Anthropogenic effects on sustainability of fish biodiversity in Tyume River, Eastern Cape, South Africa
- Authors: Kinya, Jane Njeri
- Date: 2018
- Subjects: Fishes--Behavior Fishes--Physiology Biotic communities
- Language: English
- Type: Thesis , Doctoral , Zoology
- Identifier: http://hdl.handle.net/10353/11740 , vital:39102
- Description: To determine the anthropogenic effects on the sustainability of fish biodiversity in Tyhume River, a mixture of ecological, economic and institutional parameters were used. To measure ecological parameters, 10 study sites were selected to represent varying intensities of anthropogenic effects on habitat, to represent typical river zones, and to correspond with historical survey sites for trend analysis. In these study sites, habitat characteristics that represent geomorphology (habitat quantity), water quality and ‘alien’ (non–native) fishes were used to determine anthropogenic effects on habitat and fish assemblage. The measured geomorphology characteristics included current velocity, wetted width and depth. The water quality characteristics used were temperature, pH and conductivity. To determine the effects of native and non-native on indigenous fish species in situ, electro fishing was used in riffles, small pools and runs; as well, in situ seine-netting was done in pools. The riches of river fish species was measured, using numbers abundance and longitudinal distribution indices. It was established that only 11percent of the Tyhume River habitat was relatively near natural, while 89percent exhibited anthropogenic habitat modification. Three major sources ofanthropogenic modification on habitat were identified. The major contributor of anthropogenic effects was Binfield Park Dam which accounted for 43percent of modification. The second source of anthropogenic effects on habitat was Alice urban area where storm water runoff accounted for 28percent of modification. Agricultural and livestock grazing, the third anthropogenic effect, accounted for 18percent of modification. The Eastern Cape Rocky, Sandelia bainsii Castelnau, 1861 and Border Barb, Barbus trevelyani Günther, 1868, exhibited reduced distribution. B. trevelyani longitudinal distribution was less than 25 km along the river continuum, with sporadic presence in the sandy foothills. S. bainsii was not found in the Lowland Zone, while previously this species extended from the mountainous zone to the confluence of the Tyhume and Keiskamma Rivers in the Lowland Zone. These indices supported the homogenization theory, as reflected by increased dissimilarity for two indigenous fish species, S. bainsii and B. trevelyani, among study sites. S. bainsii was previously distributed from source to confluence, while B. trevelyani recorded a 50percent decline at the study site below the Binfield Park Dam. To assign economic value to ecosystem services and assess post Rio-institutional parameters two hypothetical scenarios were developed from the ecological survey; one depicting current conditions and another depicting improved ecosystem services. Using a structured interview questionnaire, five ecosystem services in need of restoration were described to respondents. Applying the contingent valuation method respondents were asked a dichotomous choice question on willingness to pay (WTP). Results of the economic study from 209 personal interviews revealed, individuals were willing to pay an additional R 32.00 on their monthly water bill or R 384.00 annually. Generalizing this to 2 829 households living in the Alice and Ntselamanzi urban areas, a total value of R 1 086 336 would be realized annually. This was equivalent to the Nkonkobe Municipality annual budget for storm water management in Alice urban area. Costs/benefits revealed a positive net present value (NPV) = 1, which, in line with economic theory, meant gainers were able to compensate losers The institutional part of the economic survey sought to determine the effects of post Rio Earth Summit institutional measures on sustainable management of Tyhume River fish assemblage. A desk review of Rio Declaration and three South African statutes were used namely; Constitution Act 108 of 1996 (South African Constitution 1996); the National Environmental Management Biodiversity Act No. 10 of 2004 (NEMBA 2004), the National Environmental Management Act (NEMA) No. 107 of 1998 (NEMA 1998), and the National Water Act No. 36 of 1998 (NWA 1998). The Institutional and Analytic Development (IAD) Framework, coupled with requirements for sustainability of Multiple Use Resource Domains were used for the analysis. De Jure, the statutes had internationalization of environmental costs through “polluter pays principle”, while sustainable use was the overarching goal. De facto, the community participation, a requisite of post Rio measures, was low; however 89percent of community respondents were willing to join an environmental conservation group. This, coupled with the fact that 77percent of those interviewed supported the establishment of a Tyhume River Restoration Fund, provided scope for a broad based community participation framework This study contributes to sustainable use of Tyhume River and other lotic systems by generating information on the link between anthropogenic effects on fish biodiversity, economic value of ecosystems services and institutional mechanisms.
- Full Text:
- Date Issued: 2018
- Authors: Kinya, Jane Njeri
- Date: 2018
- Subjects: Fishes--Behavior Fishes--Physiology Biotic communities
- Language: English
- Type: Thesis , Doctoral , Zoology
- Identifier: http://hdl.handle.net/10353/11740 , vital:39102
- Description: To determine the anthropogenic effects on the sustainability of fish biodiversity in Tyhume River, a mixture of ecological, economic and institutional parameters were used. To measure ecological parameters, 10 study sites were selected to represent varying intensities of anthropogenic effects on habitat, to represent typical river zones, and to correspond with historical survey sites for trend analysis. In these study sites, habitat characteristics that represent geomorphology (habitat quantity), water quality and ‘alien’ (non–native) fishes were used to determine anthropogenic effects on habitat and fish assemblage. The measured geomorphology characteristics included current velocity, wetted width and depth. The water quality characteristics used were temperature, pH and conductivity. To determine the effects of native and non-native on indigenous fish species in situ, electro fishing was used in riffles, small pools and runs; as well, in situ seine-netting was done in pools. The riches of river fish species was measured, using numbers abundance and longitudinal distribution indices. It was established that only 11percent of the Tyhume River habitat was relatively near natural, while 89percent exhibited anthropogenic habitat modification. Three major sources ofanthropogenic modification on habitat were identified. The major contributor of anthropogenic effects was Binfield Park Dam which accounted for 43percent of modification. The second source of anthropogenic effects on habitat was Alice urban area where storm water runoff accounted for 28percent of modification. Agricultural and livestock grazing, the third anthropogenic effect, accounted for 18percent of modification. The Eastern Cape Rocky, Sandelia bainsii Castelnau, 1861 and Border Barb, Barbus trevelyani Günther, 1868, exhibited reduced distribution. B. trevelyani longitudinal distribution was less than 25 km along the river continuum, with sporadic presence in the sandy foothills. S. bainsii was not found in the Lowland Zone, while previously this species extended from the mountainous zone to the confluence of the Tyhume and Keiskamma Rivers in the Lowland Zone. These indices supported the homogenization theory, as reflected by increased dissimilarity for two indigenous fish species, S. bainsii and B. trevelyani, among study sites. S. bainsii was previously distributed from source to confluence, while B. trevelyani recorded a 50percent decline at the study site below the Binfield Park Dam. To assign economic value to ecosystem services and assess post Rio-institutional parameters two hypothetical scenarios were developed from the ecological survey; one depicting current conditions and another depicting improved ecosystem services. Using a structured interview questionnaire, five ecosystem services in need of restoration were described to respondents. Applying the contingent valuation method respondents were asked a dichotomous choice question on willingness to pay (WTP). Results of the economic study from 209 personal interviews revealed, individuals were willing to pay an additional R 32.00 on their monthly water bill or R 384.00 annually. Generalizing this to 2 829 households living in the Alice and Ntselamanzi urban areas, a total value of R 1 086 336 would be realized annually. This was equivalent to the Nkonkobe Municipality annual budget for storm water management in Alice urban area. Costs/benefits revealed a positive net present value (NPV) = 1, which, in line with economic theory, meant gainers were able to compensate losers The institutional part of the economic survey sought to determine the effects of post Rio Earth Summit institutional measures on sustainable management of Tyhume River fish assemblage. A desk review of Rio Declaration and three South African statutes were used namely; Constitution Act 108 of 1996 (South African Constitution 1996); the National Environmental Management Biodiversity Act No. 10 of 2004 (NEMBA 2004), the National Environmental Management Act (NEMA) No. 107 of 1998 (NEMA 1998), and the National Water Act No. 36 of 1998 (NWA 1998). The Institutional and Analytic Development (IAD) Framework, coupled with requirements for sustainability of Multiple Use Resource Domains were used for the analysis. De Jure, the statutes had internationalization of environmental costs through “polluter pays principle”, while sustainable use was the overarching goal. De facto, the community participation, a requisite of post Rio measures, was low; however 89percent of community respondents were willing to join an environmental conservation group. This, coupled with the fact that 77percent of those interviewed supported the establishment of a Tyhume River Restoration Fund, provided scope for a broad based community participation framework This study contributes to sustainable use of Tyhume River and other lotic systems by generating information on the link between anthropogenic effects on fish biodiversity, economic value of ecosystems services and institutional mechanisms.
- Full Text:
- Date Issued: 2018
Assessment of the Tyhume river health status using macroinvertebrates as indicators
- Authors: Fasi, Nokonwaba Nellineth
- Date: 2018
- Subjects: Invertebrates -- South Africa -- Eastern Cape Rivers -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Zoology
- Identifier: http://hdl.handle.net/10353/10861 , vital:35879
- Description: Ten sampling sites were selected along the Tyhume River corresponding to the upper, mid and lower reaches of the River. In total 48 families were collected during the study. The study observed different types of macroinvertebrate taxa; very low tolerant to pollution (e.g Heptageniidae; Notonemouridae; Perlidae), moderately pollution-tolerant (e.g. Caenidae; Chlorolestidae; Tricorythidae) and very tolerant of polluted conditions (e.g. Chironomidae; Muscidae; Oligochaetae). Both univariate and multivariate analyses were done using PRIMER V6. Above Confluence (ABCON, Site 10) had the highest number (37) of species while Mtloko (MTLOK, Site 2) had the lowest number (24) (Chi-square = 0.87; p < 0.05). The highest number of individuals (4023) was recorded at Macfairlane (MACFA, Site 5) while the lowest number (1240) at Honeydale (HONEY, Site 8) (Chi-square = 0.00; p < 0.05). Margalef’s index indicated Above Confluence (ABCON, Site 10; 4.762), had the highest values of species richness while Mtloko (MTLOK, Site 2; 3.227) had the lowest values (Chi-square = 1; p < 0.05). Pielou's evenness index indicated that Gqumashe (GQUMA, Site 7) had the highest values (0.7137), while Macfairlane (MACFA; Site 5) had the lowest (0.5109) (chi-square = 1; p < 0.05). Shannon-Wiener diversity indices, the highest diversity index values (2.573) of macroinvertebrates was recorded at Honeydale (HONEY, Site 8), and the lowest (1.684) at Macfairlane (MACFA, Site 5) (chi-square = 1; p < 0.05). The ASPT Scores did not differ significantly (P > 0.05) across sites. No significant difference was observed in the ASPT scores across the 10 sites (F = 0.75; df = 9.60; P > 0.05). Site 4 had the highest mean ASPT Scores with mean of 7.6), whereas the lowest. Three biotopes types, namely: stone, vegetation, gravel-sand-mud, stone and vegetation being the dominant biotopes at the 10 sites. The cluster analyses showed that macroinvertebrates were dependent on biotope preference while stone biotope showing greater macroinvertebrate densities. Euclidean distance of site classification with respect to physico-chemical parameters showed very low stress value (0.01) implying that physico-chemical parameters influenced species distribution within each sampling site. The results also showed that good health conditions existed at the most upstream sites than the lower reaches of the river, thus, indicating impacts of pollution within the river.
- Full Text:
- Date Issued: 2018
- Authors: Fasi, Nokonwaba Nellineth
- Date: 2018
- Subjects: Invertebrates -- South Africa -- Eastern Cape Rivers -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Zoology
- Identifier: http://hdl.handle.net/10353/10861 , vital:35879
- Description: Ten sampling sites were selected along the Tyhume River corresponding to the upper, mid and lower reaches of the River. In total 48 families were collected during the study. The study observed different types of macroinvertebrate taxa; very low tolerant to pollution (e.g Heptageniidae; Notonemouridae; Perlidae), moderately pollution-tolerant (e.g. Caenidae; Chlorolestidae; Tricorythidae) and very tolerant of polluted conditions (e.g. Chironomidae; Muscidae; Oligochaetae). Both univariate and multivariate analyses were done using PRIMER V6. Above Confluence (ABCON, Site 10) had the highest number (37) of species while Mtloko (MTLOK, Site 2) had the lowest number (24) (Chi-square = 0.87; p < 0.05). The highest number of individuals (4023) was recorded at Macfairlane (MACFA, Site 5) while the lowest number (1240) at Honeydale (HONEY, Site 8) (Chi-square = 0.00; p < 0.05). Margalef’s index indicated Above Confluence (ABCON, Site 10; 4.762), had the highest values of species richness while Mtloko (MTLOK, Site 2; 3.227) had the lowest values (Chi-square = 1; p < 0.05). Pielou's evenness index indicated that Gqumashe (GQUMA, Site 7) had the highest values (0.7137), while Macfairlane (MACFA; Site 5) had the lowest (0.5109) (chi-square = 1; p < 0.05). Shannon-Wiener diversity indices, the highest diversity index values (2.573) of macroinvertebrates was recorded at Honeydale (HONEY, Site 8), and the lowest (1.684) at Macfairlane (MACFA, Site 5) (chi-square = 1; p < 0.05). The ASPT Scores did not differ significantly (P > 0.05) across sites. No significant difference was observed in the ASPT scores across the 10 sites (F = 0.75; df = 9.60; P > 0.05). Site 4 had the highest mean ASPT Scores with mean of 7.6), whereas the lowest. Three biotopes types, namely: stone, vegetation, gravel-sand-mud, stone and vegetation being the dominant biotopes at the 10 sites. The cluster analyses showed that macroinvertebrates were dependent on biotope preference while stone biotope showing greater macroinvertebrate densities. Euclidean distance of site classification with respect to physico-chemical parameters showed very low stress value (0.01) implying that physico-chemical parameters influenced species distribution within each sampling site. The results also showed that good health conditions existed at the most upstream sites than the lower reaches of the river, thus, indicating impacts of pollution within the river.
- Full Text:
- Date Issued: 2018
Population, communication and habitat comparisons between the major gummivorous strepsirhines of Madagascar (phaner) and Cameroon (euoticus)
- Authors: Forbanka, Derick Nomuh
- Date: 2016
- Subjects: Adaptation (Biology) , Mammals -- Evolution , Mammals -- Behavior
- Language: English
- Type: Thesis , Doctoral , Zoology
- Identifier: http://hdl.handle.net/10353/15957 , vital:40567
- Description: The suborder Strepsirhini contains a large proportion of the living gummivorous mammal taxa, and includes two genera of specialist gummivores, Euoticus and Phaner, which present particularly interesting cases of convergent adaptive evolution in Africa and Madagascar, respectively. Although these genera are not closely related, they share several anatomical, behavioural and physiological specialisations associated with their diets, and despite their biogeographical separation, there seems to be substantial coincidence in their habitats and habits. Neither the ecology nor the systematics of Phaner and Euoticus has been the subject of much detailed research, and little is known of the conservation status of the genera. Even their specific diversity is unresolved. In this study I investigated and compared aspects of their ecology at both a macro-and a microhabitat scale, including wild populations of all groups within the two genera that have been accorded species status in recent field guides and systematic reviews. I also studied aspects of their social communication behaviour as clues to their species-level diversity. Species and their formation (or speciation) have inspired a great deal of evolutionary research, but remain contentious issues in evolutionary biology. This is due both to the difficulties inherent in inferring the details of a dynamic biological process that occurred over some time in the past from the recent, relatively static patterns of variation observed, as well as the limited consensus among biologists in identifying such patterns. It is therefore important to distinguish the kinds of patterns in nature that are predicted by different views of species and speciation, and also to see how well these predictions fare when applied to the speciation patterns found in strepsirhine primates. Theories of speciation cannot be separated from species concepts, and one concept widely supported in primatology is the Recognition Concept of species because of its heuristic nature. The Recognition Concept is based on Specific-mate Recognition Systems (SMRS). I focussed on SMRS features of Euoticus and Phaner, loud call specificity, and species’ preferred habitats. My results provided some support for the distinctiveness of currently identified species, although this was not clear-cut. Population densities of both Phaner and Euoticus appear to have declined in recent years, even though both Phaner and Euoticus appear to be well adapted to both primary and secondary forest, and exhibit ecological plasticity. Statistically some loud call parameters vary among the putative species of the genus Phaner and not Euoticus. Phaner pallescens at Kirindy, Madasgascar was clearly able to discriminate loud calls of its own population from other proposed species within the genus. Most loud call parameters did not show any statistical degradation with increasing distance. A crucial finding of my study was that the two lineages are not only convergent in terms of dietary and locomotor aspects of their ecology, but also in the structures of their loud calls. The environmental adaptation of communication systems is often overlooked when studying adaptive convergence, but my study indicates that acoustic properties are a crucial aspect of a species’ preferred habitat. The results of this study can be used to improve conservation planning, and also add to our understanding of the evolutionary history of strepsirhine primates.
- Full Text:
- Date Issued: 2016
- Authors: Forbanka, Derick Nomuh
- Date: 2016
- Subjects: Adaptation (Biology) , Mammals -- Evolution , Mammals -- Behavior
- Language: English
- Type: Thesis , Doctoral , Zoology
- Identifier: http://hdl.handle.net/10353/15957 , vital:40567
- Description: The suborder Strepsirhini contains a large proportion of the living gummivorous mammal taxa, and includes two genera of specialist gummivores, Euoticus and Phaner, which present particularly interesting cases of convergent adaptive evolution in Africa and Madagascar, respectively. Although these genera are not closely related, they share several anatomical, behavioural and physiological specialisations associated with their diets, and despite their biogeographical separation, there seems to be substantial coincidence in their habitats and habits. Neither the ecology nor the systematics of Phaner and Euoticus has been the subject of much detailed research, and little is known of the conservation status of the genera. Even their specific diversity is unresolved. In this study I investigated and compared aspects of their ecology at both a macro-and a microhabitat scale, including wild populations of all groups within the two genera that have been accorded species status in recent field guides and systematic reviews. I also studied aspects of their social communication behaviour as clues to their species-level diversity. Species and their formation (or speciation) have inspired a great deal of evolutionary research, but remain contentious issues in evolutionary biology. This is due both to the difficulties inherent in inferring the details of a dynamic biological process that occurred over some time in the past from the recent, relatively static patterns of variation observed, as well as the limited consensus among biologists in identifying such patterns. It is therefore important to distinguish the kinds of patterns in nature that are predicted by different views of species and speciation, and also to see how well these predictions fare when applied to the speciation patterns found in strepsirhine primates. Theories of speciation cannot be separated from species concepts, and one concept widely supported in primatology is the Recognition Concept of species because of its heuristic nature. The Recognition Concept is based on Specific-mate Recognition Systems (SMRS). I focussed on SMRS features of Euoticus and Phaner, loud call specificity, and species’ preferred habitats. My results provided some support for the distinctiveness of currently identified species, although this was not clear-cut. Population densities of both Phaner and Euoticus appear to have declined in recent years, even though both Phaner and Euoticus appear to be well adapted to both primary and secondary forest, and exhibit ecological plasticity. Statistically some loud call parameters vary among the putative species of the genus Phaner and not Euoticus. Phaner pallescens at Kirindy, Madasgascar was clearly able to discriminate loud calls of its own population from other proposed species within the genus. Most loud call parameters did not show any statistical degradation with increasing distance. A crucial finding of my study was that the two lineages are not only convergent in terms of dietary and locomotor aspects of their ecology, but also in the structures of their loud calls. The environmental adaptation of communication systems is often overlooked when studying adaptive convergence, but my study indicates that acoustic properties are a crucial aspect of a species’ preferred habitat. The results of this study can be used to improve conservation planning, and also add to our understanding of the evolutionary history of strepsirhine primates.
- Full Text:
- Date Issued: 2016
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