Commensal bacteria belonging to the Staphylococcus Acinetobacter and Stenotrophomonas genera as reservoirs of antibiotic resistance determinants in the environment of Nkonkobe Municipality, Eastern Cape Province , South Africa
- Authors: Adegoke, Anthony Ayodeji
- Date: 2012
- Subjects: Acinetobacter infections Drug resistance in microorganisms Staphylococcal infections Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/6539 , vital:30551
- Description: A study to assess the potentials of some commensal bacteria that belong to Staphylococcus, Acinetobacter and Stenotrophomonas genera as reservoirs of antibiotic resistance determinants in the environment of Nkonkobe Municipality of the Eastern Cape Province, South Africa, was carried out using standard microbiological and molecular techniques. A total of 120 Staphylococcus isolates which consisted of Staphylococcus haemolyticus (30%), Staphylococcus aureus (23.3%) from pig; Staphylococcus capitis (15%) from goat; Staphylococcus heamolyticus (5%) and Staphylococcus xylosus (15%) from cattle and other Staphylococci (11%) from dead chicken and pigs were isolated. About 23.3% of these isolates were coagulase positive and 76.7% were coagulase negative. This difference in prevalence along coagulase production divide was statistically significant (p < 0.05). Eighty-six Acinetobacter species (Acinetobacter baumannii/calcoaceticus and Acinetobacter haemolyticus) were also isolated from Alice and Fort Beaufort towns samples, while 125 Stenotrophomonas maltophilia isolates were from grass root rhizosphere (96%) and soil butternut root rhizosphere (4%). Between 75-100% of the Staphylococccus species were resistant to Penicillin G, tetracycline, sulphamethaxole and nalidixic acid; about 38 % were methicillin resistant, consisting of 12.6% methicillin resistant Staphylococcus aureus (MRSA) from pig and a total of 12% vancomycin resistant were observed. Also, 12% of the isolates were erythromycin resistant while 40.2 % were resistant to the third generation cephalosporin, ceftazidime. The antibiotic resistance genes vanA, VanB, eryA, eryB, eryC were not detected in all the phenotypically resistant Staphylococccus species, but mec A gene and mph genes were detected. In the Acinetobacter species, a wide range of 30-100% resistance to penicillin G, ceftriazone, nitrofurantoin, erythromycin, and augmentin was observed. Polymerase chain reaction (PCR) revealed the presence of Tet(B) and Tet(39) genes in these species, while Tet (A), Tet(M) and Tet(H) were absent. Also, 9.3% of the Acinetobacter species showed phenotypic production of extended spectrum beta lactamases (ESBLs) while 3.5% were positive for the presence of blaCTX-M-1 genes. The Stenotrophomonas maltophilia isolates showed varying resistance to meropenem (8.9%), cefuroxime (95.6 %), ampicillin-sulbactam (53.9%), ceftazidime (10.7%), cefepime (29.3 %), minocycline (2.2%), kanamycin (56.9%), ofloxacin (2.9%), levofloxacin (1.3%), moxifloxacin (2.8%), ciprofloxacin (24.3%), gatifloxacin (1.3%), polymyxin B (2.9 %), cotrimoxazole (26.1%), trimethoprim (98.6%), aztreonam(58%) and Polymyxin B (2.9 %). The isolates exhibited significant susceptibility to the fluoroquinolones (74.3-94.7 %), polymycin (97.1%) and meropenem (88.1%). Only sul3 genes were the only sulphonamide resistance gene detected among the trimethoprim-sulphamethoxazole resistant isolates. The observed multiple antibiotic resistance indeces (MARI) of >2 for Staphylococcus species, Acinetobacter species and Stenotrophomonas maltophilia suggest that they have arisen from high-risk sources where antibiotics are in constant arbitrary use resulting in high selective pressure. The presence of tetracycline resistance genes in Acinetobacter species justifies the observed phenotypic resistance to oxytetracycline and intermediate resistance to minocycline. High phenotypic resistance and the presence of some resistance genes in Staphylococcus species is a possible threat to public health and suggests animals to be important reservoirs of antibiotic resistance determinants in the environment. Indiscriminate use of antibiotics induces this kind of antibiotic resistance and should be discouraged. Personal hygiene is encouraged as it reduces the load of Acinetobacter species contacted from the environment that may be difficult to control. Commensal Stenotrophomonas maltophilia are as important as their clinical counterparts due to their roles in opportunistic infection, antibiotic resistance and their associated genes, especially sul gene. Personal hygiene is hereby advocated especially when in contact with soil, plants and plants’ rhizospheric soil
- Full Text:
- Date Issued: 2012
- Authors: Adegoke, Anthony Ayodeji
- Date: 2012
- Subjects: Acinetobacter infections Drug resistance in microorganisms Staphylococcal infections Bacterial diseases
- Language: English
- Type: Thesis , Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/6539 , vital:30551
- Description: A study to assess the potentials of some commensal bacteria that belong to Staphylococcus, Acinetobacter and Stenotrophomonas genera as reservoirs of antibiotic resistance determinants in the environment of Nkonkobe Municipality of the Eastern Cape Province, South Africa, was carried out using standard microbiological and molecular techniques. A total of 120 Staphylococcus isolates which consisted of Staphylococcus haemolyticus (30%), Staphylococcus aureus (23.3%) from pig; Staphylococcus capitis (15%) from goat; Staphylococcus heamolyticus (5%) and Staphylococcus xylosus (15%) from cattle and other Staphylococci (11%) from dead chicken and pigs were isolated. About 23.3% of these isolates were coagulase positive and 76.7% were coagulase negative. This difference in prevalence along coagulase production divide was statistically significant (p < 0.05). Eighty-six Acinetobacter species (Acinetobacter baumannii/calcoaceticus and Acinetobacter haemolyticus) were also isolated from Alice and Fort Beaufort towns samples, while 125 Stenotrophomonas maltophilia isolates were from grass root rhizosphere (96%) and soil butternut root rhizosphere (4%). Between 75-100% of the Staphylococccus species were resistant to Penicillin G, tetracycline, sulphamethaxole and nalidixic acid; about 38 % were methicillin resistant, consisting of 12.6% methicillin resistant Staphylococcus aureus (MRSA) from pig and a total of 12% vancomycin resistant were observed. Also, 12% of the isolates were erythromycin resistant while 40.2 % were resistant to the third generation cephalosporin, ceftazidime. The antibiotic resistance genes vanA, VanB, eryA, eryB, eryC were not detected in all the phenotypically resistant Staphylococccus species, but mec A gene and mph genes were detected. In the Acinetobacter species, a wide range of 30-100% resistance to penicillin G, ceftriazone, nitrofurantoin, erythromycin, and augmentin was observed. Polymerase chain reaction (PCR) revealed the presence of Tet(B) and Tet(39) genes in these species, while Tet (A), Tet(M) and Tet(H) were absent. Also, 9.3% of the Acinetobacter species showed phenotypic production of extended spectrum beta lactamases (ESBLs) while 3.5% were positive for the presence of blaCTX-M-1 genes. The Stenotrophomonas maltophilia isolates showed varying resistance to meropenem (8.9%), cefuroxime (95.6 %), ampicillin-sulbactam (53.9%), ceftazidime (10.7%), cefepime (29.3 %), minocycline (2.2%), kanamycin (56.9%), ofloxacin (2.9%), levofloxacin (1.3%), moxifloxacin (2.8%), ciprofloxacin (24.3%), gatifloxacin (1.3%), polymyxin B (2.9 %), cotrimoxazole (26.1%), trimethoprim (98.6%), aztreonam(58%) and Polymyxin B (2.9 %). The isolates exhibited significant susceptibility to the fluoroquinolones (74.3-94.7 %), polymycin (97.1%) and meropenem (88.1%). Only sul3 genes were the only sulphonamide resistance gene detected among the trimethoprim-sulphamethoxazole resistant isolates. The observed multiple antibiotic resistance indeces (MARI) of >2 for Staphylococcus species, Acinetobacter species and Stenotrophomonas maltophilia suggest that they have arisen from high-risk sources where antibiotics are in constant arbitrary use resulting in high selective pressure. The presence of tetracycline resistance genes in Acinetobacter species justifies the observed phenotypic resistance to oxytetracycline and intermediate resistance to minocycline. High phenotypic resistance and the presence of some resistance genes in Staphylococcus species is a possible threat to public health and suggests animals to be important reservoirs of antibiotic resistance determinants in the environment. Indiscriminate use of antibiotics induces this kind of antibiotic resistance and should be discouraged. Personal hygiene is encouraged as it reduces the load of Acinetobacter species contacted from the environment that may be difficult to control. Commensal Stenotrophomonas maltophilia are as important as their clinical counterparts due to their roles in opportunistic infection, antibiotic resistance and their associated genes, especially sul gene. Personal hygiene is hereby advocated especially when in contact with soil, plants and plants’ rhizospheric soil
- Full Text:
- Date Issued: 2012
The design, synthesis and antiplasmodial activity of a series of halogenated fosmidomycin analogues and hybrid drugs
- Authors: Afolayan, Anthonia Folake
- Date: 2012
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64370 , vital:28538
- Description: Malaria continues to be a devastating disease and a major cause of death in sub-Saharan Africa. With resistance against most of the available antimalarial drugs, there is a need for ongoing research and development of antimalarial agents. Fosmidomycin and its acetyl analogue FR900098 have been identified as potent inhibitors of Plasmodium falciparum, the causative agent of the most deadly form of malaria. Clinical trials of these agents have revealed poor absorption due to their high hydrophilicity. In the present studies the effect of halogenation of the acyl chain as well as the biological effect of extending the acyl sidechain was explored. This provided the basis on which fosmidomycin hybrids were designed to investigate the feasibility of hybrid extending into NADPH binding pocket. Synthesis of a series of halogenated FR900098 analogues was carried out in three stages. This included i) The introduction of the phosphonate group by reaction with 1,3dibromopropane in an Arbuzov reaction, ii) The introduction of a hydroxamate group by reaction of the propyl phosphonate by means of a nucleophilic substitution reaction with BocNHOBn and iii) The introduction of a halogenated acyl side chain on a protected fosmidomycin backbone. The synthesis of fosmidomycin-hybrids for which chloroquinefosmidomycin hybrids were used as the prototype, involved convergence of the two separately constructed moieties i.e. fosmidomycin and the quinoline moieties in a covalent linkage. The quinoline moiety was easily synthesized from the reaction of 4,7dichloroquinoline with 1,2-diamino ethane. The aminoquinoline so formed resulted in chloroquine-fosmidomycin hybrids 3.8 and 3.9 when reacted with halogenated FR900098 analogues. Antiplasmodial assays were conducted on the chloroquine-fosmidomycin hybrids and the halogenated fosmidomycin derivatives against the chloroquine resistant Gambian FCR-3 strain of P. falciparum. The most potent iodoacetyl fosmidomycin analogues 2.21 gave an IC50 value of 5.54 µM which is eight times more potent than the known antiplasmodial FR900098 which gave an IC50 value of 41.67 µM. All the halogenated FR900098 analogues showed better antiplasmodial activity than their non-halogenated derivatives. This indicated that the presence of halogens in the FR900098 analogues contributes to their biological Chapter 1 Literature review activity. The acetyl and propyl linked hybrids 3.8 and 3.9 showed potent antiplasmodial activity with IC50 values of 0.18 and 0.82 µM respectively. These were by far the most potent hybrids synthesized and provided leads for a new class of promising antimalarial agents. Preliminary E. coli DXR enzyme inhibition assays were carried out on the halogenated fosmidomycin analogues. The results showed good inhibition of the enzyme by the phosphonic acids of the chloroacetyl and chloropropyl analogues 2.1 and 2.2 respectively. Molecular modelling of the compounds on E. coli (PDB code: 2EGH) and P. falciparum (PDB code: 3AUA) DXR showed strong binding of the halogenated fosmidomycin analogues while the hybrids in the absence of docked NADPH showed minimum binding to the enzymes.
- Full Text:
- Date Issued: 2012
- Authors: Afolayan, Anthonia Folake
- Date: 2012
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/64370 , vital:28538
- Description: Malaria continues to be a devastating disease and a major cause of death in sub-Saharan Africa. With resistance against most of the available antimalarial drugs, there is a need for ongoing research and development of antimalarial agents. Fosmidomycin and its acetyl analogue FR900098 have been identified as potent inhibitors of Plasmodium falciparum, the causative agent of the most deadly form of malaria. Clinical trials of these agents have revealed poor absorption due to their high hydrophilicity. In the present studies the effect of halogenation of the acyl chain as well as the biological effect of extending the acyl sidechain was explored. This provided the basis on which fosmidomycin hybrids were designed to investigate the feasibility of hybrid extending into NADPH binding pocket. Synthesis of a series of halogenated FR900098 analogues was carried out in three stages. This included i) The introduction of the phosphonate group by reaction with 1,3dibromopropane in an Arbuzov reaction, ii) The introduction of a hydroxamate group by reaction of the propyl phosphonate by means of a nucleophilic substitution reaction with BocNHOBn and iii) The introduction of a halogenated acyl side chain on a protected fosmidomycin backbone. The synthesis of fosmidomycin-hybrids for which chloroquinefosmidomycin hybrids were used as the prototype, involved convergence of the two separately constructed moieties i.e. fosmidomycin and the quinoline moieties in a covalent linkage. The quinoline moiety was easily synthesized from the reaction of 4,7dichloroquinoline with 1,2-diamino ethane. The aminoquinoline so formed resulted in chloroquine-fosmidomycin hybrids 3.8 and 3.9 when reacted with halogenated FR900098 analogues. Antiplasmodial assays were conducted on the chloroquine-fosmidomycin hybrids and the halogenated fosmidomycin derivatives against the chloroquine resistant Gambian FCR-3 strain of P. falciparum. The most potent iodoacetyl fosmidomycin analogues 2.21 gave an IC50 value of 5.54 µM which is eight times more potent than the known antiplasmodial FR900098 which gave an IC50 value of 41.67 µM. All the halogenated FR900098 analogues showed better antiplasmodial activity than their non-halogenated derivatives. This indicated that the presence of halogens in the FR900098 analogues contributes to their biological Chapter 1 Literature review activity. The acetyl and propyl linked hybrids 3.8 and 3.9 showed potent antiplasmodial activity with IC50 values of 0.18 and 0.82 µM respectively. These were by far the most potent hybrids synthesized and provided leads for a new class of promising antimalarial agents. Preliminary E. coli DXR enzyme inhibition assays were carried out on the halogenated fosmidomycin analogues. The results showed good inhibition of the enzyme by the phosphonic acids of the chloroacetyl and chloropropyl analogues 2.1 and 2.2 respectively. Molecular modelling of the compounds on E. coli (PDB code: 2EGH) and P. falciparum (PDB code: 3AUA) DXR showed strong binding of the halogenated fosmidomycin analogues while the hybrids in the absence of docked NADPH showed minimum binding to the enzymes.
- Full Text:
- Date Issued: 2012
Young veterans, not always social misfits: a sociological discourse of Liberian transmogrification experiences
- Authors: Agbedahin, Komlan
- Date: 2012
- Subjects: Child soldiers -- Liberia Children and war -- Liberia Liberia. Armed Forces -- Demobilization -- Social aspects Liberia -- History -- Civil War, 1989-1996 Liberia -- History -- Civil War, 1999-2003
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3316 , http://hdl.handle.net/10962/d1003104
- Description: This thesis examines the phenomenon of child-soldiering from a different perspective. It seeks to challenge, using a novel approach, earlier studies on the roles of former child-soldiers in post-war societies. It focuses on the subjectivity of young veterans, that is war veterans formerly associated with armed forces and groups as children during the 14-year gruesome civil war which bedevilled Liberia between 1989 and 2003. This civil war claimed roughly 250,000 lives, and saw the active participation of approximately 21,000 child-soldiers. This thesis departs from previous works which mostly painted an apocalyptic picture of young veterans, and explores the nexus between their self-agency, Foucauldian technologies of the self and their transformation in the post-war society. The majority of previous scholarly works which have dominated the field of child-soldiering dwelt on the impact of armed conflict on the child-soldiers, the negative consequences, the causes of child-soldiering, and the rehabilitation and reintegration of the young veterans after their disarmament and demobilization. What this thesis seeks to do however, is to establish that, rather than considering the young veterans simply as social misfits, distraught and dispirited human beings, it should be noted that young veterans through their agency, are capable of ensuring their reintegration into their war-ravaged societies. Sadly, these young former fighters’ self-agency and technologies of the self in defining their civilian trajectories have often been overshadowed by vaunted humanitarian aid and multilayered war-profiteering. This study is underpinned by interpretive constructivism, symbolic interactionism, social identity theory, sociometer theory and expectancy theory, and sheds light on how young veterans’ self-agency, instrumental coalitions, and decision-making processes, synergistically shifted the negative identities foisted on them as a result of their participation in the war.
- Full Text:
- Date Issued: 2012
- Authors: Agbedahin, Komlan
- Date: 2012
- Subjects: Child soldiers -- Liberia Children and war -- Liberia Liberia. Armed Forces -- Demobilization -- Social aspects Liberia -- History -- Civil War, 1989-1996 Liberia -- History -- Civil War, 1999-2003
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3316 , http://hdl.handle.net/10962/d1003104
- Description: This thesis examines the phenomenon of child-soldiering from a different perspective. It seeks to challenge, using a novel approach, earlier studies on the roles of former child-soldiers in post-war societies. It focuses on the subjectivity of young veterans, that is war veterans formerly associated with armed forces and groups as children during the 14-year gruesome civil war which bedevilled Liberia between 1989 and 2003. This civil war claimed roughly 250,000 lives, and saw the active participation of approximately 21,000 child-soldiers. This thesis departs from previous works which mostly painted an apocalyptic picture of young veterans, and explores the nexus between their self-agency, Foucauldian technologies of the self and their transformation in the post-war society. The majority of previous scholarly works which have dominated the field of child-soldiering dwelt on the impact of armed conflict on the child-soldiers, the negative consequences, the causes of child-soldiering, and the rehabilitation and reintegration of the young veterans after their disarmament and demobilization. What this thesis seeks to do however, is to establish that, rather than considering the young veterans simply as social misfits, distraught and dispirited human beings, it should be noted that young veterans through their agency, are capable of ensuring their reintegration into their war-ravaged societies. Sadly, these young former fighters’ self-agency and technologies of the self in defining their civilian trajectories have often been overshadowed by vaunted humanitarian aid and multilayered war-profiteering. This study is underpinned by interpretive constructivism, symbolic interactionism, social identity theory, sociometer theory and expectancy theory, and sheds light on how young veterans’ self-agency, instrumental coalitions, and decision-making processes, synergistically shifted the negative identities foisted on them as a result of their participation in the war.
- Full Text:
- Date Issued: 2012
Quantification of the cross-sectoral impacts of waterweeds and their control in Ghana
- Authors: Akpabey, Felix Jerry
- Date: 2012
- Subjects: Water hyacinth -- Control -- Environmental aspects -- Ghana Alien plants -- Research -- Ghana Introduced organisms Economic development -- Social aspects -- Research -- Ghana
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5748 , http://hdl.handle.net/10962/d1005435
- Description: The Akosombo Dam on the Volta River in Ghana was built in 1963 to provide cheap energy to fuel industry and to accelerate the economic growth of the country. It provides hydroelectric power, enhanced fishing and water transportation upstream, and improved opportunities for irrigated farming, especially in the lower reaches, and their attendant economic multiplier effects. A few years after the construction of this major dam, a rapid expansion of industrialization took place in Ghana. This brought about an exponential increase in demand for more electrical power. This led to the construction of a smaller dam at Akuse, downstream of the Akosomho Dam in 1981 and the formation of a headpond at Kpong. The impoundment of the river at the two sites (Akosombo and Kpong) caused an alteration in the existing ecological and biophysical processes in the river basin, including a slowing of the flow of the river, upstream and downstream. Changes in the natural processes, such as a reduction in the flow of the river and an increase in nutrient status of the water, resulted in an invasion of aquatic weeds, increasing the density of aquatic snails (intermediate hosts of schistosomiasis), silting and closure of the estuary, as well as other more subtle effects. The invasion of the river's main course and the dams by aquatic plants led to a corresponding reduction of navigable water both upstream and downstream. The aim of this thesis was to quantify the impact and control of waterweeds, especially water hyacinth, Eichhornia crassipes (Mart) Solms-Laubach (Pontederiaceae), in Ghana. A floral survey on the Kpong Headpond recorded 49 emergent, 12 free floating and I submerged aquatic plant species, many of which were indigenous, but the exotic or introduced water hyacinth was recorded at most of the sampling sites, and was the most abundant and had the biggest impact on the utilization of the water resource. Mats of water hyacinth served as substrates for other, indigenous species to grow out into the main channel of the headpond, including the intake point of the Kpong head works of the Ghana Water Company Limited (GWCL) and landing sites for boats. These mats resulted in a reduction of the fish (fin and shell) harvest, reducing the annual production to far below demand. Water hyacinth was also shown to have severe health implications. A survey of the Ministry of Health records showed that the prevalence of both urinary and intestinal schistosomiasis had risen significantly over time as the abundance of waterweeds, most notably water hyacinth, increased, and ranged between 70% and 75% but up to 100% in some lakeside communities. Based on the work done by an NGO on board the medical boat ("Onipa Nua "), losses in terms of money due to the effect on health of the aquatic weed infestations on the Volta River in 2006 amounted to US$ 620,000. Economic losses due to invasive alien aquatic weeds were also calculated on the Oti River Arm of Lake Volta. It was estimated that about US$2.3 million per annum would be lost to the Volta Lake Transport Company and individual boat transport operators if this section of the river were 100% covered by aquatic weeds (water hyacinth and Salvinia molesta D.S. Mitchell (Salviniaceae)). It was also estimated that US$327,038 was spent annually in monitoring and managing the weeds in the Oti River. Control interventions for aquatic weeds have been implemented in river systems in Ghana. The biological control agents Neochetina bruchi Hustache (Coleoptera, Curculionidae) and Neochetina eichhorniae Warner (Coleoptera, Curculionidae) have been used on water hyacinth infestations in the Oti River Arm of Lake Volta, the Tano River and the Lagoon complex in the south-western part of the country. Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) has been used to control salvinia, and Neohydronomous affinis Hustache (Coleoptera: Curculionidae) to control water lettuce, Pistia stratiotes Lilmaeus (Araceae) in the Tano River and Lagoon complex. Although these projects have been regarded as successful, they have relied on research from elsewhere in the world and no postrelease quantification has been conducted. In evaluating the impact of the biological control agents Neochetina bruchi and Neochetina eichhorniae weevils on water hyacinth infestations in the Tano River, fresh adult feeding scars were recorded as well as the numbers of adult weevils on each water hyacinth plant sampled at six sites. Despite being released in 1994, weevil numbers and resultant damage to plants in the Tano Lagoon was low in comparison to other regions of the world where these agents have been used. The main reason for this is that this lagoon floods seasonally, washing weevil-infested plants out to sea. Water hyacinth then re-infests the lagoon from seed and the weevil populations are low. To resolve this situation, two courses of action are proposed. The first is to mass rear the weevils along the shore of the lagoon and release them when the first seedlings recruit. The second proposal is that additional agents that have shorter lifecycies and are more mobile than the weevils should be released. To this end, the water hyacinth mirid, Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) was imported from South Africa and released onto the Tano Lagoon in 2009. Retrospective laboratory host specificity trials were conducted on Neachetina eichharniae and Neachetina bruchi weevils 15 years after their release into Ghana to see if any variation in their host ranges had occurred. Considerable damage was inflicted on the E. crassipes leaves by the Neachetina weevils, while little feeding damage was recorded on both Heteranthera callifalia Kunth. (Pontederiaceae) and Eichharnia natans (P.Beauv.) Solms (Pontederiaceae). All the weevils introduced on H callifalia and E. natans died after the first week. This study served to confirm the host specificity and thereby the safety of these agents. Invasive alien aquatic macrophytes have negative impacts on the environment and economy of Ghana. The control of these weeds is essential to socioeconomic development and improved human health standards in riparian communities. Biological control offers a safe and sustainable control option, but requires diligent implementation. However, aquatic weed invasion is more typically a result of the anthropogenically induced eutrophication of water bodies, and this is the main issue that has to be addressed.
- Full Text:
- Date Issued: 2012
- Authors: Akpabey, Felix Jerry
- Date: 2012
- Subjects: Water hyacinth -- Control -- Environmental aspects -- Ghana Alien plants -- Research -- Ghana Introduced organisms Economic development -- Social aspects -- Research -- Ghana
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5748 , http://hdl.handle.net/10962/d1005435
- Description: The Akosombo Dam on the Volta River in Ghana was built in 1963 to provide cheap energy to fuel industry and to accelerate the economic growth of the country. It provides hydroelectric power, enhanced fishing and water transportation upstream, and improved opportunities for irrigated farming, especially in the lower reaches, and their attendant economic multiplier effects. A few years after the construction of this major dam, a rapid expansion of industrialization took place in Ghana. This brought about an exponential increase in demand for more electrical power. This led to the construction of a smaller dam at Akuse, downstream of the Akosomho Dam in 1981 and the formation of a headpond at Kpong. The impoundment of the river at the two sites (Akosombo and Kpong) caused an alteration in the existing ecological and biophysical processes in the river basin, including a slowing of the flow of the river, upstream and downstream. Changes in the natural processes, such as a reduction in the flow of the river and an increase in nutrient status of the water, resulted in an invasion of aquatic weeds, increasing the density of aquatic snails (intermediate hosts of schistosomiasis), silting and closure of the estuary, as well as other more subtle effects. The invasion of the river's main course and the dams by aquatic plants led to a corresponding reduction of navigable water both upstream and downstream. The aim of this thesis was to quantify the impact and control of waterweeds, especially water hyacinth, Eichhornia crassipes (Mart) Solms-Laubach (Pontederiaceae), in Ghana. A floral survey on the Kpong Headpond recorded 49 emergent, 12 free floating and I submerged aquatic plant species, many of which were indigenous, but the exotic or introduced water hyacinth was recorded at most of the sampling sites, and was the most abundant and had the biggest impact on the utilization of the water resource. Mats of water hyacinth served as substrates for other, indigenous species to grow out into the main channel of the headpond, including the intake point of the Kpong head works of the Ghana Water Company Limited (GWCL) and landing sites for boats. These mats resulted in a reduction of the fish (fin and shell) harvest, reducing the annual production to far below demand. Water hyacinth was also shown to have severe health implications. A survey of the Ministry of Health records showed that the prevalence of both urinary and intestinal schistosomiasis had risen significantly over time as the abundance of waterweeds, most notably water hyacinth, increased, and ranged between 70% and 75% but up to 100% in some lakeside communities. Based on the work done by an NGO on board the medical boat ("Onipa Nua "), losses in terms of money due to the effect on health of the aquatic weed infestations on the Volta River in 2006 amounted to US$ 620,000. Economic losses due to invasive alien aquatic weeds were also calculated on the Oti River Arm of Lake Volta. It was estimated that about US$2.3 million per annum would be lost to the Volta Lake Transport Company and individual boat transport operators if this section of the river were 100% covered by aquatic weeds (water hyacinth and Salvinia molesta D.S. Mitchell (Salviniaceae)). It was also estimated that US$327,038 was spent annually in monitoring and managing the weeds in the Oti River. Control interventions for aquatic weeds have been implemented in river systems in Ghana. The biological control agents Neochetina bruchi Hustache (Coleoptera, Curculionidae) and Neochetina eichhorniae Warner (Coleoptera, Curculionidae) have been used on water hyacinth infestations in the Oti River Arm of Lake Volta, the Tano River and the Lagoon complex in the south-western part of the country. Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) has been used to control salvinia, and Neohydronomous affinis Hustache (Coleoptera: Curculionidae) to control water lettuce, Pistia stratiotes Lilmaeus (Araceae) in the Tano River and Lagoon complex. Although these projects have been regarded as successful, they have relied on research from elsewhere in the world and no postrelease quantification has been conducted. In evaluating the impact of the biological control agents Neochetina bruchi and Neochetina eichhorniae weevils on water hyacinth infestations in the Tano River, fresh adult feeding scars were recorded as well as the numbers of adult weevils on each water hyacinth plant sampled at six sites. Despite being released in 1994, weevil numbers and resultant damage to plants in the Tano Lagoon was low in comparison to other regions of the world where these agents have been used. The main reason for this is that this lagoon floods seasonally, washing weevil-infested plants out to sea. Water hyacinth then re-infests the lagoon from seed and the weevil populations are low. To resolve this situation, two courses of action are proposed. The first is to mass rear the weevils along the shore of the lagoon and release them when the first seedlings recruit. The second proposal is that additional agents that have shorter lifecycies and are more mobile than the weevils should be released. To this end, the water hyacinth mirid, Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) was imported from South Africa and released onto the Tano Lagoon in 2009. Retrospective laboratory host specificity trials were conducted on Neachetina eichharniae and Neachetina bruchi weevils 15 years after their release into Ghana to see if any variation in their host ranges had occurred. Considerable damage was inflicted on the E. crassipes leaves by the Neachetina weevils, while little feeding damage was recorded on both Heteranthera callifalia Kunth. (Pontederiaceae) and Eichharnia natans (P.Beauv.) Solms (Pontederiaceae). All the weevils introduced on H callifalia and E. natans died after the first week. This study served to confirm the host specificity and thereby the safety of these agents. Invasive alien aquatic macrophytes have negative impacts on the environment and economy of Ghana. The control of these weeds is essential to socioeconomic development and improved human health standards in riparian communities. Biological control offers a safe and sustainable control option, but requires diligent implementation. However, aquatic weed invasion is more typically a result of the anthropogenically induced eutrophication of water bodies, and this is the main issue that has to be addressed.
- Full Text:
- Date Issued: 2012
The evaluation of an instructional framework using the Van Hiele levels for learning and teaching geometry: a study in five rural senior secondary schools
- Alex, Jogymol Kalariparampil
- Authors: Alex, Jogymol Kalariparampil
- Date: 2012
- Subjects: Teaching and learning -- Geometry -- Education (Secondary)
- Language: English
- Type: Thesis , Doctoral , D Ed
- Identifier: vital:18470 , http://hdl.handle.net/11260/d1011278
- Description: The Constitution (1996) of the Republic of South Africa forms the basis for social transformation in our new society. The Constitution (Act 108 of 1996) and the amendments that followed provided a basis for curriculum transformation and development in South Africa. The Department of Education introduced the present curriculum known as the National Curriculum Statement, which is modern and internationally benchmarked, in grade 10 in 2006. It required the learners to do seven subjects in grades 10 to 12 of which mathematics or mathematical literacy was prescribed as compulsory subjects. To attain social transformation, the South African Government attached a great deal of importance to the learning and teaching of mathematics and sciences in the South African schools. This study was undertaken in an effort to improve the understanding of geometry and, consequently, the performance and achievement of senior secondary school learners in geometry. The study was inspired by the van Hiele theory. The study made use of the different levels of the van Hiele theory for the development of an instructional framework for geometry in senior secondary schools. The research was conducted in a previously disadvantaged area in South Africa. Given the setting of this study and the wider application of it, the use of ‘hands-on’ and practical approach to use manipulatives and worksheets to improve the geometric understanding was tried and tested in this study. The assumption was that such experiences would make the learning of geometry more relevant and enjoyable for learners from limited financial and underprivileged circumstances. A quasi-experimental design was chosen. A total of 359 learners from five purposively selected schools in Mthatha district in the Eastern Cape Province participated in this study. Qualitative data through interviews were gathered. The data were analysed using IBM SPSS Version 19 and Microsoft Excel. Findings indicated that there was a notable improvement in the performance of learners who were taught by the application of the van Hiele theory. The results revealed that most of the learners were not ready for the application of deductive principles of geometry in terms of formal proof in senior secondary school geometry. Based on the results, some recommendations are made to enhance the teaching and learning of geometry in senior secondary schools.
- Full Text:
- Date Issued: 2012
- Authors: Alex, Jogymol Kalariparampil
- Date: 2012
- Subjects: Teaching and learning -- Geometry -- Education (Secondary)
- Language: English
- Type: Thesis , Doctoral , D Ed
- Identifier: vital:18470 , http://hdl.handle.net/11260/d1011278
- Description: The Constitution (1996) of the Republic of South Africa forms the basis for social transformation in our new society. The Constitution (Act 108 of 1996) and the amendments that followed provided a basis for curriculum transformation and development in South Africa. The Department of Education introduced the present curriculum known as the National Curriculum Statement, which is modern and internationally benchmarked, in grade 10 in 2006. It required the learners to do seven subjects in grades 10 to 12 of which mathematics or mathematical literacy was prescribed as compulsory subjects. To attain social transformation, the South African Government attached a great deal of importance to the learning and teaching of mathematics and sciences in the South African schools. This study was undertaken in an effort to improve the understanding of geometry and, consequently, the performance and achievement of senior secondary school learners in geometry. The study was inspired by the van Hiele theory. The study made use of the different levels of the van Hiele theory for the development of an instructional framework for geometry in senior secondary schools. The research was conducted in a previously disadvantaged area in South Africa. Given the setting of this study and the wider application of it, the use of ‘hands-on’ and practical approach to use manipulatives and worksheets to improve the geometric understanding was tried and tested in this study. The assumption was that such experiences would make the learning of geometry more relevant and enjoyable for learners from limited financial and underprivileged circumstances. A quasi-experimental design was chosen. A total of 359 learners from five purposively selected schools in Mthatha district in the Eastern Cape Province participated in this study. Qualitative data through interviews were gathered. The data were analysed using IBM SPSS Version 19 and Microsoft Excel. Findings indicated that there was a notable improvement in the performance of learners who were taught by the application of the van Hiele theory. The results revealed that most of the learners were not ready for the application of deductive principles of geometry in terms of formal proof in senior secondary school geometry. Based on the results, some recommendations are made to enhance the teaching and learning of geometry in senior secondary schools.
- Full Text:
- Date Issued: 2012
Participatory mapping, learning and change in the context of biocultural diversity and resilience
- Authors: Ali, Million Belay
- Date: 2012
- Subjects: Biodiversity conservation -- Research -- Ethiopia Cultural pluralism -- Research -- Ethiopia Ethnopsychology -- Research -- Ethiopia Adult education -- Research -- Ethiopia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1689 , http://hdl.handle.net/10962/d1003572
- Description: This study set out to investigate the learning and change that emerged in and through participatory mapping in the context of biocultural diversity and resilience in rural Ethiopia. It did this through examining the learning and agency emerging from three participatory mapping practices (Participatory 3 Dimensional Modelling, sketch mapping and eco-cultural calendars) using two case study sites, located in the Bale Mountains and the Foata Mountains in Ethiopia, and honing in on in-depth reflective processes in two community contexts located within the broader case study sites, namely Horo Soba, Dinsho wereda in Bale; and Telecho, in Wolmera wereda, in the Foata Mountain complex. This study tried to answer three research questions related to participatory mapping: its role in mobilizing knowledge related to biocultural landscape, its role in learning and change, and its value in building resilience. The study used qualitative case study research methodology underpinned by critical realist philosophy, and used photographic ‘cues’ to structure the reporting on the cases. It used four categories of analysis: biocultural diversity, educational processes, learning and agency, in the first instance to report on the interactions associated with the participatory mapping practices as they emerged in the two case study sites. This was followed by in-depth analysis and interpretation of participatory mapping and biocultural diversity, as well as participatory mapping and learning, with an emphasis on acquisition, meaning making and identity formation processes. The in-depth analysis drew on social and learning theory, and theory of biocultural diversity and social-ecological resilience. The study also included analysis of broader change processes that were related to and emerged from the social interactions in the mapping activities, and the resultant morphogenesis (change), showing that morphogenesis, while broadly temporal, is not linear, and involves ‘little iterative morphogenic cycles’. These insights were then used to interpret how participatory mapping may contribute to resilience building in a context where social-ecological resilience is increasingly required, such as the two case study sites, where socialecological degradation is highly visible and is occurring rapidly. The study’s contribution to new knowledge lies in relation to the role of participatory mapping in facilitating learning, agency and change which, to date, appears to be under-theorised and under-developed in the participatory mapping and environmental education literature. As such, the study findings provide in-depth insight into how participatory mapping methodologies may ‘work in the world’, in contexts such as those presented in the two cases under study. It has tried to demonstrate how participatory mapping has managed to mobilize knowledge related to biocultural diversity, facilitated the acquisition of knowledge and helped members of the community to engage in meaning making activities relevant to their biocultural landscape and renegotiate their identity within the wider community context. It has also shown that dissonance is an important dynamic in the learning process; and that morphogenesis (or change) occurs over time, but also in smaller cycles that interact at different levels; and that participatory mapping cannot, by itself mobilise significant structural change, at least in the short term. It has also shown, however, that learning and the desire for change can emerge from participatory mapping processes, and that this can be utilized to adapt to the changing socio-ecological environments, potentially contributing to longer term resilience of social-ecological systems.
- Full Text:
- Date Issued: 2012
- Authors: Ali, Million Belay
- Date: 2012
- Subjects: Biodiversity conservation -- Research -- Ethiopia Cultural pluralism -- Research -- Ethiopia Ethnopsychology -- Research -- Ethiopia Adult education -- Research -- Ethiopia
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1689 , http://hdl.handle.net/10962/d1003572
- Description: This study set out to investigate the learning and change that emerged in and through participatory mapping in the context of biocultural diversity and resilience in rural Ethiopia. It did this through examining the learning and agency emerging from three participatory mapping practices (Participatory 3 Dimensional Modelling, sketch mapping and eco-cultural calendars) using two case study sites, located in the Bale Mountains and the Foata Mountains in Ethiopia, and honing in on in-depth reflective processes in two community contexts located within the broader case study sites, namely Horo Soba, Dinsho wereda in Bale; and Telecho, in Wolmera wereda, in the Foata Mountain complex. This study tried to answer three research questions related to participatory mapping: its role in mobilizing knowledge related to biocultural landscape, its role in learning and change, and its value in building resilience. The study used qualitative case study research methodology underpinned by critical realist philosophy, and used photographic ‘cues’ to structure the reporting on the cases. It used four categories of analysis: biocultural diversity, educational processes, learning and agency, in the first instance to report on the interactions associated with the participatory mapping practices as they emerged in the two case study sites. This was followed by in-depth analysis and interpretation of participatory mapping and biocultural diversity, as well as participatory mapping and learning, with an emphasis on acquisition, meaning making and identity formation processes. The in-depth analysis drew on social and learning theory, and theory of biocultural diversity and social-ecological resilience. The study also included analysis of broader change processes that were related to and emerged from the social interactions in the mapping activities, and the resultant morphogenesis (change), showing that morphogenesis, while broadly temporal, is not linear, and involves ‘little iterative morphogenic cycles’. These insights were then used to interpret how participatory mapping may contribute to resilience building in a context where social-ecological resilience is increasingly required, such as the two case study sites, where socialecological degradation is highly visible and is occurring rapidly. The study’s contribution to new knowledge lies in relation to the role of participatory mapping in facilitating learning, agency and change which, to date, appears to be under-theorised and under-developed in the participatory mapping and environmental education literature. As such, the study findings provide in-depth insight into how participatory mapping methodologies may ‘work in the world’, in contexts such as those presented in the two cases under study. It has tried to demonstrate how participatory mapping has managed to mobilize knowledge related to biocultural diversity, facilitated the acquisition of knowledge and helped members of the community to engage in meaning making activities relevant to their biocultural landscape and renegotiate their identity within the wider community context. It has also shown that dissonance is an important dynamic in the learning process; and that morphogenesis (or change) occurs over time, but also in smaller cycles that interact at different levels; and that participatory mapping cannot, by itself mobilise significant structural change, at least in the short term. It has also shown, however, that learning and the desire for change can emerge from participatory mapping processes, and that this can be utilized to adapt to the changing socio-ecological environments, potentially contributing to longer term resilience of social-ecological systems.
- Full Text:
- Date Issued: 2012
A comparative study of the language, mathematics and science literacy knowledge and skills of grade 9 learners in secondary schools in Port Elizabeth
- Authors: Arnolds, Keith Victor
- Date: 2012
- Subjects: Educational tests and measurements -- South Africa -- Port Elizabeth , Comparative education , Language and languages -- Study and teaching -- South Africa -- Port Elizabeth , Mathematics -- Study and teaching -- South Africa -- Port Elizabeth , Science -- Study and teaching -- South Africa -- Port Elizabeth , Education, Secondary -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:9566 , http://hdl.handle.net/10948/d1016062
- Description: In South Africa, on-going concerns surrounding the development of learners’ literacy, mathematics and science skills are evident and drive various research studies in this field. International studies and assessments, such as the Trends in International Mathematics and Science Study (TIMSS) and the Progress in International Reading Literacy Study (PIRLS) show major differences in the proficiency levels of learners in South Africa in comparison with their international counter parts. To date, however, the more comprehensive international standardised assessment called the Programme for International Student Assessment (PISA), has not been administered in South Africa. The main aim of this research study was to investigate and scientifically explore the real situation in terms of language, mathematics and science literacy knowledge and skills of Grade 9 learners in South Africa and to draw a comparison between Grade 9 learners from secondary schools in the Port Elizabeth district in South Africa and their international counterparts, using the PISA standardised international assessment. In addition, the aim of the study was to determine the actual language, mathematics and science literacy skills and knowledge acquired by participants in this study. Quantitative data collection was done by administering a modified version of the Program for International Student Assessment (PISA) to learners from eight schools in Port Elizabeth, supplemented with questionnaires completed by participating learners and school principals. Findings revealed that the South African learners sampled, ranked in the bottom percentile of participating countries in reading, mathematics and science. The study also exposed the glaring inequalities still prevalent in South African education today, 17 years into democracy. The implications point to a serious investigation into the societal and political factors responsible for the discrepancies in the South African educational system at present.
- Full Text:
- Date Issued: 2012
- Authors: Arnolds, Keith Victor
- Date: 2012
- Subjects: Educational tests and measurements -- South Africa -- Port Elizabeth , Comparative education , Language and languages -- Study and teaching -- South Africa -- Port Elizabeth , Mathematics -- Study and teaching -- South Africa -- Port Elizabeth , Science -- Study and teaching -- South Africa -- Port Elizabeth , Education, Secondary -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:9566 , http://hdl.handle.net/10948/d1016062
- Description: In South Africa, on-going concerns surrounding the development of learners’ literacy, mathematics and science skills are evident and drive various research studies in this field. International studies and assessments, such as the Trends in International Mathematics and Science Study (TIMSS) and the Progress in International Reading Literacy Study (PIRLS) show major differences in the proficiency levels of learners in South Africa in comparison with their international counter parts. To date, however, the more comprehensive international standardised assessment called the Programme for International Student Assessment (PISA), has not been administered in South Africa. The main aim of this research study was to investigate and scientifically explore the real situation in terms of language, mathematics and science literacy knowledge and skills of Grade 9 learners in South Africa and to draw a comparison between Grade 9 learners from secondary schools in the Port Elizabeth district in South Africa and their international counterparts, using the PISA standardised international assessment. In addition, the aim of the study was to determine the actual language, mathematics and science literacy skills and knowledge acquired by participants in this study. Quantitative data collection was done by administering a modified version of the Program for International Student Assessment (PISA) to learners from eight schools in Port Elizabeth, supplemented with questionnaires completed by participating learners and school principals. Findings revealed that the South African learners sampled, ranked in the bottom percentile of participating countries in reading, mathematics and science. The study also exposed the glaring inequalities still prevalent in South African education today, 17 years into democracy. The implications point to a serious investigation into the societal and political factors responsible for the discrepancies in the South African educational system at present.
- Full Text:
- Date Issued: 2012
Effective and efficient performance management in local government, with reference to the Cacadu District Municipality
- Authors: Asmah-Andoh, Kwame
- Date: 2012
- Subjects: Performance -- Management , Performance standards -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8161 , http://hdl.handle.net/10948/1633 , Performance -- Management , Performance standards -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa
- Description: This study examined the existing levels of effectiveness and efficiency in local government with the application of performance management systems in the provision of municipal services. The provision of district-wide water services in Cacadu District Municipality in the Province of the Eastern Cape, South Africa is used for particular reference. Local government reforms after 1994 led to the creation of the district municipality (which groups together a number of local municipalities) to drive district-wide services provision, the introduction of systematic services provision standards and performance management as part of management reforms in municipalities. The problem for the research deals with how the Cacadu District Council and the councils of the local municipalities within the district are collaborating in using performance management systems, what effects this could have on programmes and services provision and how communication of performance information would improve service provision. Conceptual and practical difficulties encountered in effective and efficient utilisation and some obstacles that contribute to impeding progress in the use of performance management systems in municipalities were analysed. The qualitative research included a review of documents from the public administration and management literature; discourse analysis of interviews with municipal councilors and appointed officials, community members and provincial managers. The document review included a review of municipal documents that incorporated performance management or described development and use of performance management systems. It also included the legal frameworks and statutory requirements for municipal government and administration. All the responding municipal councils within the Cacadu District Municipality reported using performance management over the past five years yet little empirical evidence explains usage for district-wide programmes and services provision. Research shows that a comprehensive performance management approach to programmes and services has a more effective and efficient impact on service improvement than utilisation of personnnel appraisal (Ammons and Rivenbark, 2005). Despite the expected benefits, personnel performance appraisal is often flawed and the need exists in the district municipal model to develop and utilise performance management systems that validly assess the work performance of personnel (Hindo, 2010). Performance management system utilisation in decision making management is more related to the long-term benefits of effectiveness and efficiency than personnel appraisal for performance rewards and reporting. To overcome and address a situation of managing performance without a performance management system the study proposes a programme performance measurement and management system which incorporates information on management inputs, programme-specific data and citizens' feedback for outcomes and impact of the service. The suggested design for district-wide and specific municipal services provision elicit and provide relevant and appropriate performance information for management, decision-making and accountability to community. The effectiveness of the proposed system is to provide information for decision-making, long-term planning, strategic management and accountability reporting. The proposal is built on the exisiting method and thus efficient in the utilisation of resources. This has implications both for the theory of Public Administration and Management and the practical application of performamce management in public institutions. The study explicity provides a Public Administration perspective on management in a multi-municipal district context with different authorities. The study contributes to the theory of administrative policy and management context of the municipality with special attention to functions for which different authorities are responsible and the role of a performance system for better insught into managing overlapping authority, gaps and duplications. A central purpose of public management research is to theorise and influence practice. The practical utilisation of the proposed method is intended to assist managers and politicians with better understanding of a sustainable performance management system.
- Full Text:
- Date Issued: 2012
- Authors: Asmah-Andoh, Kwame
- Date: 2012
- Subjects: Performance -- Management , Performance standards -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8161 , http://hdl.handle.net/10948/1633 , Performance -- Management , Performance standards -- South Africa -- Eastern Cape , Municipal government -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa
- Description: This study examined the existing levels of effectiveness and efficiency in local government with the application of performance management systems in the provision of municipal services. The provision of district-wide water services in Cacadu District Municipality in the Province of the Eastern Cape, South Africa is used for particular reference. Local government reforms after 1994 led to the creation of the district municipality (which groups together a number of local municipalities) to drive district-wide services provision, the introduction of systematic services provision standards and performance management as part of management reforms in municipalities. The problem for the research deals with how the Cacadu District Council and the councils of the local municipalities within the district are collaborating in using performance management systems, what effects this could have on programmes and services provision and how communication of performance information would improve service provision. Conceptual and practical difficulties encountered in effective and efficient utilisation and some obstacles that contribute to impeding progress in the use of performance management systems in municipalities were analysed. The qualitative research included a review of documents from the public administration and management literature; discourse analysis of interviews with municipal councilors and appointed officials, community members and provincial managers. The document review included a review of municipal documents that incorporated performance management or described development and use of performance management systems. It also included the legal frameworks and statutory requirements for municipal government and administration. All the responding municipal councils within the Cacadu District Municipality reported using performance management over the past five years yet little empirical evidence explains usage for district-wide programmes and services provision. Research shows that a comprehensive performance management approach to programmes and services has a more effective and efficient impact on service improvement than utilisation of personnnel appraisal (Ammons and Rivenbark, 2005). Despite the expected benefits, personnel performance appraisal is often flawed and the need exists in the district municipal model to develop and utilise performance management systems that validly assess the work performance of personnel (Hindo, 2010). Performance management system utilisation in decision making management is more related to the long-term benefits of effectiveness and efficiency than personnel appraisal for performance rewards and reporting. To overcome and address a situation of managing performance without a performance management system the study proposes a programme performance measurement and management system which incorporates information on management inputs, programme-specific data and citizens' feedback for outcomes and impact of the service. The suggested design for district-wide and specific municipal services provision elicit and provide relevant and appropriate performance information for management, decision-making and accountability to community. The effectiveness of the proposed system is to provide information for decision-making, long-term planning, strategic management and accountability reporting. The proposal is built on the exisiting method and thus efficient in the utilisation of resources. This has implications both for the theory of Public Administration and Management and the practical application of performamce management in public institutions. The study explicity provides a Public Administration perspective on management in a multi-municipal district context with different authorities. The study contributes to the theory of administrative policy and management context of the municipality with special attention to functions for which different authorities are responsible and the role of a performance system for better insught into managing overlapping authority, gaps and duplications. A central purpose of public management research is to theorise and influence practice. The practical utilisation of the proposed method is intended to assist managers and politicians with better understanding of a sustainable performance management system.
- Full Text:
- Date Issued: 2012
The allelopathic potential of Arctotis Arctotoides (L.f.) O. Hoffm on some vegetables
- Authors: Badmus, Abimbola Adesile
- Date: 2012
- Subjects: Allelopathy , Allelopathic agents , Vegetables -- Microbiology , Enzyme inhibitors
- Language: English
- Type: Thesis , Doctoral , PhD (Botany)
- Identifier: vital:11306 , http://hdl.handle.net/10353/454 , Allelopathy , Allelopathic agents , Vegetables -- Microbiology , Enzyme inhibitors
- Description: Laboratory and greenhouse experiments were conducted to evaluate the allelopathic effects of the extracts and residue Arctotis arctotoides (L.f.) O. Hoffm on selected vegetable crops. The study aimed to address the following specific objectives to (i) examine the ultra structures of the leaf of A. arctotoides using the Scanning Electron Microscope (SEM), (ii) carry out comprehensive qualitative and quantitative phytochemical analysis of the root and shoot materials of the plant, (iii) investigate the allelopathic activities of the root and shoot aqueous extracts of A. arctotoides at concentrations of 10, 8, 6, 4 and 2 mg/ml on germination, radicle and plumule growth of cabbage, carrot, tomato and spinach, (iv) evaluate the inhibitory effects of the dried shoot residue of the plant at 10, 20 and 40 g kg-3 of soil (treatments B, C and D) and the control (treatment A) on the morphology, growth and chlorophyll pigment content of tomato and cabbage transplants at 1, 2, 3 and 4 weeks after transplanting and (v) assess the effects of the dried shoot residue of A. arctotoides on the yield, nutrient uptake by the leaves of tomato and cabbage at 4 and 12 weeks after transplanting. Finally, to analyze the residual mineral content of the soils with tomato and cabbage transplants at 12 weeks after transplanting. The the SEM revealed that anisocytic stomata and glandular trichomes (GTs) were numerous on the abaxial than the adaxial surfaces of A. arctotoides. The non glandular trichomes (NGTs) were also present on both surfaces but lesser on the abaxial. Morphologically, the GTs were peltate, uniseriate and globular head while the NGTs were cylindrical and filamentous with variable number of cells at the basal portion. The energy dispersive X-ray spectroscopy of some crystals showed that Na+ Mg2+ and Ca2+ were the major constituents of the crystal deposit found around the GTs and stomata. The results of the phytochemical composition of the root and shoot extracts of A. arctotoides confirmed the occurrence of alkaloids, flavonoids, phenolics, saponnins, tannins and triterpenes as the common constituents. In addition, cardiac glycosides and steroids were also detected in the shoot of the A. arctotoides. Quantitative estimation of the chemical constituents of the crude extracts further revealed that the alkaloid content in the root higher (0.97 percent) than the shoot (0.64 percent). The quantity of flavonoids detected in the shoot (1.02 percent) was more than that observed in the root (0.35 percent). Others (phenolics and tannins) were marginal in the two plant parts. The results of the inhibitory effects of the root and shoot aqueous extract at the varying concentrations showed that root extract at 10 mg/ml considerably reduced the germination of cabbage, carrot, tomato and spinach seeds by 84.0, 83.2, 72.8 and 37.4 percent respectively. Incubation of the shoot extract at the same concentration resulted in 100 percent inhibition of cabbage and carrot seed germination whereas those of tomato and spinach were suppressed by 91.5 and 61.2 percent respectively. The two extracts at the varying concentrations also had a significant reduction on the radicle and plumule growth of the four vegetables. Addition of the shoot residue to the soil showed massive chlorosis, necrotic lesions and wilting of tomato and cabbage leaves under treatments C and D at 2 weeks after transplanting. The number of leaves, leaf area, dry shoot and root weight of the two vegetables grown in the amended soils were also drastically reduced. The inhibition percentages due to the addition of the three concentrations of A. arctotoides dried shoot residue on the dry shoot weight at 4 weeks after transplanting were 38.6, 45.5 and 70.3. for tomato and 57.5, 73.3 and 87.5 percent for cabbage. Similarly, the declines in the dry root weight of 61.3, 82.9.4 and 83.4 percent for tomato as well as 53.1, 54.7 and 67.2 percent for cabbages were recorded for the two vegetables under treatment B, C and D during the period. The results further showed that the dry fruit yield and shoot weight of tomato under the treatments B, C and D decreased with increase in shoot residue concentrations of A. arctotoides. Relative to treatment A, no significant differences were recorded in the dry head weight of cabbage under the residue treated groups. The reductions in the fruit yield and fresh head weight caused by treatments C and D were 37.2 and 84.8 percent for tomato and 30.9 and 72.4 percent for cabbage. The findings on the mineral contents in the leaves of the two vegetables revealed significant differences in the uptake of N, Mg, Na, Cu and Fe by tomato leaves. The concentrations of N, K, Na and Zn in cabbage leaves also differed. However, the P content was relatively constant in the leaves of the two vegetables at 4 and 12 weeks after transplanting. At 12 weeks after transplanting, the Fe content in soils with tomato and cabbage treatments C and D was greatly enhanced in comparison with the other nutrients. The residual N, P and Zn detected in soils planted to cabbage were similarly equal among all the groups including the control. Thus, under the greenhouse experiment, Arctotis arctotoides (L.f) O. Hoffm has been shown to contain some phytotoxic chemical compounds in its root and shoot materials. The compounds either singly or collectively have demonstrated some inhibitory potentials on the germination, growth and yields of cabbage, carrot, tomato and spinach evaluated in this study.
- Full Text:
- Date Issued: 2012
- Authors: Badmus, Abimbola Adesile
- Date: 2012
- Subjects: Allelopathy , Allelopathic agents , Vegetables -- Microbiology , Enzyme inhibitors
- Language: English
- Type: Thesis , Doctoral , PhD (Botany)
- Identifier: vital:11306 , http://hdl.handle.net/10353/454 , Allelopathy , Allelopathic agents , Vegetables -- Microbiology , Enzyme inhibitors
- Description: Laboratory and greenhouse experiments were conducted to evaluate the allelopathic effects of the extracts and residue Arctotis arctotoides (L.f.) O. Hoffm on selected vegetable crops. The study aimed to address the following specific objectives to (i) examine the ultra structures of the leaf of A. arctotoides using the Scanning Electron Microscope (SEM), (ii) carry out comprehensive qualitative and quantitative phytochemical analysis of the root and shoot materials of the plant, (iii) investigate the allelopathic activities of the root and shoot aqueous extracts of A. arctotoides at concentrations of 10, 8, 6, 4 and 2 mg/ml on germination, radicle and plumule growth of cabbage, carrot, tomato and spinach, (iv) evaluate the inhibitory effects of the dried shoot residue of the plant at 10, 20 and 40 g kg-3 of soil (treatments B, C and D) and the control (treatment A) on the morphology, growth and chlorophyll pigment content of tomato and cabbage transplants at 1, 2, 3 and 4 weeks after transplanting and (v) assess the effects of the dried shoot residue of A. arctotoides on the yield, nutrient uptake by the leaves of tomato and cabbage at 4 and 12 weeks after transplanting. Finally, to analyze the residual mineral content of the soils with tomato and cabbage transplants at 12 weeks after transplanting. The the SEM revealed that anisocytic stomata and glandular trichomes (GTs) were numerous on the abaxial than the adaxial surfaces of A. arctotoides. The non glandular trichomes (NGTs) were also present on both surfaces but lesser on the abaxial. Morphologically, the GTs were peltate, uniseriate and globular head while the NGTs were cylindrical and filamentous with variable number of cells at the basal portion. The energy dispersive X-ray spectroscopy of some crystals showed that Na+ Mg2+ and Ca2+ were the major constituents of the crystal deposit found around the GTs and stomata. The results of the phytochemical composition of the root and shoot extracts of A. arctotoides confirmed the occurrence of alkaloids, flavonoids, phenolics, saponnins, tannins and triterpenes as the common constituents. In addition, cardiac glycosides and steroids were also detected in the shoot of the A. arctotoides. Quantitative estimation of the chemical constituents of the crude extracts further revealed that the alkaloid content in the root higher (0.97 percent) than the shoot (0.64 percent). The quantity of flavonoids detected in the shoot (1.02 percent) was more than that observed in the root (0.35 percent). Others (phenolics and tannins) were marginal in the two plant parts. The results of the inhibitory effects of the root and shoot aqueous extract at the varying concentrations showed that root extract at 10 mg/ml considerably reduced the germination of cabbage, carrot, tomato and spinach seeds by 84.0, 83.2, 72.8 and 37.4 percent respectively. Incubation of the shoot extract at the same concentration resulted in 100 percent inhibition of cabbage and carrot seed germination whereas those of tomato and spinach were suppressed by 91.5 and 61.2 percent respectively. The two extracts at the varying concentrations also had a significant reduction on the radicle and plumule growth of the four vegetables. Addition of the shoot residue to the soil showed massive chlorosis, necrotic lesions and wilting of tomato and cabbage leaves under treatments C and D at 2 weeks after transplanting. The number of leaves, leaf area, dry shoot and root weight of the two vegetables grown in the amended soils were also drastically reduced. The inhibition percentages due to the addition of the three concentrations of A. arctotoides dried shoot residue on the dry shoot weight at 4 weeks after transplanting were 38.6, 45.5 and 70.3. for tomato and 57.5, 73.3 and 87.5 percent for cabbage. Similarly, the declines in the dry root weight of 61.3, 82.9.4 and 83.4 percent for tomato as well as 53.1, 54.7 and 67.2 percent for cabbages were recorded for the two vegetables under treatment B, C and D during the period. The results further showed that the dry fruit yield and shoot weight of tomato under the treatments B, C and D decreased with increase in shoot residue concentrations of A. arctotoides. Relative to treatment A, no significant differences were recorded in the dry head weight of cabbage under the residue treated groups. The reductions in the fruit yield and fresh head weight caused by treatments C and D were 37.2 and 84.8 percent for tomato and 30.9 and 72.4 percent for cabbage. The findings on the mineral contents in the leaves of the two vegetables revealed significant differences in the uptake of N, Mg, Na, Cu and Fe by tomato leaves. The concentrations of N, K, Na and Zn in cabbage leaves also differed. However, the P content was relatively constant in the leaves of the two vegetables at 4 and 12 weeks after transplanting. At 12 weeks after transplanting, the Fe content in soils with tomato and cabbage treatments C and D was greatly enhanced in comparison with the other nutrients. The residual N, P and Zn detected in soils planted to cabbage were similarly equal among all the groups including the control. Thus, under the greenhouse experiment, Arctotis arctotoides (L.f) O. Hoffm has been shown to contain some phytotoxic chemical compounds in its root and shoot materials. The compounds either singly or collectively have demonstrated some inhibitory potentials on the germination, growth and yields of cabbage, carrot, tomato and spinach evaluated in this study.
- Full Text:
- Date Issued: 2012
Development of molecularly imprinted polymer based solid phase extraction sorbents for the selective cleanup of food and pharmaceutical residue samples
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012
Movement patterns, stock delineation and conservation of an overexploited fishery species, Lithognathus Lithognathus (Pisces: Sparidae)
- Authors: Bennett, Rhett Hamilton
- Date: 2012
- Subjects: Reef fishes -- Behavior , Endangered species -- South Africa , Fish stock assessment -- South Africa , Fishery management -- South Africa , Fish communities -- South Africa , Sparidae , Lithognathus , Lithognathus -- Growth
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5374 , http://hdl.handle.net/10962/d1015709
- Description: White steenbras Lithognathus lithognathus (Pisces: Sparidae) has been a major target species of numerous fisheries in South Africa, since the late 19th century. Historically, it contributed substantially to annual catches in commercial net fisheries, and became dominant in recreational shore catches in the latter half of the 20th century. However, overexploitation in both sectors resulted in severe declines in abundance. The ultimate collapse of the stock by the end of the last century, and the failure of traditional management measures to protect the species indicate that a new management approach for this species is necessary. The species was identified as a priority for research, management and conservation in a National Linefish Status Report. Despite knowledge on aspects of its biology and life history, little is known about juvenile habitat use patterns, home range dynamics and movement behaviour in estuaries. Similarly, the movement and migration of larger juveniles and adults in the marine environment are poorly understood. Furthermore, there is a complete lack of information on its genetic stock structure. Such information is essential for effective management of a fishery species. This thesis aimed to address the gaps in the understanding of white steenbras movement patterns and genetic stock structure, and provide an assessment of its current conservation status. The study adopted a multidisciplinary approach, incorporating a range of methods and drawing on available information, including published literature, unpublished reports and data from long-term monitoring programmes. Acoustic telemetry, conducted in a range of estuaries, showed high site fidelity, restricted area use, small home ranges relative to the size of the estuary, and a high level of residency within estuaries at the early juvenile life stage. Behaviour within estuaries was dominated by station-keeping, superimposed by a strong diel behaviour, presumably based on feeding and/or predator avoidance, with individuals entering the shallow littoral zone at night to feed, and seeking refuge in the deeper channel areas during the daytime. Conventional dart tagging and recapture data from four ongoing, long-term coastal fish tagging projects, spread throughout the distribution of this species, indicated high levels of residency in the surf zone at the late juvenile and sub-adult life stages. Consequently, juvenile and sub-adult white steenbras are vulnerable to localised depletion, although they can be effectively protected by suitably positioned estuarine protected areas (EPAs) and marine protected areas (MPAs), respectively. It has been hypothesized that adult white steenbras undertake large-scale coastal migrations between summer aggregation areas and winter spawning grounds. The scale of observed coastal movements was correlated with fish size (and age), with larger fish undertaking considerably longer-distance coastal movements than smaller individuals, supporting this hypothesis. Given the migratory behaviour of adults, and indications that limited spawning habitat exists, MPAs designed to protect white steenbras during the adult life stage should encompass all known spawning aggregation sites. The fishery is plagued by problems such as low compliance and low enforcement capacity, and alternative management measures, such as seasonal closure, need to be evaluated. Despite considerable conventional dart tagging effort around the coastline (5 782 fish tagged) with 292 recaptures there remains a lack of empirical evidence of fish migrating long distances (> 600 km) between aggregation and spawning areas. This uncertainty in the level of connectivity among coastal regions was addressed using mitochondrial DNA sequencing and genotyping of microsatellite repeat loci in the nuclear genome, which showed no evidence of major geographic barriers to gene flow in this species. Samples collected throughout the white steenbras core distribution showed high genetic diversity, low genetic differentiation and no evidence of isolation by distance or localised spawning. Although historically dominant in several fisheries, analysis of long-term commercial and recreational catch data for white steenbras indicated considerable declines and ultimately stock collapse. Improved catch-per-unit-effort in two large MPAs subsequent to closure confirmed that MPAs can be effective for the protection of white steenbras. However, the current MPA network encompasses a low proportion of sandy shoreline, for which white steenbras exhibits an affinity. Many MPAs do not prohibit recreational shore angling, which currently accounts for the greatest proportion of the total annual catch. Furthermore, EPAs within the juvenile distribution protect a negligible proportion of the total available surface area of estuaries – habitat on which white steenbras is wholly dependent. Despite some evidence of recent increases in abundance in estuaries and the surf zone in certain areas, white steenbras meets the criteria for “Endangered” on the IUCN Red List of Threatened Species, and for “Protected species” status on the National Environmental Management: Biodiversity Act of South Africa. The species requires improved management, with consideration for its life-history style, estuarine dependency, surf zone residency, predictable spawning migrations and its poor conservation status. The multidisciplinary approach provides valuable information towards an improved scientific basis for the management of white steenbras and a framework for research that can be adopted for other overexploited, estuarine-associated coastal fishery species.
- Full Text:
- Date Issued: 2012
- Authors: Bennett, Rhett Hamilton
- Date: 2012
- Subjects: Reef fishes -- Behavior , Endangered species -- South Africa , Fish stock assessment -- South Africa , Fishery management -- South Africa , Fish communities -- South Africa , Sparidae , Lithognathus , Lithognathus -- Growth
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5374 , http://hdl.handle.net/10962/d1015709
- Description: White steenbras Lithognathus lithognathus (Pisces: Sparidae) has been a major target species of numerous fisheries in South Africa, since the late 19th century. Historically, it contributed substantially to annual catches in commercial net fisheries, and became dominant in recreational shore catches in the latter half of the 20th century. However, overexploitation in both sectors resulted in severe declines in abundance. The ultimate collapse of the stock by the end of the last century, and the failure of traditional management measures to protect the species indicate that a new management approach for this species is necessary. The species was identified as a priority for research, management and conservation in a National Linefish Status Report. Despite knowledge on aspects of its biology and life history, little is known about juvenile habitat use patterns, home range dynamics and movement behaviour in estuaries. Similarly, the movement and migration of larger juveniles and adults in the marine environment are poorly understood. Furthermore, there is a complete lack of information on its genetic stock structure. Such information is essential for effective management of a fishery species. This thesis aimed to address the gaps in the understanding of white steenbras movement patterns and genetic stock structure, and provide an assessment of its current conservation status. The study adopted a multidisciplinary approach, incorporating a range of methods and drawing on available information, including published literature, unpublished reports and data from long-term monitoring programmes. Acoustic telemetry, conducted in a range of estuaries, showed high site fidelity, restricted area use, small home ranges relative to the size of the estuary, and a high level of residency within estuaries at the early juvenile life stage. Behaviour within estuaries was dominated by station-keeping, superimposed by a strong diel behaviour, presumably based on feeding and/or predator avoidance, with individuals entering the shallow littoral zone at night to feed, and seeking refuge in the deeper channel areas during the daytime. Conventional dart tagging and recapture data from four ongoing, long-term coastal fish tagging projects, spread throughout the distribution of this species, indicated high levels of residency in the surf zone at the late juvenile and sub-adult life stages. Consequently, juvenile and sub-adult white steenbras are vulnerable to localised depletion, although they can be effectively protected by suitably positioned estuarine protected areas (EPAs) and marine protected areas (MPAs), respectively. It has been hypothesized that adult white steenbras undertake large-scale coastal migrations between summer aggregation areas and winter spawning grounds. The scale of observed coastal movements was correlated with fish size (and age), with larger fish undertaking considerably longer-distance coastal movements than smaller individuals, supporting this hypothesis. Given the migratory behaviour of adults, and indications that limited spawning habitat exists, MPAs designed to protect white steenbras during the adult life stage should encompass all known spawning aggregation sites. The fishery is plagued by problems such as low compliance and low enforcement capacity, and alternative management measures, such as seasonal closure, need to be evaluated. Despite considerable conventional dart tagging effort around the coastline (5 782 fish tagged) with 292 recaptures there remains a lack of empirical evidence of fish migrating long distances (> 600 km) between aggregation and spawning areas. This uncertainty in the level of connectivity among coastal regions was addressed using mitochondrial DNA sequencing and genotyping of microsatellite repeat loci in the nuclear genome, which showed no evidence of major geographic barriers to gene flow in this species. Samples collected throughout the white steenbras core distribution showed high genetic diversity, low genetic differentiation and no evidence of isolation by distance or localised spawning. Although historically dominant in several fisheries, analysis of long-term commercial and recreational catch data for white steenbras indicated considerable declines and ultimately stock collapse. Improved catch-per-unit-effort in two large MPAs subsequent to closure confirmed that MPAs can be effective for the protection of white steenbras. However, the current MPA network encompasses a low proportion of sandy shoreline, for which white steenbras exhibits an affinity. Many MPAs do not prohibit recreational shore angling, which currently accounts for the greatest proportion of the total annual catch. Furthermore, EPAs within the juvenile distribution protect a negligible proportion of the total available surface area of estuaries – habitat on which white steenbras is wholly dependent. Despite some evidence of recent increases in abundance in estuaries and the surf zone in certain areas, white steenbras meets the criteria for “Endangered” on the IUCN Red List of Threatened Species, and for “Protected species” status on the National Environmental Management: Biodiversity Act of South Africa. The species requires improved management, with consideration for its life-history style, estuarine dependency, surf zone residency, predictable spawning migrations and its poor conservation status. The multidisciplinary approach provides valuable information towards an improved scientific basis for the management of white steenbras and a framework for research that can be adopted for other overexploited, estuarine-associated coastal fishery species.
- Full Text:
- Date Issued: 2012
Stakeholder participation in strategic planning processes at three colleges of education in Zimbabwe: towards the development of a participatory process in strategic planning
- Authors: Bhebhe, Gladwin
- Date: 2012
- Subjects: Universities and colleges -- Zimbabwe -- Administration , Universities and colleges -- Zimbabwe , Universities and colleges -- Zimbabwe -- Planning , Education, Higher -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: vital:16186 , http://hdl.handle.net/10353/d1006246 , Universities and colleges -- Zimbabwe -- Administration , Universities and colleges -- Zimbabwe , Universities and colleges -- Zimbabwe -- Planning , Education, Higher -- Zimbabwe
- Description: This study investigated stakeholder participation in strategic planning processes in three teacher training colleges in Zimbabwe. The study was conducted within the qualitative research methodology. Three colleges of education were purposively sampled. All principals in the sampled sites took part in the study. Two Heads of Departments (HODs), two Lecturers in Charge (LICs) two Students Representative Council (SRC) members as well as College Advisory Council Board Members (CACBM) participated in this study. A total of 18 informants participated through interviews. Documents such as strategic planning minutes were scrutinized. Strategic planning meetings were also observed at two sites. The findings were that the practice of strategic planning still appears to be rigid and bureaucratic for organizations that operate in rapidly changing environments such as those in Zimbabwe. Secondly, participation in strategic planning is not all inclusive; only a select few individuals do take part in the planning exercise. Colleges of education and the Ministry focus on the product activities, that is, crafting the strategic plan. They seem to ignore the process activities such as reviewing plans periodically and taking note of key performance indicators which promote continuous improvement. The study also found that participants received no formal training in strategic planning and that the planning process was skewed towards control and compliance; and exhibited managerial accountability tendencies which lie within central bureaucratic approaches. The main recommendations were that the Ministry of Higher and Tertiary Education and the Department of Teacher Education, at the University of Zimbabwe, in consultation with relevant stakeholders should, develop norms and standards for teacher education to align Zimbabwe‟s stakeholder participation in strategic planning to the global trends. Colleges should supplement their understanding of operational contexts by exploring possible future trends and circumstances. The criteria for reviewing strategic plans should be developed by peers, and practitioners in the field, in consultation with national norms and standards for teacher education.
- Full Text:
- Date Issued: 2012
- Authors: Bhebhe, Gladwin
- Date: 2012
- Subjects: Universities and colleges -- Zimbabwe -- Administration , Universities and colleges -- Zimbabwe , Universities and colleges -- Zimbabwe -- Planning , Education, Higher -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: vital:16186 , http://hdl.handle.net/10353/d1006246 , Universities and colleges -- Zimbabwe -- Administration , Universities and colleges -- Zimbabwe , Universities and colleges -- Zimbabwe -- Planning , Education, Higher -- Zimbabwe
- Description: This study investigated stakeholder participation in strategic planning processes in three teacher training colleges in Zimbabwe. The study was conducted within the qualitative research methodology. Three colleges of education were purposively sampled. All principals in the sampled sites took part in the study. Two Heads of Departments (HODs), two Lecturers in Charge (LICs) two Students Representative Council (SRC) members as well as College Advisory Council Board Members (CACBM) participated in this study. A total of 18 informants participated through interviews. Documents such as strategic planning minutes were scrutinized. Strategic planning meetings were also observed at two sites. The findings were that the practice of strategic planning still appears to be rigid and bureaucratic for organizations that operate in rapidly changing environments such as those in Zimbabwe. Secondly, participation in strategic planning is not all inclusive; only a select few individuals do take part in the planning exercise. Colleges of education and the Ministry focus on the product activities, that is, crafting the strategic plan. They seem to ignore the process activities such as reviewing plans periodically and taking note of key performance indicators which promote continuous improvement. The study also found that participants received no formal training in strategic planning and that the planning process was skewed towards control and compliance; and exhibited managerial accountability tendencies which lie within central bureaucratic approaches. The main recommendations were that the Ministry of Higher and Tertiary Education and the Department of Teacher Education, at the University of Zimbabwe, in consultation with relevant stakeholders should, develop norms and standards for teacher education to align Zimbabwe‟s stakeholder participation in strategic planning to the global trends. Colleges should supplement their understanding of operational contexts by exploring possible future trends and circumstances. The criteria for reviewing strategic plans should be developed by peers, and practitioners in the field, in consultation with national norms and standards for teacher education.
- Full Text:
- Date Issued: 2012
Effect of cultivar on the quality of flax and hemp grown in South Africa
- Authors: Blouw, Langa Sunshine
- Date: 2012
- Subjects: Hemp -- South Africa , Flaxseed -- South Africa , Plant varieties , Textile industry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9387 , http://hdl.handle.net/10948/d1010997 , Hemp -- South Africa , Flaxseed -- South Africa , Plant varieties , Textile industry
- Description: Bast fibrous renewable materials, as commercial crops for the manufacture of textile based and other products, have been used for thousands of years to satisfy certain human needs, such as for shelter, clothing, source of energy and tools, and to sustain the livelihood of many communities in countries, such as in Asia, Europe and Africa. Concern for the environment has led to a number of global initiatives that favour the use of natural fibres. It is forecast that the global fibre demand by 2050 will be 130 million tonnes, which the cotton and synthetic fibre production will not be able to meet. Other than the environmental concerns, the renewed global interest in natural fibres, such as flax and hemp, forms part of a strategy to satisfy the fibre demand. South Africa, notwithstanding the fact that the flax and hemp industries have long been established for thousands of years in Europe, Asia and Egypt (Africa), has no history of the breeding, growing, processing and production of these cash crops. The renewed global interest in these crops has also stimulated interest from South Africa with respect to the development of a flax and hemp fibre industry so as to address some of the socio-economic challenges confronting the country today in its attempts to bring about real development in the rural areas through the cultivation and complete beneficiation of these fibre crops. In this regard, the relevant stakeholders, namely government, research councils, tertiary education institutions, farmers and communities worked together to investigate whether South Africa has the agronomic and climatic conditions, technical expertise as well as the necessary processing and production infrastructure to support the development of a local flax and hemp agro-industry. The purpose of this study was firstly to evaluate the performance of EU flax and hemp cultivars grown under different agronomic conditions in South Africa, and their effect on straw biomass yield, fibre yield and total fibre yield per hectare as well as associated fibre properties, and secondly to undertake mechanical fibre modification trials aimed at producing flax and hemp fibres with fibre diameters close to those of cotton. The minimum fibre diameter targeted being 20μm. In accordance with the project objectives and work plan, selected dew retted flax and hemp straw samples from the various planting sites selected by the Agriculture Research Council – Institute for Industrial Crops, representing all the agronomic conditions under investigation, were taken to the CSIR for fibre extraction and testing. A relatively inexpensive and easy to operate Russian designed and manufactured machine, the CMT-200M breaker-cum-scutcher, was used for fibre extraction and the resultant extracted fibre bundles were further refined, using a steel comb, to obtain optimal fibre separation before their physical and chemical properties were evaluated. Results obtained in this research study proved that the climatic and agronomic conditions in South Africa were suitable for the cultivation of flax and hemp, notwithstanding the fact that the fibre yields achieved for hemp were lower than the minimum criteria of 23 percent, and that for flax only just exceeded the 25 percent minimum. The lack of local technical expertise on the growing and retting of flax and hemp, contributed to the low fibre yields. The planting parameters which were found to produce good results for the cultivation of hemp were the October planting date, using a row spacing of between 12.5 to 25 cm, with a seeding density of between 80 – 100kg, and the application of 50 – 100kg nitrogen fertiliser. The use of extra artificial lighting and herbicide treatment did not appear to beneficially improve the hemp fibre yields. Similar considerations for flax cultivation in the Southern Cape region, particularly Oudtshoorn and Outeniqua, indicated that May to July planting dates, using inter-row spacing of 25cm and sowing density of 63kg seed.haˉ¹, produced a fibre yield and total fibre yield per hectare above the minimum values of 25 percent and 0,8 tonnes per hectare, respectively, quoted in the literature.
- Full Text:
- Date Issued: 2012
- Authors: Blouw, Langa Sunshine
- Date: 2012
- Subjects: Hemp -- South Africa , Flaxseed -- South Africa , Plant varieties , Textile industry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9387 , http://hdl.handle.net/10948/d1010997 , Hemp -- South Africa , Flaxseed -- South Africa , Plant varieties , Textile industry
- Description: Bast fibrous renewable materials, as commercial crops for the manufacture of textile based and other products, have been used for thousands of years to satisfy certain human needs, such as for shelter, clothing, source of energy and tools, and to sustain the livelihood of many communities in countries, such as in Asia, Europe and Africa. Concern for the environment has led to a number of global initiatives that favour the use of natural fibres. It is forecast that the global fibre demand by 2050 will be 130 million tonnes, which the cotton and synthetic fibre production will not be able to meet. Other than the environmental concerns, the renewed global interest in natural fibres, such as flax and hemp, forms part of a strategy to satisfy the fibre demand. South Africa, notwithstanding the fact that the flax and hemp industries have long been established for thousands of years in Europe, Asia and Egypt (Africa), has no history of the breeding, growing, processing and production of these cash crops. The renewed global interest in these crops has also stimulated interest from South Africa with respect to the development of a flax and hemp fibre industry so as to address some of the socio-economic challenges confronting the country today in its attempts to bring about real development in the rural areas through the cultivation and complete beneficiation of these fibre crops. In this regard, the relevant stakeholders, namely government, research councils, tertiary education institutions, farmers and communities worked together to investigate whether South Africa has the agronomic and climatic conditions, technical expertise as well as the necessary processing and production infrastructure to support the development of a local flax and hemp agro-industry. The purpose of this study was firstly to evaluate the performance of EU flax and hemp cultivars grown under different agronomic conditions in South Africa, and their effect on straw biomass yield, fibre yield and total fibre yield per hectare as well as associated fibre properties, and secondly to undertake mechanical fibre modification trials aimed at producing flax and hemp fibres with fibre diameters close to those of cotton. The minimum fibre diameter targeted being 20μm. In accordance with the project objectives and work plan, selected dew retted flax and hemp straw samples from the various planting sites selected by the Agriculture Research Council – Institute for Industrial Crops, representing all the agronomic conditions under investigation, were taken to the CSIR for fibre extraction and testing. A relatively inexpensive and easy to operate Russian designed and manufactured machine, the CMT-200M breaker-cum-scutcher, was used for fibre extraction and the resultant extracted fibre bundles were further refined, using a steel comb, to obtain optimal fibre separation before their physical and chemical properties were evaluated. Results obtained in this research study proved that the climatic and agronomic conditions in South Africa were suitable for the cultivation of flax and hemp, notwithstanding the fact that the fibre yields achieved for hemp were lower than the minimum criteria of 23 percent, and that for flax only just exceeded the 25 percent minimum. The lack of local technical expertise on the growing and retting of flax and hemp, contributed to the low fibre yields. The planting parameters which were found to produce good results for the cultivation of hemp were the October planting date, using a row spacing of between 12.5 to 25 cm, with a seeding density of between 80 – 100kg, and the application of 50 – 100kg nitrogen fertiliser. The use of extra artificial lighting and herbicide treatment did not appear to beneficially improve the hemp fibre yields. Similar considerations for flax cultivation in the Southern Cape region, particularly Oudtshoorn and Outeniqua, indicated that May to July planting dates, using inter-row spacing of 25cm and sowing density of 63kg seed.haˉ¹, produced a fibre yield and total fibre yield per hectare above the minimum values of 25 percent and 0,8 tonnes per hectare, respectively, quoted in the literature.
- Full Text:
- Date Issued: 2012
Teaching pharmacology: issues of language and learning in a multilingual classroom setting
- Boschmans, Shirley-Anne Inez
- Authors: Boschmans, Shirley-Anne Inez
- Date: 2012
- Subjects: English language -- Study and teaching -- South Africa , Pharmacology -- Terminology , Multicultural education , Second language acquisition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9562 , http://hdl.handle.net/10948/d1013398
- Description: The medium for teaching and learning in South African universities is not the mother tongue of the majority of students and this has been reported to be a barrier to achievement (Department of Education, 2002). Poor English language skills, as well as poor discipline specific vocabulary knowledge, can lead to poor study techniques with the students resorting to rote learning as they are unable to interpret the recommended texts (Gow, Kember, & Chow, 1991; Shembe, 2002). In 2005 at the NMMU a significant difference was reported between the marks achieved for the Pharmacology 2 (ZCL2) module by English first language (EFL) students and the English second language students (EAL) (Boschmans & McCartney, 2005). These finding provided motivation for this study which interrogates issues of language and learning in a multilingual Pharmacology classroom. A mixed methods approach, which employed a concurrent triangulation design with quantitative dominance, was used. Two parallel studies were undertaken. One consisted of a quasi-experimental, pre-test and post-test control group design using an intervention which consisted of the application of the didactical practice of exploratory talk with an experimental sample group during ZCL2 Supplementary Instruction sessions (SI). A second study involved a parallel data collection from the ZCL303 and ZCL401 Pharmacy students at the NMMU to investigate possible effects of academic progression. Purposive, homogenous sampling was used in selection of the samples. The mean ZCL2 mark for the experimental group (58.70±14.14 percent) of students who experienced the intervention (application of exploratory talk) was significantly higher (p = .0004) than the mark achieved by the ZCL2 comparison group (46.47±14.48). This Abstract difference was of high practical significance (Cohen‟s d = 0.85). This quantitative finding was supported by the qualitative data where the students expressed support for the discussion sessions (application of exploratory talk) held during SI sessions. There was a significant increase, with academic progression, of English reading comprehension amongst the EFL students (p = .025) but not in the EAL students and BPharm1 weighted average (p < .001) as well as SI attendance (p = .02) correlated significantly with achievement in ZCL2. The findings of this study provide insights into the teaching of Pharmacology in a multilingual classroom. The qualitative results in addition to strengthening the quantitative findings through triangulation have provided a rich, deep and detailed description of the lived experiences of Pharmacology students. The data will provide insights into students‟ experiences for Pharmacy academics and are a resource for understanding student perspectives.
- Full Text:
- Date Issued: 2012
- Authors: Boschmans, Shirley-Anne Inez
- Date: 2012
- Subjects: English language -- Study and teaching -- South Africa , Pharmacology -- Terminology , Multicultural education , Second language acquisition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9562 , http://hdl.handle.net/10948/d1013398
- Description: The medium for teaching and learning in South African universities is not the mother tongue of the majority of students and this has been reported to be a barrier to achievement (Department of Education, 2002). Poor English language skills, as well as poor discipline specific vocabulary knowledge, can lead to poor study techniques with the students resorting to rote learning as they are unable to interpret the recommended texts (Gow, Kember, & Chow, 1991; Shembe, 2002). In 2005 at the NMMU a significant difference was reported between the marks achieved for the Pharmacology 2 (ZCL2) module by English first language (EFL) students and the English second language students (EAL) (Boschmans & McCartney, 2005). These finding provided motivation for this study which interrogates issues of language and learning in a multilingual Pharmacology classroom. A mixed methods approach, which employed a concurrent triangulation design with quantitative dominance, was used. Two parallel studies were undertaken. One consisted of a quasi-experimental, pre-test and post-test control group design using an intervention which consisted of the application of the didactical practice of exploratory talk with an experimental sample group during ZCL2 Supplementary Instruction sessions (SI). A second study involved a parallel data collection from the ZCL303 and ZCL401 Pharmacy students at the NMMU to investigate possible effects of academic progression. Purposive, homogenous sampling was used in selection of the samples. The mean ZCL2 mark for the experimental group (58.70±14.14 percent) of students who experienced the intervention (application of exploratory talk) was significantly higher (p = .0004) than the mark achieved by the ZCL2 comparison group (46.47±14.48). This Abstract difference was of high practical significance (Cohen‟s d = 0.85). This quantitative finding was supported by the qualitative data where the students expressed support for the discussion sessions (application of exploratory talk) held during SI sessions. There was a significant increase, with academic progression, of English reading comprehension amongst the EFL students (p = .025) but not in the EAL students and BPharm1 weighted average (p < .001) as well as SI attendance (p = .02) correlated significantly with achievement in ZCL2. The findings of this study provide insights into the teaching of Pharmacology in a multilingual classroom. The qualitative results in addition to strengthening the quantitative findings through triangulation have provided a rich, deep and detailed description of the lived experiences of Pharmacology students. The data will provide insights into students‟ experiences for Pharmacy academics and are a resource for understanding student perspectives.
- Full Text:
- Date Issued: 2012
An analysis of the Southern African Development Community (SADC) preventive diplomacy in the kingdom of Lesotho: a case study
- Authors: Bukae, Nkosi Makhonya
- Date: 2012
- Subjects: Southern African Development Community , Diplomatic negotiations in international disputes , Diplomacy , Conflict management -- Lesotho , Africa, Southern -- Politics and government , Lesotho -- Politics and government
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8196 , http://hdl.handle.net/10948/d1008296 , Southern African Development Community , Diplomatic negotiations in international disputes , Diplomacy , Conflict management -- Lesotho , Africa, Southern -- Politics and government , Lesotho -- Politics and government
- Description: The focus of this study is the Southern African Development Community (SADC) preventive diplomacy interventions in Lesotho in 1994, 1998 and 2007. The core aim of the study was to evaluate the efficacy of the SADC security mechanism (the Organ on Politics, Defence and Security (OPDS) in conflict prevention, management and resolution on the basis of the Lesotho experience. Data for this qualitative case study was collected through interviews and document analysis. The twenty four participants for the study were drawn from the SADC OPDS unit, Lesotho political parties, Civil Society Organisations (CSOs), Academics from the University of Botswana (UB) and the National University of Lesotho (NUL), retired Botswana Defence officers who participated in the Lesotho missions and office of the post-2007election dispute dialogue facilitator in Lesotho. Documents on the SADC Treaties, Protocols, Communiqués and interventions in other set ups were used to highlight its operational policies, mandate, structures, successes and challenges. Lesotho was chosen as a case study because SADC employed both non-coercive (SADC Troika and Eminent Person mediation, 1994 and 2007 respectively) and coercive measures (the 1998 military intervention). The findings of the study revealed that SADC as a regional body had its own successes and challenges. Different perceptions on the SADC interventions in Lesotho emerged mainly between the participants from the ruling party and the opposition parties. While the former commended SADC for successfully mitigating the calamitous effects of 1994, 1998 and 2007 post-electoral violence, the opposition parties viewed the regional organisations as engaged in illegal interference in the domestic affairs of the country to defend the incumbent governing party. It also emerged from the study that the SADC security mechanism has numerous structural and operational flaws. There were several unanswered questions revolving around the legality and mandate of some of the missions. For instance, no concrete evidence emerged as to whether the 1998 military intervention was authorised by the SADC. The study also revealed that SADC has learnt valuable lessons from the Lesotho missions. Some of the reforms which the SADC has introduced in the OPDS such as the establishment of the SADC Stand by Force, Early Warning structures, the Mediation Unit, and a panel of expert mediators emanated mainly from the Lesotho experiences. The study recommends that SADC needs to harmonise the efforts of its OPDS structures such as the Mediation Unit; the Troika; the Inter-State Defence and Security Committee (ISDSC); the Inter-State Politics and Diplomacy Committee (ISPDC) and the Summit of Heads of States and Governments for rapid, coherent and well coordinated interventions in future regional preventive missions. It is also recommended that SADC should focus on identifying and mitigating underlying causal factors such as underdevelopment; poverty; deprivation of freedoms, marginalisation and other forms of social stratifications and oppression in its preventive diplomacy missions if durable peace is to be achieved in Lesotho and any other future cases.
- Full Text:
- Date Issued: 2012
- Authors: Bukae, Nkosi Makhonya
- Date: 2012
- Subjects: Southern African Development Community , Diplomatic negotiations in international disputes , Diplomacy , Conflict management -- Lesotho , Africa, Southern -- Politics and government , Lesotho -- Politics and government
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8196 , http://hdl.handle.net/10948/d1008296 , Southern African Development Community , Diplomatic negotiations in international disputes , Diplomacy , Conflict management -- Lesotho , Africa, Southern -- Politics and government , Lesotho -- Politics and government
- Description: The focus of this study is the Southern African Development Community (SADC) preventive diplomacy interventions in Lesotho in 1994, 1998 and 2007. The core aim of the study was to evaluate the efficacy of the SADC security mechanism (the Organ on Politics, Defence and Security (OPDS) in conflict prevention, management and resolution on the basis of the Lesotho experience. Data for this qualitative case study was collected through interviews and document analysis. The twenty four participants for the study were drawn from the SADC OPDS unit, Lesotho political parties, Civil Society Organisations (CSOs), Academics from the University of Botswana (UB) and the National University of Lesotho (NUL), retired Botswana Defence officers who participated in the Lesotho missions and office of the post-2007election dispute dialogue facilitator in Lesotho. Documents on the SADC Treaties, Protocols, Communiqués and interventions in other set ups were used to highlight its operational policies, mandate, structures, successes and challenges. Lesotho was chosen as a case study because SADC employed both non-coercive (SADC Troika and Eminent Person mediation, 1994 and 2007 respectively) and coercive measures (the 1998 military intervention). The findings of the study revealed that SADC as a regional body had its own successes and challenges. Different perceptions on the SADC interventions in Lesotho emerged mainly between the participants from the ruling party and the opposition parties. While the former commended SADC for successfully mitigating the calamitous effects of 1994, 1998 and 2007 post-electoral violence, the opposition parties viewed the regional organisations as engaged in illegal interference in the domestic affairs of the country to defend the incumbent governing party. It also emerged from the study that the SADC security mechanism has numerous structural and operational flaws. There were several unanswered questions revolving around the legality and mandate of some of the missions. For instance, no concrete evidence emerged as to whether the 1998 military intervention was authorised by the SADC. The study also revealed that SADC has learnt valuable lessons from the Lesotho missions. Some of the reforms which the SADC has introduced in the OPDS such as the establishment of the SADC Stand by Force, Early Warning structures, the Mediation Unit, and a panel of expert mediators emanated mainly from the Lesotho experiences. The study recommends that SADC needs to harmonise the efforts of its OPDS structures such as the Mediation Unit; the Troika; the Inter-State Defence and Security Committee (ISDSC); the Inter-State Politics and Diplomacy Committee (ISPDC) and the Summit of Heads of States and Governments for rapid, coherent and well coordinated interventions in future regional preventive missions. It is also recommended that SADC should focus on identifying and mitigating underlying causal factors such as underdevelopment; poverty; deprivation of freedoms, marginalisation and other forms of social stratifications and oppression in its preventive diplomacy missions if durable peace is to be achieved in Lesotho and any other future cases.
- Full Text:
- Date Issued: 2012
Marketers' perceptions of negotiation behaviour in a global scale
- Authors: Burhan, Ahmad Mtengwa
- Date: 2012
- Subjects: Negotiation in business -- Tanzania , Business enterprises -- Tanzania , Export marketing -- Tanzania
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:9297 , http://hdl.handle.net/10948/d1013705
- Description: The success of international business depends on effective negotiations. Such negotiations do no happen in a vacuum, but usually in a specific environment that includes; time, surrounding, place, culture and people. The business environmental setting includes legal and political pluralism, currency fluctuations, foreign exchange, foreign government controls, bureaucracy, instability, change, ideological and cultural differences, as well as the influence of external stakeholders. These business negotiations environments can influence the behaviour of negotiation in global firms, impacting firms internationally. The reasons to negotiate on an international level may include considerations such as: choice of venue, culture to observe; and the outcome of the negotiation process. The aim of this study was to determine the influence of the international marketing environment, awareness of negotiation skill, interest groups and negotiation atmosphere on behaviour of marketers in a global firm. The study assessed the impact of negotiation behaviour on business agreements based on trust and certainty and level of commitment. The purpose of the study was to gauge the impact of negotiations behaviour pertaining to failure of business negotiations in Tanzania. In addition, the study endeavoured to determine the impact of environmental variables on the negotiation behaviour of marketers. The questionnaires used in the study comprised seven variables with statements linked to a five-point Likert-type interval scale varying from “strongly agree” to “strongly disagree. Self-administered questionnaires were used for data collection from global firms’ marketers and their management representatives; 323 questionnaires were collected from respondents. This study contributed to the literature on negotiation behaviour in a global firm and the perceptions of such global marketers in Tanzania. Many international companies in Tanzania find it difficult to formulate and implement a comprehensive business strategy; therefore, this study intends to equip international business managers with the leadership skills required. Based on the findings of this study, the negotiators and government are expected to play a major role in business negotiations to promote effective trade agreements despite limitations of political influence in the negotiation process. Political stability in a country enhances foreign business which in turn improves negotiation behaviour. A just legal system, with clear and unambiguous business guidelines and policies would benefit and promote local businesses and government representatives and negotiators in respect of international business negotiation behaviour. Reasonable tax and interest rates and fair business policies should improve international trade negotiations and business practices. In order to conduct successful international negotiations aspects such as culture, language differences, customs and traditions are important and should enjoy high priority. Aspects such as these mentioned influence the conducting and atmosphere and outcome of negotiations. The study reveals that the use of specialists and interpreters are imperative to guarantee understanding and successful outcomes. According to the findings negotiators should possess good negotiating skills to be able to steer the negotiation process through the different phases of negotiation that requires different negotiating skills at each stage of negotiation. It is clear that to have successful win-win negotiation outcomes the leading negotiator should put together a good team, with expert knowledge of product or conditions and negotiating skill, as well as possessing the attributes mentioned in the previous paragraph. The negotiator should also be able to determine authority limits, patience and observe negotiation ethics. No team disagreements concerning the business/project matters should be aired in front of counterparts during negotiations and professional conduct must prevail at all times. The findings of the study indicated that awareness of the practice of offering concessions regarding government tariff laws and price discounts that is in line with traditions in Tanzania. Concessions should not be made until all issues have been discussed, to avoid granting unnecessary benefits during negotiation that might be interpreted as bribery. This study concluded that it is important that marketers meet the requirements of business practices by sharing clear guidelines and policies regarding business practices, as this will lead to fruitful decisions. It was also found that negotiation behaviour improves when negotiators are willing to share information and agree that all communication must be in writing; marketers are more comfortable when there is a clear understanding of matters agreed upon, the choice of trading partners and that all trading agreements are written and a contract signed by all the parties, including governments where necessary. Marketers’ intentions are derived from the common interests of both parties and the negotiations should always take place in avenue that is suitable to both parties, conducted in fairness and offers must be reasonable and attainable with a positive outcome as the ultimate aim for both parties. This study reveals that negotiators insist on the use an agent or agents and sub-contractors to ensure mutually beneficial strategic business partnerships. However, when the role of the interest groups is explained to all participants, negotiation behaviour improves. It can also be concluded that negotiators allow interest groups to participate as team leaders and their number should be equal to the number of foreign negotiators, to ensure that marketers feel more at ease and comfortable to participate. An atmosphere based on bargaining power exerts a positive influence on the level of commitment among negotiating partners; and can be a predictor of the range of agreement as well as shape limits and priorities among dimensions of rivalry. However, it is important for marketers to express willingness to accept the terms of their counterpart’s bargaining zone regardless of non-profitable quotas at stake; identify areas of bargaining from foreign traders even if they are not attractive enough for local traders and are comfortable with the counterparts’ bargaining zone regarding fixed rates on exporting and importing quotas between trading partners to build trust among negotiators. In conclusion, it was found that negotiation behaviour has a positive influence on the level of commitment of trading partners. A positive business relationship is created on trust and a high-level of commitment which should be of great satisfaction to negotiating parties for future prospective negotiations.
- Full Text:
- Date Issued: 2012
- Authors: Burhan, Ahmad Mtengwa
- Date: 2012
- Subjects: Negotiation in business -- Tanzania , Business enterprises -- Tanzania , Export marketing -- Tanzania
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:9297 , http://hdl.handle.net/10948/d1013705
- Description: The success of international business depends on effective negotiations. Such negotiations do no happen in a vacuum, but usually in a specific environment that includes; time, surrounding, place, culture and people. The business environmental setting includes legal and political pluralism, currency fluctuations, foreign exchange, foreign government controls, bureaucracy, instability, change, ideological and cultural differences, as well as the influence of external stakeholders. These business negotiations environments can influence the behaviour of negotiation in global firms, impacting firms internationally. The reasons to negotiate on an international level may include considerations such as: choice of venue, culture to observe; and the outcome of the negotiation process. The aim of this study was to determine the influence of the international marketing environment, awareness of negotiation skill, interest groups and negotiation atmosphere on behaviour of marketers in a global firm. The study assessed the impact of negotiation behaviour on business agreements based on trust and certainty and level of commitment. The purpose of the study was to gauge the impact of negotiations behaviour pertaining to failure of business negotiations in Tanzania. In addition, the study endeavoured to determine the impact of environmental variables on the negotiation behaviour of marketers. The questionnaires used in the study comprised seven variables with statements linked to a five-point Likert-type interval scale varying from “strongly agree” to “strongly disagree. Self-administered questionnaires were used for data collection from global firms’ marketers and their management representatives; 323 questionnaires were collected from respondents. This study contributed to the literature on negotiation behaviour in a global firm and the perceptions of such global marketers in Tanzania. Many international companies in Tanzania find it difficult to formulate and implement a comprehensive business strategy; therefore, this study intends to equip international business managers with the leadership skills required. Based on the findings of this study, the negotiators and government are expected to play a major role in business negotiations to promote effective trade agreements despite limitations of political influence in the negotiation process. Political stability in a country enhances foreign business which in turn improves negotiation behaviour. A just legal system, with clear and unambiguous business guidelines and policies would benefit and promote local businesses and government representatives and negotiators in respect of international business negotiation behaviour. Reasonable tax and interest rates and fair business policies should improve international trade negotiations and business practices. In order to conduct successful international negotiations aspects such as culture, language differences, customs and traditions are important and should enjoy high priority. Aspects such as these mentioned influence the conducting and atmosphere and outcome of negotiations. The study reveals that the use of specialists and interpreters are imperative to guarantee understanding and successful outcomes. According to the findings negotiators should possess good negotiating skills to be able to steer the negotiation process through the different phases of negotiation that requires different negotiating skills at each stage of negotiation. It is clear that to have successful win-win negotiation outcomes the leading negotiator should put together a good team, with expert knowledge of product or conditions and negotiating skill, as well as possessing the attributes mentioned in the previous paragraph. The negotiator should also be able to determine authority limits, patience and observe negotiation ethics. No team disagreements concerning the business/project matters should be aired in front of counterparts during negotiations and professional conduct must prevail at all times. The findings of the study indicated that awareness of the practice of offering concessions regarding government tariff laws and price discounts that is in line with traditions in Tanzania. Concessions should not be made until all issues have been discussed, to avoid granting unnecessary benefits during negotiation that might be interpreted as bribery. This study concluded that it is important that marketers meet the requirements of business practices by sharing clear guidelines and policies regarding business practices, as this will lead to fruitful decisions. It was also found that negotiation behaviour improves when negotiators are willing to share information and agree that all communication must be in writing; marketers are more comfortable when there is a clear understanding of matters agreed upon, the choice of trading partners and that all trading agreements are written and a contract signed by all the parties, including governments where necessary. Marketers’ intentions are derived from the common interests of both parties and the negotiations should always take place in avenue that is suitable to both parties, conducted in fairness and offers must be reasonable and attainable with a positive outcome as the ultimate aim for both parties. This study reveals that negotiators insist on the use an agent or agents and sub-contractors to ensure mutually beneficial strategic business partnerships. However, when the role of the interest groups is explained to all participants, negotiation behaviour improves. It can also be concluded that negotiators allow interest groups to participate as team leaders and their number should be equal to the number of foreign negotiators, to ensure that marketers feel more at ease and comfortable to participate. An atmosphere based on bargaining power exerts a positive influence on the level of commitment among negotiating partners; and can be a predictor of the range of agreement as well as shape limits and priorities among dimensions of rivalry. However, it is important for marketers to express willingness to accept the terms of their counterpart’s bargaining zone regardless of non-profitable quotas at stake; identify areas of bargaining from foreign traders even if they are not attractive enough for local traders and are comfortable with the counterparts’ bargaining zone regarding fixed rates on exporting and importing quotas between trading partners to build trust among negotiators. In conclusion, it was found that negotiation behaviour has a positive influence on the level of commitment of trading partners. A positive business relationship is created on trust and a high-level of commitment which should be of great satisfaction to negotiating parties for future prospective negotiations.
- Full Text:
- Date Issued: 2012
Self-perceived professional identity of pharmacy educators
- Authors: Burton, Susan
- Date: 2012
- Subjects: Academic identity , Communities of practice , Identity (Philosophical concept) , Pharmacy -- Study and teaching , Pharmacy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10139 , http://hdl.handle.net/10948/d1008352 , Academic identity , Communities of practice , Identity (Philosophical concept) , Pharmacy -- Study and teaching , Pharmacy
- Description: The philosophy of pharmaceutical care, which defines a patient-centred approach to practice, has been embraced and upheld by national and international pharmaceutical organisations for two decades. However, pharmacists have been slow to change their practice and implement a pharmaceutical care approach. It has been suggested that amongst other factors, short-comings in pharmaceutical education have contributed to this reluctance of the profession to transform practice. Efforts to address these short-comings in pharmaceutical education have focused on the curriculum and pedagogic practices, and not on the pharmacy educators themselves. Palmer (1998) asserts that “good teaching cannot be reduced to technique; good teaching comes from the identity and integrity of the teacher”. In essence, "we teach who we are" and good teachers have one common trait: “a strong sense of personal identity that infuses their work”. This study identified, described and analysed the self-perceived professional identities of pharmacy educators within the South African context. This included ascertaining factors and contexts which contributed to participants’ self-perception of their professional identity. In an effort to understand the influence the educators have on practice and on changing practice and vice-versa, the attitudes, beliefs and behaviours of participants regarding the philosophy and practice of pharmaceutical care, and pharmaceutical education were also explored. Situated within a constructivist-interpretive, qualitative paradigm and making use of methodological triangulation, this study was conducted in three phases, each employing a different qualitative method to collect data. The first phase made use of narrative analysis to gain an in-depth understanding of pharmacy educators’ perceived professional identities and to explore how their experiences, across various contexts, have formed their professional identities. In-depth individual narrative interviews were used to provide a forum in which the participants could reflect upon and tell their professional life-story. This phase of the study also made use of the exploration of metaphors to further investigate the participants’ professional identity and, more particularly, their images of themselves as “teacher” and role model for students. A maximum variation, purposeful sampling approach was used to recruit eight pharmacy academics - one from each school or faculty of pharmacy in South Africa, as participants in this phase of the study. The second and third phases explored more widely, the insights gained from the first phase and the formation of professional identity, attitudes, beliefs and practices of pharmacy educators in South Africa. Two focus groups were employed during the second phase and the study sample was broadened to include a further ten pharmacy educators. In the third phase, a purpose-designed, qualitative questionnaire was used to extend the study sample to all pharmacy educators in South Africa. A convenience sampling approach was used in both the second and third phases of the study. Thematic analysis and interpretation of the narrative interview and focus group transcripts and the questionnaire responses were conducted using qualitative data analysis software – Atlas.ti®. A multiplicity of self-perceived professional identities was described. However, all of these were multi-faceted and could be situated on a continuum between pharmacist identity on one end and academic identity on the other. In addition, six key determinants were recognised as underpinning the participants’ self-perception of their professional identity. These included three structural determinants: expected role; knowledge base; and practice, and three determinants relating to the emotional dimensions and agency of professional identity: professional status; passions; and satisfiers. The professional identity of the participants had been formed through membership of multiple pharmacy-related communities of practice and continued to be sustained through a nexus of multi-membership. There was extensive support by the participants for the concept of pharmaceutical care; however, it did not impact extensively on their role as pharmacy educators. Furthermore, many expressed concern around the use of the term ‘pharmaceutical care’: its definition; its lack of penetration into, and implementation within the practice environment; and even its relevance to the South African healthcare context. Many of the participants perceived the professional development of future pharmacists to be integral to their role as educators, and was often their source of greatest professional satisfaction. However, concern was also expressed at the dissonance that students were perceived to experience, sometimes, because of the incongruities that they are taught and what they experience in practice. This study has afforded pharmacy educators in South Africa an opportunity to understand better “who” they are as professionals, and to reflect on their role as educators and as role models for future pharmacist. Moreover, the findings contribute to a collective understanding of the professional identity of pharmacy educators and socialisation of pharmacy students into the profession. The insights and recommendations emerging from the study have the potential to make academic pharmacy a more attractive career choice which may have positive implications for the future attraction and retention of pharmacists to academic posts within universities.
- Full Text:
- Date Issued: 2012
- Authors: Burton, Susan
- Date: 2012
- Subjects: Academic identity , Communities of practice , Identity (Philosophical concept) , Pharmacy -- Study and teaching , Pharmacy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10139 , http://hdl.handle.net/10948/d1008352 , Academic identity , Communities of practice , Identity (Philosophical concept) , Pharmacy -- Study and teaching , Pharmacy
- Description: The philosophy of pharmaceutical care, which defines a patient-centred approach to practice, has been embraced and upheld by national and international pharmaceutical organisations for two decades. However, pharmacists have been slow to change their practice and implement a pharmaceutical care approach. It has been suggested that amongst other factors, short-comings in pharmaceutical education have contributed to this reluctance of the profession to transform practice. Efforts to address these short-comings in pharmaceutical education have focused on the curriculum and pedagogic practices, and not on the pharmacy educators themselves. Palmer (1998) asserts that “good teaching cannot be reduced to technique; good teaching comes from the identity and integrity of the teacher”. In essence, "we teach who we are" and good teachers have one common trait: “a strong sense of personal identity that infuses their work”. This study identified, described and analysed the self-perceived professional identities of pharmacy educators within the South African context. This included ascertaining factors and contexts which contributed to participants’ self-perception of their professional identity. In an effort to understand the influence the educators have on practice and on changing practice and vice-versa, the attitudes, beliefs and behaviours of participants regarding the philosophy and practice of pharmaceutical care, and pharmaceutical education were also explored. Situated within a constructivist-interpretive, qualitative paradigm and making use of methodological triangulation, this study was conducted in three phases, each employing a different qualitative method to collect data. The first phase made use of narrative analysis to gain an in-depth understanding of pharmacy educators’ perceived professional identities and to explore how their experiences, across various contexts, have formed their professional identities. In-depth individual narrative interviews were used to provide a forum in which the participants could reflect upon and tell their professional life-story. This phase of the study also made use of the exploration of metaphors to further investigate the participants’ professional identity and, more particularly, their images of themselves as “teacher” and role model for students. A maximum variation, purposeful sampling approach was used to recruit eight pharmacy academics - one from each school or faculty of pharmacy in South Africa, as participants in this phase of the study. The second and third phases explored more widely, the insights gained from the first phase and the formation of professional identity, attitudes, beliefs and practices of pharmacy educators in South Africa. Two focus groups were employed during the second phase and the study sample was broadened to include a further ten pharmacy educators. In the third phase, a purpose-designed, qualitative questionnaire was used to extend the study sample to all pharmacy educators in South Africa. A convenience sampling approach was used in both the second and third phases of the study. Thematic analysis and interpretation of the narrative interview and focus group transcripts and the questionnaire responses were conducted using qualitative data analysis software – Atlas.ti®. A multiplicity of self-perceived professional identities was described. However, all of these were multi-faceted and could be situated on a continuum between pharmacist identity on one end and academic identity on the other. In addition, six key determinants were recognised as underpinning the participants’ self-perception of their professional identity. These included three structural determinants: expected role; knowledge base; and practice, and three determinants relating to the emotional dimensions and agency of professional identity: professional status; passions; and satisfiers. The professional identity of the participants had been formed through membership of multiple pharmacy-related communities of practice and continued to be sustained through a nexus of multi-membership. There was extensive support by the participants for the concept of pharmaceutical care; however, it did not impact extensively on their role as pharmacy educators. Furthermore, many expressed concern around the use of the term ‘pharmaceutical care’: its definition; its lack of penetration into, and implementation within the practice environment; and even its relevance to the South African healthcare context. Many of the participants perceived the professional development of future pharmacists to be integral to their role as educators, and was often their source of greatest professional satisfaction. However, concern was also expressed at the dissonance that students were perceived to experience, sometimes, because of the incongruities that they are taught and what they experience in practice. This study has afforded pharmacy educators in South Africa an opportunity to understand better “who” they are as professionals, and to reflect on their role as educators and as role models for future pharmacist. Moreover, the findings contribute to a collective understanding of the professional identity of pharmacy educators and socialisation of pharmacy students into the profession. The insights and recommendations emerging from the study have the potential to make academic pharmacy a more attractive career choice which may have positive implications for the future attraction and retention of pharmacists to academic posts within universities.
- Full Text:
- Date Issued: 2012
A model for automated topic spotting in a mobile chat based mathematics tutoring environment
- Authors: Butgereit, Laura Lee
- Date: 2012
- Subjects: Mobile communication systems in education , Mathematics -- Study and teaching , Tutors and tutoring -- Mathematics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9809 , http://hdl.handle.net/10948/d1013741
- Description: Systems of writing have existed for thousands of years. The history of civilisation and the history of writing are so intertwined that it is hard to separate the one from the other. These systems of writing, however, are not static. They change. One of the latest developments in systems of writing is short electronic messages such as seen on Twitter and in MXit. One novel application which uses these short electronic messages is the Dr Math® project. Dr Math is a mobile online tutoring system where pupils can use MXit on their cell phones and receive help with their mathematics homework from volunteer tutors around the world. These conversations between pupils and tutors are held in MXit lingo or MXit language – this cryptic, abbreviated system 0f ryting w1ch l0ks lyk dis. Project μ (pronounced mu and indicating MXit Understander) investigated how topics could be determined in MXit lingo and Project μ's research outputs spot mathematics topics in conversations between Dr Math tutors and pupils. Once the topics are determined, supporting documentation can be presented to the tutors to assist them in helping pupils with their mathematics homework. Project μ made the following contributions to new knowledge: a statistical and linguistic analysis of MXit lingo provides letter frequencies, word frequencies, message length statistics as well as linguistic bases for new spelling conventions seen in MXit based conversations; a post-stemmer for use with MXit lingo removes suffixes from the ends of words taking into account MXit spelling conventions allowing words such as equashun and equation to be reduced to the same root stem; a list of over ten thousand stop words for MXit lingo appropriate for the domain of mathematics; a misspelling corrector for MXit lingo which corrects words such as acount and equates it to account; and a model for spotting mathematical topics in MXit lingo. The model was instantiated and integrated into the Dr Math tutoring platform. Empirical evidence as to the effectiveness of the μ Topic Spotter and the other contributions is also presented. The empirical evidence includes specific statistical tests with MXit lingo, specific tests of the misspelling corrector, stemmer, and feedback mechanism, and an extensive exercise of content analysis with respect to mathematics topics.
- Full Text:
- Date Issued: 2012
- Authors: Butgereit, Laura Lee
- Date: 2012
- Subjects: Mobile communication systems in education , Mathematics -- Study and teaching , Tutors and tutoring -- Mathematics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9809 , http://hdl.handle.net/10948/d1013741
- Description: Systems of writing have existed for thousands of years. The history of civilisation and the history of writing are so intertwined that it is hard to separate the one from the other. These systems of writing, however, are not static. They change. One of the latest developments in systems of writing is short electronic messages such as seen on Twitter and in MXit. One novel application which uses these short electronic messages is the Dr Math® project. Dr Math is a mobile online tutoring system where pupils can use MXit on their cell phones and receive help with their mathematics homework from volunteer tutors around the world. These conversations between pupils and tutors are held in MXit lingo or MXit language – this cryptic, abbreviated system 0f ryting w1ch l0ks lyk dis. Project μ (pronounced mu and indicating MXit Understander) investigated how topics could be determined in MXit lingo and Project μ's research outputs spot mathematics topics in conversations between Dr Math tutors and pupils. Once the topics are determined, supporting documentation can be presented to the tutors to assist them in helping pupils with their mathematics homework. Project μ made the following contributions to new knowledge: a statistical and linguistic analysis of MXit lingo provides letter frequencies, word frequencies, message length statistics as well as linguistic bases for new spelling conventions seen in MXit based conversations; a post-stemmer for use with MXit lingo removes suffixes from the ends of words taking into account MXit spelling conventions allowing words such as equashun and equation to be reduced to the same root stem; a list of over ten thousand stop words for MXit lingo appropriate for the domain of mathematics; a misspelling corrector for MXit lingo which corrects words such as acount and equates it to account; and a model for spotting mathematical topics in MXit lingo. The model was instantiated and integrated into the Dr Math tutoring platform. Empirical evidence as to the effectiveness of the μ Topic Spotter and the other contributions is also presented. The empirical evidence includes specific statistical tests with MXit lingo, specific tests of the misspelling corrector, stemmer, and feedback mechanism, and an extensive exercise of content analysis with respect to mathematics topics.
- Full Text:
- Date Issued: 2012
Comparative biogeography and ecology of freshwater fishes in the Breede and associated river systems, South Africa
- Authors: Chakona, Albert
- Date: 2012
- Subjects: Freshwater fishes -- South Africa -- Breede River , Freshwater fishes -- South Africa -- Geographical distribution , Freshwater fishes -- Ecology , Feshwater fishes -- Genetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5372 , http://hdl.handle.net/10962/d1015694
- Description: Distribution patterns and levels of genetic diversity in extant taxa are a product of complex palaeogeographic processes and climatic oscillations as well as the species’ intrinsic ecological adaptations. The Cape Floristic Region of South Africa presents a unique system for studying the processes that promote species diversification and distribution patterns. This region has a high degree of endemism of both terrestrial and aquatic biota and is clearly isolated from neighbouring areas by the Cape Fold Mountains and the Great Escarpment. The objective of this study was to firstly examine the ecology of freshwater fishes belonging to the genera Galaxias, Pseudobarbus and Sandelia in the south-western CFR. This was followed by an assessment of the genetic diversity of these taxa. Unique lineages were identified and their distribution was mapped. The work aimed to explore the role of the region’s complex palaeogeographic and climatic history as well as the role of the species’ ecological adaptations in driving lineage diversification and shaping contemporary distribution patterns. The four main components of the study can be summarised as follows: 1. Habitat associations of three widely distributed lineages of Galaxias zebratus Pseudobarbus burchelli and Sandelia capensis were evaluated at multiple localities in minimally disturbed mountain tributaries of the Breede, Duiwenhoks and Goukou River systems. The lineages have distinct habitat associations which were related to differences in their morphological traits. The slender-bodied Galaxias ‘nebula’ and the fusiform-shaped Pseudobarbus ‘Breede’ are capable of exploiting upper reaches with faster water velocity. By contrast, the laterally compressed Sandelia ‘eastern’ is restricted to lower reaches, making this lineage more susceptible to a wide array of impacts. 2. A recently discovered lineage of Galaxias zebratus, (Galaxias ‘nebula’), was found to be capable of tolerating emersion for a prolonged period of time. This is the first time that such capabilities have been documented in an African galaxiid. These adaptations have implications for the interpretation of Galaxias ‘nebula’s wide distribution range. 3. The phylogeography of Galaxias ‘nebula’ across its entire distribution range was investigated using two mitochondrial genes (cytochrome c oxidase subunit I (COI) and cytochrome b (cyt b)). This lineage has a complex evolutionary history that was influenced by both intrinsic and extrinsic factors. Rare events such as episodic drainage connections during Pleistocene and Holocene pluvial periods, possibly augmented by river confluences during periods of lower sea-levels and river capture events seem to be the most credible explanation for the extensive contemporary distribution and the relatively shallow genetic divergence between different river systems. 4. Mitochondrial cyt b sequences were used (i) to assess genetic diversity in G. zebratus, P. burchelli and S. capensis from the south-western CFR and (ii) to determine the roles of intrinsic ecological adaptations and extrinsic landscape and climatic changes in promoting genetic diversification and shaping present day distribution patterns of lineages in the three taxa. Marine incursions during periods of major sea-level transgressions are proposed to have isolated populations in upland refugia, thereby driving allopatric divergence in these species. Subsequent connections of rivers during wetter periods and lower sea-levels are proposed to have facilitated post-speciation dispersal of lineages to attain present day distribution patterns. While detailed morphological studies and further genetic analysis are needed to substantiate the taxonomic status of the newly discovered lineages of Galaxias zebratus, Pseudobarbus burchelli and Sandelia capensis, results of the present study indicate that the south-western CFR represents a previously unrecognised centre of freshwater fish diversity and microendemism in the broader Cape Floristic Region. Accurate identification of lineages and comprehensive mapping of their distribution is a fundamental pre-requisite for ecological studies, assessing conservation status and implementation of appropriate conservation measures.
- Full Text:
- Date Issued: 2012
- Authors: Chakona, Albert
- Date: 2012
- Subjects: Freshwater fishes -- South Africa -- Breede River , Freshwater fishes -- South Africa -- Geographical distribution , Freshwater fishes -- Ecology , Feshwater fishes -- Genetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5372 , http://hdl.handle.net/10962/d1015694
- Description: Distribution patterns and levels of genetic diversity in extant taxa are a product of complex palaeogeographic processes and climatic oscillations as well as the species’ intrinsic ecological adaptations. The Cape Floristic Region of South Africa presents a unique system for studying the processes that promote species diversification and distribution patterns. This region has a high degree of endemism of both terrestrial and aquatic biota and is clearly isolated from neighbouring areas by the Cape Fold Mountains and the Great Escarpment. The objective of this study was to firstly examine the ecology of freshwater fishes belonging to the genera Galaxias, Pseudobarbus and Sandelia in the south-western CFR. This was followed by an assessment of the genetic diversity of these taxa. Unique lineages were identified and their distribution was mapped. The work aimed to explore the role of the region’s complex palaeogeographic and climatic history as well as the role of the species’ ecological adaptations in driving lineage diversification and shaping contemporary distribution patterns. The four main components of the study can be summarised as follows: 1. Habitat associations of three widely distributed lineages of Galaxias zebratus Pseudobarbus burchelli and Sandelia capensis were evaluated at multiple localities in minimally disturbed mountain tributaries of the Breede, Duiwenhoks and Goukou River systems. The lineages have distinct habitat associations which were related to differences in their morphological traits. The slender-bodied Galaxias ‘nebula’ and the fusiform-shaped Pseudobarbus ‘Breede’ are capable of exploiting upper reaches with faster water velocity. By contrast, the laterally compressed Sandelia ‘eastern’ is restricted to lower reaches, making this lineage more susceptible to a wide array of impacts. 2. A recently discovered lineage of Galaxias zebratus, (Galaxias ‘nebula’), was found to be capable of tolerating emersion for a prolonged period of time. This is the first time that such capabilities have been documented in an African galaxiid. These adaptations have implications for the interpretation of Galaxias ‘nebula’s wide distribution range. 3. The phylogeography of Galaxias ‘nebula’ across its entire distribution range was investigated using two mitochondrial genes (cytochrome c oxidase subunit I (COI) and cytochrome b (cyt b)). This lineage has a complex evolutionary history that was influenced by both intrinsic and extrinsic factors. Rare events such as episodic drainage connections during Pleistocene and Holocene pluvial periods, possibly augmented by river confluences during periods of lower sea-levels and river capture events seem to be the most credible explanation for the extensive contemporary distribution and the relatively shallow genetic divergence between different river systems. 4. Mitochondrial cyt b sequences were used (i) to assess genetic diversity in G. zebratus, P. burchelli and S. capensis from the south-western CFR and (ii) to determine the roles of intrinsic ecological adaptations and extrinsic landscape and climatic changes in promoting genetic diversification and shaping present day distribution patterns of lineages in the three taxa. Marine incursions during periods of major sea-level transgressions are proposed to have isolated populations in upland refugia, thereby driving allopatric divergence in these species. Subsequent connections of rivers during wetter periods and lower sea-levels are proposed to have facilitated post-speciation dispersal of lineages to attain present day distribution patterns. While detailed morphological studies and further genetic analysis are needed to substantiate the taxonomic status of the newly discovered lineages of Galaxias zebratus, Pseudobarbus burchelli and Sandelia capensis, results of the present study indicate that the south-western CFR represents a previously unrecognised centre of freshwater fish diversity and microendemism in the broader Cape Floristic Region. Accurate identification of lineages and comprehensive mapping of their distribution is a fundamental pre-requisite for ecological studies, assessing conservation status and implementation of appropriate conservation measures.
- Full Text:
- Date Issued: 2012
Systematic marine spatial planning and monitoring in a data poor environment: a case study of Algoa Bay, South Africa
- Authors: Chalmers, Russell
- Date: 2012
- Subjects: Spatial ecology -- South Africa -- Algoa Bay , Coastal zone management -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5373 , http://hdl.handle.net/10962/d1015695
- Description: Globally the failure of traditional fisheries management approaches is evident through the increasing number of overexploited or depleted marine stocks. Past sectoral management has failed to address cumulative impacts of fisheries activities on ecosystem health. Ecosystem based approaches have been advocated as a viable alternative for sustainable management of marine ecosystems as they present a holistic and precautionary approach, which integrates management of multiple activities with that of maintaining ecological health. Although conceptually advanced, implementation has been poor due to the complexities of competing ecological and socio-economic management objectives. Marine spatial planning can facilitate the implementation of ecosystem based management as it is able to address the spatial heterogeneity of biological communities and anthropogenic activities. Ecosystem based management approaches aim to address the full range of anthropogenic drivers on the marine environment, including but not limited to fisheries, tourism, coastal development, and land and marine based pollution sources amongst others. Fisheries activities have a direct impact on the local marine environment and were therefore the focus of this study which forms a starting point for implementing ecosystem based management in Algoa Bay. It is envisaged that future research will build on this foundation and include additional anthropogenic drivers into the management and monitoring strategies developed in this study in order to achieve a truly holistic ecosystem approach to management in Algoa Bay. Algoa Bay is situated centrally within the warm-temperate Agulhas bioregion along the east coast of South Africa and is the largest and best formed logarithmic spiral bay along this section of coastline. A large city, two commercial ports and several coastal settlements are located within Algoa Bay and a wide range of marine based activities occur within the area. A large section of the coastline is proclaimed as a National Park yet only two small offshore marine areas are formally protected. The development of a large marine protected area (MPA) adjoining the terrestrial section was proposed in the mid-1990s but a lack of adequate spatial data with which to quantify the fishery costs and conservation benefits led to wide scale public opposition and halted the declaration process. The primary goal of this study was to obtain and analyse baseline data to understand spatial and temporal trends in the distribution and abundance of fish populations and fisheries activities in order to develop a spatial framework for marine conservation and management in a data limited situation using Algoa Bay, South Africa as a case study. Furthermore, it aims to contribute to the development of a monitoring framework to evaluate the success of implementation and the resultant changes in biological and socio-economic environments. This information will be used to re-initiate the stakeholder engagement process in the future.
- Full Text:
- Date Issued: 2012
- Authors: Chalmers, Russell
- Date: 2012
- Subjects: Spatial ecology -- South Africa -- Algoa Bay , Coastal zone management -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5373 , http://hdl.handle.net/10962/d1015695
- Description: Globally the failure of traditional fisheries management approaches is evident through the increasing number of overexploited or depleted marine stocks. Past sectoral management has failed to address cumulative impacts of fisheries activities on ecosystem health. Ecosystem based approaches have been advocated as a viable alternative for sustainable management of marine ecosystems as they present a holistic and precautionary approach, which integrates management of multiple activities with that of maintaining ecological health. Although conceptually advanced, implementation has been poor due to the complexities of competing ecological and socio-economic management objectives. Marine spatial planning can facilitate the implementation of ecosystem based management as it is able to address the spatial heterogeneity of biological communities and anthropogenic activities. Ecosystem based management approaches aim to address the full range of anthropogenic drivers on the marine environment, including but not limited to fisheries, tourism, coastal development, and land and marine based pollution sources amongst others. Fisheries activities have a direct impact on the local marine environment and were therefore the focus of this study which forms a starting point for implementing ecosystem based management in Algoa Bay. It is envisaged that future research will build on this foundation and include additional anthropogenic drivers into the management and monitoring strategies developed in this study in order to achieve a truly holistic ecosystem approach to management in Algoa Bay. Algoa Bay is situated centrally within the warm-temperate Agulhas bioregion along the east coast of South Africa and is the largest and best formed logarithmic spiral bay along this section of coastline. A large city, two commercial ports and several coastal settlements are located within Algoa Bay and a wide range of marine based activities occur within the area. A large section of the coastline is proclaimed as a National Park yet only two small offshore marine areas are formally protected. The development of a large marine protected area (MPA) adjoining the terrestrial section was proposed in the mid-1990s but a lack of adequate spatial data with which to quantify the fishery costs and conservation benefits led to wide scale public opposition and halted the declaration process. The primary goal of this study was to obtain and analyse baseline data to understand spatial and temporal trends in the distribution and abundance of fish populations and fisheries activities in order to develop a spatial framework for marine conservation and management in a data limited situation using Algoa Bay, South Africa as a case study. Furthermore, it aims to contribute to the development of a monitoring framework to evaluate the success of implementation and the resultant changes in biological and socio-economic environments. This information will be used to re-initiate the stakeholder engagement process in the future.
- Full Text:
- Date Issued: 2012