Effect of water temperature on the biogeography of South African estuarine fishes associated with the subtropical/warm temperate subtraction zone
- Maree, R C, Booth, Anthony J, Whitfield, A K
- Authors: Maree, R C , Booth, Anthony J , Whitfield, A K
- Date: 2000
- Language: English
- Type: text , Article
- Identifier: vital:7133 , http://hdl.handle.net/10962/d1011776
- Description: Estuarine biogeographical regions along the southeastern coast of South Africa were investigated in terms of fish distribution and abundance patterns, with particular emphasis on the role of water temperature in influencing these patterns. Qualitative and quantitative analyses were conducted upon the ichthyofaunal assemblages to determine whether the location of the subtropical/warm temperate boundary corresponds to that proposed by Whitfield.(n1) Analyses included the distribution ranges of species associated with estuaries according to presence/absence data, cluster analysis of gill net catches in eight estuaries along the southeastern coast and the relative proportion of tropical to temperate marine species within these eight systems. Quantitative analysis indicated that the ichthyofaunal biogeographical regions are indeed a reflection of water temperature regimes and that the subtropical/warm temperate boundary is located between the Great Kei and Mbashe estuaries. A strong negative correlation was found between the number of temperate fish species and the mean of the minimum monthly temperatures recorded in the systems studied. Qualitative analysis revealed that a barrier appears to exist in the vicinity of the Swartkops estuary, which prevents the westward migration of tropical 'vagrants'. The influence of the Agulhas Current along the east coast and its divergence from the coastline in the Algoa Bay region, as well as upwelling phenomena on the southeast and south coasts are identified as major factors that influence marine and estuarine temperature regimes and therefore the ichythyofauna of this region.
- Full Text: false
- Date Issued: 2000
- Authors: Maree, R C , Booth, Anthony J , Whitfield, A K
- Date: 2000
- Language: English
- Type: text , Article
- Identifier: vital:7133 , http://hdl.handle.net/10962/d1011776
- Description: Estuarine biogeographical regions along the southeastern coast of South Africa were investigated in terms of fish distribution and abundance patterns, with particular emphasis on the role of water temperature in influencing these patterns. Qualitative and quantitative analyses were conducted upon the ichthyofaunal assemblages to determine whether the location of the subtropical/warm temperate boundary corresponds to that proposed by Whitfield.(n1) Analyses included the distribution ranges of species associated with estuaries according to presence/absence data, cluster analysis of gill net catches in eight estuaries along the southeastern coast and the relative proportion of tropical to temperate marine species within these eight systems. Quantitative analysis indicated that the ichthyofaunal biogeographical regions are indeed a reflection of water temperature regimes and that the subtropical/warm temperate boundary is located between the Great Kei and Mbashe estuaries. A strong negative correlation was found between the number of temperate fish species and the mean of the minimum monthly temperatures recorded in the systems studied. Qualitative analysis revealed that a barrier appears to exist in the vicinity of the Swartkops estuary, which prevents the westward migration of tropical 'vagrants'. The influence of the Agulhas Current along the east coast and its divergence from the coastline in the Algoa Bay region, as well as upwelling phenomena on the southeast and south coasts are identified as major factors that influence marine and estuarine temperature regimes and therefore the ichythyofauna of this region.
- Full Text: false
- Date Issued: 2000
Effect of water temperature on the biogeography of South African estuarine fishes associated with the subtropical/warm temperate subtraction zone
- Maree, R C, Booth, Anthony J, Whitfield, A K
- Authors: Maree, R C , Booth, Anthony J , Whitfield, A K
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:6766 , http://hdl.handle.net/10962/d1008043
- Description: Estuarine biogeographical regions along the southeastern coast of South Africa were investigated in terms of fish distribution and abundance patterns, with particular emphasis on the role of water temperature in influencing these patterns. Qualitative and quantitative analyses were conducted upon the ichthyofaunal assemblages to determine whether the location of the subtropical/warm temperate boundary corresponds to that proposed by Whitfield.(n1) Analyses included the distribution ranges of species associated with estuaries according to presence/absence data, cluster analysis of gill net catches in eight estuaries along the southeastern coast and the relative proportion of tropical to temperate marine species within these eight systems. Quantitative analysis indicated that the ichthyofaunal biogeographical regions are indeed a reflection of water temperature regimes and that the subtropical/warm temperate boundary is located between the Great Kei and Mbashe estuaries. A strong negative correlation was found between the number of temperate fish species and the mean of the minimum monthly temperatures recorded in the systems studied. Qualitative analysis revealed that a barrier appears to exist in the vicinity of the Swartkops estuary, which prevents the westward migration of tropical 'vagrants'. The influence of the Agulhas Current along the east coast and its divergence from the coastline in the Algoa Bay region, as well as upwelling phenomena on the southeast and south coasts are identified as major factors that influence marine and estuarine temperature regimes and therefore the ichythyofauna of this region.
- Full Text: false
- Date Issued: 2000
- Authors: Maree, R C , Booth, Anthony J , Whitfield, A K
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:6766 , http://hdl.handle.net/10962/d1008043
- Description: Estuarine biogeographical regions along the southeastern coast of South Africa were investigated in terms of fish distribution and abundance patterns, with particular emphasis on the role of water temperature in influencing these patterns. Qualitative and quantitative analyses were conducted upon the ichthyofaunal assemblages to determine whether the location of the subtropical/warm temperate boundary corresponds to that proposed by Whitfield.(n1) Analyses included the distribution ranges of species associated with estuaries according to presence/absence data, cluster analysis of gill net catches in eight estuaries along the southeastern coast and the relative proportion of tropical to temperate marine species within these eight systems. Quantitative analysis indicated that the ichthyofaunal biogeographical regions are indeed a reflection of water temperature regimes and that the subtropical/warm temperate boundary is located between the Great Kei and Mbashe estuaries. A strong negative correlation was found between the number of temperate fish species and the mean of the minimum monthly temperatures recorded in the systems studied. Qualitative analysis revealed that a barrier appears to exist in the vicinity of the Swartkops estuary, which prevents the westward migration of tropical 'vagrants'. The influence of the Agulhas Current along the east coast and its divergence from the coastline in the Algoa Bay region, as well as upwelling phenomena on the southeast and south coasts are identified as major factors that influence marine and estuarine temperature regimes and therefore the ichythyofauna of this region.
- Full Text: false
- Date Issued: 2000
Palynology and palaeo-environment of Pleistocene hyaena coprolites from an open-air site at Oyster Bay, Eastern Cape coast, South Africa
- Carrion, J S, Brink, J S, Scott, Lucy E P, Binneman, J N F
- Authors: Carrion, J S , Brink, J S , Scott, Lucy E P , Binneman, J N F
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:7000 , http://hdl.handle.net/10962/d1008357
- Description: Hyaena coprolites in a soil horizon at Oyster Bay, Eastern Cape coast, South Africa, were found associated with abundant, early Last Glacial vertebrate faunal remains that were apparently accumulated by brown hyaenas and prehistoric humans. Artefacts of the Howieson's Poort sub-stage of the Middle Stone Age occur in the same soil. Although direct association between the different finds cannot be demonstrated, there is evidence to suggest that they are broadly contemporaneous. Pollen assemblages in the coprolites were dominated by Myrica and, to a lesser extent, Stoebe-Elytropappus type and Poaceae. Comparison with the modern pollen spectrum suggests that the past environment differed markedly from the current. The presence of Stoebe-Elytropappus, in particular, is considered to indicate a displacement of vegetation zones to lower altitudes. Both fossil pollen and fauna suggest a landscape with a complex mosaic of vegetation indicative of overall cooler, more inland conditions than today.
- Full Text: false
- Date Issued: 2000
- Authors: Carrion, J S , Brink, J S , Scott, Lucy E P , Binneman, J N F
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:7000 , http://hdl.handle.net/10962/d1008357
- Description: Hyaena coprolites in a soil horizon at Oyster Bay, Eastern Cape coast, South Africa, were found associated with abundant, early Last Glacial vertebrate faunal remains that were apparently accumulated by brown hyaenas and prehistoric humans. Artefacts of the Howieson's Poort sub-stage of the Middle Stone Age occur in the same soil. Although direct association between the different finds cannot be demonstrated, there is evidence to suggest that they are broadly contemporaneous. Pollen assemblages in the coprolites were dominated by Myrica and, to a lesser extent, Stoebe-Elytropappus type and Poaceae. Comparison with the modern pollen spectrum suggests that the past environment differed markedly from the current. The presence of Stoebe-Elytropappus, in particular, is considered to indicate a displacement of vegetation zones to lower altitudes. Both fossil pollen and fauna suggest a landscape with a complex mosaic of vegetation indicative of overall cooler, more inland conditions than today.
- Full Text: false
- Date Issued: 2000
Replication of maximal work output levels in able-bodied workers and candidates for disability assessments: benchmark data and guidelines
- Charteris, J, James, Jonathan P
- Authors: Charteris, J , James, Jonathan P
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:6752 , http://hdl.handle.net/10962/d1009332
- Description: [From the introduction]: Injured-at-work employees, when the impairments are musculo-skeletal, and the injury beyond dispute, may be faced with formal rehabilitation or informal recuperation, sometimes preceded by surgical intervention, or they may be exposed to a process of application for compensation, part of which may involve medico-legal assessments. Questions that need to be addressed somewhere in this process will determine whether the impairment is of short duration, chronic or irreparable, and will involve determination also of the severity of the impairment and the issue of the workers’ capacity to return to the former occupation versus the need to find a new employment niche commensurate with the disabled workers’ capabilities. Inevitably in this process, if it is formal, someone will need to assess the musculoskeletal strength of the injured employee and make pronouncements as to physical capacity and work-readiness. In the absence of clinical ergonomists in South Africa this task falls to a variety of professionals, some well and others poorly trained to make these determinations. Most often the assessments of work-readiness are crude, amounting to little more than unsubstantiable value judgements of supervisors or health professionals not well versed in human performance capabilities. Increasingly however, better qualified professionals are making themselves available to meet the growing demands of a more employee-centred working ethos in this country. This paper is targeted at those medical, paramedical and ergonomics professionals who already have the facilities and the expertise to make use of the technique outlined herein, to further enhance their already sound means of job-related disability assessment.
- Full Text:
- Date Issued: 2000
- Authors: Charteris, J , James, Jonathan P
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:6752 , http://hdl.handle.net/10962/d1009332
- Description: [From the introduction]: Injured-at-work employees, when the impairments are musculo-skeletal, and the injury beyond dispute, may be faced with formal rehabilitation or informal recuperation, sometimes preceded by surgical intervention, or they may be exposed to a process of application for compensation, part of which may involve medico-legal assessments. Questions that need to be addressed somewhere in this process will determine whether the impairment is of short duration, chronic or irreparable, and will involve determination also of the severity of the impairment and the issue of the workers’ capacity to return to the former occupation versus the need to find a new employment niche commensurate with the disabled workers’ capabilities. Inevitably in this process, if it is formal, someone will need to assess the musculoskeletal strength of the injured employee and make pronouncements as to physical capacity and work-readiness. In the absence of clinical ergonomists in South Africa this task falls to a variety of professionals, some well and others poorly trained to make these determinations. Most often the assessments of work-readiness are crude, amounting to little more than unsubstantiable value judgements of supervisors or health professionals not well versed in human performance capabilities. Increasingly however, better qualified professionals are making themselves available to meet the growing demands of a more employee-centred working ethos in this country. This paper is targeted at those medical, paramedical and ergonomics professionals who already have the facilities and the expertise to make use of the technique outlined herein, to further enhance their already sound means of job-related disability assessment.
- Full Text:
- Date Issued: 2000
Topical Opinion - Organising on the mines
- SAIRR
- Authors: SAIRR
- Date: 2000
- Subjects: SAIRR
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/111247 , vital:33420
- Description: When the National Union of Mineworkers was formed an experienced unionist said to me "organising workers in South Africa is the art of the possible". But organising workers in the mining industry is the art of the impossible. It has been the art of the impossible because it has been the art of trying to make a fundamental change in a system by using structures and instruments that were designed to perpetuate that system. It lias been the art of the impossible because it has been the art of trying to make a revolution with moderate tools tli at were invented to prevent a revolution. Because of the nature of the mining industry, which is conservative or ultraconservative by any definition, the black miner has been condemned to seek radical ends within a framework which was designed to prevent sudden and radical changes. For almost one hundred years now, black miners have not been able to change their status. The African Miners' Union in 1946 under J B Marks made an attempt but was brutally crushed by a combination of employer and government forces. It is against this background that our union has developed its organising strategies. Organising has taken place around a number of issues, some of which are safety, wages, and working- class unity.
- Full Text:
- Date Issued: 2000
- Authors: SAIRR
- Date: 2000
- Subjects: SAIRR
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/111247 , vital:33420
- Description: When the National Union of Mineworkers was formed an experienced unionist said to me "organising workers in South Africa is the art of the possible". But organising workers in the mining industry is the art of the impossible. It has been the art of the impossible because it has been the art of trying to make a fundamental change in a system by using structures and instruments that were designed to perpetuate that system. It lias been the art of the impossible because it has been the art of trying to make a revolution with moderate tools tli at were invented to prevent a revolution. Because of the nature of the mining industry, which is conservative or ultraconservative by any definition, the black miner has been condemned to seek radical ends within a framework which was designed to prevent sudden and radical changes. For almost one hundred years now, black miners have not been able to change their status. The African Miners' Union in 1946 under J B Marks made an attempt but was brutally crushed by a combination of employer and government forces. It is against this background that our union has developed its organising strategies. Organising has taken place around a number of issues, some of which are safety, wages, and working- class unity.
- Full Text:
- Date Issued: 2000
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