Diverse pollination systems of the twin-spurred orchid genus Satyrium in African grasslands
- Johnson, S.D, Peter, C.I, Ellis, A.G, Boberg, E, Botes, C, Van der Niet, T
- Authors: Johnson, S.D , Peter, C.I , Ellis, A.G , Boberg, E , Botes, C , Van der Niet, T
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6558 , http://hdl.handle.net/10962/d1006025 , http://dx.doi.org/10.1007/s00606-010-0411-1
- Description: The large terrestrial orchid genus Satyrium underwent evolutionary radiations in the Cape floral region and the grasslands of southern and eastern Africa. These radiations were accompanied by tremendous diversification of the unusual twin-spurred flowers that characterize the genus, but pollination data required to interpret these patterns of floral evolution have been lacking for grassland species in the genus. Here we document pollinators, nectar properties, and levels of pollination success for 11 grassland Satyrium species in southern and south-central Africa. Pollinators of these species include bees, beetles, butterflies, hawkmoths, noctuid moths, long-proboscid flies, and sunbirds. Most species appear to be specialized for pollination by one functional pollinator group. Long-proboscid fly pollination systems are reported for the first time in Satyrium (in S. macrophyllum and a high-altitude form of S. neglectum). Floral morphology, especially spur length and rostellum structure, differs markedly among plants with different pollinators, while nectar volume, concentration, and sugar composition are fairly uniform across species. Most taxa exhibited high levels of pollination success (>50% of flowers pollinated), a trend that can be attributed to the presence of nectar in the twin spurs.
- Full Text:
- Date Issued: 2011
- Authors: Johnson, S.D , Peter, C.I , Ellis, A.G , Boberg, E , Botes, C , Van der Niet, T
- Date: 2011
- Language: English
- Type: Article
- Identifier: vital:6558 , http://hdl.handle.net/10962/d1006025 , http://dx.doi.org/10.1007/s00606-010-0411-1
- Description: The large terrestrial orchid genus Satyrium underwent evolutionary radiations in the Cape floral region and the grasslands of southern and eastern Africa. These radiations were accompanied by tremendous diversification of the unusual twin-spurred flowers that characterize the genus, but pollination data required to interpret these patterns of floral evolution have been lacking for grassland species in the genus. Here we document pollinators, nectar properties, and levels of pollination success for 11 grassland Satyrium species in southern and south-central Africa. Pollinators of these species include bees, beetles, butterflies, hawkmoths, noctuid moths, long-proboscid flies, and sunbirds. Most species appear to be specialized for pollination by one functional pollinator group. Long-proboscid fly pollination systems are reported for the first time in Satyrium (in S. macrophyllum and a high-altitude form of S. neglectum). Floral morphology, especially spur length and rostellum structure, differs markedly among plants with different pollinators, while nectar volume, concentration, and sugar composition are fairly uniform across species. Most taxa exhibited high levels of pollination success (>50% of flowers pollinated), a trend that can be attributed to the presence of nectar in the twin spurs.
- Full Text:
- Date Issued: 2011
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
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
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