Kowie Engine at Port Alfred
- Subjects: Locomotives -- South Africa -- Port Alfred -- Photographs
- Type: Image
- Identifier: http://hdl.handle.net/10962/20522 , vital:22872 , PIC/M 274 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017.
- Description: Note on the bottom: “Kowie Engine” and “Port Alfred”. d. Note on the back: “The first two engines for 3’-6” gauge working between Port Alfred and Grahamstown Landed by SS Rothsay May 20th 1882 – Ran first trial trip from Port Alfred for 16 miles pn the 25th July 1882. Engine made my the Hunsletics & Leeds. The Kowie Engine was the passing engine [illegible] 22 Tom “Grahamstown” “Port Alfred” engine for Goods working washing 25 Tom or “Kowie”". , Kowie engine at Port Alfred.
- Full Text: false
- Subjects: Locomotives -- South Africa -- Port Alfred -- Photographs
- Type: Image
- Identifier: http://hdl.handle.net/10962/20522 , vital:22872 , PIC/M 274 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017.
- Description: Note on the bottom: “Kowie Engine” and “Port Alfred”. d. Note on the back: “The first two engines for 3’-6” gauge working between Port Alfred and Grahamstown Landed by SS Rothsay May 20th 1882 – Ran first trial trip from Port Alfred for 16 miles pn the 25th July 1882. Engine made my the Hunsletics & Leeds. The Kowie Engine was the passing engine [illegible] 22 Tom “Grahamstown” “Port Alfred” engine for Goods working washing 25 Tom or “Kowie”". , Kowie engine at Port Alfred.
- Full Text: false
Proposed bathing Pavilion for Port Alfred Municipality
- Date: 1922
- Subjects: f-sa , 1/8 = 1 foot 30.5595° S, 22.9375° E , Port Alfred (South Africa) Maps , South Africa History 1909-1961
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/124996 , vital:35717 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP665_3
- Description: Proposed bathing Pavilion for Port Alfred Municipality.
- Full Text: false
- Date Issued: 1922
- Date: 1922
- Subjects: f-sa , 1/8 = 1 foot 30.5595° S, 22.9375° E , Port Alfred (South Africa) Maps , South Africa History 1909-1961
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/124996 , vital:35717 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP665_3
- Description: Proposed bathing Pavilion for Port Alfred Municipality.
- Full Text: false
- Date Issued: 1922
Proposed buildings on Block no 2968 Port Alfred for F.H. Schoeder, Esqr.
- Date: 1922
- Subjects: f-sa , not available 30.5595° S, 22.9375° E , Port Alfred (South Africa) Maps , South Africa History 1909-1961
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/130722 , vital:36472 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP665_1
- Description: Proposed buildings on Block no 2968 Port Alfred for F.H. Schoeder, Esqr.
- Full Text: false
- Date Issued: 1922
- Date: 1922
- Subjects: f-sa , not available 30.5595° S, 22.9375° E , Port Alfred (South Africa) Maps , South Africa History 1909-1961
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/130722 , vital:36472 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP665_1
- Description: Proposed buildings on Block no 2968 Port Alfred for F.H. Schoeder, Esqr.
- Full Text: false
- Date Issued: 1922
Trans-oceanic and endemic origins of the small minnow mayflies (Ephemeroptera, Baetidae) of Madagascar
- Monaghan, M T, Gattolliat, J L, Sartori, Michel, Elouard, J M, Barber-James, Helen M, Derleth, P, Glaizot, Olivier, De Moor, Ferdy C, Vogler, Alfred P
- Authors: Monaghan, M T , Gattolliat, J L , Sartori, Michel , Elouard, J M , Barber-James, Helen M , Derleth, P , Glaizot, Olivier , De Moor, Ferdy C , Vogler, Alfred P
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6957 , http://hdl.handle.net/10962/d1011998
- Description: We investigated the relative importance of dispersal and vicariance in forming the Madagascar insect fauna, sequencing approximately 2300bp from three rRNA gene regions to investigate the phylogeny of Afrotropical small minnow mayflies (Ephemeroptera: Baetidae). Six lineages contained trans-oceanic sister taxa, and variation in genetic divergence between sister taxa revealed relationships that range from very recent dispersal to ancient vicariance. Dispersal was most recent and frequent in species that spend the larval stage in standing water, adding to evidence that these evolutionarily unstable habitats may select for ecological traits that increase dispersal in insects. Ancestral state likelihood analysis suggested at least one Afrotropical lineage had its origin in Madagascar, demonstrating that unidirectional dispersal from a continental source may be too simplistic. We conclude that the Malagasy mayfly fauna should be considered in a biogeographical context that extends beyond Madagascar itself, encompassing trans-oceanic dispersal within multiple lineages.
- Full Text:
- Date Issued: 2005
- Authors: Monaghan, M T , Gattolliat, J L , Sartori, Michel , Elouard, J M , Barber-James, Helen M , Derleth, P , Glaizot, Olivier , De Moor, Ferdy C , Vogler, Alfred P
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6957 , http://hdl.handle.net/10962/d1011998
- Description: We investigated the relative importance of dispersal and vicariance in forming the Madagascar insect fauna, sequencing approximately 2300bp from three rRNA gene regions to investigate the phylogeny of Afrotropical small minnow mayflies (Ephemeroptera: Baetidae). Six lineages contained trans-oceanic sister taxa, and variation in genetic divergence between sister taxa revealed relationships that range from very recent dispersal to ancient vicariance. Dispersal was most recent and frequent in species that spend the larval stage in standing water, adding to evidence that these evolutionarily unstable habitats may select for ecological traits that increase dispersal in insects. Ancestral state likelihood analysis suggested at least one Afrotropical lineage had its origin in Madagascar, demonstrating that unidirectional dispersal from a continental source may be too simplistic. We conclude that the Malagasy mayfly fauna should be considered in a biogeographical context that extends beyond Madagascar itself, encompassing trans-oceanic dispersal within multiple lineages.
- Full Text:
- Date Issued: 2005
Proposed extensions and alterations to Sea View Port Alfred East for A. Larsen Esq.
- Date: 19uu
- Subjects: f-sa , Not specified 30.5595° S, 22.9375° E , Port Alfred (South Africa) Maps , South Africa History 1909-1961
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/124975 , vital:35715 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP665_2
- Description: Proposed extensions and alterations to Sea View Port Alfred East for A. Larsen Esq. One of nine plans from the Scott Collection, 1922-1947.
- Full Text: false
- Date Issued: 19uu
- Date: 19uu
- Subjects: f-sa , Not specified 30.5595° S, 22.9375° E , Port Alfred (South Africa) Maps , South Africa History 1909-1961
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/124975 , vital:35715 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP665_2
- Description: Proposed extensions and alterations to Sea View Port Alfred East for A. Larsen Esq. One of nine plans from the Scott Collection, 1922-1947.
- Full Text: false
- Date Issued: 19uu
Plan of territories formerly known as Kaffraria proper
- Authors: Burton, Alfred William
- Date: 1884
- Subjects: Kaffraria Maps , South Africa History 1836-1909 Maps
- Language: English
- Type: maps , cartographic
- Identifier: http://hdl.handle.net/10962/115759 , vital:34227 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP1877
- Description: Plan of Territories formerly known as Kaffraria proper: simplified handdrawn copy of the 1884 map of the territories formerly known as Kaffraria, with additional information inserted by Alfred William Burton. Surveyors C.P. Watermeyer; Fletcher ; MacDonald, Schunke, Tilney, Norris, Greeff, Greathead, F. Watermeyer; Erskine, Hughes R.N., Changuion, Pritchard and O. Mehliss, and military sketches by Messrs Colley and Grant and the Intelligence Branch of the Quartermaster General's Department. Photocopy stuck on card. Transkeian territories. First produced in 1884 by 14 surveyors and 3 others.See MP 307, L (77) d 1 for the original map by fourteen surveyors and Military sketches.
- Full Text: false
- Date Issued: 1884
- Authors: Burton, Alfred William
- Date: 1884
- Subjects: Kaffraria Maps , South Africa History 1836-1909 Maps
- Language: English
- Type: maps , cartographic
- Identifier: http://hdl.handle.net/10962/115759 , vital:34227 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP1877
- Description: Plan of Territories formerly known as Kaffraria proper: simplified handdrawn copy of the 1884 map of the territories formerly known as Kaffraria, with additional information inserted by Alfred William Burton. Surveyors C.P. Watermeyer; Fletcher ; MacDonald, Schunke, Tilney, Norris, Greeff, Greathead, F. Watermeyer; Erskine, Hughes R.N., Changuion, Pritchard and O. Mehliss, and military sketches by Messrs Colley and Grant and the Intelligence Branch of the Quartermaster General's Department. Photocopy stuck on card. Transkeian territories. First produced in 1884 by 14 surveyors and 3 others.See MP 307, L (77) d 1 for the original map by fourteen surveyors and Military sketches.
- Full Text: false
- Date Issued: 1884
Synthesis and characterisation of lanthanide complexes with potential nitrogen- and oxygen-donor schiff base ligands
- Authors: Pikoli, Sibongile
- Date: 2020
- Subjects: Rare earths , Schiff bases
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47050 , vital:39778
- Description: This research describes the coordination chemistry of lanthanide complexes with potentially multidentate nitrogen- and oxygen-donor Schiff base derivatives. The studies were performed using various physico-chemical techniques including melting point, IR and NMR spectroscopy, UV-Vis spectroscopy, elemental analyses, conductivity measurements, X-ray crystallography and cyclic voltammetry. The reaction of [Ln(NO3)3·xH2O] (Ln = Nd, Gd, Yb; x = 6 for Nd and Gd, x = 5 for Yb) with the flexible salen-type Schiff base ligand 1,3-bis(o-hydroxybenzylideneamino)propane (H2L1) produced three polynuclear complexes with the general formulae {[Nd(µH2L1)4(NO3)3]·2H2O}n and [Ln(µ-H2L1)2(NO3)6(H2L1)] (Ln = Gd and Yb). Single-crystal Xray crystallography revealed a ten-coordinate polymeric Nd(III) complex that crystallised in the monoclinic space group P21/c, and isostructural nine-coordinate binuclear Gd(III) and Yb(III) complexes (triclinic system, space group P-1). The lanthanide contraction effect is clear across the series. The flexible nature of HL2 results in the self-assembly of the Nd(III) complex in a 1D polymer chain by acting as the bridge between the metal ions. The Nd-Ophenolate bond distances are 2.403(18), 2.463(17), 2.379(17) and 2.367(19) Å and the average Nd-Onitrate bond length is 2.671 Å. Furthermore, the electronic absorption spectra displays 4f→4f transitions solely for the neodymium(III) compound. The syntheses and characterisation of the lanthanide complexes, [La(HL2)3(NO3)3], [Dy(HL2)2(NO3)3] and [Dy(HL2)2Cl3(H2O)]·2CH2Cl2 with the o-vanillin-derived Schiff base ligand 2-methoxy-6-[(E)-(phenylimino)methyl]phenol (HL2) are reported. The nitro-stabilised La(III) and Dy(III) compounds are ten-coordinate with metabidiminished icosahedron and sphenocorona geometries, respectively. Substitution of the nitrate with chloride ions in the starting metal compounds yielded an eight-coordinate Dy(III) complex that adopts the biaugmented trigonal prism geometry. For all three complexes, HL2 exists as a zwitterion that is bound to the metal centre in a mono- and bidentate fashion via the phenolate and methoxy oxygen atoms. The dysprosium(III) chloride complex is stabilised by both intramolecular N−H···O and intermolecular O−H···C1 hydrogen bonds, while the crystal packing of the Ln(III) nitrate complexes is ensured by mainly intramolecular N−H···O hydrogen bonds. Fluorescence studies displayed characteristic Dy(III) f→f transitions (4F9/2 → 6H15/2), which suggest the ligand HL2 is an effective organic antenna to absorb and transfer energy to the dysprosium ion. A series of mononuclear Nd(III) complexes with the Schiff base derivatives 2-methoxy-6-[(E)(phenylimino)methyl]phenol (HL2), 5-methoxy-2-[(E)-(phenylimino)methyl]phenol (HL3) and 2-methoxy-6-{(E)-[(2-methoxyphenyl)imino]methyl}phenol (HL4) yielded structurally diverse complexes defined by the formulae [Nd(HL2)2(NO3)3], [Nd(HL3)3(NO3)3] and [Nd(HL4)2(NO3)3]·CH3OH. Crystallographic analysis shows HL2 and HL4 coordinate bidentately via the phenolate and methoxy oxygen atoms, while HL3 is bound monodentately through the phenolate oxygen atom. Continuous shape measures depict that the decacoordinate complexes with HL2 and HL4 conform to the sphenocorona and tetradecahedron geometries, respectively, whilst the nona-coordinate Nd(III) complex with HL3 exhibits the muffin geometry. The effect of the ligand substituents and their positions (meta versus para) on the absorption and emission intensities of the complexes is demonstrated. Additionally, the electrochemical behaviour of the o-vanillin-derived Schiff base ligands and their complexes was also investigated, and the results illustrate ligand-based reductions and metal-centred redox potentials that are significantly shifted by the ligand substituents.
- Full Text:
- Date Issued: 2020
- Authors: Pikoli, Sibongile
- Date: 2020
- Subjects: Rare earths , Schiff bases
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47050 , vital:39778
- Description: This research describes the coordination chemistry of lanthanide complexes with potentially multidentate nitrogen- and oxygen-donor Schiff base derivatives. The studies were performed using various physico-chemical techniques including melting point, IR and NMR spectroscopy, UV-Vis spectroscopy, elemental analyses, conductivity measurements, X-ray crystallography and cyclic voltammetry. The reaction of [Ln(NO3)3·xH2O] (Ln = Nd, Gd, Yb; x = 6 for Nd and Gd, x = 5 for Yb) with the flexible salen-type Schiff base ligand 1,3-bis(o-hydroxybenzylideneamino)propane (H2L1) produced three polynuclear complexes with the general formulae {[Nd(µH2L1)4(NO3)3]·2H2O}n and [Ln(µ-H2L1)2(NO3)6(H2L1)] (Ln = Gd and Yb). Single-crystal Xray crystallography revealed a ten-coordinate polymeric Nd(III) complex that crystallised in the monoclinic space group P21/c, and isostructural nine-coordinate binuclear Gd(III) and Yb(III) complexes (triclinic system, space group P-1). The lanthanide contraction effect is clear across the series. The flexible nature of HL2 results in the self-assembly of the Nd(III) complex in a 1D polymer chain by acting as the bridge between the metal ions. The Nd-Ophenolate bond distances are 2.403(18), 2.463(17), 2.379(17) and 2.367(19) Å and the average Nd-Onitrate bond length is 2.671 Å. Furthermore, the electronic absorption spectra displays 4f→4f transitions solely for the neodymium(III) compound. The syntheses and characterisation of the lanthanide complexes, [La(HL2)3(NO3)3], [Dy(HL2)2(NO3)3] and [Dy(HL2)2Cl3(H2O)]·2CH2Cl2 with the o-vanillin-derived Schiff base ligand 2-methoxy-6-[(E)-(phenylimino)methyl]phenol (HL2) are reported. The nitro-stabilised La(III) and Dy(III) compounds are ten-coordinate with metabidiminished icosahedron and sphenocorona geometries, respectively. Substitution of the nitrate with chloride ions in the starting metal compounds yielded an eight-coordinate Dy(III) complex that adopts the biaugmented trigonal prism geometry. For all three complexes, HL2 exists as a zwitterion that is bound to the metal centre in a mono- and bidentate fashion via the phenolate and methoxy oxygen atoms. The dysprosium(III) chloride complex is stabilised by both intramolecular N−H···O and intermolecular O−H···C1 hydrogen bonds, while the crystal packing of the Ln(III) nitrate complexes is ensured by mainly intramolecular N−H···O hydrogen bonds. Fluorescence studies displayed characteristic Dy(III) f→f transitions (4F9/2 → 6H15/2), which suggest the ligand HL2 is an effective organic antenna to absorb and transfer energy to the dysprosium ion. A series of mononuclear Nd(III) complexes with the Schiff base derivatives 2-methoxy-6-[(E)(phenylimino)methyl]phenol (HL2), 5-methoxy-2-[(E)-(phenylimino)methyl]phenol (HL3) and 2-methoxy-6-{(E)-[(2-methoxyphenyl)imino]methyl}phenol (HL4) yielded structurally diverse complexes defined by the formulae [Nd(HL2)2(NO3)3], [Nd(HL3)3(NO3)3] and [Nd(HL4)2(NO3)3]·CH3OH. Crystallographic analysis shows HL2 and HL4 coordinate bidentately via the phenolate and methoxy oxygen atoms, while HL3 is bound monodentately through the phenolate oxygen atom. Continuous shape measures depict that the decacoordinate complexes with HL2 and HL4 conform to the sphenocorona and tetradecahedron geometries, respectively, whilst the nona-coordinate Nd(III) complex with HL3 exhibits the muffin geometry. The effect of the ligand substituents and their positions (meta versus para) on the absorption and emission intensities of the complexes is demonstrated. Additionally, the electrochemical behaviour of the o-vanillin-derived Schiff base ligands and their complexes was also investigated, and the results illustrate ligand-based reductions and metal-centred redox potentials that are significantly shifted by the ligand substituents.
- Full Text:
- Date Issued: 2020
Sinxunguphele: a survey of Black attitudes towards South Africa's third State of Emergency in the Eastern Cape
- Authors: De Villiers, Melissa
- Date: 1989
- Subjects: United Democratic Front (South Africa) Alexandria (Cape Province) Africans -- Government relations Freedom of movement Local government -- South Africa -- Eastern Cape Nomzamo Student Guardian Association Nkwinti, Gugile Port Alfred Youth Congress Alexandria Youth Congress (Cape Province) Port Alfred Residents' Civic Association Port Alfred (South Africa) War and emergency legislation -- South Africa
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/2025 , vital:20248 , ISBN 086810177X
- Description: On June 12, 1986, the South African government responded to a strong upsurge in popular resistance with an intensive security crackdown. It is estimated that between 25 000 and 40 000 so- called extra-parliamentary opponents were detained during the first twelve months of South Africa's third state of emergency. These detentions, plus a range of other repressive devices, were part of a determined campaign on the part of the state to reorientate the political process in favour of white domination. There can be little doubt that this third state of emergency, two years old in June 1988, has halted - albeit temporarily - the erosion of the state's authority. Extra-parliamentary opposition has been bruised. Yet Pretoria's purpose is not merely to secure the grudging compliance of a submissive and sullen black community. The government's longer-term aim is to create a climate in which selected "moderate" black groups can be persuaded to endorse a reformed version of the present, apartheid-based, constitution. This report is largely based on the findings of an attitudinal survey of township residents in two Eastern Cape towns which was conducted one year after the third emergency was declared. A considerable volume of information on repression in the Eastern Cape - and, particularly, social conflict emanating from the actions of officials of the state - has been gathered over the past three years by organisations of lawyers, church bodies, local communities, and support and monitoring groups such as the Black Sash. Much of this is in the form of signed statements by eye-witnesses, newspaper reports, and documentation from political trials. However, up to this point no empirical study of any scale of such conditions in the region has been undertaken. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
- Full Text:
- Date Issued: 1989
- Authors: De Villiers, Melissa
- Date: 1989
- Subjects: United Democratic Front (South Africa) Alexandria (Cape Province) Africans -- Government relations Freedom of movement Local government -- South Africa -- Eastern Cape Nomzamo Student Guardian Association Nkwinti, Gugile Port Alfred Youth Congress Alexandria Youth Congress (Cape Province) Port Alfred Residents' Civic Association Port Alfred (South Africa) War and emergency legislation -- South Africa
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/2025 , vital:20248 , ISBN 086810177X
- Description: On June 12, 1986, the South African government responded to a strong upsurge in popular resistance with an intensive security crackdown. It is estimated that between 25 000 and 40 000 so- called extra-parliamentary opponents were detained during the first twelve months of South Africa's third state of emergency. These detentions, plus a range of other repressive devices, were part of a determined campaign on the part of the state to reorientate the political process in favour of white domination. There can be little doubt that this third state of emergency, two years old in June 1988, has halted - albeit temporarily - the erosion of the state's authority. Extra-parliamentary opposition has been bruised. Yet Pretoria's purpose is not merely to secure the grudging compliance of a submissive and sullen black community. The government's longer-term aim is to create a climate in which selected "moderate" black groups can be persuaded to endorse a reformed version of the present, apartheid-based, constitution. This report is largely based on the findings of an attitudinal survey of township residents in two Eastern Cape towns which was conducted one year after the third emergency was declared. A considerable volume of information on repression in the Eastern Cape - and, particularly, social conflict emanating from the actions of officials of the state - has been gathered over the past three years by organisations of lawyers, church bodies, local communities, and support and monitoring groups such as the Black Sash. Much of this is in the form of signed statements by eye-witnesses, newspaper reports, and documentation from political trials. However, up to this point no empirical study of any scale of such conditions in the region has been undertaken. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
- Full Text:
- Date Issued: 1989
The role of non-timber forest products (NTFPs) in the livelihoods of communities in Alfred Nzo District Municipality, Eastern Cape Province
- Authors: Thinyane, Zingisa
- Date: 2019
- Subjects: Non-timber forest products
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14737 , vital:40077
- Description: Non-timber forest products (NTFPs) are renewable natural resources which are harvested by local communities from the surrounding homesteads, fields, grazing lands, woodlands, grasslands and natural habitats. The term NTFP may be used in reference to biological products collected from the domesticated land, semidomesticated land or from the wild. This study examined the use of NTFPs in Alfred Nzo District Municipality, Eastern Cape Province, South Africa, assessing their consumption patterns and contribution to the household well-being. Data on NTFP identity and utilization in the study area were gathered through community focus group discussions and household surveys using semi-structured questionnaires between April 2017 and May 2018. A sample of 124 participants selected via snowball-sampling technique provided detailed accounts on diversity and utilization of NTFPs in the study area. A total of 59 species and eight extractable NTFPs were utilized by the communities in Alfred Nzo District Municipality. The identified eight use categories were herbal medicine (39.0%), edible plants and mushroom (18.0%), firewood (11%), bushmeat (10.0%), forage (9.0%), construction material (6.0%), ceremonial uses (2.0%) and others with miscellaneous uses (5.0%). Popular NTFPs with use values exceeding 0.50 include Agapanthus africanus (L.) Hoffmanns, Bulbine latifolia (L.f.) Spreng., Centella asiatica (L.) Urb, Elephantorrhiza elephantina (Burch.) Skeels, Hypoxis hemerocallidea Fisch., C.A. Mey & Avé-Lall and Leonotis leonurus (L.) R. Br., all used as herbal medicines, Agapanthus africanus (L.) (herbal medicine and ornamental), Datura stromonium L. (herbal medicine, forage and firewood), Dicerothamnus rhinocerotis (L.f) Koekemoer (herbal medicine and fumigant), Aepyceros melampus Lichtenstein, Pavo cristatus L., Struthio camelus L. and Xerus inauris Hemprich & Ehnrenberg as bushmeat. Information on diversity, consumption ii patterns and contribution of NTFPs to livelihood needs of households may enable policy makers and government officers to draft policies required for sustainable management of NTFPs.
- Full Text:
- Date Issued: 2019
- Authors: Thinyane, Zingisa
- Date: 2019
- Subjects: Non-timber forest products
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14737 , vital:40077
- Description: Non-timber forest products (NTFPs) are renewable natural resources which are harvested by local communities from the surrounding homesteads, fields, grazing lands, woodlands, grasslands and natural habitats. The term NTFP may be used in reference to biological products collected from the domesticated land, semidomesticated land or from the wild. This study examined the use of NTFPs in Alfred Nzo District Municipality, Eastern Cape Province, South Africa, assessing their consumption patterns and contribution to the household well-being. Data on NTFP identity and utilization in the study area were gathered through community focus group discussions and household surveys using semi-structured questionnaires between April 2017 and May 2018. A sample of 124 participants selected via snowball-sampling technique provided detailed accounts on diversity and utilization of NTFPs in the study area. A total of 59 species and eight extractable NTFPs were utilized by the communities in Alfred Nzo District Municipality. The identified eight use categories were herbal medicine (39.0%), edible plants and mushroom (18.0%), firewood (11%), bushmeat (10.0%), forage (9.0%), construction material (6.0%), ceremonial uses (2.0%) and others with miscellaneous uses (5.0%). Popular NTFPs with use values exceeding 0.50 include Agapanthus africanus (L.) Hoffmanns, Bulbine latifolia (L.f.) Spreng., Centella asiatica (L.) Urb, Elephantorrhiza elephantina (Burch.) Skeels, Hypoxis hemerocallidea Fisch., C.A. Mey & Avé-Lall and Leonotis leonurus (L.) R. Br., all used as herbal medicines, Agapanthus africanus (L.) (herbal medicine and ornamental), Datura stromonium L. (herbal medicine, forage and firewood), Dicerothamnus rhinocerotis (L.f) Koekemoer (herbal medicine and fumigant), Aepyceros melampus Lichtenstein, Pavo cristatus L., Struthio camelus L. and Xerus inauris Hemprich & Ehnrenberg as bushmeat. Information on diversity, consumption ii patterns and contribution of NTFPs to livelihood needs of households may enable policy makers and government officers to draft policies required for sustainable management of NTFPs.
- Full Text:
- Date Issued: 2019
Interactions between two biological control agents released on Pereskia aculeata Miller (Cactaceae), in South Africa
- Authors: Mnqeta, Zezethu
- Date: 2017
- Subjects: Pereskia aculeata -- Biological control , Cactus -- Biological control -- South Africa , Alien plants -- Biological control -- South Africa , Flea beetles -- South Africa , Coreidae -- South Africa , Insects as biological pest control agents -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7949 , vital:21327
- Description: Pereskia aculeata Miller (Cactaceae) is an alien invasive plant introduced into South Africa from Brazil, which has negative impacts on native biodiversity in South Africa. Phenrica guerini Bechyne (Chrysomelidae) and Catorhintha schaffneri Brailovsky & Garcia (Coreidae) are two biological control agents released against P. aculeata in South Africa. Phenrica guerini was first released against P. aculeata, in 1991, followed by C. schaffneri in 2014. The overall aim of this study was to improve the biological control programme against P. aculeata in order to decrease its density to a level where it does not threaten the native biodiversity of South Africa. The first part of this study evaluated the efficacy of P. guerini on P. aculeata at Port Alfred (Eastern Cape) to better understand the role of P. guerini in the biological control of P. aculeata. An insecticide exclusion experiment was conducted over 100 days. Plots with P. guerini had a mean of 187 (SE ± 62) fewer leaves/m2 than plots without P. guerini. The agent reduced percentage cover in plots with P. guerini, with a mean of 19.42% (SE ± 3.15) lower cover than plots without P. guerini. Although P. guerini had an impact on P. aculeata at Port Alfred previous studies have indicated that a reduction to below 50% cover is required for native biodiversity to recover and the agent only reduced cover to 62% at Port Alfred. Phenrica guerini has therefore not reduced percentage cover sufficiently to completely control the weed. The data collected from Port Alfred was compared to the performance of the agent nationwide. Although P. guerini was found at far more sites than previously recorded, there were very few sites with comparable levels of damage to Port Alfred. This evidence suggests that P. guerini is not sufficiently damaging to reduce P. aculeata to acceptable levels and other biological control agents should be considered.Interactions between two biological control agents can have complex and unexpected impacts for a biological control programme. The second part of this study was to investigate interactions between C. schaffneri and P. guerini under laboratory conditions to test whether the two agents, individually or jointly, enhanced or reduced their impact on P. aculeata. Potted P. aculeata plants were exposed to one of four treatments: control (no agents), P. guerini only, C. schaffneri only and both species in combination. Four stocking densities, ranging from 2 to 12 insects per plant were used. Catorhintha schaffneri alone at high densities was more damaging than all other treatments with a significantly greater reduction in the mean number of leaves, 11.7 (SE ± 1.29), and shoot lengths, 2.17cm (SE ± O. 75). Even at lower density treatments, the combination of the two agents was not significantly more damaging than C. schaffneri alone and C. schaffneri was always more damaging than P. guerini alone. Mortality of P. guerini was significantly higher than C. schaffneri at the highest stocking density when in combination. Phenrica guerini contributes towards the biological control of P. aculeata at some sites in South Africa but not enough to completely control the weed. The antagonistic interaction between P. guerini and C. schaffneri suggests that these agents should not be released together because this would impact negatively on the overall biocontrol programme against P. aculeata. Catorhintha schaffneri should be released at sites were P. guerini is not present and evaluations of the success of this agent in the field should be conducted. Extrapolation of laboratory-based studies into the field is often challenging so mass-rearing of P. guerini should continue until there is convincing proof that C. schaffneri alone is more effective than P. guerini in the field.
- Full Text:
- Date Issued: 2017
- Authors: Mnqeta, Zezethu
- Date: 2017
- Subjects: Pereskia aculeata -- Biological control , Cactus -- Biological control -- South Africa , Alien plants -- Biological control -- South Africa , Flea beetles -- South Africa , Coreidae -- South Africa , Insects as biological pest control agents -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7949 , vital:21327
- Description: Pereskia aculeata Miller (Cactaceae) is an alien invasive plant introduced into South Africa from Brazil, which has negative impacts on native biodiversity in South Africa. Phenrica guerini Bechyne (Chrysomelidae) and Catorhintha schaffneri Brailovsky & Garcia (Coreidae) are two biological control agents released against P. aculeata in South Africa. Phenrica guerini was first released against P. aculeata, in 1991, followed by C. schaffneri in 2014. The overall aim of this study was to improve the biological control programme against P. aculeata in order to decrease its density to a level where it does not threaten the native biodiversity of South Africa. The first part of this study evaluated the efficacy of P. guerini on P. aculeata at Port Alfred (Eastern Cape) to better understand the role of P. guerini in the biological control of P. aculeata. An insecticide exclusion experiment was conducted over 100 days. Plots with P. guerini had a mean of 187 (SE ± 62) fewer leaves/m2 than plots without P. guerini. The agent reduced percentage cover in plots with P. guerini, with a mean of 19.42% (SE ± 3.15) lower cover than plots without P. guerini. Although P. guerini had an impact on P. aculeata at Port Alfred previous studies have indicated that a reduction to below 50% cover is required for native biodiversity to recover and the agent only reduced cover to 62% at Port Alfred. Phenrica guerini has therefore not reduced percentage cover sufficiently to completely control the weed. The data collected from Port Alfred was compared to the performance of the agent nationwide. Although P. guerini was found at far more sites than previously recorded, there were very few sites with comparable levels of damage to Port Alfred. This evidence suggests that P. guerini is not sufficiently damaging to reduce P. aculeata to acceptable levels and other biological control agents should be considered.Interactions between two biological control agents can have complex and unexpected impacts for a biological control programme. The second part of this study was to investigate interactions between C. schaffneri and P. guerini under laboratory conditions to test whether the two agents, individually or jointly, enhanced or reduced their impact on P. aculeata. Potted P. aculeata plants were exposed to one of four treatments: control (no agents), P. guerini only, C. schaffneri only and both species in combination. Four stocking densities, ranging from 2 to 12 insects per plant were used. Catorhintha schaffneri alone at high densities was more damaging than all other treatments with a significantly greater reduction in the mean number of leaves, 11.7 (SE ± 1.29), and shoot lengths, 2.17cm (SE ± O. 75). Even at lower density treatments, the combination of the two agents was not significantly more damaging than C. schaffneri alone and C. schaffneri was always more damaging than P. guerini alone. Mortality of P. guerini was significantly higher than C. schaffneri at the highest stocking density when in combination. Phenrica guerini contributes towards the biological control of P. aculeata at some sites in South Africa but not enough to completely control the weed. The antagonistic interaction between P. guerini and C. schaffneri suggests that these agents should not be released together because this would impact negatively on the overall biocontrol programme against P. aculeata. Catorhintha schaffneri should be released at sites were P. guerini is not present and evaluations of the success of this agent in the field should be conducted. Extrapolation of laboratory-based studies into the field is often challenging so mass-rearing of P. guerini should continue until there is convincing proof that C. schaffneri alone is more effective than P. guerini in the field.
- Full Text:
- Date Issued: 2017
An evaluation of the integrated coordination role of the District Intergovernmental Forum in service delivery : a case of Alfred Nzo District Municipality in the Eastern Cape (2010-2015)
- Authors: Ngxenge, Daphne Nomthandazo
- Date: 2016
- Subjects: Local government -- South Africa -- Eastern Cape Intergovernmental cooperation -- South Africa -- Eastern Cape Intergovernmental fiscal relations -- South Africa
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/9079 , vital:34226
- Description: Intergovernmental relation is a prerequisite for effective performance of the contemporary governments. This research evaluates the roles and functions of intergovernmental forums towards enhancing the improvement of service delivery in the Alfred Nzo District Municipality. The motive of the study was to identify the major inhibitors and the integrated remedial measures that can be suggested. In a bid to accomplish this, the entire research process was guided by the four critical research questions for the study entail the evaluation of: What are the edifiers of the roles and functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM)? What so far are the effects of intergovernmental forums on the performance of Alfred Nzo District Municipality (ANDM)? Which are the inhibitors of the effectiveness of the roles or functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM)? Which hybrid model or recommendation can be suggested for improving the effectiveness of the roles or functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM)? The analysis of the qualitative data that was obtained from 25 sampled participants drawn from Alfred Nzo District Municipality revealed that the edifiers of the roles and functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM) are often linked to the legislations and regulations on intergovernmental relations, information system, and the policy on intergovernmental relations. In response to the question that probed what so far are the effects of intergovernmental forums on the performance of Alfred Nzo District Municipality (ANDM), the participants revealed that the effects of the roles and functions performed by the intergovernmental relations and forums have so far been manifested in the improvement of resource optimisation and service delivery. However, further analysis of the interview findings indicated that as much as Alfred Nzo District municipality has been able to realise some of the positive impacts of intergovernmental relations and forums, there are also still challenges that limit the realisation of the full positive impacts of the implementation of the intergovernmental relation programmes. The thematic content analysis of the interview findings revealed that the major inhibitors of the effectiveness of the roles or functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM) are often linked to the three sets of challenges that include: operational challenges, financial challenges and policy issues. In response to the findings of this research, it is argued that the managers and directors at Alfred Nzo District Municipality must consider using the following strategies if they are to ensure that their established intergovernmental forums influence the successful implementation of joint projects and service delivery of the municipalities within the jurisdiction of intergovernmental relations: Practicalise the Legislative Provisions on Intergovernmental Relations by Developing a Vision and Mission that must be achieved through Intergovernmental Forums, Create a Structure and Framework of Intergovernmental Relation, Allocation of Sufficient Resources for the Implementation of the Joint Projects, and Evaluation of Joint Projects. Future studies can explore the roles of information system towards enhancing the effectiveness of intergovernmental relations.
- Full Text:
- Date Issued: 2016
- Authors: Ngxenge, Daphne Nomthandazo
- Date: 2016
- Subjects: Local government -- South Africa -- Eastern Cape Intergovernmental cooperation -- South Africa -- Eastern Cape Intergovernmental fiscal relations -- South Africa
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/9079 , vital:34226
- Description: Intergovernmental relation is a prerequisite for effective performance of the contemporary governments. This research evaluates the roles and functions of intergovernmental forums towards enhancing the improvement of service delivery in the Alfred Nzo District Municipality. The motive of the study was to identify the major inhibitors and the integrated remedial measures that can be suggested. In a bid to accomplish this, the entire research process was guided by the four critical research questions for the study entail the evaluation of: What are the edifiers of the roles and functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM)? What so far are the effects of intergovernmental forums on the performance of Alfred Nzo District Municipality (ANDM)? Which are the inhibitors of the effectiveness of the roles or functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM)? Which hybrid model or recommendation can be suggested for improving the effectiveness of the roles or functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM)? The analysis of the qualitative data that was obtained from 25 sampled participants drawn from Alfred Nzo District Municipality revealed that the edifiers of the roles and functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM) are often linked to the legislations and regulations on intergovernmental relations, information system, and the policy on intergovernmental relations. In response to the question that probed what so far are the effects of intergovernmental forums on the performance of Alfred Nzo District Municipality (ANDM), the participants revealed that the effects of the roles and functions performed by the intergovernmental relations and forums have so far been manifested in the improvement of resource optimisation and service delivery. However, further analysis of the interview findings indicated that as much as Alfred Nzo District municipality has been able to realise some of the positive impacts of intergovernmental relations and forums, there are also still challenges that limit the realisation of the full positive impacts of the implementation of the intergovernmental relation programmes. The thematic content analysis of the interview findings revealed that the major inhibitors of the effectiveness of the roles or functions of intergovernmental forums in service delivery within the Alfred Nzo District Municipality (ANDM) are often linked to the three sets of challenges that include: operational challenges, financial challenges and policy issues. In response to the findings of this research, it is argued that the managers and directors at Alfred Nzo District Municipality must consider using the following strategies if they are to ensure that their established intergovernmental forums influence the successful implementation of joint projects and service delivery of the municipalities within the jurisdiction of intergovernmental relations: Practicalise the Legislative Provisions on Intergovernmental Relations by Developing a Vision and Mission that must be achieved through Intergovernmental Forums, Create a Structure and Framework of Intergovernmental Relation, Allocation of Sufficient Resources for the Implementation of the Joint Projects, and Evaluation of Joint Projects. Future studies can explore the roles of information system towards enhancing the effectiveness of intergovernmental relations.
- Full Text:
- Date Issued: 2016
Chemical composition of leaf essential oils of Lantana camara varieties in South Africa and their effect on the behavioural preference of Falconia intermedia
- Authors: Ngxande-Koza, Samella W
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4877 , vital:20739
- Description: Lantana camara L. (Verbenaceae) is one the most problematic invaders in South Africa invading forest edges, sand dunes, and shorelines by forming impenetrable thickets. Lantana camara invasions degrade natural biodiversity, reduce the value of land and consequently it has been a target for biological control, over the last 50 years in South Africa. Studies that have reported on chemical profile of Lantana camara have been conducted around the world but not in South Africa. Hence, the first aim of the current study was to identify the chemical baseline of L. camara varieties in the Eastern Cape, South Africa. Recent studies have shown that feeding by one of the agents released against L. camara, Falconia intermedia (Distant) (Hemiptera: Miridae), induces anti-herbivory response through increased leaf toughness and trichome density. A preliminary study conducted also reported the production of volatile chemicals by one variety, Whitney Farm, due to feeding by the mirids. Therefore, the second aim was to determine the induced changes in chemical compounds of L. camara varieties after feeding by F. intermedia. A third aim was to determine the effect these chemical compounds have on the behaviour of F. intermedia. To identify the chemical baseline of L. camara varieties, the essential oils of four L. camara varieties (East London, Port Alfred, Whitney Farm and Heather Glen) were analysed using gas chromatography mass spectrometry (GC-MS) and that resulted to the identification of 163 constitutive and 75 induced chemicals across the varieties tested. Lantana camara varieties showed different chemical classes but were highly dominated by terpenes. A great variation in the number of constitutive chemical compounds was found in all the varieties. There were 56 constitutive chemical compounds in the Whitney Farm variety, 41 in the East London variety, 36 in the Heather Glen variety and 30 in the Port Alfred variety. The Whitney Farm variety had the highest number (22) of unique constitutive chemicals identified when compared with other varieties. This indicates the chemical distinctiveness of the Whitney Farm variety from the other varieties. In the varieties tested, there were common chemical compounds identified in constitutive and induced (discussed below) states of the plants such as caryophyllene, hexane, naphthalene, copaene and a-caryophyllene. Besides naphthalene, the majority of chemical compounds in South African L. camara varieties were similar to compounds that have been identified across the world, suggesting that they are closely related. The expression of naphthalene in these varieties may be due to changes in the chemicals expressed over evolutionary time as predicted by the Novel Weapons Hypothesis. Amongst the varieties, a great variation in chemical compounds and their concentrations was shown in the induced states of the plants. The concentration of constitutive caryophyllene ranged from (3.13 - 15.7) %, to (4.02 - 11.10) % after feeding. The concentration of constitutive hexane ranged from (6.13 - 71.19) %, to (33.3 - 75.8) % after feeding. The concentration of constitutive naphthalene ranged from (0.21 - 4.79) %, to (0.92 - 2.11) % after feeding. The concentration of constitutive copaene ranged from (0.57 - 1.57) %, to (1.20 - 2.72) %. Lastly, the concentration of constitutive a-caryophyllene ranged from (1.18 - 9.03) %, to (0.78 - 5.48) % after feeding. The changes in chemical concentrations in lantana varieties indicated that feeding by the mirid on L. camara varieties causes an induction by either reducing or increasing the chemical concentrations. To determine the effect of the identified compounds on the behaviour of F. intermedia adults, olfactometer bioassays were conducted using a Y-tube technique. A significantly higher proportion of F. intermedia were attracted to undamaged leaves over damaged leaves and purified air. Undamaged leaves attracted 52 % of F. intermedia from the East London variety, 62.5 % from the Port Alfred variety, 56 % from the Whitney Farm variety, 58 % from the Lyndhurst variety and 54.5 % from the Heather Glen variety in dual choice trials versus damaged leaves. Furthermore, a significantly higher proportion of F. intermedia were attracted to damaged leaves over purified air. Damaged leaves attracted 67 % of F. intermedia from the East London variety, 67 % from the Port Alfred variety, 65.9 % from the Whitney Farm variety, 65.3 % from the Heather Glen variety and 64.5 % from the Lyndhurst variety. Olfactometer bioassays were also conducted using purified standard compounds of four chemical compounds identified from essential oils, hexane was used as a positive control as it is reported to be an insect attractant in literature. Hexane was highly attractive to the mirids compared to three standard compounds caryophyllene, caryophyllene oxide and naphthalene at the rate of 80 %, 73 % and 80 %, respectively. The standard compounds tested against F. intermedia are major compounds contained by L. camara varieties and they have proven to have a repellent effect. This may indicate that after feeding by F. intermedia, the major compounds expressed by the plant varieties repel F. intermedia contributing to the invasiveness of this weed. The increased expression of hexane and caryophyllene after feeding may also indicate increased attraction to some insects, opening up the potential for third trophic level interactions in varieties where this is the case. This is the first study on the chemical composition of essential oils of L. camara in South Africa. Therefore, we recommend that where appropriate chemical profile studies of the invasive alien plants should be considered during host specificity testing, and the vital role of chemical compounds on agent-weed interactions must be taken into consideration with other factors before and after the biological control agents are released.
- Full Text:
- Date Issued: 2017
- Authors: Ngxande-Koza, Samella W
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4877 , vital:20739
- Description: Lantana camara L. (Verbenaceae) is one the most problematic invaders in South Africa invading forest edges, sand dunes, and shorelines by forming impenetrable thickets. Lantana camara invasions degrade natural biodiversity, reduce the value of land and consequently it has been a target for biological control, over the last 50 years in South Africa. Studies that have reported on chemical profile of Lantana camara have been conducted around the world but not in South Africa. Hence, the first aim of the current study was to identify the chemical baseline of L. camara varieties in the Eastern Cape, South Africa. Recent studies have shown that feeding by one of the agents released against L. camara, Falconia intermedia (Distant) (Hemiptera: Miridae), induces anti-herbivory response through increased leaf toughness and trichome density. A preliminary study conducted also reported the production of volatile chemicals by one variety, Whitney Farm, due to feeding by the mirids. Therefore, the second aim was to determine the induced changes in chemical compounds of L. camara varieties after feeding by F. intermedia. A third aim was to determine the effect these chemical compounds have on the behaviour of F. intermedia. To identify the chemical baseline of L. camara varieties, the essential oils of four L. camara varieties (East London, Port Alfred, Whitney Farm and Heather Glen) were analysed using gas chromatography mass spectrometry (GC-MS) and that resulted to the identification of 163 constitutive and 75 induced chemicals across the varieties tested. Lantana camara varieties showed different chemical classes but were highly dominated by terpenes. A great variation in the number of constitutive chemical compounds was found in all the varieties. There were 56 constitutive chemical compounds in the Whitney Farm variety, 41 in the East London variety, 36 in the Heather Glen variety and 30 in the Port Alfred variety. The Whitney Farm variety had the highest number (22) of unique constitutive chemicals identified when compared with other varieties. This indicates the chemical distinctiveness of the Whitney Farm variety from the other varieties. In the varieties tested, there were common chemical compounds identified in constitutive and induced (discussed below) states of the plants such as caryophyllene, hexane, naphthalene, copaene and a-caryophyllene. Besides naphthalene, the majority of chemical compounds in South African L. camara varieties were similar to compounds that have been identified across the world, suggesting that they are closely related. The expression of naphthalene in these varieties may be due to changes in the chemicals expressed over evolutionary time as predicted by the Novel Weapons Hypothesis. Amongst the varieties, a great variation in chemical compounds and their concentrations was shown in the induced states of the plants. The concentration of constitutive caryophyllene ranged from (3.13 - 15.7) %, to (4.02 - 11.10) % after feeding. The concentration of constitutive hexane ranged from (6.13 - 71.19) %, to (33.3 - 75.8) % after feeding. The concentration of constitutive naphthalene ranged from (0.21 - 4.79) %, to (0.92 - 2.11) % after feeding. The concentration of constitutive copaene ranged from (0.57 - 1.57) %, to (1.20 - 2.72) %. Lastly, the concentration of constitutive a-caryophyllene ranged from (1.18 - 9.03) %, to (0.78 - 5.48) % after feeding. The changes in chemical concentrations in lantana varieties indicated that feeding by the mirid on L. camara varieties causes an induction by either reducing or increasing the chemical concentrations. To determine the effect of the identified compounds on the behaviour of F. intermedia adults, olfactometer bioassays were conducted using a Y-tube technique. A significantly higher proportion of F. intermedia were attracted to undamaged leaves over damaged leaves and purified air. Undamaged leaves attracted 52 % of F. intermedia from the East London variety, 62.5 % from the Port Alfred variety, 56 % from the Whitney Farm variety, 58 % from the Lyndhurst variety and 54.5 % from the Heather Glen variety in dual choice trials versus damaged leaves. Furthermore, a significantly higher proportion of F. intermedia were attracted to damaged leaves over purified air. Damaged leaves attracted 67 % of F. intermedia from the East London variety, 67 % from the Port Alfred variety, 65.9 % from the Whitney Farm variety, 65.3 % from the Heather Glen variety and 64.5 % from the Lyndhurst variety. Olfactometer bioassays were also conducted using purified standard compounds of four chemical compounds identified from essential oils, hexane was used as a positive control as it is reported to be an insect attractant in literature. Hexane was highly attractive to the mirids compared to three standard compounds caryophyllene, caryophyllene oxide and naphthalene at the rate of 80 %, 73 % and 80 %, respectively. The standard compounds tested against F. intermedia are major compounds contained by L. camara varieties and they have proven to have a repellent effect. This may indicate that after feeding by F. intermedia, the major compounds expressed by the plant varieties repel F. intermedia contributing to the invasiveness of this weed. The increased expression of hexane and caryophyllene after feeding may also indicate increased attraction to some insects, opening up the potential for third trophic level interactions in varieties where this is the case. This is the first study on the chemical composition of essential oils of L. camara in South Africa. Therefore, we recommend that where appropriate chemical profile studies of the invasive alien plants should be considered during host specificity testing, and the vital role of chemical compounds on agent-weed interactions must be taken into consideration with other factors before and after the biological control agents are released.
- Full Text:
- Date Issued: 2017
A social-ecological investigation into urban domestic gardens and avifauna in medium-sized towns of the Eastern Cape, South Africa
- Authors: Tricam, Shayla
- Date: 2020
- Subjects: Urban ecology (Biology) -- South Africa , Biotic communites -- South Africa , Gardens -- South Africa -- Managemenet , Birds – Ecology – South Africa , Gardening to attract birds -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145314 , vital:38427
- Description: Urban domestic gardens are an often overlooked component of urban green infrastructure, despite their potential to contribute to the preservation of urban biodiversity. As opposed to public greenspaces, private gardens are individually owned and managed, thus act as social-ecological systems, where the cumulative actions of urban residents can scale up to influence ecological patterns and processes on a larger scale. The diversity of fauna and flora within urban gardens provide a range of ecosystem goods and services, as well as less tangible benefits in the form of recreation, education and culture. However, little is known about the contribution of urban domestic gardens to urban biodiversity and its potential conservation value in South Africa. This study investigated urban domestic gardens along a socio-economic gradient in two medium-sized towns, Grahamstown and Port Alfred in the Eastern Cape, South Africa. This study found distinct differences among urban resident garden management practices as well as the avifauna which were seen within the gardens across the socio-economic gradient. The Garden Management Intensity index was higher within affluent households compared to other socio-economic levels, with subsequent management scores not differing statistically along the gradient. While there was variation within garden management practices, as well as the number of residents who participated in supplementary bird feeding, little variation was seen in the activities which were enjoyed by the residents, indicating numerous benefits the garden environment provides for all urban residents. The bird community composition along the socio-economic gradient displayed patterns directly reflecting the “luxury effect”, where households with a higher socio-economic status had harbour gardens with greater levels of biodiversity. This study showed that affluent gardens displayed far greater diversity, richness and abundance of urban birds. Multivariate analyses confirmed the patterns by highlighting a distinct bird community in the affluent zone, compared to other two socio-economic zones, which housed a second bird community. Furthermore, the main driver of the bird community composition was dominated by vegetation complexity, most notably tree cover within the gardens. Therefore, this study highlighted that patterns of ecological inequality are highly evident in medium-sized towns in South Africa, where older, affluent suburbs households display greater diversity and abundance of birdlife, compared to subsequent socio-economic zones within the study. Prioritisation with regards to the benefits a garden environment brings to urban residents in terms of a connection to nature, access to urban greenery, and relationship to urban wildlife is vital and should be promoted and planned for across all socio-economic zones.
- Full Text:
- Date Issued: 2020
- Authors: Tricam, Shayla
- Date: 2020
- Subjects: Urban ecology (Biology) -- South Africa , Biotic communites -- South Africa , Gardens -- South Africa -- Managemenet , Birds – Ecology – South Africa , Gardening to attract birds -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145314 , vital:38427
- Description: Urban domestic gardens are an often overlooked component of urban green infrastructure, despite their potential to contribute to the preservation of urban biodiversity. As opposed to public greenspaces, private gardens are individually owned and managed, thus act as social-ecological systems, where the cumulative actions of urban residents can scale up to influence ecological patterns and processes on a larger scale. The diversity of fauna and flora within urban gardens provide a range of ecosystem goods and services, as well as less tangible benefits in the form of recreation, education and culture. However, little is known about the contribution of urban domestic gardens to urban biodiversity and its potential conservation value in South Africa. This study investigated urban domestic gardens along a socio-economic gradient in two medium-sized towns, Grahamstown and Port Alfred in the Eastern Cape, South Africa. This study found distinct differences among urban resident garden management practices as well as the avifauna which were seen within the gardens across the socio-economic gradient. The Garden Management Intensity index was higher within affluent households compared to other socio-economic levels, with subsequent management scores not differing statistically along the gradient. While there was variation within garden management practices, as well as the number of residents who participated in supplementary bird feeding, little variation was seen in the activities which were enjoyed by the residents, indicating numerous benefits the garden environment provides for all urban residents. The bird community composition along the socio-economic gradient displayed patterns directly reflecting the “luxury effect”, where households with a higher socio-economic status had harbour gardens with greater levels of biodiversity. This study showed that affluent gardens displayed far greater diversity, richness and abundance of urban birds. Multivariate analyses confirmed the patterns by highlighting a distinct bird community in the affluent zone, compared to other two socio-economic zones, which housed a second bird community. Furthermore, the main driver of the bird community composition was dominated by vegetation complexity, most notably tree cover within the gardens. Therefore, this study highlighted that patterns of ecological inequality are highly evident in medium-sized towns in South Africa, where older, affluent suburbs households display greater diversity and abundance of birdlife, compared to subsequent socio-economic zones within the study. Prioritisation with regards to the benefits a garden environment brings to urban residents in terms of a connection to nature, access to urban greenery, and relationship to urban wildlife is vital and should be promoted and planned for across all socio-economic zones.
- Full Text:
- Date Issued: 2020
The ballads of Carl Loewe : examined within their cultural, human and aesthetic context
- Authors: Mierowska, Jean Elaine Nora
- Date: 1989
- Subjects: Loewe, Carl, 1796-1869. Songs. Selections Loewe, Carl, 1796-1869. Songs
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2649 , http://hdl.handle.net/10962/d1002314
- Description: This thesis has been written in order to provide, especially for the non-German-reading musician, a fuller picture of Loewe and his ballads than has been available up to now. This picture is developed within the literary background history of the ballad poems, and the literary, mental, and musical climate at the beginning of the Romantic era; further, Loewe's life, as revealed in his many letters, his diaries, and his autobiography, provides the human context from which the ballads emerge as a logical extension of his personality. These earlier parts of the thesis have considerable bearing on the appreciation of Loewe's timely position in musical history, treating as they do with the popularity of the ballad poems, the rapid expansion of the means of musical/emotional expression, and the complete acceptance of that most romantic and versatile of soloinstruments, the piano. Loewe's temperamental affinity with the poetry of the ballads is shown to have affected his choice of subject, and in many cases the ultimate quality of the music is obviously dependent upon the strength or otherwise of his attraction. After observations on Loewe's vocal and piano writing, the thesis treats the ballads primarily with regard to their feeling and emotional content, and investigates the musical means by which this is conveyed. Categories are suggested, and ballads of similar dramatic, pictorial, or emotional type are discussed and compared. Certain formal characteristics are examined, in particular Loewe's use of highly organised motivic work in certain ballads, which foreshadows its later use by Liszt, Wagner and others. Over one hundred of Loewe's 120 ballads are dealt with, some in extensive detail~ and copious musical examples are given. The few comparatively well-known ballads receive due attention, but it was regarded as important to bring to light some of the more neglected or unknown ballads, many of which possess great beauty and originality, amply repaying study and, still more, performance. As a corollary, the approach of the performer is considered, and the Conclusion argues for an informed :esthetic appreciation of Loewe's ballads and their place in teday's vocal repertoire.
- Full Text:
- Date Issued: 1989
- Authors: Mierowska, Jean Elaine Nora
- Date: 1989
- Subjects: Loewe, Carl, 1796-1869. Songs. Selections Loewe, Carl, 1796-1869. Songs
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2649 , http://hdl.handle.net/10962/d1002314
- Description: This thesis has been written in order to provide, especially for the non-German-reading musician, a fuller picture of Loewe and his ballads than has been available up to now. This picture is developed within the literary background history of the ballad poems, and the literary, mental, and musical climate at the beginning of the Romantic era; further, Loewe's life, as revealed in his many letters, his diaries, and his autobiography, provides the human context from which the ballads emerge as a logical extension of his personality. These earlier parts of the thesis have considerable bearing on the appreciation of Loewe's timely position in musical history, treating as they do with the popularity of the ballad poems, the rapid expansion of the means of musical/emotional expression, and the complete acceptance of that most romantic and versatile of soloinstruments, the piano. Loewe's temperamental affinity with the poetry of the ballads is shown to have affected his choice of subject, and in many cases the ultimate quality of the music is obviously dependent upon the strength or otherwise of his attraction. After observations on Loewe's vocal and piano writing, the thesis treats the ballads primarily with regard to their feeling and emotional content, and investigates the musical means by which this is conveyed. Categories are suggested, and ballads of similar dramatic, pictorial, or emotional type are discussed and compared. Certain formal characteristics are examined, in particular Loewe's use of highly organised motivic work in certain ballads, which foreshadows its later use by Liszt, Wagner and others. Over one hundred of Loewe's 120 ballads are dealt with, some in extensive detail~ and copious musical examples are given. The few comparatively well-known ballads receive due attention, but it was regarded as important to bring to light some of the more neglected or unknown ballads, many of which possess great beauty and originality, amply repaying study and, still more, performance. As a corollary, the approach of the performer is considered, and the Conclusion argues for an informed :esthetic appreciation of Loewe's ballads and their place in teday's vocal repertoire.
- Full Text:
- Date Issued: 1989
The potential of Elephantorrhiza elephantina as an anthelmintic of goats in the Eastern Cape province, South Africa
- Authors: Mazhangara, Irene Rumbidza
- Date: 2017
- Subjects: Bioactive compounds -- South Africa -- Eastern Cape Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15068 , vital:40160
- Description: The main objective of the study was to investigate the potential of Elephantorrhiza elephantina in the control of gastro-intestinal worms in goats in the Eastern Cape Province, South Africa. The ethanolic, methanolic and aqueous phytochemical composition of E. elephantina root bark extracts were determined. The phytochemical analysis revealed a high concentration of alkaloids, condensed tannins, flavonoids, phenols and saponins in E. elephantina root extracts. Quantitative phytochemical analysis of alkaloids in water extract was 932.44 ± 1.23 mg. Condensed tannins, phenols and saponins in ethanol extract were 450.52 ± 4.56 mg CE/g, 476.11 ± 0.03 mg GAE/g and 832.85 ± 1.45 mg respectively. Flavonoids was 803.93 ± 0.02 mg QE/g in methanol extract as the highest recordings. In vitro screening of ethanol, methanol and water extracts of E. elephantina for potential anthelminthic activity against adult Paramphistomum cervi worm motility showed time and dose-dependent significant effects after 12 hours of treatment. Ethanolic extracts showed a highly significant (P < 0.05) inhibition of motility (86.67 and 96.67 percent) at concentrations 7.5 and 15 mg/ml, respectively. Methanolic and aqueous extracts exhibited a significant (P < 0.05) motility inhibition (96.67 and 66.67 percent, respectively) at concentration of 15 mg/ml 16 hours post-exposure. In vitro assessment of structural changes to adult gastro-intestinal worms following exposure to E. elephantina extracts was done using scanning electron microscopy (SEM). The SEM observations revealed structural changes in the worms after contact with E. elephantina extracts in comparison with the control worms kept in Phosphate-buffered saline (PBS). The major alterations were around the cuticle, posterior and anterior areas. These changes included longitudinal and transversal folds and thicker cuticula ridges, material aggregates around the posterior and anterior areas. The study showed that ethanol, methanol and water extracts of E. elephantina root contained significant amounts of alkaloids, condensed tannins, flavanoids, phenols and saponins. Validation studies showed that extracts of E. elephantina possess anthelminthic activities. The structural changes found in the worms exposed to extracts of E. elephantina root extracts affected their motility and nutrition, resulting in mortality.
- Full Text:
- Date Issued: 2017
- Authors: Mazhangara, Irene Rumbidza
- Date: 2017
- Subjects: Bioactive compounds -- South Africa -- Eastern Cape Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15068 , vital:40160
- Description: The main objective of the study was to investigate the potential of Elephantorrhiza elephantina in the control of gastro-intestinal worms in goats in the Eastern Cape Province, South Africa. The ethanolic, methanolic and aqueous phytochemical composition of E. elephantina root bark extracts were determined. The phytochemical analysis revealed a high concentration of alkaloids, condensed tannins, flavonoids, phenols and saponins in E. elephantina root extracts. Quantitative phytochemical analysis of alkaloids in water extract was 932.44 ± 1.23 mg. Condensed tannins, phenols and saponins in ethanol extract were 450.52 ± 4.56 mg CE/g, 476.11 ± 0.03 mg GAE/g and 832.85 ± 1.45 mg respectively. Flavonoids was 803.93 ± 0.02 mg QE/g in methanol extract as the highest recordings. In vitro screening of ethanol, methanol and water extracts of E. elephantina for potential anthelminthic activity against adult Paramphistomum cervi worm motility showed time and dose-dependent significant effects after 12 hours of treatment. Ethanolic extracts showed a highly significant (P < 0.05) inhibition of motility (86.67 and 96.67 percent) at concentrations 7.5 and 15 mg/ml, respectively. Methanolic and aqueous extracts exhibited a significant (P < 0.05) motility inhibition (96.67 and 66.67 percent, respectively) at concentration of 15 mg/ml 16 hours post-exposure. In vitro assessment of structural changes to adult gastro-intestinal worms following exposure to E. elephantina extracts was done using scanning electron microscopy (SEM). The SEM observations revealed structural changes in the worms after contact with E. elephantina extracts in comparison with the control worms kept in Phosphate-buffered saline (PBS). The major alterations were around the cuticle, posterior and anterior areas. These changes included longitudinal and transversal folds and thicker cuticula ridges, material aggregates around the posterior and anterior areas. The study showed that ethanol, methanol and water extracts of E. elephantina root contained significant amounts of alkaloids, condensed tannins, flavanoids, phenols and saponins. Validation studies showed that extracts of E. elephantina possess anthelminthic activities. The structural changes found in the worms exposed to extracts of E. elephantina root extracts affected their motility and nutrition, resulting in mortality.
- Full Text:
- Date Issued: 2017
Sir Alfred and Lady Apperly
- Subjects: Workman family -- Photographs , Apperly, Alfred, 1839-1913 -- Photographs Apperly, Maria (Paice), 1846-1931 -- Photographs
- Type: still image
- Identifier: http://hdl.handle.net/10962/50991 , vital:26046 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , PIC/M 7076
- Description: Photograph of Sir Alfred and Lady Apperly.
- Full Text: false
- Subjects: Workman family -- Photographs , Apperly, Alfred, 1839-1913 -- Photographs Apperly, Maria (Paice), 1846-1931 -- Photographs
- Type: still image
- Identifier: http://hdl.handle.net/10962/50991 , vital:26046 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , PIC/M 7076
- Description: Photograph of Sir Alfred and Lady Apperly.
- Full Text: false
Sir Alfred Apperly
- Subjects: Workman family -- Photographs , Apperly, Alfred, 1839-1913 -- Photographs
- Type: still image
- Identifier: http://hdl.handle.net/10962/50995 , vital:26047 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , PIC/M 7077
- Description: Photograph of Sir Alfred Apperly.
- Full Text: false
- Subjects: Workman family -- Photographs , Apperly, Alfred, 1839-1913 -- Photographs
- Type: still image
- Identifier: http://hdl.handle.net/10962/50995 , vital:26047 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , PIC/M 7077
- Description: Photograph of Sir Alfred Apperly.
- Full Text: false
DNA-based identification of forensically significant beetles from Southern Africa
- Authors: Collett, Isabel Judith
- Date: 2015
- Subjects: Carrion insects , Forensic entomology , Cleridae , Dermestidae , Silphidae , Staphylinidae , Scarabaeidae , Histeridae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5923 , http://hdl.handle.net/10962/d1017801
- Description: Necrophilous insects, if correctly identified, can provide useful forensic information. Research in this area has focussed on flies and beetles remain comparatively under-studied, partly because some adult carrion beetles are difficult to identify morphologically, as are their juvenile stages, often requiring specialist expertise in both cases. Molecular taxonomy has been proposed as a solution to these problems. DNA “barcodes" are short fragments of mitochondrial cytochrome oxidase I (COI) DNA that are anticipated to delineate species. This approach is becoming increasingly popular, but has been met with varying enthusiasm from taxonomists. This thesis examines their use in identifying forensically significant beetles.The DNA barcodes of 234 specimens of 25 forensically significant southern African beetle species from seven families (Cleridae, Dermestidae, Silphidae, Staphylinidae, Scarabaeidae, Trogidae and Histeridae) were obtained. Thirty-three initial barcode amplification failures were overcome by using primers other than the standard Folmer pair, undermining the barcode concept’s hope of universal primers that would allow even non-specialists to produce barcodes. Another 150 specimens (64%) entirely failed to yield barcodes, including 18 fresh specimens of three species of Trogidae, implying another lack of universality of the barcoding protocol. The majority of the beetles clustered with confamilials on neighbour-joining and maximum likelihood trees, but 1.3% of the barcodes failed to cluster with their respective families, raising questions concerning the associating power of barcodes. The identification tools of the GenBank and BOLD on-line DNA sequence databases identified 21% of the specimens to the species level, 6% of them correctly. There was evidence of a paralogous sequence in the Cleridae that, while supporting identification now that it has been associated with a morphological identification, would hamper attempts at identification by clustering or phylogenetic analysis.Distance and haplotype network analyses of the barcodes of six widespread species showed that they are not geographically structured. Barcodes are thus unlikely to be indicators of the region of origin of a species and will not determine whether a corpse has been relocated after death. To assess whether a different mitochondrial DNA fragment might address (some of) these problems, a 2.2 kb fragment extending from the 5’ end of the COI gene to the 3’ end of the Cytochrome Oxidase II (COII) gene was analysed for nine species. It was found that, for Dermestidae, Scarabaeidae and Histeridae, higher degrees of diversity occurred downstreamof the barcode region, but the region of highest diversity in the Cleridae was in the barcode region. Thus, finding a more reliable fragment along the COI-COII region for each family may make robust and guaranteed DNA-based identification of these beetles more likely. The possibility of a forensic specimen being incorrectly or not identified based on its barcode alone exists in about 40% of cases, even with the new barcodes reported here. Forensic science sets a very high bar in assessing the performance of its techniques, and it is concluded that barcodes currently have unsettling failure rates as court-worthy evidence.
- Full Text:
- Date Issued: 2015
- Authors: Collett, Isabel Judith
- Date: 2015
- Subjects: Carrion insects , Forensic entomology , Cleridae , Dermestidae , Silphidae , Staphylinidae , Scarabaeidae , Histeridae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5923 , http://hdl.handle.net/10962/d1017801
- Description: Necrophilous insects, if correctly identified, can provide useful forensic information. Research in this area has focussed on flies and beetles remain comparatively under-studied, partly because some adult carrion beetles are difficult to identify morphologically, as are their juvenile stages, often requiring specialist expertise in both cases. Molecular taxonomy has been proposed as a solution to these problems. DNA “barcodes" are short fragments of mitochondrial cytochrome oxidase I (COI) DNA that are anticipated to delineate species. This approach is becoming increasingly popular, but has been met with varying enthusiasm from taxonomists. This thesis examines their use in identifying forensically significant beetles.The DNA barcodes of 234 specimens of 25 forensically significant southern African beetle species from seven families (Cleridae, Dermestidae, Silphidae, Staphylinidae, Scarabaeidae, Trogidae and Histeridae) were obtained. Thirty-three initial barcode amplification failures were overcome by using primers other than the standard Folmer pair, undermining the barcode concept’s hope of universal primers that would allow even non-specialists to produce barcodes. Another 150 specimens (64%) entirely failed to yield barcodes, including 18 fresh specimens of three species of Trogidae, implying another lack of universality of the barcoding protocol. The majority of the beetles clustered with confamilials on neighbour-joining and maximum likelihood trees, but 1.3% of the barcodes failed to cluster with their respective families, raising questions concerning the associating power of barcodes. The identification tools of the GenBank and BOLD on-line DNA sequence databases identified 21% of the specimens to the species level, 6% of them correctly. There was evidence of a paralogous sequence in the Cleridae that, while supporting identification now that it has been associated with a morphological identification, would hamper attempts at identification by clustering or phylogenetic analysis.Distance and haplotype network analyses of the barcodes of six widespread species showed that they are not geographically structured. Barcodes are thus unlikely to be indicators of the region of origin of a species and will not determine whether a corpse has been relocated after death. To assess whether a different mitochondrial DNA fragment might address (some of) these problems, a 2.2 kb fragment extending from the 5’ end of the COI gene to the 3’ end of the Cytochrome Oxidase II (COII) gene was analysed for nine species. It was found that, for Dermestidae, Scarabaeidae and Histeridae, higher degrees of diversity occurred downstreamof the barcode region, but the region of highest diversity in the Cleridae was in the barcode region. Thus, finding a more reliable fragment along the COI-COII region for each family may make robust and guaranteed DNA-based identification of these beetles more likely. The possibility of a forensic specimen being incorrectly or not identified based on its barcode alone exists in about 40% of cases, even with the new barcodes reported here. Forensic science sets a very high bar in assessing the performance of its techniques, and it is concluded that barcodes currently have unsettling failure rates as court-worthy evidence.
- Full Text:
- Date Issued: 2015
Integrated genetic and morphological data support eco‐evolutionary divergence of Angolan and South African populations of Diplodus hottentotus
- Gwilliam, Michael P, Winkler, Alexander C, Potts, Warren M, Santos, Carmen V D, Sauer, Warwick H H, Shaw, Paul W, McKeown, Niall J
- Authors: Gwilliam, Michael P , Winkler, Alexander C , Potts, Warren M , Santos, Carmen V D , Sauer, Warwick H H , Shaw, Paul W , McKeown, Niall J
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124833 , vital:35702 , https://doi.10.1111/jfb.13582
- Description: The genus Diplodus presents multiple cases of taxonomic conjecture. Among these the D. cervinus complex was previously described as comprising three subspecies that are now regarded as separate species: Diplodus cervinus, Diplodus hottentotus and Diplodus omanensis. Diplodus hottentotus exhibits a clear break in its distribution around the Benguela Current system, prompting speculation that Angolan and South African populations flanking this area may be isolated and warrant formal taxonomic distinction. This study reports the first integrated genetic [mitochondrial (mt)DNA and nuclear microsatellite] and morphological (morphometric, meristic and colouration) study to assess patterns of divergence between populations in the two regions. High levels of cytonuclear divergence between the populations support a prolonged period of genetic isolation, with the sharing of only one mtDNA haplotype (12 haplotypes were fully sorted between regions) attributed to retention of ancestral polymorphism. Fish from the two regions were significantly differentiated at a number of morphometric (69·5%) and meristic (46%) characters. In addition, Angolan and South African fish exhibited reciprocally diagnostic colouration patterns that were more similar to Mediterranean and Indian Ocean congeners, respectively. Based on the congruent genetic and phenotypic diversity we suggest that the use of hottentotus, whether for full species or subspecies status, should be restricted to South African D. cervinus to reflect their status as a distinct species-like unit, while the relationship between Angolan and Atlantic–Mediterranean D. cervinus will require further demo-genetic analysis. This study highlights the utility of integrated genetic and morphological approaches to assess taxonomic diversity within the biogeographically dynamic Benguela Current region.
- Full Text:
- Date Issued: 2018
- Authors: Gwilliam, Michael P , Winkler, Alexander C , Potts, Warren M , Santos, Carmen V D , Sauer, Warwick H H , Shaw, Paul W , McKeown, Niall J
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124833 , vital:35702 , https://doi.10.1111/jfb.13582
- Description: The genus Diplodus presents multiple cases of taxonomic conjecture. Among these the D. cervinus complex was previously described as comprising three subspecies that are now regarded as separate species: Diplodus cervinus, Diplodus hottentotus and Diplodus omanensis. Diplodus hottentotus exhibits a clear break in its distribution around the Benguela Current system, prompting speculation that Angolan and South African populations flanking this area may be isolated and warrant formal taxonomic distinction. This study reports the first integrated genetic [mitochondrial (mt)DNA and nuclear microsatellite] and morphological (morphometric, meristic and colouration) study to assess patterns of divergence between populations in the two regions. High levels of cytonuclear divergence between the populations support a prolonged period of genetic isolation, with the sharing of only one mtDNA haplotype (12 haplotypes were fully sorted between regions) attributed to retention of ancestral polymorphism. Fish from the two regions were significantly differentiated at a number of morphometric (69·5%) and meristic (46%) characters. In addition, Angolan and South African fish exhibited reciprocally diagnostic colouration patterns that were more similar to Mediterranean and Indian Ocean congeners, respectively. Based on the congruent genetic and phenotypic diversity we suggest that the use of hottentotus, whether for full species or subspecies status, should be restricted to South African D. cervinus to reflect their status as a distinct species-like unit, while the relationship between Angolan and Atlantic–Mediterranean D. cervinus will require further demo-genetic analysis. This study highlights the utility of integrated genetic and morphological approaches to assess taxonomic diversity within the biogeographically dynamic Benguela Current region.
- Full Text:
- Date Issued: 2018
Contrasting spatial heterogeneity of sessile organisms within mussel (Perna perna L.) beds in relation to topographic variability
- Erlandsson, J, McQuaid, Christopher D, Kostylev, V E
- Authors: Erlandsson, J , McQuaid, Christopher D , Kostylev, V E
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6949 , http://hdl.handle.net/10962/d1011979
- Description: We examined the spatial heterogeneity in three sessile rocky shore organisms, the mussel Perna perna, the barnacle Octomeris angulosa (Sowerby) and the red alga Gelidium pristoides (Turn.) at a range of continuous local scales along horizontal transects within mid- and upper mussel beds of South African shores. We also examined the relationships between variability of organisms and topographic features (rock depressions, slope, aspect), and between mussel, barnacle and algal variability over the same scales. To estimate spatial heterogeneity, we analyzed scaling properties of semivariograms using a fractal approach. Relationships between different variables at the different scales were examined by cross-semivariograms. Spatial dependence of P. perna variability increased with spatial dependence of topographic variability, so that scaling regions of mussel and topographic distributions corresponded well. This relationship often improved with larger local scales (mussel cover increased with depressions, steeper slope and aspect towards waves), while at smaller spatial scales, variability in mussel cover was less well explained by variability in topography. The variability of the barnacle O. angulosa exhibited spatial dependence, even on topographically unstructured shores. In contrast, the distribution of the alga G. pristoides revealed high fractal dimensions, showing spatial independence on topographically unstructured shores. Algae also showed a very strong negative relationship with mussels at most local scales, and a negative relationship with barnacles in upper zones, especially at larger local scales. Barnacles may show clear spatial dependence because of hydrodynamics (at larger local scales) and the need to find a future mate in close proximity (at smaller local scales), while algae may show a strong negative relationship with mussels because of competition for space.
- Full Text:
- Date Issued: 2005
- Authors: Erlandsson, J , McQuaid, Christopher D , Kostylev, V E
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6949 , http://hdl.handle.net/10962/d1011979
- Description: We examined the spatial heterogeneity in three sessile rocky shore organisms, the mussel Perna perna, the barnacle Octomeris angulosa (Sowerby) and the red alga Gelidium pristoides (Turn.) at a range of continuous local scales along horizontal transects within mid- and upper mussel beds of South African shores. We also examined the relationships between variability of organisms and topographic features (rock depressions, slope, aspect), and between mussel, barnacle and algal variability over the same scales. To estimate spatial heterogeneity, we analyzed scaling properties of semivariograms using a fractal approach. Relationships between different variables at the different scales were examined by cross-semivariograms. Spatial dependence of P. perna variability increased with spatial dependence of topographic variability, so that scaling regions of mussel and topographic distributions corresponded well. This relationship often improved with larger local scales (mussel cover increased with depressions, steeper slope and aspect towards waves), while at smaller spatial scales, variability in mussel cover was less well explained by variability in topography. The variability of the barnacle O. angulosa exhibited spatial dependence, even on topographically unstructured shores. In contrast, the distribution of the alga G. pristoides revealed high fractal dimensions, showing spatial independence on topographically unstructured shores. Algae also showed a very strong negative relationship with mussels at most local scales, and a negative relationship with barnacles in upper zones, especially at larger local scales. Barnacles may show clear spatial dependence because of hydrodynamics (at larger local scales) and the need to find a future mate in close proximity (at smaller local scales), while algae may show a strong negative relationship with mussels because of competition for space.
- Full Text:
- Date Issued: 2005