Market profiles and trade in medicinal plants in the Lowveld, South Africa
- Botha, Jenny, Witkowski, Ed T F, Shackleton, Charlie M
- Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
- Date: 2004
- Subjects: Kruger National Park
- Language: English
- Type: Article
- Identifier: vital:6625 , http://hdl.handle.net/10962/d1006817
- Description: Rising demand for medicinal plants has led to increased pressure on wild plant populations. This, combined with shrinking habitats, means that many species in South Africa are now facing local extinction. In 1997, a study was initiated to determine the extent of trade in medicinal plants in the South African Lowveld (the low lying plains to the east of the Drakensberg escarpment), and to investigate socio-economic factors influencing trade and resource management. Trade was not as extensive in the Lowveld as in major urban markets such as Durban or the Witwatersrand (Johannesburg and surrounding towns), either in terms of the quantity, number or range of species sold, or the numbers of people relying on the trade for an income. In markets assessed in Mpumalanga Province, 176 species were identified (71% of the vernacular names encountered in the market place), representing 69 plant families. In Limpopo, 70 different species were identified (84% of the vernacular names encountered in the market place), representing 40 families. Imports were significant in Mpumalanga (33% of the plants on offer), mainly from Mozambique. A detrended correspondence analysis showed substantial differences between species traded in Mpumalanga and those sold in Limpopo. There was little variation in the species stocked by vendors in Mpumalanga, regardless of the season, the attributes of the seller, or whether business was carried out in urban or rural areas. In contrast, there was considerable variation in the stock inventories of the Limpopo traders. Despite the lower levels of local trade, increased harvesting pressure is being experienced regionally, to meet demand in metropolitan centres such as the Witwatersrand. This study showed considerable local variation and complexities in the harvesting and marketing of medicinal plants, with both a national and an international dimension. This dual spatial scale presents both opportunities and challenges in the management of these plants, which need to be addressed simultaneously, particularly with respect to research requirements and development of predictive models and capacity. Cooperation in conservation strategies and policies is required at regional, national and international levels, while ensuring that management initiatives take into account local market conditions and the socio-economic realities facing both consumers and those who depend on the trade for their livelihoods.
- Full Text:
- Date Issued: 2004
- Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
- Date: 2004
- Subjects: Kruger National Park
- Language: English
- Type: Article
- Identifier: vital:6625 , http://hdl.handle.net/10962/d1006817
- Description: Rising demand for medicinal plants has led to increased pressure on wild plant populations. This, combined with shrinking habitats, means that many species in South Africa are now facing local extinction. In 1997, a study was initiated to determine the extent of trade in medicinal plants in the South African Lowveld (the low lying plains to the east of the Drakensberg escarpment), and to investigate socio-economic factors influencing trade and resource management. Trade was not as extensive in the Lowveld as in major urban markets such as Durban or the Witwatersrand (Johannesburg and surrounding towns), either in terms of the quantity, number or range of species sold, or the numbers of people relying on the trade for an income. In markets assessed in Mpumalanga Province, 176 species were identified (71% of the vernacular names encountered in the market place), representing 69 plant families. In Limpopo, 70 different species were identified (84% of the vernacular names encountered in the market place), representing 40 families. Imports were significant in Mpumalanga (33% of the plants on offer), mainly from Mozambique. A detrended correspondence analysis showed substantial differences between species traded in Mpumalanga and those sold in Limpopo. There was little variation in the species stocked by vendors in Mpumalanga, regardless of the season, the attributes of the seller, or whether business was carried out in urban or rural areas. In contrast, there was considerable variation in the stock inventories of the Limpopo traders. Despite the lower levels of local trade, increased harvesting pressure is being experienced regionally, to meet demand in metropolitan centres such as the Witwatersrand. This study showed considerable local variation and complexities in the harvesting and marketing of medicinal plants, with both a national and an international dimension. This dual spatial scale presents both opportunities and challenges in the management of these plants, which need to be addressed simultaneously, particularly with respect to research requirements and development of predictive models and capacity. Cooperation in conservation strategies and policies is required at regional, national and international levels, while ensuring that management initiatives take into account local market conditions and the socio-economic realities facing both consumers and those who depend on the trade for their livelihoods.
- Full Text:
- Date Issued: 2004
Conceptualizing the human use of wild edible herbs for conservation in South African communal areas
- Dovie, Delali B K, Shackleton, Charlie M, Witkowski, Ed T F
- Authors: Dovie, Delali B K , Shackleton, Charlie M , Witkowski, Ed T F
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6626 , http://hdl.handle.net/10962/d1006818
- Description: The importance of wild edible herbaceous species to resource poor households in most rural economies within savannas has been little studied. This is because most of the herbs grow in impoverished species communities and lands, often referred to as ‘marginal lands’. The aim of this paper is to conceptualize how the economics of wild edible herbs to households can be used to add value to total livelihoods and conservation within traditional communal areas of South Africa. Analysis of the economics of the consumption of wild edible herbs in Thorndale (Bushbuckridge district) of the Limpopo province is presented. The majority of households consumed wild edible herbs, averaging 15.4 kg dried weight per household per year and valued at $167 per household. The herbs were mostly harvested from uncultivated areas of farms, and rangelands. There was little correlation between household characteristics and the dependence on wild herbs for food. The local people noted a decline in the availability of the species, although not much is known about attempts to cultivate them. The only reasons attributed to the decline were nutrient poor soils and insufficient rains. With this background, developing a local strategy to sustain the species through cultivation by households was found to be feasible. A multiple-use system for the herbs, their improvement and value addition towards commercialization and increased household usage may result in wider acceptance and subsequent cultivation. Species diversity will be enhanced whilst conserving the land on which they grow. This multiple use system may include species roles in soil and water conservation.
- Full Text:
- Date Issued: 2007
- Authors: Dovie, Delali B K , Shackleton, Charlie M , Witkowski, Ed T F
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6626 , http://hdl.handle.net/10962/d1006818
- Description: The importance of wild edible herbaceous species to resource poor households in most rural economies within savannas has been little studied. This is because most of the herbs grow in impoverished species communities and lands, often referred to as ‘marginal lands’. The aim of this paper is to conceptualize how the economics of wild edible herbs to households can be used to add value to total livelihoods and conservation within traditional communal areas of South Africa. Analysis of the economics of the consumption of wild edible herbs in Thorndale (Bushbuckridge district) of the Limpopo province is presented. The majority of households consumed wild edible herbs, averaging 15.4 kg dried weight per household per year and valued at $167 per household. The herbs were mostly harvested from uncultivated areas of farms, and rangelands. There was little correlation between household characteristics and the dependence on wild herbs for food. The local people noted a decline in the availability of the species, although not much is known about attempts to cultivate them. The only reasons attributed to the decline were nutrient poor soils and insufficient rains. With this background, developing a local strategy to sustain the species through cultivation by households was found to be feasible. A multiple-use system for the herbs, their improvement and value addition towards commercialization and increased household usage may result in wider acceptance and subsequent cultivation. Species diversity will be enhanced whilst conserving the land on which they grow. This multiple use system may include species roles in soil and water conservation.
- Full Text:
- Date Issued: 2007
Valuation of communal area livestock benefits, rural livelihoods and related policy issues
- Dovie, Delali B K, Shackleton, Charlie M, Witkowski, Ed T F
- Authors: Dovie, Delali B K , Shackleton, Charlie M , Witkowski, Ed T F
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6627 , http://hdl.handle.net/10962/d1006819
- Description: The multiple benefits from livestock production to rural households are evaluated in Thorndale, a communal area of the Limpopo Province South Africa. Monetary values of livestock products are presented. Values from most previous studies are static (and thus outdated), as a result of conceptual and methodological shifts. The net monetary value of the direct benefits from livestock was estimated as $656 per household/annum, excluding the holding of cattle for savings. The net value is equivalent to 22.7% of the value of the other livelihood sources that were considered, and inclusive of cash income streams, crops, and secondary woodland resources. A net 168% herd increase in livestock was recorded between 1993 and 1999. More households owned goats compared to cattle, and cattle were important for use as draught power, and for milk. Households without livestock benefited through gifts and services, valued at $33 per household/annum. Policy concerns are the provision of adequate market and pricing mechanisms for communal area livestock, tailored savings, investment support, credit schemes, and infrastructure. An appropriate multipurpose benefit production model, other than a commercialised model is suggested for the sector.
- Full Text:
- Date Issued: 2006
- Authors: Dovie, Delali B K , Shackleton, Charlie M , Witkowski, Ed T F
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6627 , http://hdl.handle.net/10962/d1006819
- Description: The multiple benefits from livestock production to rural households are evaluated in Thorndale, a communal area of the Limpopo Province South Africa. Monetary values of livestock products are presented. Values from most previous studies are static (and thus outdated), as a result of conceptual and methodological shifts. The net monetary value of the direct benefits from livestock was estimated as $656 per household/annum, excluding the holding of cattle for savings. The net value is equivalent to 22.7% of the value of the other livelihood sources that were considered, and inclusive of cash income streams, crops, and secondary woodland resources. A net 168% herd increase in livestock was recorded between 1993 and 1999. More households owned goats compared to cattle, and cattle were important for use as draught power, and for milk. Households without livestock benefited through gifts and services, valued at $33 per household/annum. Policy concerns are the provision of adequate market and pricing mechanisms for communal area livestock, tailored savings, investment support, credit schemes, and infrastructure. An appropriate multipurpose benefit production model, other than a commercialised model is suggested for the sector.
- Full Text:
- Date Issued: 2006
The potential for voluntary instruments to achieve conservation planning goals : the case of conservancies in South Africa
- Downsborough, Linda, Shackleton, Charlie M, Knight, Andrew T
- Authors: Downsborough, Linda , Shackleton, Charlie M , Knight, Andrew T
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6629 , http://hdl.handle.net/10962/d1006821
- Description: Spatial prioritizations and gap analyses are increasingly undertaken to allocate conservation resources. Most spatial prioritizations are conducted without specifying the conservation instruments to be implemented and gap analyses typically assess formally protected areas but increasingly include private land conservation instruments. We examine conservancies to see if these voluntary instruments contribute towards achieving goals of South African conservation planning initiatives. We conducted a nationwide survey and interviews with conservancy members in Gauteng and the Eastern Cape. Conservancies have potential for assisting South Africa to achieve conservation planning goals at national and local scales but their inclusion in spatial prioritizations and gap analyses predicates improved protection for nature, operational refinement and increased support. We sound a warning to conservation planning initiatives that incorporate voluntary instruments on private land, and present recommendations for strengthening such instruments to make them more effective. Our findings may assist conservation planners elsewhere to design more effective conservation planning initiatives focused on private land.
- Full Text:
- Date Issued: 2011
- Authors: Downsborough, Linda , Shackleton, Charlie M , Knight, Andrew T
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6629 , http://hdl.handle.net/10962/d1006821
- Description: Spatial prioritizations and gap analyses are increasingly undertaken to allocate conservation resources. Most spatial prioritizations are conducted without specifying the conservation instruments to be implemented and gap analyses typically assess formally protected areas but increasingly include private land conservation instruments. We examine conservancies to see if these voluntary instruments contribute towards achieving goals of South African conservation planning initiatives. We conducted a nationwide survey and interviews with conservancy members in Gauteng and the Eastern Cape. Conservancies have potential for assisting South Africa to achieve conservation planning goals at national and local scales but their inclusion in spatial prioritizations and gap analyses predicates improved protection for nature, operational refinement and increased support. We sound a warning to conservation planning initiatives that incorporate voluntary instruments on private land, and present recommendations for strengthening such instruments to make them more effective. Our findings may assist conservation planners elsewhere to design more effective conservation planning initiatives focused on private land.
- Full Text:
- Date Issued: 2011
Urban-rural contrasts in Arbor Week in South Africa
- Guthrie, G, Shackleton, Charlie M
- Authors: Guthrie, G , Shackleton, Charlie M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6631 , http://hdl.handle.net/10962/d1006823
- Description: Trees provide people with environmental benefits. Greening projects have been implemented worldwide, but many of them have frustratingly low participation levels. In South Africa, tree-planting campaigns such as the national Arbor Week are generally aimed at schools. Because of the remoteness of rural schools, there are urban / rural disparities in standards of education, infrastructure and support provided at schools, and hence we hypothesized that these disparities would be mirrored in tree-planting activities associated with national Arbor Week. In the study reported here, 236 urban and rural schools were assessed by means of postal surveys and subsampled via direct interviews, as to their participation in Arbor Week activities, the provision of trees, constraints to participation, and the perceived benefits of planting trees. Very few urban schools had never participated in any Arbor Week activities, whereas one-fifth of rural ones had never participated in any way. Urban schools participated in a greater number of Arbor Week activities than rural schools, including tree-planting, displaying posters and having speeches. Thus, overall information about Arbor Week is lacking in rural areas compared to urban ones. Rural schools derived more benefits from planting trees, with shade and education being the primary benefits overall. Rural schools were supplied with trees by NGOs, whereas urban schools received trees from individual or company donations. The major constraints to tree-planting are livestock damage, water shortages, vandalism and theft. These obstacles need to be addressed in a holistic fashion in order to improve the participation and success of National Arbor Week as a vehicle for tree-planting and environmental awareness.
- Full Text:
- Date Issued: 2006
- Authors: Guthrie, G , Shackleton, Charlie M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6631 , http://hdl.handle.net/10962/d1006823
- Description: Trees provide people with environmental benefits. Greening projects have been implemented worldwide, but many of them have frustratingly low participation levels. In South Africa, tree-planting campaigns such as the national Arbor Week are generally aimed at schools. Because of the remoteness of rural schools, there are urban / rural disparities in standards of education, infrastructure and support provided at schools, and hence we hypothesized that these disparities would be mirrored in tree-planting activities associated with national Arbor Week. In the study reported here, 236 urban and rural schools were assessed by means of postal surveys and subsampled via direct interviews, as to their participation in Arbor Week activities, the provision of trees, constraints to participation, and the perceived benefits of planting trees. Very few urban schools had never participated in any Arbor Week activities, whereas one-fifth of rural ones had never participated in any way. Urban schools participated in a greater number of Arbor Week activities than rural schools, including tree-planting, displaying posters and having speeches. Thus, overall information about Arbor Week is lacking in rural areas compared to urban ones. Rural schools derived more benefits from planting trees, with shade and education being the primary benefits overall. Rural schools were supplied with trees by NGOs, whereas urban schools received trees from individual or company donations. The major constraints to tree-planting are livestock damage, water shortages, vandalism and theft. These obstacles need to be addressed in a holistic fashion in order to improve the participation and success of National Arbor Week as a vehicle for tree-planting and environmental awareness.
- Full Text:
- Date Issued: 2006
Abundance and commercialization of Phoenix Reclinata in the King Williamstown area, South Africa
- Gyan, C A, Shackleton, Charlie M
- Authors: Gyan, C A , Shackleton, Charlie M
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6634 , http://hdl.handle.net/10962/d1006829
- Description: In the Eastern Cape of South Africa the fronds of the wild palm Phoenix reclinata are harvested by rural women and manufactured into hand brushes, which are sold in urban centres. This paper reports on the abundance of P. reclinata palms, the profile of the harvesters, and the economic returns from trading in palm brushes as a case study of locally driven non-timber forest product commercialization. The palm resource was in a reasonable state with most clumps being lightly (36%) or moderately (43%) harvested, with many others uncut due to physical or culturally defined refugia. Tall trees within a clump were uncut because the fronds were too high. The estimated production of fronds was less than 25 per cent of the local demand. Consequently, harvesters were seeking alternative areas and species. Mean gross monthly income was R475 (USD45) which was an important cash contribution. Net income was 75 per cent of this. Income earned per seller was influenced by factors such as age, education, hours in the trade, and whether any household member received an old-age pension from the State. Older and less educated sellers had been trading longer than younger or more educated vendors.
- Full Text:
- Date Issued: 2005
- Authors: Gyan, C A , Shackleton, Charlie M
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6634 , http://hdl.handle.net/10962/d1006829
- Description: In the Eastern Cape of South Africa the fronds of the wild palm Phoenix reclinata are harvested by rural women and manufactured into hand brushes, which are sold in urban centres. This paper reports on the abundance of P. reclinata palms, the profile of the harvesters, and the economic returns from trading in palm brushes as a case study of locally driven non-timber forest product commercialization. The palm resource was in a reasonable state with most clumps being lightly (36%) or moderately (43%) harvested, with many others uncut due to physical or culturally defined refugia. Tall trees within a clump were uncut because the fronds were too high. The estimated production of fronds was less than 25 per cent of the local demand. Consequently, harvesters were seeking alternative areas and species. Mean gross monthly income was R475 (USD45) which was an important cash contribution. Net income was 75 per cent of this. Income earned per seller was influenced by factors such as age, education, hours in the trade, and whether any household member received an old-age pension from the State. Older and less educated sellers had been trading longer than younger or more educated vendors.
- Full Text:
- Date Issued: 2005
Efficacy of solar power units for small-scale businesses in a remote rural area, South Africa
- Hajat, A, Banks, D, Aiken, R, Shackleton, Charlie M
- Authors: Hajat, A , Banks, D , Aiken, R , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6636 , http://hdl.handle.net/10962/d1006860
- Description: Much work has considered the practicalities and affordability of solar systems for domestic energy supplies in remote rural areas. There is less understanding of its utility for small-scale business enterprises in such areas. We examined the patterns of use of two 12 V and one 24 V systems for small-scale enterprises housed in transportable containers. Monitoring of load shed and top of charge indicated that the 12 V systems were inadequate to meet the requirements of the enterprises. The 24 V operation performed a lot better. Despite some technical limitations the system offered a number of social, economic and environmental positives; primarily the offering of business products not otherwise available in the area, incomes to the entrepreneurs and greater connectivity with regional centres through office services such as cell-phone charging and faxing. Customers of the small-scale enterprises felt that their presence in the area saved them some money because they no longer had to travel as frequently to regional urban centres.
- Full Text:
- Date Issued: 2009
- Authors: Hajat, A , Banks, D , Aiken, R , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6636 , http://hdl.handle.net/10962/d1006860
- Description: Much work has considered the practicalities and affordability of solar systems for domestic energy supplies in remote rural areas. There is less understanding of its utility for small-scale business enterprises in such areas. We examined the patterns of use of two 12 V and one 24 V systems for small-scale enterprises housed in transportable containers. Monitoring of load shed and top of charge indicated that the 12 V systems were inadequate to meet the requirements of the enterprises. The 24 V operation performed a lot better. Despite some technical limitations the system offered a number of social, economic and environmental positives; primarily the offering of business products not otherwise available in the area, incomes to the entrepreneurs and greater connectivity with regional centres through office services such as cell-phone charging and faxing. Customers of the small-scale enterprises felt that their presence in the area saved them some money because they no longer had to travel as frequently to regional urban centres.
- Full Text:
- Date Issued: 2009
Quantity and significance of wild meat off-take by a rural community in the Eastern Cape, South Africa
- Kaschula, Sarah A H, Shackleton, Charlie M
- Authors: Kaschula, Sarah A H , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6638 , http://hdl.handle.net/10962/d1006864
- Description: When compared to tropical forest zones in west and central Africa, off-take of wild meat from savannah and grassland biomes by local rural communities has not been well assessed. This case study of wild meat collection activities within a rural community in the Mount Frere region of the Eastern Cape (South Africa) uses last-catch records derived from 50 wild meat gatherers to calculate average off-take of taxa, species and fresh mass of wild meat per collection event. When per-event off take is overlaid onto household hunting frequency data, annual off-take would be 268.6 kg km−2 yr−1 or 3 kg person−1 yr−1 presuming constant off-take over an annual period. Monetary value of off-take would be South African R 307 (US$ 39) per household annually. For some species, off-take weight per km2 shows similar values to data from tropical forest zones, but high human population densities tend to dilute off-takes to less nutritionally significant amounts at the per person scale. However, unlike many tropical zones, none of the species harvested can be considered high-priority conservation species. Even densely populated and heavily harvested communal lands appear to offer high wild meat off-takes from low conservation priority species.
- Full Text:
- Date Issued: 2009
- Authors: Kaschula, Sarah A H , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6638 , http://hdl.handle.net/10962/d1006864
- Description: When compared to tropical forest zones in west and central Africa, off-take of wild meat from savannah and grassland biomes by local rural communities has not been well assessed. This case study of wild meat collection activities within a rural community in the Mount Frere region of the Eastern Cape (South Africa) uses last-catch records derived from 50 wild meat gatherers to calculate average off-take of taxa, species and fresh mass of wild meat per collection event. When per-event off take is overlaid onto household hunting frequency data, annual off-take would be 268.6 kg km−2 yr−1 or 3 kg person−1 yr−1 presuming constant off-take over an annual period. Monetary value of off-take would be South African R 307 (US$ 39) per household annually. For some species, off-take weight per km2 shows similar values to data from tropical forest zones, but high human population densities tend to dilute off-takes to less nutritionally significant amounts at the per person scale. However, unlike many tropical zones, none of the species harvested can be considered high-priority conservation species. Even densely populated and heavily harvested communal lands appear to offer high wild meat off-takes from low conservation priority species.
- Full Text:
- Date Issued: 2009
The distribution, abundance and composition of street trees in selected towns of the Eastern Cape, South Africa
- Kuruneri-Chitepo, C, Shackleton, Charlie M
- Authors: Kuruneri-Chitepo, C , Shackleton, Charlie M
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6639 , http://hdl.handle.net/10962/d1006865
- Description: Street trees are an important component of the urban forest as they provide critical ecosystem services which contribute to human health and environmental quality. However, little is known about the distribution, diversity and density of street trees, particularly in the developing world where urbanisation is most rapid. Thus, the aim of this paper was to assess the distribution, composition and abundance of street trees across three towns along an environmental gradient in the Eastern Cape of South Africa, and identify the key challenges faced by local officials concerned with the provision of street trees. In each town, streets were randomly sampled in the commercial, affluent residential, township settlement and low cost housing areas under the Reconstruction and Development Program (RDP). Attributes recorded per tree were species, circumference, height and health, while semi-structured interviews were conducted with the municipal officials involved in the establishment and maintenance of street trees. A total of 1,485 trees were encountered, comprising 61 species. The majority (56%) of trees were alien species. Noticeable differences in tree density and species richness were evident across suburbs, being highest in the more affluent suburbs and poorly represented in the low income township and RDP areas. There was a decreasing mean tree height and health score along the environmental gradient from the coastal town to the inland town. Although awareness of the benefits of street trees was high, as was the need to reduce the proportion of alien species, the primary constraint to establishment and maintenance of street trees in the three towns was limited budget and human resources.
- Full Text:
- Date Issued: 2011
- Authors: Kuruneri-Chitepo, C , Shackleton, Charlie M
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6639 , http://hdl.handle.net/10962/d1006865
- Description: Street trees are an important component of the urban forest as they provide critical ecosystem services which contribute to human health and environmental quality. However, little is known about the distribution, diversity and density of street trees, particularly in the developing world where urbanisation is most rapid. Thus, the aim of this paper was to assess the distribution, composition and abundance of street trees across three towns along an environmental gradient in the Eastern Cape of South Africa, and identify the key challenges faced by local officials concerned with the provision of street trees. In each town, streets were randomly sampled in the commercial, affluent residential, township settlement and low cost housing areas under the Reconstruction and Development Program (RDP). Attributes recorded per tree were species, circumference, height and health, while semi-structured interviews were conducted with the municipal officials involved in the establishment and maintenance of street trees. A total of 1,485 trees were encountered, comprising 61 species. The majority (56%) of trees were alien species. Noticeable differences in tree density and species richness were evident across suburbs, being highest in the more affluent suburbs and poorly represented in the low income township and RDP areas. There was a decreasing mean tree height and health score along the environmental gradient from the coastal town to the inland town. Although awareness of the benefits of street trees was high, as was the need to reduce the proportion of alien species, the primary constraint to establishment and maintenance of street trees in the three towns was limited budget and human resources.
- Full Text:
- Date Issued: 2011
Changing energy profiles and consumption patterns following electrification in five rural villages, South Africa
- Madubansi, Mainza, Shackleton, Charlie M
- Authors: Madubansi, Mainza , Shackleton, Charlie M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6640 , http://hdl.handle.net/10962/d1006866
- Description: Following the democratic transition in South Africa in the early 1990s the government has implemented a widespread electrification programme, as well as introduced a free basic electricity allowance as a means of poverty alleviation. Yet there are limited longitudinal studies on the impacts of the introduction of electricity on the patterns of household energy use, and even more so in the neglected rural sector. This study reports on the patterns of household energy use in five rural settlements in 1991 and again in 2002. Results indicate a changing pattern of energy use for lighting and powering entertainment appliances, more specifically from dry-cell batteries and paraffin to electricity. Yet for thermal needs, most notably cooking, fuelwood has remained the most widespread fuel, and the amount used per month has not changed, despite increasing scarcity of wood in the local environment. There has been an increase in the proportion of households purchasing fuelwood as opposed to collecting their own. Overall, the mean total number of fuel types used per household has increased, indicating that electricity is simply viewed as an additional energy, rather than an alternative. Yet, electricity accounted for approximately 60% of expenditure on energy sources in 2002, despite the government's policy of a free basic allowance of 5–6 kWh per month. This has implications for energy supply costing, as well as the poverty alleviation dimensions of the whole programme.
- Full Text:
- Date Issued: 2006
- Authors: Madubansi, Mainza , Shackleton, Charlie M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6640 , http://hdl.handle.net/10962/d1006866
- Description: Following the democratic transition in South Africa in the early 1990s the government has implemented a widespread electrification programme, as well as introduced a free basic electricity allowance as a means of poverty alleviation. Yet there are limited longitudinal studies on the impacts of the introduction of electricity on the patterns of household energy use, and even more so in the neglected rural sector. This study reports on the patterns of household energy use in five rural settlements in 1991 and again in 2002. Results indicate a changing pattern of energy use for lighting and powering entertainment appliances, more specifically from dry-cell batteries and paraffin to electricity. Yet for thermal needs, most notably cooking, fuelwood has remained the most widespread fuel, and the amount used per month has not changed, despite increasing scarcity of wood in the local environment. There has been an increase in the proportion of households purchasing fuelwood as opposed to collecting their own. Overall, the mean total number of fuel types used per household has increased, indicating that electricity is simply viewed as an additional energy, rather than an alternative. Yet, electricity accounted for approximately 60% of expenditure on energy sources in 2002, despite the government's policy of a free basic allowance of 5–6 kWh per month. This has implications for energy supply costing, as well as the poverty alleviation dimensions of the whole programme.
- Full Text:
- Date Issued: 2006
Changes in fuelwood use and selection following electrification in the Bushbuckridge lowveld, South Africa
- Madubansi, Mainza, Shackleton, Charlie M
- Authors: Madubansi, Mainza , Shackleton, Charlie M
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6641 , http://hdl.handle.net/10962/d1006867
- Description: Fuelwood is the primary energy source for domestic purposes throughout the developing world, in both urban and rural environments. Due to the detrimental impacts of biomass use on human and environmental health, many governments have sought to reduce its use through provision of potentially cleaner energies, of which electricity is the dominant form. Yet there are surprisingly few studies of changes in fuelwood use following the introduction of electricity, especially in rural areas of Africa. This paper reports on a longitudinal study of fuelwood use, using identical approaches, in five rural villages in the Bushbuckridge region of South Africa, spanning the period over which electricity became widely available. Almost a decade after the introduction of electricity, over 90% of households still used fuelwood for thermal purposes, especially cooking, and the mean household consumption rates over the 11-year period had not changed, even with a policy of 6 kWh per month of free electricity. The proportion of households purchasing fuelwood had increased, probably in response to a number of factors, including (i) increased fuelwood scarcity in the local environment as reflected by increased fuelwood collection times, changes in fuelwood species preferences, and ranking of scarcity by local collectors, and (ii) increases in the price of fuelwood well below that of other fuels and the prevailing inflation rate. Overall, there was an increase in the number of species harvested over the 11-year period. The implications of these findings for rural energy provision are discussed.
- Full Text:
- Date Issued: 2007
- Authors: Madubansi, Mainza , Shackleton, Charlie M
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6641 , http://hdl.handle.net/10962/d1006867
- Description: Fuelwood is the primary energy source for domestic purposes throughout the developing world, in both urban and rural environments. Due to the detrimental impacts of biomass use on human and environmental health, many governments have sought to reduce its use through provision of potentially cleaner energies, of which electricity is the dominant form. Yet there are surprisingly few studies of changes in fuelwood use following the introduction of electricity, especially in rural areas of Africa. This paper reports on a longitudinal study of fuelwood use, using identical approaches, in five rural villages in the Bushbuckridge region of South Africa, spanning the period over which electricity became widely available. Almost a decade after the introduction of electricity, over 90% of households still used fuelwood for thermal purposes, especially cooking, and the mean household consumption rates over the 11-year period had not changed, even with a policy of 6 kWh per month of free electricity. The proportion of households purchasing fuelwood had increased, probably in response to a number of factors, including (i) increased fuelwood scarcity in the local environment as reflected by increased fuelwood collection times, changes in fuelwood species preferences, and ranking of scarcity by local collectors, and (ii) increases in the price of fuelwood well below that of other fuels and the prevailing inflation rate. Overall, there was an increase in the number of species harvested over the 11-year period. The implications of these findings for rural energy provision are discussed.
- Full Text:
- Date Issued: 2007
Has deregulation of non-timber forest product controls and marketing in Orissa state (India) affected local patterns of use and marketing
- Mahapatra, A K, Shackleton, Charlie M
- Authors: Mahapatra, A K , Shackleton, Charlie M
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6643 , http://hdl.handle.net/10962/d1006872
- Description: State control of marketing agricultural or forestry products may lead to a trade monopoly and restricted competition, resulting in inequitable returns to producers. Consequently, market deregulation for agriculture and other natural products has been advocated to improve market efficiencies, participation and returns for the producers and local traders. The study examines the impact of deregulation of state marketing controls on collection, sale and returns to extractors and traders from non-timber forest products. It assessed whether deregulation policy resulted in greater benefits to primary extractors and a win–win situation for both producers and traders? Mixed effects were found, with no significant changes in terms of trade, demand, or quantum of consumption; but there was an overall increase in the procurement price for several products following deregulation. The collection and farm gate price of tree based oilseeds and honey increased due to lower transaction costs, and ease of trading with a continued demand for these products. The impact on less valuable products was insignificant. Abolition of monopolistic trading increased competition and had a pull effect on the local market prices of several NTFPs. Although traders paid a higher price to procure products, overall they also benefited being able to sell the purchased products to merchants and manufacturers at a better margin than previously.
- Full Text:
- Date Issued: 2011
- Authors: Mahapatra, A K , Shackleton, Charlie M
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6643 , http://hdl.handle.net/10962/d1006872
- Description: State control of marketing agricultural or forestry products may lead to a trade monopoly and restricted competition, resulting in inequitable returns to producers. Consequently, market deregulation for agriculture and other natural products has been advocated to improve market efficiencies, participation and returns for the producers and local traders. The study examines the impact of deregulation of state marketing controls on collection, sale and returns to extractors and traders from non-timber forest products. It assessed whether deregulation policy resulted in greater benefits to primary extractors and a win–win situation for both producers and traders? Mixed effects were found, with no significant changes in terms of trade, demand, or quantum of consumption; but there was an overall increase in the procurement price for several products following deregulation. The collection and farm gate price of tree based oilseeds and honey increased due to lower transaction costs, and ease of trading with a continued demand for these products. The impact on less valuable products was insignificant. Abolition of monopolistic trading increased competition and had a pull effect on the local market prices of several NTFPs. Although traders paid a higher price to procure products, overall they also benefited being able to sell the purchased products to merchants and manufacturers at a better margin than previously.
- Full Text:
- Date Issued: 2011
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.
- Full Text:
- Date Issued: 2010
- 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.
- Full Text:
- Date Issued: 2010
The extent of public green space and alien plant species in 10 small towns of the sub-tropical Thicket Biome, South Africa
- McConnachie, Matthew M, Shackleton, Charlie M, McGregor, Gillian K
- Authors: McConnachie, Matthew M , Shackleton, Charlie M , McGregor, Gillian K
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6713 , http://hdl.handle.net/10962/d1006755
- Description: Urban areas in developing countries will accommodate nearly 90% of the projected world population increase between 1995 and 2030. Despite this, few studies, especially in smaller towns, have been carried out on urban green space areas in the developing world. This paper makes a first step in this regard, reporting on the extent and state of urban green spaces within 10 small towns in the Eastern Cape (South Africa). After measuring the size and state (in terms of woody plant cover) of public green space, we then sought patterns across the 10 towns between green space attributes, such as area, density, mean size and proportion of alien or indigenous, with socio-economic attributes of the towns. The area and state of current public green space varied markedly between the towns, with the poorer towns faring the worst. Lower income levels were significantly negatively correlated with the area and quality of public green space. Despite this, human population density and per capita green space were the best predictors of the proportion and mean area of public green space present in the towns. The proportion of town green space and the per capita green space were the best predictors of changes in woody plant composition and density.
- Full Text:
- Date Issued: 2008
- Authors: McConnachie, Matthew M , Shackleton, Charlie M , McGregor, Gillian K
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6713 , http://hdl.handle.net/10962/d1006755
- Description: Urban areas in developing countries will accommodate nearly 90% of the projected world population increase between 1995 and 2030. Despite this, few studies, especially in smaller towns, have been carried out on urban green space areas in the developing world. This paper makes a first step in this regard, reporting on the extent and state of urban green spaces within 10 small towns in the Eastern Cape (South Africa). After measuring the size and state (in terms of woody plant cover) of public green space, we then sought patterns across the 10 towns between green space attributes, such as area, density, mean size and proportion of alien or indigenous, with socio-economic attributes of the towns. The area and state of current public green space varied markedly between the towns, with the poorer towns faring the worst. Lower income levels were significantly negatively correlated with the area and quality of public green space. Despite this, human population density and per capita green space were the best predictors of the proportion and mean area of public green space present in the towns. The proportion of town green space and the per capita green space were the best predictors of changes in woody plant composition and density.
- Full Text:
- Date Issued: 2008
Is HIV/AIDS jeopardizing biodiversity?
- McGarry, Dylan K, Shackleton, Charlie M
- Authors: McGarry, Dylan K , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6642 , http://hdl.handle.net/10962/d1006871
- Description: The scourge of HIV/AIDS (human immunodeficiency virus/acquired immune deficiency syndrome) is most prevalent in southern Africa. South Africa has the highest number of people in the world living with HIV/AIDS and a prevalence rate of over 30 % for females presenting at antenatal clinics. There are now almost five million orphans within southern Africa, as a result of AIDS deaths of one or more or their parents. AIDS-related mortality and morbidity of care-givers may lead to increased reliance on wild sources of animal protein by surviving children. This increase in hunting pressure has unknown, but potentially important impacts on local animal populations.
- Full Text:
- Date Issued: 2009
- Authors: McGarry, Dylan K , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6642 , http://hdl.handle.net/10962/d1006871
- Description: The scourge of HIV/AIDS (human immunodeficiency virus/acquired immune deficiency syndrome) is most prevalent in southern Africa. South Africa has the highest number of people in the world living with HIV/AIDS and a prevalence rate of over 30 % for females presenting at antenatal clinics. There are now almost five million orphans within southern Africa, as a result of AIDS deaths of one or more or their parents. AIDS-related mortality and morbidity of care-givers may lead to increased reliance on wild sources of animal protein by surviving children. This increase in hunting pressure has unknown, but potentially important impacts on local animal populations.
- Full Text:
- Date Issued: 2009
The effectiveness of schools-based National Arbor Week activities in greening of urban homesteads : a case study of Grahamstown, South Africa
- Parkin, Fiona, Shackleton, Charlie M, Schudel, Ingrid J
- Authors: Parkin, Fiona , Shackleton, Charlie M , Schudel, Ingrid J
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6645 , http://hdl.handle.net/10962/d1006885
- Description: Arbor Day, or Week, is a well-established greening initiative worldwide, focusing on tree planting and the benefits thereof. Frequently most effort is targeted at institutions such as schools and community groups. Yet there has been limited assessment of the success of Arbor Day, or Week, activities both at the schools, or the wider dissemination in neighbouring communities and suburbs. The objective of this study was to determine the influence of school-based Arbor Week activities on learners’ home-based practices regarding tree planting and urban forestry. Learners from three schools in Grahamstown, South Africa, with good Arbor Week participation, were assessed on their tree planting knowledge. The learners’ parents were also interviewed to determine whether the information obtained by the learners at school was taken home. A control group consisting of people with no children or very young children was also assessed. This study found that Arbor Week activities were, for the most part, successfully taught in the case study schools, and most of the learners stated that their knowledge of trees and their benefits came from their school activities. However, many learners could not remember the activities in which their schools partook the previous year. Whilst most learners were aware of the importance of trees, few had encouraged tree planting at home. However, over one-fifth of adults claimed that their knowledge of the benefits of trees was as a consequence of Arbor Day activities when they were young. Numerous constraints to tree planting were provided by learners and both the adult groups, the two most frequent being limited space and falling leaves making their yards untidy. External organisations should become more actively involved and provide much needed support systems if greening initiatives are to reach the wider community.
- Full Text:
- Date Issued: 2006
- Authors: Parkin, Fiona , Shackleton, Charlie M , Schudel, Ingrid J
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6645 , http://hdl.handle.net/10962/d1006885
- Description: Arbor Day, or Week, is a well-established greening initiative worldwide, focusing on tree planting and the benefits thereof. Frequently most effort is targeted at institutions such as schools and community groups. Yet there has been limited assessment of the success of Arbor Day, or Week, activities both at the schools, or the wider dissemination in neighbouring communities and suburbs. The objective of this study was to determine the influence of school-based Arbor Week activities on learners’ home-based practices regarding tree planting and urban forestry. Learners from three schools in Grahamstown, South Africa, with good Arbor Week participation, were assessed on their tree planting knowledge. The learners’ parents were also interviewed to determine whether the information obtained by the learners at school was taken home. A control group consisting of people with no children or very young children was also assessed. This study found that Arbor Week activities were, for the most part, successfully taught in the case study schools, and most of the learners stated that their knowledge of trees and their benefits came from their school activities. However, many learners could not remember the activities in which their schools partook the previous year. Whilst most learners were aware of the importance of trees, few had encouraged tree planting at home. However, over one-fifth of adults claimed that their knowledge of the benefits of trees was as a consequence of Arbor Day activities when they were young. Numerous constraints to tree planting were provided by learners and both the adult groups, the two most frequent being limited space and falling leaves making their yards untidy. External organisations should become more actively involved and provide much needed support systems if greening initiatives are to reach the wider community.
- Full Text:
- Date Issued: 2006
The role of non-timber forest products in household coping strategies in South Africa: the influence of household wealth and gender
- Paumgarten, Fiona, Shackleton, Charlie M
- Authors: Paumgarten, Fiona , Shackleton, Charlie M
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6648 , http://hdl.handle.net/10962/d1006897
- Description: The prevalence and ranking of non-timber forest products (NTFPs) as safety-nets has been well discussed, but rarely quantified. We report on group discussions and household interviews in two South African villages to assess the frequency and nature of shocks and stresses over a 2-year period and the coping strategies employed, stratified by household wealth and gender of the de jure household head. Overall, kinship was the most widely adopted coping strategy, and NTFPs were the fifth most prevalent (employed by 70% of households). There were relatively few differences in the nature of shocks or responses between male- and female-headed households. Wealth influenced the experience of shocks or stresses as well as responses. Poorer households have fewer options with the increased use or sale of NTFPs being the second most commonly adopted strategy. Increased use and sale of NTFPs is a common manifestation of the safety-net function. To reconcile long-term economic development and biodiversity conservation, it is important to understand people’s use of natural resources and the factors that affect this use, including their responses to shocks and stresses.
- Full Text:
- Date Issued: 2011
- Authors: Paumgarten, Fiona , Shackleton, Charlie M
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6648 , http://hdl.handle.net/10962/d1006897
- Description: The prevalence and ranking of non-timber forest products (NTFPs) as safety-nets has been well discussed, but rarely quantified. We report on group discussions and household interviews in two South African villages to assess the frequency and nature of shocks and stresses over a 2-year period and the coping strategies employed, stratified by household wealth and gender of the de jure household head. Overall, kinship was the most widely adopted coping strategy, and NTFPs were the fifth most prevalent (employed by 70% of households). There were relatively few differences in the nature of shocks or responses between male- and female-headed households. Wealth influenced the experience of shocks or stresses as well as responses. Poorer households have fewer options with the increased use or sale of NTFPs being the second most commonly adopted strategy. Increased use and sale of NTFPs is a common manifestation of the safety-net function. To reconcile long-term economic development and biodiversity conservation, it is important to understand people’s use of natural resources and the factors that affect this use, including their responses to shocks and stresses.
- Full Text:
- Date Issued: 2011
Wealth differentiation in household use and trade in non-timber forest products in South Africa
- Paumgarten, Fiona, Shackleton, Charlie M
- Authors: Paumgarten, Fiona , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6646 , http://hdl.handle.net/10962/d1006892
- Description: Findings from southern Africa and internationally indicate the local use and trade of NTFPs to be significant however most present a composite picture, failing to account for intra-community socio-economic differences. These differences may have implications for policy and practice related to poverty alleviation and sustainable use. This paper reports on a study in South Africa which explored the relationship between household wealth and the use, procurement and sale of NTFPs in two villages. There was no influence of wealth on the proportion of households using or purchasing most of the NTFPs, or the number used. However, wealthier households bought significantly more resources per household, and poor households (at one village) sold significantly more. These results are discussed within the context of local conditions and poverty alleviation debates.
- Full Text:
- Date Issued: 2009
- Authors: Paumgarten, Fiona , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6646 , http://hdl.handle.net/10962/d1006892
- Description: Findings from southern Africa and internationally indicate the local use and trade of NTFPs to be significant however most present a composite picture, failing to account for intra-community socio-economic differences. These differences may have implications for policy and practice related to poverty alleviation and sustainable use. This paper reports on a study in South Africa which explored the relationship between household wealth and the use, procurement and sale of NTFPs in two villages. There was no influence of wealth on the proportion of households using or purchasing most of the NTFPs, or the number used. However, wealthier households bought significantly more resources per household, and poor households (at one village) sold significantly more. These results are discussed within the context of local conditions and poverty alleviation debates.
- Full Text:
- Date Issued: 2009
Fuelwood harvesting and selection in Valley Thicket, South Africa
- Pote, J, Shackleton, Charlie M, Cocks, Michelle L, Lubke, Roy
- Authors: Pote, J , Shackleton, Charlie M , Cocks, Michelle L , Lubke, Roy
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6531 , http://hdl.handle.net/10962/d1005972
- Description: The Thicket Biome is the second smallest biome in South Africa, and is renowned for its high biodiversity. Yet, less than 5% of the biome is in formal conservation areas. Much of the currently intact thicket outside protected areas is threatened by land transformation to commercial agriculture or heavy use by rural communities. There is limited understanding of the ecological structure and function of thicket communities and their response to these human pressures. This paper reports on a study to characterize the woody communities in Valley Thicket and Thornveld surrounding a rural village. We also examined the demand and selection for specific woody species. There was a marked selection for key species for different uses, including fuelwood, construction timber, and cultural stacks. There was also strong selection for specific size classes of stem, especially those between 16–45 cm circumference. The density, biomass and species richness of woody species was reduced close to the village, and increased with distance away from human settlement. A similar trend was found for the basal area of preferred species, but not for the basal area of all species. The strong selectivity for both species and size class means that the anthropogenic impacts are not uniform within the woody strata, leading to marked changes in community structure and floristics at a local scale.
- Full Text:
- Date Issued: 2006
- Authors: Pote, J , Shackleton, Charlie M , Cocks, Michelle L , Lubke, Roy
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6531 , http://hdl.handle.net/10962/d1005972
- Description: The Thicket Biome is the second smallest biome in South Africa, and is renowned for its high biodiversity. Yet, less than 5% of the biome is in formal conservation areas. Much of the currently intact thicket outside protected areas is threatened by land transformation to commercial agriculture or heavy use by rural communities. There is limited understanding of the ecological structure and function of thicket communities and their response to these human pressures. This paper reports on a study to characterize the woody communities in Valley Thicket and Thornveld surrounding a rural village. We also examined the demand and selection for specific woody species. There was a marked selection for key species for different uses, including fuelwood, construction timber, and cultural stacks. There was also strong selection for specific size classes of stem, especially those between 16–45 cm circumference. The density, biomass and species richness of woody species was reduced close to the village, and increased with distance away from human settlement. A similar trend was found for the basal area of preferred species, but not for the basal area of all species. The strong selectivity for both species and size class means that the anthropogenic impacts are not uniform within the woody strata, leading to marked changes in community structure and floristics at a local scale.
- Full Text:
- Date Issued: 2006
A proposed prioritization system for the management of invasive alien plants in South Africa
- Robertson, Mark P, Villet, Martin H, Fairbanks, Dean H K, Henderson, L, Higgins, Simon I, Hoffmann, John H, Le Maitre, David C, Palmer, Anthony R, Riggs, I, Shackleton, Charlie M, Zimmermann, Helmuth G
- Authors: Robertson, Mark P , Villet, Martin H , Fairbanks, Dean H K , Henderson, L , Higgins, Simon I , Hoffmann, John H , Le Maitre, David C , Palmer, Anthony R , Riggs, I , Shackleton, Charlie M , Zimmermann, Helmuth G
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6911 , http://hdl.handle.net/10962/d1011872
- Description: Every country has weed species whose presence conflicts in some way with human management objectives and needs. Resources for research and control are limited, so priority should be given to species that are the biggest problem. The prioritization system described in this article was designed to assess objectively research and control priorities of invasive alien plants at a national scale in South Africa. The evaluation consists of seventeen criteria, grouped into five modules, that assess invasiveness, spatial characteristics, potential impact, potential for control, and conflicts of interest for each plant species under consideration. Total prioritization scores, calculated from criterion and module scores, were used to assess a species' priority. Prioritization scores were calculated by combining independent assessments provided by several experts, thus increasing the reliability of the rankings. The total confidence score, a separate index, indicates the reliability and availability of data used to make an assessment. Candidate species for evaluation were identified and assessed by several experts using the prioritization system. The final ranking was made by combining two separate indices, the total prioritization score and the total confidence score. This approach integrates the plant's perceived priority with an index of data reliability. Of the 61 species assessed, those with the highest ranks (Lantana camara, Chromolaena odorata and Opuntia ficus-indica) had high prioritization and high confidence scores, and are thus of most concern. Those species with the lowest ranks, for example, Harrisia martinii, Opuntia spinulifera and Opuntia exaltata, had low prioritization scores and high confidence scores, and thus are of least concern. Our approach to ranking weeds offers several advantages over existing systems because it is designed for multiple assessors based on the Delphi decision-making technique, the criteria contribute equally to the total score, and the system can accommodate incomplete data on a species. Although the choice of criteria may be criticized and the system has certain limitations, it appears to have delivered credible results.
- Full Text:
- Date Issued: 2003
- Authors: Robertson, Mark P , Villet, Martin H , Fairbanks, Dean H K , Henderson, L , Higgins, Simon I , Hoffmann, John H , Le Maitre, David C , Palmer, Anthony R , Riggs, I , Shackleton, Charlie M , Zimmermann, Helmuth G
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6911 , http://hdl.handle.net/10962/d1011872
- Description: Every country has weed species whose presence conflicts in some way with human management objectives and needs. Resources for research and control are limited, so priority should be given to species that are the biggest problem. The prioritization system described in this article was designed to assess objectively research and control priorities of invasive alien plants at a national scale in South Africa. The evaluation consists of seventeen criteria, grouped into five modules, that assess invasiveness, spatial characteristics, potential impact, potential for control, and conflicts of interest for each plant species under consideration. Total prioritization scores, calculated from criterion and module scores, were used to assess a species' priority. Prioritization scores were calculated by combining independent assessments provided by several experts, thus increasing the reliability of the rankings. The total confidence score, a separate index, indicates the reliability and availability of data used to make an assessment. Candidate species for evaluation were identified and assessed by several experts using the prioritization system. The final ranking was made by combining two separate indices, the total prioritization score and the total confidence score. This approach integrates the plant's perceived priority with an index of data reliability. Of the 61 species assessed, those with the highest ranks (Lantana camara, Chromolaena odorata and Opuntia ficus-indica) had high prioritization and high confidence scores, and are thus of most concern. Those species with the lowest ranks, for example, Harrisia martinii, Opuntia spinulifera and Opuntia exaltata, had low prioritization scores and high confidence scores, and thus are of least concern. Our approach to ranking weeds offers several advantages over existing systems because it is designed for multiple assessors based on the Delphi decision-making technique, the criteria contribute equally to the total score, and the system can accommodate incomplete data on a species. Although the choice of criteria may be criticized and the system has certain limitations, it appears to have delivered credible results.
- Full Text:
- Date Issued: 2003