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A watershed study on genetic diversity phylogenetic analysis of the Platypleura plumosa (Hemiptera Cicadidae) complex reveals catchment-specific lineages

- Price, Benjamin W, Barker, Nigel P, Villet, Martin H

Authors: Price, Benjamin W , Barker, Nigel P , Villet, Martin H
Date: 2010
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/441711 , vital:73909 , https://doi.org/10.1016/j.ympev.2009.10.011
Description: Historical biogeography studies have at their disposal a small suite of vicariance models to explain genetic differentiation within and between species. One of these processes involves the role of river catchments and their associated watersheds, in driving diversification and is applicable to both aquatic and terrestrial organisms. Although the idea of catchments structuring the genetic history of aquatic organisms is reasonably well understood, their effect on terrestrial organisms has largely been overlooked, with relevant studies being limited in scope. South Africa presents a perfect test-bed for elucidating this mechanism of diversification due to its rich biodiversity, range of climatic environments and many large river catchments. Here we use the cicadas of the Platypleura plumosa complex to highlight the importance of catchments and their associated watersheds in driving diversification of terrestrial invertebrates that lack an aquatic life-stage. Population structure was found to correspond to primary and in some cases secondary catchments; highlighting the need to include information on catchment structure when formulating hypotheses of population diversification. Recognizing that climate change in the near future is likely to alter the environment, and particularly precipitation patterns, insight into recent patterns of population change related to catchments may be useful in a conservation context.
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Date Issued: 2010

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Ecological impacts of small dams on South African rivers Part 1: Drivers of change–water quantity and quality

- Mantel, Sukhmani K, Hughes, Denis A, Muller, Nikite W J

Authors: Mantel, Sukhmani K , Hughes, Denis A , Muller, Nikite W J
Date: 2010
Subjects: To be catalogued
Language: English
Type: text , report
Identifier: http://hdl.handle.net/10962/438099 , vital:73435 , ISBN 1816-7950 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2398.pdf
Description: Impacts of large dams are well-known and quantifiable, while small dams have generally been perceived as benign, both socially and envi-ronmentally. The present study quantifies the cumulative impacts of small dams on the water quality (physico-chemistry and invertebrate biotic indices) and quantity (discharge) of downstream rivers in 2 South African regions. The information from 2 South African national data-bases was used for evaluating the cumulative impacts on water quality and quantity. Physico-chemistry and biological data were obtained from the River Health Programme, and discharge data at stream flow gauges was obtained from the Hydrological Information System. Multivariate analyses were conducted to establish broad patterns for cumulative impacts of small dams across the 2 regions–Western Cape (winter rain-fall, temperate, south-western coast) and Mpumalanga (summer rain-fall, tropical, eastern coast). Multivariate analyses found that the chang-es in macroinvertebrate indices and the stream’s physico-chemistry were more strongly correlated with the density of small dams in the catchment (as a measure of cumulative impact potential) relative to the storage capacity of large dams. T-tests on the data, not including sam-ples with upstream large dams, indicated that the high density of small dams significantly reduced low flows and increased certain physico-chemistry variables (particularly total dissolved salts) in both the re-gions, along with associated significant reductions in a macroinverte-brate index (SASS4 average score per taxon). Regional differences were apparent in the results for discharge reductions and the macroin-vertebrate index. The results suggest that the cumulative effect of a high number of small dams is impacting the quality and quantity of wa-ters in South African rivers and that these impacts need to be systemat-ically incorporated into the monitoring protocol of the environmental wa-ter requirements.
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Date Issued: 2010

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Ecological impacts of small dams on South African rivers Part 2: Biotic response – abundance and composition of macroinvertebrate communities

- Mantel, Sukhmani K, Muller, Nikite W J, Hughes, Denis A

Authors: Mantel, Sukhmani K , Muller, Nikite W J , Hughes, Denis A
Date: 2010
Language: English
Type: text , Article
Identifier: vital:7095 , http://hdl.handle.net/10962/d1012437
Description: This paper investigates the cumulative impacts of small dams on invertebrate communities in 2 regions of South Africa – the Western Cape and Mpumalanga. Previous research found reduced discharge, increased total dissolved salts, and a decrease in average score per taxon (ASPT; collected using SASS4 methods) at sites with high density of small dams in their catchment. These changes in ASPT are investigated using the invertebrate abundance data available in the River Health Programme. Multivariate analyses found differences in invertebrate communities in rivers with high densities of small dams in their catchment in foothill-gravel streams (in both Western Cape and Mpumalanga) and in foothill-cobble streams (in Western Cape only). Opportunistic taxa that are tolerant of pollution, and capable of exploiting various habitats, and those that prefer slower currents increased in numbers, while other taxa that are sensitive to pollution and disturbance declined in numbers. Some regional differences were noted possibly reflecting climatic differences between the regions. Since the results of this study are correlative, it highlights the need for a systematic (by sites and seasons) and detailed (at species level) collection of data to verify the results of cumulative effects of small dams. This can further the development of a framework for small-dam construction and management that will limit their impact on river catchments.
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Date Issued: 2010

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Ecological impacts of small dams on South African rivers Part 2: Biotic response–abundance and composition of macroinvertebrate communities

- Mantel, Sukhmani K, Muller, Nikite W J, Hughes, Denis A

Authors: Mantel, Sukhmani K , Muller, Nikite W J , Hughes, Denis A
Date: 2010
Subjects: To be catalogued
Language: English
Type: text , report
Identifier: http://hdl.handle.net/10962/438087 , vital:73434 , ISBN 1816-7950 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2354.pdf
Description: This paper investigates the cumulative impacts of small dams on inver-tebrate communities in 2 regions of South Africa–the Western Cape and Mpumalanga. Previous research found reduced discharge, in-creased total dissolved salts, and a decrease in average score per tax-on (ASPT; collected using SASS4 methods) at sites with high density of small dams in their catchment. These changes in ASPT are investigat-ed using the invertebrate abundance data available in the River Health Programme. Multivariate analyses found differences in invertebrate communities in rivers with high densities of small dams in their catch-ment in foothill-gravel streams (in both Western Cape and Mpuma-langa) and in foothill-cobble streams (in Western Cape only). Opportun-istic taxa that are tolerant of pollution, and capable of exploiting various habitats, and those that prefer slower currents increased in numbers, while other taxa that are sensitive to pollution and disturbance declined in numbers. Some regional differences were noted possibly reflecting climatic differences between the regions. Since the results of this study are correlative, it highlights the need for a systematic (by sites and sea-sons) and detailed (at species level) collection of data to verify the re-sults of cumulative effects of small dams. This can further the devel-opment of a framework for small-dam construction and management that will limit their impact on river catchments.
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Date Issued: 2010

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Histological validation of gonadal macroscopic staging criteria for Labeo cylindricus (Pisces: Cyprinidae)

- Booth, Anthony J, Weyl, Olaf L F

Authors: Booth, Anthony J , Weyl, Olaf L F
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/124593 , vital:35634 , https://doi.org/10.1080/15627020.2000.11657094
Description: Histological examination of gametogenesis revealed that the current staging criteria used to assess gonadal recrudescence of the redeye labeo, Labeo cylindricus, were adequate. Gametogenesis was qualitatively similar to that of freshwater teleosts with a clearly defined seasonal reproductive cycle. L. cylindricus undergoes seasonal gross morphological and cytological gonadal changes with previtellogenesis dominating during the winter, vitellogenic development during spring and summer culminating in large-scale spawning at the end of summer. Post-spawning mass atresia of oocytes was evident in autumn. The histological data presented support macroscopical evidence that L. cylindricus is a synchronous iteroparous spawner, reproducing over a short period each year throughout its life-span.
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Date Issued: 2010

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Institutionalising service-learning

- Hlengwa, Amanda I

Authors: Hlengwa, Amanda I
Date: 2010
Language: English
Type: text , article
Identifier: vital:29685 , http://hdl.handle.net/10520/EJC131578
Description: Higher education has three core pillars: teaching, research and community engagement. Teaching and research endeavours have dominated university agendas. However, momentum in prioritising community engagement is growing. The developing emphasis placed on the third pillar raises an opportunity to investigate how community engagement is conceptualised and therefore prioritised within the higher education landscape. Community engagement is expressed as a continuum in higher education inclusive of five overlapping activities of which service-learning is just one. This paper outlines what service-learning is and its potential role in the transformation of higher education, as well as to signal the importance of institutional commitment to service-learning. Lastly, the paper offers a synthesis of the available literature on how to implement successfully service-learning modules.
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Date Issued: 2010

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Natural enemies from South Africa for biological control of Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae) in Europe

- Baars, Jan-Robert, Coetzee, Julie A, Martin, Grant D, Hill, Martin P, Caffrey, J M

Authors: Baars, Jan-Robert , Coetzee, Julie A , Martin, Grant D , Hill, Martin P , Caffrey, J M
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/76914 , vital:30637 , https://doi.org/10.1007/s10750-010-0427-0
Description: The non-native invasive plant, Lagarosiphon major (Hydrocharitaceae) is a submersed aquatic macrophyte that poses a significant threat to water bodies in Europe. Dense infestations prove difficult to manage using traditional methods. In order to initiate a biocontrol programme, a survey for natural enemies of Lagarosiphon was conducted in South Africa. Several phytophagous species were recorded for the first time, with at least three showing notable promise as candidate agents. Amongst these, a leaf-mining fly, Hydrellia sp. (Ephydridae) that occurred over a wide distribution causes significant leaf damage despite high levels of parasitism by braconid wasps. Another yet unidentified fly was recorded mining the stem of L. major. Two leaf-feeding and shoot boring weevils, cf. Bagous sp. (Curculionidae) were recorded damaging the shoot tips and stunting the growth of the stem. Several leaf-feeding lepidopteran species (Nymphulinae) were frequently recorded, but are expected to feed on a wide range of plant species and are not considered for importation before other candidates are assessed. The discovery of several natural enemies in the country of origin improves the biological control prospects of L. major in Europe.
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Date Issued: 2010

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Public green space inequality in small towns in South Africa

- McConnachie, Matthew M, Shackleton, Charlie M

Authors: McConnachie, Matthew M , Shackleton, Charlie M
Date: 2010
Language: English
Type: Article
Identifier: vital:6644 , http://hdl.handle.net/10962/d1006874
Description: The distribution of public green space within towns is frequently uneven, and influenced by attributes such as its location relative to the commercial core, as well as the ethnicity and relative wealth and education of the residents. Yet most studies are from large cities in developed countries. In contrast, this study reports on the distribution of public green space across 9 small towns in a developing country, namely South Africa, which offers a unique case study because of its former racially defined settlement patterns. We do so using GIS analysis of aerial photographs focusing on 3 types of suburbs in each town, defined on the basis of wealth as well as race-based history under the previous apartheid regime. The more affluent suburbs, inhabited mainly by whites, have the lowest density of housing and the highest area of green space per capita. Proportionally, they have a similar area under public green space as to the previously racially defined townships, but because of the lower housing density, they have a greater area per person. The newly built low-cost housing areas (termed RDP suburbs), occupied largely by poor black South Africans, are poorly endowed with public green space, and fare worse than the other 2 suburb types on all attributes measured. This needs to be addressed in further low-cost housing developments.
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Date Issued: 2010

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Reproductive biology of a riverine cyprinid, Labeo umbratus (Teleostei: Cyprinidae), in small South African reservoirs

- Potts, Warren M, Booth, Anthony J, Hecht, Thomas, Andrew, Timothy G

Authors: Potts, Warren M , Booth, Anthony J , Hecht, Thomas , Andrew, Timothy G
Date: 2010
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/125854 , vital:35826 , https://doi.10.2989/16085910509503849
Description: The reproductive and recruitment characteristics of moggel, Labeo umbratus, populations were examined in four small South African reservoirs. Reproduction, characterised by an extended spawning season, high fecundity, short incubation time and rapid larval development, appears to be ideally suited to the highly variable environment of small reservoirs. Evidence suggested that L. umbratus spawns in the reservoirs. In two reservoirs where samples were conducted monthly, GSI (gonado-somatic index) was positively correlated with both water temperature and day length, whilst the CPUE (catch per unit effort) of juveniles was not related to any environmental variable. The success of moggel spawning appeared to increase when there was early spring and consistent summer rainfall.
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Date Issued: 2010

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Technology solutions to strengthen the integration of marginalized communities into the global knowledge society

- Hlungulu, Bulumko, Kunjuzwa, Dumani, Ndlovu, Nyankiso, Samalenge, Jimmy, Sikhumbuzo, Ngwenya, Thinyane, Mamello, Terzoli, Alfredo

Authors: Hlungulu, Bulumko , Kunjuzwa, Dumani , Ndlovu, Nyankiso , Samalenge, Jimmy , Sikhumbuzo, Ngwenya , Thinyane, Mamello , Terzoli, Alfredo
Date: 2010
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/430769 , vital:72714 , https://ieeexplore.ieee.org/abstract/document/5753005
Description: Information and Communication Technology (ICT) has made it possible to explore novel and innovative mechanisms to leap-frog socio-economic development in rural and marginalized communities. An ICT for development intervention called Siyakhula Living Lab (SLL) has been underway in Dwesa, a rural community in the Eastern Cape Prov-ince, for the past four years. The living lab methodology, which enables user-driven innovation within a multi-stakeholder relationship of aca-demia, user communities, government and private industry, has facili-tated greater integration of the Dwesa community into the digital ecolo-gy and subsequently the knowledge society. This paper introduces the SLL intervention, discusses the SLL's supporting technical infrastruc-ture and the interventions that are undertaken towards long-term sus-tainability of the project. The developed eServices are also discussed, with a view to highlighting the key characteristics that contribute to in-creased context-sensitivity, ownership, and buy-in from the community.
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Date Issued: 2010

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Using local experts as benchmarks for household local ecological knowledge: scoring in South African savannas

- Steele, Melita Z, Shackleton, Charlie M

Authors: Steele, Melita Z , Shackleton, Charlie M
Date: 2010
Language: English
Type: Article
Identifier: vital:6660 , http://hdl.handle.net/10962/d1007084
Description: It is well recognised that local ecological knowledge is an important facet of natural resource management in rural regions of the developing world. However, techniques to assess levels and to integrate it into formal or informal management approaches require further development. In particular, quantitative tools are missing, which would allow more robust analysis of the factors that positively or negatively affect local ecological knowledge and vice versa. This paper reports on a quick assessment approach that provides a quantitative score of generalist local ecological knowledge at the household level. It does so by comparing responses to the knowledge of local people identified as experts within the community. In this way it is both locally constructed and contextualized, and thereby avoids pitfalls of trying to score local ecological knowledge relative to conventional scientific knowledge which frequently cannot account for local constructs. The approach is applied at eight villages throughout the savanna biome in South Africa.
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Date Issued: 2010

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