenzoic acid
- Sehlotho, Nthapo, Nyokong, Tebello
- Authors: Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290257 , vital:56729 , xlink:href="https://doi.org/10.1016/j.molcata.2003.08.014"
- Description: Cyclohexene oxidation using tert-butylhydroperoxide (TBHP) or chloroperoxybenzoic acid (CPBA) in the presence of iron(II) polychlorophthalocyanine (Cl16PcFe), iron(II) phthalocyanine (PcFe) and cobalt(II) phthalocyanine (PcCo), results in the formation of the following products: cyclohexene oxide, 2-cyclohexene-1-ol and 2-cyclohexene-1-one. Adipic acid was also formed after long reaction times. The selectivity for 2-cyclohexene-1-one is favoured when Cl16PcFe or PcCo catalysts are employed, while PcFe is selective towards the formation of 2-cyclohexene-1-ol. The Cl16PcFe catalyst is transformed into a μ-oxo dimer (Cl16PcFeIIIOIIIFePcCl16) during the oxidation process. The catalytic process using the unsubstituted PcCoII and PcFeII catalysts involved PcMIII species as an intermediate. The active form of the Cl16PcFe catalyst was stable to degradation in that it was still active even after 4 weeks of continued catalysis.
- Full Text:
- Authors: Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290257 , vital:56729 , xlink:href="https://doi.org/10.1016/j.molcata.2003.08.014"
- Description: Cyclohexene oxidation using tert-butylhydroperoxide (TBHP) or chloroperoxybenzoic acid (CPBA) in the presence of iron(II) polychlorophthalocyanine (Cl16PcFe), iron(II) phthalocyanine (PcFe) and cobalt(II) phthalocyanine (PcCo), results in the formation of the following products: cyclohexene oxide, 2-cyclohexene-1-ol and 2-cyclohexene-1-one. Adipic acid was also formed after long reaction times. The selectivity for 2-cyclohexene-1-one is favoured when Cl16PcFe or PcCo catalysts are employed, while PcFe is selective towards the formation of 2-cyclohexene-1-ol. The Cl16PcFe catalyst is transformed into a μ-oxo dimer (Cl16PcFeIIIOIIIFePcCl16) during the oxidation process. The catalytic process using the unsubstituted PcCoII and PcFeII catalysts involved PcMIII species as an intermediate. The active form of the Cl16PcFe catalyst was stable to degradation in that it was still active even after 4 weeks of continued catalysis.
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Determination of 2′, 3′-Dideoxyinosine Using Iron (II) Phthalocyanine Modified Carbon Paste Electrode
- Ozoemena, Kenneth I, Stefan, Raluca-Ioana, Nyokong, Tebello
- Authors: Ozoemena, Kenneth I , Stefan, Raluca-Ioana , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300298 , vital:57914 , xlink:href="https://doi.org/10.1081/AL-200031940"
- Description: An amperometric sensor, based on carbon paste impregnated with iron (II) phthalocyanine complex (FePc), has been constructed for the assay of anti‐HIV agent dideoxyinosine (didanosine, DDI). Using chronoamperometry (E = +1.04 V versus Ag/AgCl) technique, the amperometric sensor can be used reliably for dideoxyinosine assay at pH 7.4 phosphate buffer in the 1.5–9.5 nmol/L concentration range with a detection limit of 5.7 × 10−10 mol/L. The surface of the electrode can easily be regenerated by simple polishing, obtaining a fresh surface ready for use in a new assay. The new amperometric sensor proved to be highly reliable for the assay of dideoxyinosine purity in raw material as well as for the uniformity content test of Videx® tablets.
- Full Text:
- Authors: Ozoemena, Kenneth I , Stefan, Raluca-Ioana , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300298 , vital:57914 , xlink:href="https://doi.org/10.1081/AL-200031940"
- Description: An amperometric sensor, based on carbon paste impregnated with iron (II) phthalocyanine complex (FePc), has been constructed for the assay of anti‐HIV agent dideoxyinosine (didanosine, DDI). Using chronoamperometry (E = +1.04 V versus Ag/AgCl) technique, the amperometric sensor can be used reliably for dideoxyinosine assay at pH 7.4 phosphate buffer in the 1.5–9.5 nmol/L concentration range with a detection limit of 5.7 × 10−10 mol/L. The surface of the electrode can easily be regenerated by simple polishing, obtaining a fresh surface ready for use in a new assay. The new amperometric sensor proved to be highly reliable for the assay of dideoxyinosine purity in raw material as well as for the uniformity content test of Videx® tablets.
- Full Text:
Early development of water quality methods and approaches in ecological Reserve assessments
- Palmer, Carolyn G, Scherman, Patricia, Muller, Nikite W J, Rossouw, J N, Malan, H L, Jooste, S
- Authors: Palmer, Carolyn G , Scherman, Patricia , Muller, Nikite W J , Rossouw, J N , Malan, H L , Jooste, S
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437840 , vital:73416 , ISBN 1-77005-227-5 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/1108-1-041.pdf
- Description: This project was initiated in 2000 to allow the ecological Reserve team for water quality to undertake additional research while working on eco-logical Reserve determinations funded by the Department of Water Af-fairs and Forestry. The results of this work form the basis of the meth-ods reported in the Water Research Commission report Hughes DA (Ed)(in press).
- Full Text:
- Authors: Palmer, Carolyn G , Scherman, Patricia , Muller, Nikite W J , Rossouw, J N , Malan, H L , Jooste, S
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437840 , vital:73416 , ISBN 1-77005-227-5 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/1108-1-041.pdf
- Description: This project was initiated in 2000 to allow the ecological Reserve team for water quality to undertake additional research while working on eco-logical Reserve determinations funded by the Department of Water Af-fairs and Forestry. The results of this work form the basis of the meth-ods reported in the Water Research Commission report Hughes DA (Ed)(in press).
- Full Text:
Electrochemical and catalytic properties of chromium tetraaminophthalocyanine
- Obirai, Joe, Nyokong, Tebello
- Authors: Obirai, Joe , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300310 , vital:57915 , xlink:href="https://doi.org/10.1016/j.jelechem.2004.06.026"
- Description: Chromium tetraaminophthalocyanine (CrIIITAPc) has been synthesized and its electrochemical and spectroelectrochemical properties reported. The first reduction and oxidation in this complex occur at the central metal, giving CrIITAPc and CrIVTAPc complexes, respectively, the latter having been observed for the first time. The CrIIITAPc species was polymerized onto glassy carbon (GCE) or indium tin oxide (ITO) electrodes and the polymer evolution confirmed by UV/Visible spectroscopy and by scanning electron microscopy. The polymers were employed for the catalytic oxidation of nitrite or nitric oxide, and the catalysis involved the CrIVTAPc−1 species.
- Full Text:
- Authors: Obirai, Joe , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300310 , vital:57915 , xlink:href="https://doi.org/10.1016/j.jelechem.2004.06.026"
- Description: Chromium tetraaminophthalocyanine (CrIIITAPc) has been synthesized and its electrochemical and spectroelectrochemical properties reported. The first reduction and oxidation in this complex occur at the central metal, giving CrIITAPc and CrIVTAPc complexes, respectively, the latter having been observed for the first time. The CrIIITAPc species was polymerized onto glassy carbon (GCE) or indium tin oxide (ITO) electrodes and the polymer evolution confirmed by UV/Visible spectroscopy and by scanning electron microscopy. The polymers were employed for the catalytic oxidation of nitrite or nitric oxide, and the catalysis involved the CrIVTAPc−1 species.
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Electrochemical studies of manganese tetraamminophthalocyanine monomer and polymer
- Obirai, Joseph, Nyokong, Tebello
- Authors: Obirai, Joseph , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290330 , vital:56738 , xlink:href="https://doi.org/10.1016/j.electacta.2003.11.006"
- Description: Manganese tetraaminophthalocyanine (MnTAPc) has been synthesised. The cyclic voltammetry and spectroelectrochemistry of the complex have been examined. Spectroelectrochemistry has been used to confirm that the species synthesised in this work contains MnIII, giving (OH)MnIIITAPc. The oxidation and reduction couples obtained from cyclic voltammetry have been assigned to MnIVPc−/MnIVPc2− (couple I), MnIVPc2−/MnIIIPc2− (couple I′), MnIIIPc2−/MnIIPc2− (couple II) and MnIIPc2−/MnIIPc3− (couple III). Electropolymerization of the MnTAPc onto either the indium tin oxide or glassy carbon electrode results in the in the formation of a poly-MnTAPc. The poly-MnTAPc shows improved reversibility at low pH. The poly-MnTAPc electrode was employed to analyse glycine.
- Full Text:
- Authors: Obirai, Joseph , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290330 , vital:56738 , xlink:href="https://doi.org/10.1016/j.electacta.2003.11.006"
- Description: Manganese tetraaminophthalocyanine (MnTAPc) has been synthesised. The cyclic voltammetry and spectroelectrochemistry of the complex have been examined. Spectroelectrochemistry has been used to confirm that the species synthesised in this work contains MnIII, giving (OH)MnIIITAPc. The oxidation and reduction couples obtained from cyclic voltammetry have been assigned to MnIVPc−/MnIVPc2− (couple I), MnIVPc2−/MnIIIPc2− (couple I′), MnIIIPc2−/MnIIPc2− (couple II) and MnIIPc2−/MnIIPc3− (couple III). Electropolymerization of the MnTAPc onto either the indium tin oxide or glassy carbon electrode results in the in the formation of a poly-MnTAPc. The poly-MnTAPc shows improved reversibility at low pH. The poly-MnTAPc electrode was employed to analyse glycine.
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Emerging patterns of abstraction in environmental education: A review of materials, methods and professional development perspectives
- O'Donoghue, Rob B, Russo, Vladimir
- Authors: O'Donoghue, Rob B , Russo, Vladimir
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/373610 , vital:66707 , xlink:href="https://doi.org/10.1080/1350462042000258170"
- Description: The epistemic unconscious is the history of the field. And it is clear that, to secure some chance of really knowing what one is doing, one has to unfold what is inscribed in the various relations of implication in which the thinker and his thoughts are caught up, that is, the presuppositions he engages and the inclusions and exclusions he unwittingly performs. (Bourdieu, 2000, p. 99).
- Full Text:
- Authors: O'Donoghue, Rob B , Russo, Vladimir
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/373610 , vital:66707 , xlink:href="https://doi.org/10.1080/1350462042000258170"
- Description: The epistemic unconscious is the history of the field. And it is clear that, to secure some chance of really knowing what one is doing, one has to unfold what is inscribed in the various relations of implication in which the thinker and his thoughts are caught up, that is, the presuppositions he engages and the inclusions and exclusions he unwittingly performs. (Bourdieu, 2000, p. 99).
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Environmental education research and social change: Southern African perspectives
- Authors: Lotz-Sisitka, Heila
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182709 , vital:43855 , xlink:href="https://doi.org/10.1080/1350462042000258143"
- Description: Environmental issues and risks in southern Africa have, like elsewhere in the world, their roots in the structures and orientations of modern societies. In modernist fashion, we draw on education and research to address socio-ecological concerns. In 1995 Eureta Janse van Rensburg, then Murray and Roberts Chair of Environmental Education at Rhodes University,1 undertook a study to identify environmental education research priorities, and through her study she provided a description of research in environmental education as a ‘landscape of shifting priorites’ (Janse van Rensburg, 1995). The papers in this journal offer a contemporary ‘snapshot’ of the landscape of environmental education research in southern Africa, illustrating a fresh range of ‘shifting priorities’.
- Full Text:
- Authors: Lotz-Sisitka, Heila
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182709 , vital:43855 , xlink:href="https://doi.org/10.1080/1350462042000258143"
- Description: Environmental issues and risks in southern Africa have, like elsewhere in the world, their roots in the structures and orientations of modern societies. In modernist fashion, we draw on education and research to address socio-ecological concerns. In 1995 Eureta Janse van Rensburg, then Murray and Roberts Chair of Environmental Education at Rhodes University,1 undertook a study to identify environmental education research priorities, and through her study she provided a description of research in environmental education as a ‘landscape of shifting priorites’ (Janse van Rensburg, 1995). The papers in this journal offer a contemporary ‘snapshot’ of the landscape of environmental education research in southern Africa, illustrating a fresh range of ‘shifting priorities’.
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Environmental water quality in water resources management
- Palmer, Carolyn G, Berold, Robert, Muller, Nikite W J
- Authors: Palmer, Carolyn G , Berold, Robert , Muller, Nikite W J
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437611 , vital:73397 , ISBN 1-77005-083-3 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/TT217-04.pdf
- Description: This book will help anyone working with water resources to make decisions about water quality, specifically environmental aspects of water quality. The book ex-plores the balance between water resource protection and water resource use, with a particular focus on water quality. A balance is necessary because the National Wa-ter Act (NWA) requires that water resources be protected and managed to meet the water quality requirements of ecosystems. At the same time the Act also requires that water be used for social and economic benefit.
- Full Text:
- Authors: Palmer, Carolyn G , Berold, Robert , Muller, Nikite W J
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437611 , vital:73397 , ISBN 1-77005-083-3 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/TT217-04.pdf
- Description: This book will help anyone working with water resources to make decisions about water quality, specifically environmental aspects of water quality. The book ex-plores the balance between water resource protection and water resource use, with a particular focus on water quality. A balance is necessary because the National Wa-ter Act (NWA) requires that water resources be protected and managed to meet the water quality requirements of ecosystems. At the same time the Act also requires that water be used for social and economic benefit.
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Harvesting impacts on commonly used medicinal tree species (Catha edulis and Rapanea melanophloeos) under different land management regimes in the Mpumalanga Lowveld, South Africa
- Botha, Jenny, Witkowski, Ed T F, Shackleton, Charlie M
- Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181379 , vital:43728 , xlink:href="https://doi.org/10.4102/koedoe.v47i2.77"
- Description: Harvesting of products from plants in the wild is widespread throughout southern Africa. Particularly important products are plant parts used in traditional medicine. However, the impacts of harvesting practices are rarely quantified, with as yet insufficient generic rules across species and life forms. This limits the predictive ability to monitor and manage the affected populations. This paper examines the harvesting impact on two popular woody medicinal species used throughout sub-Saharan Africa, namely Catha edulis (Vahl) Forssk. ex Endl. (bushman’s tea) and Rapanea melanophloeos (L.) Mez. (Cape beech). In both species, basal diameters, heights, and the number of size classes in the harvested populations were lower than in unharvested. Densities of harvested populations were higher in both species, including densities of young plants, but the frequency of individuals in larger size classes was lower. The populations of both species being harvested for medicinal products appeared to be withstanding the current levels of harvesting, but the population structure of C. edulis populations being harvested for poles on the roadside and near human settlements had been substantially altered. Despite the resilience of the two species to harvesting for medicinal products, loss of habitat or changes in land use pose a threat to a number of the assessed populations.
- Full Text:
- Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181379 , vital:43728 , xlink:href="https://doi.org/10.4102/koedoe.v47i2.77"
- Description: Harvesting of products from plants in the wild is widespread throughout southern Africa. Particularly important products are plant parts used in traditional medicine. However, the impacts of harvesting practices are rarely quantified, with as yet insufficient generic rules across species and life forms. This limits the predictive ability to monitor and manage the affected populations. This paper examines the harvesting impact on two popular woody medicinal species used throughout sub-Saharan Africa, namely Catha edulis (Vahl) Forssk. ex Endl. (bushman’s tea) and Rapanea melanophloeos (L.) Mez. (Cape beech). In both species, basal diameters, heights, and the number of size classes in the harvested populations were lower than in unharvested. Densities of harvested populations were higher in both species, including densities of young plants, but the frequency of individuals in larger size classes was lower. The populations of both species being harvested for medicinal products appeared to be withstanding the current levels of harvesting, but the population structure of C. edulis populations being harvested for poles on the roadside and near human settlements had been substantially altered. Despite the resilience of the two species to harvesting for medicinal products, loss of habitat or changes in land use pose a threat to a number of the assessed populations.
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Integrating indigenous ecological knowledge and customary sea tenure with marine and social science for conservation of bumphead parrotfish (Bolbometopon muricatum) in the Roviana Lagoon, Solomon Islands
- Shankar, Aswani, Hamilton, Richard
- Authors: Shankar, Aswani , Hamilton, Richard
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439945 , vital:73722 , xlink:href="https://doi.org/10.1017/S037689290400116X"
- Description: Indigenous ecological knowledge and customary sea tenure may be integrated with marine and social science to conserve the bumphead parrotfish (Bolbometopon muricatum) in the Roviana Lagoon, Western Solomon Islands. Three aspects of indigenous ecological knowledge in Roviana were identified as most relevant for the management and conservation of bumphead parrotfish, and studied through a combination of marine science and anthropological methods. These were (1) local claims that fishing pressure has had a significant impact on bumphead parrotfish populations in the Roviana Lagoon; (2) the claim that only small bumphead parrotfish were ever seen or captured in the inner lagoon and that very small fish were restricted to specific shallow inner-lagoon nursery regions; and (3) assertions made by local divers that bumphead parrotfish predominantly aggregated at night around the new moon period and that catches were highest at that time. The research supported claims (1) and (2), but did not support proposition (3). Although the people of the Roviana Lagoon had similar conceptions about their entitlement rights to sea space, there were marked differences among regional villages in their opinions regarding governance and actual operational rules of management in the Lagoon. Contemporary differences in management strategies resulted from people's historical and spatial patterns of settlement across the landscape and adjoining seascapes, and the attendant impact of these patterns on property relations. This was crucial in distinguishing between those villages that held secure tenure over their contiguous sea estates from those that did not. Indigenous ecological knowledge served to (1) verify that the bumphead parrotfish was a species in urgent need of protection; (2) explain how different habitats structured the size distribution of bumphead parrotfish; (3) identify sensitive locations and habitats in need of protection; and (4) explain the effect of lunar periodicity on bumphead parrotfish behaviour and catch rates. Secure customary sea tenure identified locations best suited to bumphead parrotfish management programmes, with a greater likelihood for local participation and programme success. The information was used to establish two marine protected areas in the region for bumphead parrotfish conservation.
- Full Text:
- Authors: Shankar, Aswani , Hamilton, Richard
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439945 , vital:73722 , xlink:href="https://doi.org/10.1017/S037689290400116X"
- Description: Indigenous ecological knowledge and customary sea tenure may be integrated with marine and social science to conserve the bumphead parrotfish (Bolbometopon muricatum) in the Roviana Lagoon, Western Solomon Islands. Three aspects of indigenous ecological knowledge in Roviana were identified as most relevant for the management and conservation of bumphead parrotfish, and studied through a combination of marine science and anthropological methods. These were (1) local claims that fishing pressure has had a significant impact on bumphead parrotfish populations in the Roviana Lagoon; (2) the claim that only small bumphead parrotfish were ever seen or captured in the inner lagoon and that very small fish were restricted to specific shallow inner-lagoon nursery regions; and (3) assertions made by local divers that bumphead parrotfish predominantly aggregated at night around the new moon period and that catches were highest at that time. The research supported claims (1) and (2), but did not support proposition (3). Although the people of the Roviana Lagoon had similar conceptions about their entitlement rights to sea space, there were marked differences among regional villages in their opinions regarding governance and actual operational rules of management in the Lagoon. Contemporary differences in management strategies resulted from people's historical and spatial patterns of settlement across the landscape and adjoining seascapes, and the attendant impact of these patterns on property relations. This was crucial in distinguishing between those villages that held secure tenure over their contiguous sea estates from those that did not. Indigenous ecological knowledge served to (1) verify that the bumphead parrotfish was a species in urgent need of protection; (2) explain how different habitats structured the size distribution of bumphead parrotfish; (3) identify sensitive locations and habitats in need of protection; and (4) explain the effect of lunar periodicity on bumphead parrotfish behaviour and catch rates. Secure customary sea tenure identified locations best suited to bumphead parrotfish management programmes, with a greater likelihood for local participation and programme success. The information was used to establish two marine protected areas in the region for bumphead parrotfish conservation.
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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.
- Full Text:
- 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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Kaleidoscope configurations for reflectance measurement
- Bangay, Shaun D, Radloff, Judith D
- Authors: Bangay, Shaun D , Radloff, Judith D
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432891 , vital:72910 , https://doi.org/10.1145/1029949.1029979
- Description: Simulations of different configurations of the symmetrical tapered kaleidoscope are performed to assess their merits for measurement of BRDFs and BTFs. The relationship between optimal kaleidoscope layout, and factors such as hardware restrictions and the resolution of the required reflectance function, is derived. The effect on the measurement of the reflectance function of changing these independent variables is examined through the simulation. These experiments highlight issues affecting the measurement of BTFs using kaleidoscopes, and suggest configurations that allow sampling at regular parameter intervals. A number of other kaleidoscope architectures are explored, which offer the benefits of potentially doubling the range of directions that can be sampled, and allowing adaptive control of sample intervals.
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- Authors: Bangay, Shaun D , Radloff, Judith D
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432891 , vital:72910 , https://doi.org/10.1145/1029949.1029979
- Description: Simulations of different configurations of the symmetrical tapered kaleidoscope are performed to assess their merits for measurement of BRDFs and BTFs. The relationship between optimal kaleidoscope layout, and factors such as hardware restrictions and the resolution of the required reflectance function, is derived. The effect on the measurement of the reflectance function of changing these independent variables is examined through the simulation. These experiments highlight issues affecting the measurement of BTFs using kaleidoscopes, and suggest configurations that allow sampling at regular parameter intervals. A number of other kaleidoscope architectures are explored, which offer the benefits of potentially doubling the range of directions that can be sampled, and allowing adaptive control of sample intervals.
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Linda implementations in Java for concurrent systems
- Wells, George C, Chalmers, A G, Clayton, Peter G
- Authors: Wells, George C , Chalmers, A G , Clayton, Peter G
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430555 , vital:72699 , https://doi.org/10.1002/cpe.794
- Description: This paper surveys a number of the implementations of Linda that are available in Java. It provides some discussion of their strengths and weaknesses, and pre-sents the results from benchmarking experiments using a network of commodity workstations. Some extensions to the original Linda programming model are also presented and discussed, together with examples of their application to parallel processing problems.
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- Authors: Wells, George C , Chalmers, A G , Clayton, Peter G
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430555 , vital:72699 , https://doi.org/10.1002/cpe.794
- Description: This paper surveys a number of the implementations of Linda that are available in Java. It provides some discussion of their strengths and weaknesses, and pre-sents the results from benchmarking experiments using a network of commodity workstations. Some extensions to the original Linda programming model are also presented and discussed, together with examples of their application to parallel processing problems.
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Modelling and rendering techniques for african hairstyles
- Patrick, Deborah, Bangay, Shaun D, Lobb, Adele
- Authors: Patrick, Deborah , Bangay, Shaun D , Lobb, Adele
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432905 , vital:72911 , https://doi.org/10.1145/1029949.1029971
- Description: We develop or enhance hair modelling and rendering techniques to produce three different forms of hair commonly found in African hairstyles. The forms of hair are natural curly hair, straightened hair, and braids or twists of hair. We use an implicit model, implemented as a series of textured layers to represent curly hair. Straightened hair is represented explicitly, and mod-elled by defining and replicating a few control hairs. Braids and twists are implemented as textured generalized cylinders. A synthesis of existing hair illumination models is used as a basis for an African hair illumination model. Parameter values to match African hair characteristics are discussed. A number of complete African hairstyles are shown, demonstrating that the techniques can be used to model and render African hair successfully.
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- Authors: Patrick, Deborah , Bangay, Shaun D , Lobb, Adele
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432905 , vital:72911 , https://doi.org/10.1145/1029949.1029971
- Description: We develop or enhance hair modelling and rendering techniques to produce three different forms of hair commonly found in African hairstyles. The forms of hair are natural curly hair, straightened hair, and braids or twists of hair. We use an implicit model, implemented as a series of textured layers to represent curly hair. Straightened hair is represented explicitly, and mod-elled by defining and replicating a few control hairs. Braids and twists are implemented as textured generalized cylinders. A synthesis of existing hair illumination models is used as a basis for an African hair illumination model. Parameter values to match African hair characteristics are discussed. A number of complete African hairstyles are shown, demonstrating that the techniques can be used to model and render African hair successfully.
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Oral tradition and the creation of late prehistory in Roviana Lagoon, Solomon Islands
- Sheppard, Peter, Walter, Richard, Aswani, Shankar
- Authors: Sheppard, Peter , Walter, Richard , Aswani, Shankar
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/439958 , vital:73723 , ISBN 0975047639
- Description: The use of oral tradition or oral history in archaeology is often a contentious issue. In this paper we briefly review methodological issues surrounding the use of such data and follow this with a case study using our research into the last 1,000 years of prehistory in Roviana Lagoon (New Georgia Group, Solomon Islands). We argue that it is not possible to generalize cross-culturally about the historicity of oral tradition/history. However, in the Roviana case, careful use of ethnohistory and archaeology together indicates that:(a) Roviana oral history is linear;(b) there is a close relationship between genealogical age and radiocarbon age; and (c) the modern uses of the oral tradition by Roviana provide a theory of their use in the past. We conclude that the model for the formation of the Roviana Chiefdom which emerges from the working back and forth between archaeology and ethnohistory has much more explanatory power than one based on either source of data by itself.
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- Authors: Sheppard, Peter , Walter, Richard , Aswani, Shankar
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/439958 , vital:73723 , ISBN 0975047639
- Description: The use of oral tradition or oral history in archaeology is often a contentious issue. In this paper we briefly review methodological issues surrounding the use of such data and follow this with a case study using our research into the last 1,000 years of prehistory in Roviana Lagoon (New Georgia Group, Solomon Islands). We argue that it is not possible to generalize cross-culturally about the historicity of oral tradition/history. However, in the Roviana case, careful use of ethnohistory and archaeology together indicates that:(a) Roviana oral history is linear;(b) there is a close relationship between genealogical age and radiocarbon age; and (c) the modern uses of the oral tradition by Roviana provide a theory of their use in the past. We conclude that the model for the formation of the Roviana Chiefdom which emerges from the working back and forth between archaeology and ethnohistory has much more explanatory power than one based on either source of data by itself.
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Parasitoids associated with the diamondback moth, Plutella xylostella (L.), in the Eastern Cape, South Africa
- Smith, Tamara J, Villet, Martin H
- Authors: Smith, Tamara J , Villet, Martin H
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , conference
- Identifier: http://hdl.handle.net/10962/442795 , vital:74034 , ISBN , https://www.cabidigitallibrary.org/doi/full/10.5555/20093098381
- Description: Seasonal fluctuations of diamondback moth and its hymenopteran parasitoids were recorded weekly from April 1997 to November 1999 at four cabbage sites in the Grahamstown area of the Eastern Cape, South Africa. Two sites were commercial farms with active spraying programmes; the others were unsprayed. Infestation levels were highest during spring (September to November) and autumn (March to May), where 100% infestation of plants was reached at times. The highest infestation was found during the spring months, where 12 larvae/plant were found at the unsprayed sites and between 6 and 10 larvae at the sprayed sites. At the unsprayed sites abundance of diamondback moth larvae and parasitoids was high during 1997, but much lower during 1998 and 1999, indicating possible control by the parasitoids. Nine species of parasitoid were recorded from diamondback moth during this period and four (Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae), Diadegma mollipla (Holmgren) (Hymenoptera: Ichneumonidae), Diadromus collaris Gravenhorst (Hymenoptera: Ichneumonidae) and Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae)) showed potential as biological control agents. The highest rate of parasitism was found from mid-autumn to the beginning of winter (April to June) and from mid-spring to the beginning of summer (October to December). Percent parasitism varied throughout the year, ranging between 10% and 80%. Parasitism of 100% was observed when moth numbers were low. Different species of parasitoids were found to be dominant at different times of the year.
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- Authors: Smith, Tamara J , Villet, Martin H
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , conference
- Identifier: http://hdl.handle.net/10962/442795 , vital:74034 , ISBN , https://www.cabidigitallibrary.org/doi/full/10.5555/20093098381
- Description: Seasonal fluctuations of diamondback moth and its hymenopteran parasitoids were recorded weekly from April 1997 to November 1999 at four cabbage sites in the Grahamstown area of the Eastern Cape, South Africa. Two sites were commercial farms with active spraying programmes; the others were unsprayed. Infestation levels were highest during spring (September to November) and autumn (March to May), where 100% infestation of plants was reached at times. The highest infestation was found during the spring months, where 12 larvae/plant were found at the unsprayed sites and between 6 and 10 larvae at the sprayed sites. At the unsprayed sites abundance of diamondback moth larvae and parasitoids was high during 1997, but much lower during 1998 and 1999, indicating possible control by the parasitoids. Nine species of parasitoid were recorded from diamondback moth during this period and four (Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae), Diadegma mollipla (Holmgren) (Hymenoptera: Ichneumonidae), Diadromus collaris Gravenhorst (Hymenoptera: Ichneumonidae) and Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae)) showed potential as biological control agents. The highest rate of parasitism was found from mid-autumn to the beginning of winter (April to June) and from mid-spring to the beginning of summer (October to December). Percent parasitism varied throughout the year, ranging between 10% and 80%. Parasitism of 100% was observed when moth numbers were low. Different species of parasitoids were found to be dominant at different times of the year.
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Quantification of the photosynthetic performance of phosphorus-deficient Sorghum by means of chlorophyll-a fluorescence kinetics
- Ripley, Bradley S, Redfern, Sally P, Dames, Joanna F
- Authors: Ripley, Bradley S , Redfern, Sally P , Dames, Joanna F
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440444 , vital:73783 , https://hdl.handle.net/10520/EJC96177
- Description: Chlorophyll fluorescence induction curves have been used as a sensitive tool for screening the photosynthetic performance of plants. Experimental treatments involving nitrate supply and chilling stress have been shown to affect fluorescence induction curves and other measures of photosynthesis. We have investigated the photosynthetic performance of Sorghum bicolor supplied with Long Ashton growth solution containing standard (20 mmol mol-1) or low (5 mmol mol-1) phosphorus. The JIP-test based on the chlorophyll fluorescence induction curve was used as a non-destructive method to measure the relative proportions of energy dissipated by different processes (termed energy fluxes) in the light reactions. The various energy fluxes or derived parameters were compared to find the measures that were most sensitive to the experimental conditions. Plant response to treatments was first evident in selected chlorophyll fluorescence parameters, particularly performance index (PIABS); plants with increased PIABS manifested higher electron transport activity and dissipated less energy as heat, possibly as a result of their better phosphorus status, leading to more functional reaction centres. Observed changes in fluorescence were correlated to changes in gas exchange and biomass. Standard phosphorus treatments significantly increased biomass, leaf area, photosynthetic and respiratory rates, carboxylation efficiencies and levels of ribulose biphosphate regeneration rates, relative to plants with low supplies of nutrients.
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- Authors: Ripley, Bradley S , Redfern, Sally P , Dames, Joanna F
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440444 , vital:73783 , https://hdl.handle.net/10520/EJC96177
- Description: Chlorophyll fluorescence induction curves have been used as a sensitive tool for screening the photosynthetic performance of plants. Experimental treatments involving nitrate supply and chilling stress have been shown to affect fluorescence induction curves and other measures of photosynthesis. We have investigated the photosynthetic performance of Sorghum bicolor supplied with Long Ashton growth solution containing standard (20 mmol mol-1) or low (5 mmol mol-1) phosphorus. The JIP-test based on the chlorophyll fluorescence induction curve was used as a non-destructive method to measure the relative proportions of energy dissipated by different processes (termed energy fluxes) in the light reactions. The various energy fluxes or derived parameters were compared to find the measures that were most sensitive to the experimental conditions. Plant response to treatments was first evident in selected chlorophyll fluorescence parameters, particularly performance index (PIABS); plants with increased PIABS manifested higher electron transport activity and dissipated less energy as heat, possibly as a result of their better phosphorus status, leading to more functional reaction centres. Observed changes in fluorescence were correlated to changes in gas exchange and biomass. Standard phosphorus treatments significantly increased biomass, leaf area, photosynthetic and respiratory rates, carboxylation efficiencies and levels of ribulose biphosphate regeneration rates, relative to plants with low supplies of nutrients.
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Scientific evaluation in women’s participatory management: monitoring marine invertebrate refugia in the Solomon Islands
- Authors: Shankar, Aswani , Weiant, P
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439983 , vital:73725 , xlink:href="https://doi.org/10.17730/humo.63.3.r7kgd4thktmyf7k1"
- Description: This paper summarizes the results of a women’s community-based marine protected area that has been successful in sustaining invertebrate biological resources and in promoting strong community support. We outline the project and the associated biological results, describe the processes involved in attaining a committed level of community participation, and review the lessons learned during the project’s implementation. We attribute the project’s preliminary success—improved shellfish biomass, enhanced local environmental awareness, and the reinvigoration of cultural management practices—to the following factors: 1) the high level of participatory involvement and community leadership; 2) the local perception that shell beds have recovered rapidly and the role that scientific evaluation has played in reinforcing this notion; 3) a research program that is cross-fertilizing indigenous and scientific ecological knowledge; 4) the unique marine tenure system that allows for the project’s development and the area’s policing; and 5) the tangible economic incentives created by the development project, which ultimately empowers local women. We hope that the project’s findings can be generalized to other regions of the world with operational sea-tenure regimes and that it can help to make the establishing of community-based marine protected areas (CBMPAs) across the Pacific region more effective.
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- Authors: Shankar, Aswani , Weiant, P
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439983 , vital:73725 , xlink:href="https://doi.org/10.17730/humo.63.3.r7kgd4thktmyf7k1"
- Description: This paper summarizes the results of a women’s community-based marine protected area that has been successful in sustaining invertebrate biological resources and in promoting strong community support. We outline the project and the associated biological results, describe the processes involved in attaining a committed level of community participation, and review the lessons learned during the project’s implementation. We attribute the project’s preliminary success—improved shellfish biomass, enhanced local environmental awareness, and the reinvigoration of cultural management practices—to the following factors: 1) the high level of participatory involvement and community leadership; 2) the local perception that shell beds have recovered rapidly and the role that scientific evaluation has played in reinforcing this notion; 3) a research program that is cross-fertilizing indigenous and scientific ecological knowledge; 4) the unique marine tenure system that allows for the project’s development and the area’s policing; and 5) the tangible economic incentives created by the development project, which ultimately empowers local women. We hope that the project’s findings can be generalized to other regions of the world with operational sea-tenure regimes and that it can help to make the establishing of community-based marine protected areas (CBMPAs) across the Pacific region more effective.
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