Prioritising native fish populations for conservation using genetics in the Groot Marico catchment, North West Province, South Africa
- Authors: Van der Walt, Kerry-Ann
- Date: 2014
- Subjects: Native fishes Fishery management -- South Africa -- North West Fish populations Fishes -- Conservation -- South Africa -- Western Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/69102 , vital:29390
- Description: The Groot Marico catchment in the North West Province is a National Freshwater Ecosystem Priority Area (NFEPA) because it represents unique landscape features with unique biodiversity that are considered to be of special ecological significance. Three native freshwater species Amphilius uranoscopus, Chiloglanis pretoriae and Barbus motebensis, have high local conservation importance and B. motebensis is endemic to the catchment and is IUCN-listed as vulnerable. The main objective of this study is to contribute towards the effective conservation of these three species in the Groot Marico River system by assessing their genetic structure to determine whether tributary populations of the three species comprise of one genetic population or whether they are divided into genetically distinct subpopulations, in order to prioritise areas for conservation. The central null hypothesis was that there is no genetic differentiation between tributary populations (i.e., panmixia) of B. motebensis, A. uranoscopus and C. pretoriae in the Groot Marico catchment, North West Province. In total, 80 individuals per species were collected, targeting at least 10 individuals per population from a total of eight populations (seven tributaries and the Groot Marico main stem) and across the study area. Samples were collected by electrofishing and specimens were euthanized using an overdose of clove oil. A sample of muscle tissue was removed for genetic evaluation and the remainder of the specimens served as voucher specimens. For the genetic evaluation, mitochondrial (ND2, cyt b) and nuclear (S7) genes were used. Genetic techniques used were DNA extraction, polymerase chain reaction (PCR), purification and sequencing. From the 240 individuals collected, 123 sequences for B. motebensis, 111 sequences for A. uranoscopus and 103 sequences for C. pretoriae were analysed across all three genes. Statistical analysis included looking at cleaned sequences in order to obtain models using MODELTEST (version 3.06). Population structuring and phylogeographic analysis was performed in Arlequin (version 2000), TCS (version 1.2.1) and PAUP*. Results indicated that for B. motebensis the null hypothesis could be rejected as there were two distinct lineages (the Draai and Eastern lineages) that demonstrated significant divergence in both the ND2 and S7 genes, suggesting historical isolation. The low divergence in the mitochondrial cytochrome b gene (0% < D < 0.8%) suggests that this isolation is not very old and is probably not comparable to species level differentiation. The null hypothesis was also rejected for A. uranoscopus as there were also significant levels of differentiation between tributary populations resulting in the identification of two lineages (the Ribbok and Western lineages). However, for C. pretoriae, the null hypothesis could not be rejected as there was no genetic differentiation between tributary populations i.e., one panmictic population. Therefore, due to each species showing different genetic structuring within the tributary populations, more than one priority area for conservation needs to be implemented. These priority areas of conservation where therefore evaluated based on the current conservation status of the species (B. motebensis being vulnerable on the IUCN Red List), the number of Evolutionary Significant Units for each species and the overall genetic diversity of all three species in the Groot Marico catchment. In total, four tributary populations were conservation priorities areas, these were the Draai, Vanstraatens, Ribbok and Kaaloog tributaries. The Draai, Vanstraatens and Kaaloog tributaries were selected as priority areas for B. motebensis (B. motebensis is considered to be the most vulnerable of all three species). The Draai tributary was selected due to the B. motebensis population within the tributary showing isolation from the rest of the tributary populations. In order to conserve B. motebensis from the Southern lineage, the Vanstraatens and Kaaloog tributaries were selected. Reasons for selecting these two specific tributaries within the Southern lineage were that the Vanstraatens tributary had unique alleles (three Evolutionary Significant Units) for B. motebensis and the Kaaloog tributary had high genetic diversity (HD = 0.889, ND2 gene) when compared to the other tributary populations. The Ribbok and Vanstraatens tributaries were selected as priority areas for the conservation of A. uranoscopus. The Ribbok tributary was selected as it showed isolation from the rest of the tributary populations, as seen with the Draai tributary (B. motebensis) and the Vanstraatens tributary was selected to represent the Western lineage as it had the highest diversity for both genes (ND2 and S7). The Ribbok tributary has the highest prioritisation when compared to the Vanstraatens tributary. Chiloglanis pretoriae occurs within the Draai, Vanstraatens, Ribbok and Kaaloog tributaries, therefore by prioritising these tributaries for conservation, C. pretoriae will in turn be conserved.
- Full Text:
- Date Issued: 2014
- Authors: Van der Walt, Kerry-Ann
- Date: 2014
- Subjects: Native fishes Fishery management -- South Africa -- North West Fish populations Fishes -- Conservation -- South Africa -- Western Cape
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/69102 , vital:29390
- Description: The Groot Marico catchment in the North West Province is a National Freshwater Ecosystem Priority Area (NFEPA) because it represents unique landscape features with unique biodiversity that are considered to be of special ecological significance. Three native freshwater species Amphilius uranoscopus, Chiloglanis pretoriae and Barbus motebensis, have high local conservation importance and B. motebensis is endemic to the catchment and is IUCN-listed as vulnerable. The main objective of this study is to contribute towards the effective conservation of these three species in the Groot Marico River system by assessing their genetic structure to determine whether tributary populations of the three species comprise of one genetic population or whether they are divided into genetically distinct subpopulations, in order to prioritise areas for conservation. The central null hypothesis was that there is no genetic differentiation between tributary populations (i.e., panmixia) of B. motebensis, A. uranoscopus and C. pretoriae in the Groot Marico catchment, North West Province. In total, 80 individuals per species were collected, targeting at least 10 individuals per population from a total of eight populations (seven tributaries and the Groot Marico main stem) and across the study area. Samples were collected by electrofishing and specimens were euthanized using an overdose of clove oil. A sample of muscle tissue was removed for genetic evaluation and the remainder of the specimens served as voucher specimens. For the genetic evaluation, mitochondrial (ND2, cyt b) and nuclear (S7) genes were used. Genetic techniques used were DNA extraction, polymerase chain reaction (PCR), purification and sequencing. From the 240 individuals collected, 123 sequences for B. motebensis, 111 sequences for A. uranoscopus and 103 sequences for C. pretoriae were analysed across all three genes. Statistical analysis included looking at cleaned sequences in order to obtain models using MODELTEST (version 3.06). Population structuring and phylogeographic analysis was performed in Arlequin (version 2000), TCS (version 1.2.1) and PAUP*. Results indicated that for B. motebensis the null hypothesis could be rejected as there were two distinct lineages (the Draai and Eastern lineages) that demonstrated significant divergence in both the ND2 and S7 genes, suggesting historical isolation. The low divergence in the mitochondrial cytochrome b gene (0% < D < 0.8%) suggests that this isolation is not very old and is probably not comparable to species level differentiation. The null hypothesis was also rejected for A. uranoscopus as there were also significant levels of differentiation between tributary populations resulting in the identification of two lineages (the Ribbok and Western lineages). However, for C. pretoriae, the null hypothesis could not be rejected as there was no genetic differentiation between tributary populations i.e., one panmictic population. Therefore, due to each species showing different genetic structuring within the tributary populations, more than one priority area for conservation needs to be implemented. These priority areas of conservation where therefore evaluated based on the current conservation status of the species (B. motebensis being vulnerable on the IUCN Red List), the number of Evolutionary Significant Units for each species and the overall genetic diversity of all three species in the Groot Marico catchment. In total, four tributary populations were conservation priorities areas, these were the Draai, Vanstraatens, Ribbok and Kaaloog tributaries. The Draai, Vanstraatens and Kaaloog tributaries were selected as priority areas for B. motebensis (B. motebensis is considered to be the most vulnerable of all three species). The Draai tributary was selected due to the B. motebensis population within the tributary showing isolation from the rest of the tributary populations. In order to conserve B. motebensis from the Southern lineage, the Vanstraatens and Kaaloog tributaries were selected. Reasons for selecting these two specific tributaries within the Southern lineage were that the Vanstraatens tributary had unique alleles (three Evolutionary Significant Units) for B. motebensis and the Kaaloog tributary had high genetic diversity (HD = 0.889, ND2 gene) when compared to the other tributary populations. The Ribbok and Vanstraatens tributaries were selected as priority areas for the conservation of A. uranoscopus. The Ribbok tributary was selected as it showed isolation from the rest of the tributary populations, as seen with the Draai tributary (B. motebensis) and the Vanstraatens tributary was selected to represent the Western lineage as it had the highest diversity for both genes (ND2 and S7). The Ribbok tributary has the highest prioritisation when compared to the Vanstraatens tributary. Chiloglanis pretoriae occurs within the Draai, Vanstraatens, Ribbok and Kaaloog tributaries, therefore by prioritising these tributaries for conservation, C. pretoriae will in turn be conserved.
- Full Text:
- Date Issued: 2014
Exploring the influence of spirituality on students' well-being
- Authors: Magula, Nokuzola Princess
- Date: 2013
- Subjects: Sprituality , Well-being , Students , Christians , Rhodes University , College students -- Religious life -- South Africa -- Eastern Cape , Christian college students -- Religious life -- South Africa -- Eastern Cape , Universities and colleges -- Religion -- Research , Well-being -- Religious aspects , Spirituality -- Research
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2918 , http://hdl.handle.net/10962/d1002083
- Description: This study was aimed at exploring the impact of spirituality on the well-being of students at Rhodes University in South Africa. The study was conducted within a qualitative research paradigm deploying an interpretive phenomenological analysis strategy for data analysis. The study involved a sample of four female Honours students who were all active Christians. The selected students were interviewed to elicit their experiences of spirituality and how this related to their everyday lives. The study used semi-structured interviews in order to get as much information as possible from the small sample of research participants. Data generated in this study was processed, presented and interpreted inductively and hermeneutically in order to identify emerging superordinate themes. This study found that spirituality was experienced as having a positive impact on well-being by all the four students. The study revealed that belief and faith in God amongst the students resulted in enhanced and positive experiences of hope, optimism and compassion which provided the students with a deeper sense of meaning of life and a source of direction in difficult times. The study further showed that participants experienced spirituality as a regulatory mechanism shaping their lifestyles and behaviours. Participants viewed their spirituality and religiosity as a source of social support helping them to cope with distressful situations. The findings of this study are consistent with the findings of previous studies done in the field of psychology and spirituality. The fact that this study has shown that spirituality and religion has a positive impact on student’s well-being may mean that University administrators and psychologists may find the study interesting and valuable
- Full Text:
- Date Issued: 2013
- Authors: Magula, Nokuzola Princess
- Date: 2013
- Subjects: Sprituality , Well-being , Students , Christians , Rhodes University , College students -- Religious life -- South Africa -- Eastern Cape , Christian college students -- Religious life -- South Africa -- Eastern Cape , Universities and colleges -- Religion -- Research , Well-being -- Religious aspects , Spirituality -- Research
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2918 , http://hdl.handle.net/10962/d1002083
- Description: This study was aimed at exploring the impact of spirituality on the well-being of students at Rhodes University in South Africa. The study was conducted within a qualitative research paradigm deploying an interpretive phenomenological analysis strategy for data analysis. The study involved a sample of four female Honours students who were all active Christians. The selected students were interviewed to elicit their experiences of spirituality and how this related to their everyday lives. The study used semi-structured interviews in order to get as much information as possible from the small sample of research participants. Data generated in this study was processed, presented and interpreted inductively and hermeneutically in order to identify emerging superordinate themes. This study found that spirituality was experienced as having a positive impact on well-being by all the four students. The study revealed that belief and faith in God amongst the students resulted in enhanced and positive experiences of hope, optimism and compassion which provided the students with a deeper sense of meaning of life and a source of direction in difficult times. The study further showed that participants experienced spirituality as a regulatory mechanism shaping their lifestyles and behaviours. Participants viewed their spirituality and religiosity as a source of social support helping them to cope with distressful situations. The findings of this study are consistent with the findings of previous studies done in the field of psychology and spirituality. The fact that this study has shown that spirituality and religion has a positive impact on student’s well-being may mean that University administrators and psychologists may find the study interesting and valuable
- Full Text:
- Date Issued: 2013
Revolutionary Overthrow of Constitutional Orders in Africa
- Authors: Anyangwe, Carlson
- Date: 2010
- Subjects: Constitutional law -- Africa Civil-military relations Coups’d’états Revolutions
- Language: English
- Type: text , Lectures
- Identifier: http://hdl.handle.net/11260/823 , vital:29828
- Description: The title of my Professorial Inaugural Lecture is ‘Revolutionary Overthrow of Constitutional Orders in Africa’. It is a subject at the intersection of three disciplines: jurisprudence and legal philosophy, constitutional law and power politics, and civil-military relations, i.e. military security policy which is one aspect of national security policy.2 The subject is of interest in at least four aspects: (i) it problematises the inescapable question of governance in the African continent; (ii) it challenges the democratization agenda in Africa - how does one democratize not only political governance but also the instruments of violence in the state? (iii) it challenges African constitutional lawyers and policy makers to seek a constitutional model that addresses the enduring menace of the power of the gun in African affairs and the changing role of the military in African politics; and (iv) it underscores national security and sovereignty concerns.
- Full Text:
- Date Issued: 2010
- Authors: Anyangwe, Carlson
- Date: 2010
- Subjects: Constitutional law -- Africa Civil-military relations Coups’d’états Revolutions
- Language: English
- Type: text , Lectures
- Identifier: http://hdl.handle.net/11260/823 , vital:29828
- Description: The title of my Professorial Inaugural Lecture is ‘Revolutionary Overthrow of Constitutional Orders in Africa’. It is a subject at the intersection of three disciplines: jurisprudence and legal philosophy, constitutional law and power politics, and civil-military relations, i.e. military security policy which is one aspect of national security policy.2 The subject is of interest in at least four aspects: (i) it problematises the inescapable question of governance in the African continent; (ii) it challenges the democratization agenda in Africa - how does one democratize not only political governance but also the instruments of violence in the state? (iii) it challenges African constitutional lawyers and policy makers to seek a constitutional model that addresses the enduring menace of the power of the gun in African affairs and the changing role of the military in African politics; and (iv) it underscores national security and sovereignty concerns.
- Full Text:
- Date Issued: 2010
- «
- ‹
- 1
- ›
- »