Allelopathic effects of Lantana camara on indigenous forest species in South Africa
- Ruwanza, Sheunesu, Shackleton, Charlie M
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182296 , vital:43818 , xlink:href="http://www.allelopathyjournal.org/?"
- Description: Lantana camara, is an invasive plant in South Africa and greatly influences the forest spp. In greenhouse, we evaluated the allelopathic effects of aqueous extracts of L. camara leaf, stem and root on 5-test species, (3-forest species viz., Acacia natalitia, Kiggalaria africana and Searsia crenata and 2-crops: Solanum lycopersicum and Lactuca sativa). Potential allelopathic compounds present in L. camara leaf, stem and root aqueous extracts were identified using gas chromatography mass spectrometry (GC-MS). The leaf, stem and root aqueous extracts of L. camara reduced the seed germination and seedling growth of all test species showing that L. camara aqueous extracts were deleterious to all test species. We identified 92 major volatile organic components in L. camara aqueous extracts. These compounds had the potential to inhibit the germination and seedling growth of test crops. The leaf, stem and root aqueous extracts of L. camara contained the allelopathic compounds that inhibited the germination and seedling growth of indigenous forest species and crop species.
- Full Text:
- Date Issued: 2016
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182296 , vital:43818 , xlink:href="http://www.allelopathyjournal.org/?"
- Description: Lantana camara, is an invasive plant in South Africa and greatly influences the forest spp. In greenhouse, we evaluated the allelopathic effects of aqueous extracts of L. camara leaf, stem and root on 5-test species, (3-forest species viz., Acacia natalitia, Kiggalaria africana and Searsia crenata and 2-crops: Solanum lycopersicum and Lactuca sativa). Potential allelopathic compounds present in L. camara leaf, stem and root aqueous extracts were identified using gas chromatography mass spectrometry (GC-MS). The leaf, stem and root aqueous extracts of L. camara reduced the seed germination and seedling growth of all test species showing that L. camara aqueous extracts were deleterious to all test species. We identified 92 major volatile organic components in L. camara aqueous extracts. These compounds had the potential to inhibit the germination and seedling growth of test crops. The leaf, stem and root aqueous extracts of L. camara contained the allelopathic compounds that inhibited the germination and seedling growth of indigenous forest species and crop species.
- Full Text:
- Date Issued: 2016
Effects of the invasive shrub, Lantana camara, on soil properties in the Eastern Cape, South Africa
- Ruwanza, Sheunesu, Shackleton, Charlie M
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180459 , vital:43391 , xlink:href="https://doi.org/10.1111/wbm.12094"
- Description: Lantana camara L. is an invasive alien shrub of worldwide significance due to its impacts on biodiversity. It can alter the soil properties of invaded ecosystems and, as a result, affect management outcomes. However, knowledge on the impacts of L. camara on soil properties is scanty, especially in South Africa, despite the pervasive presence of the plant in the country. In this comparative study, the soils underneath L. camara were assessed in order to determine if they had different properties (soil physico-chemical properties, penetration resistance, infiltration, hydraulic conductivity and water repellency) in comparison to the soils in adjacent natural sites in the Eastern Cape, South Africa. Soil samples were collected from the top soil beneath the canopy of both L. camara-invaded and adjacent natural sites in five different locations over three summer months. The soils that were collected from underneath L. camara had a significantly higher total C, total P, gravimetric soil moisture (in November and December) and were repellent, compared to the soils in the adjacent natural sites. Soil penetration resistance was significantly higher in the natural sites than in the L. camara-invaded sites. The soil hydraulic conductivity, soil infiltration rate, soil pH, exchangeable cations and total N showed no significant difference between the invaded and the natural sites. It appears that the soils underneath L. camara have a high total C and total P, soil moisture and are repellent, thus influencing nutrient cycling, potentially making the soil properties underneath it ideal for its own growth. This could contribute to the success of L. camara as an invasive species.
- Full Text:
- Date Issued: 2016
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180459 , vital:43391 , xlink:href="https://doi.org/10.1111/wbm.12094"
- Description: Lantana camara L. is an invasive alien shrub of worldwide significance due to its impacts on biodiversity. It can alter the soil properties of invaded ecosystems and, as a result, affect management outcomes. However, knowledge on the impacts of L. camara on soil properties is scanty, especially in South Africa, despite the pervasive presence of the plant in the country. In this comparative study, the soils underneath L. camara were assessed in order to determine if they had different properties (soil physico-chemical properties, penetration resistance, infiltration, hydraulic conductivity and water repellency) in comparison to the soils in adjacent natural sites in the Eastern Cape, South Africa. Soil samples were collected from the top soil beneath the canopy of both L. camara-invaded and adjacent natural sites in five different locations over three summer months. The soils that were collected from underneath L. camara had a significantly higher total C, total P, gravimetric soil moisture (in November and December) and were repellent, compared to the soils in the adjacent natural sites. Soil penetration resistance was significantly higher in the natural sites than in the L. camara-invaded sites. The soil hydraulic conductivity, soil infiltration rate, soil pH, exchangeable cations and total N showed no significant difference between the invaded and the natural sites. It appears that the soils underneath L. camara have a high total C and total P, soil moisture and are repellent, thus influencing nutrient cycling, potentially making the soil properties underneath it ideal for its own growth. This could contribute to the success of L. camara as an invasive species.
- Full Text:
- Date Issued: 2016
Incorporation of environmental issues in South Africa’s municipal Integrated Development Plans
- Ruwanza, Sheunesu, Shackleton, Charlie M
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180481 , vital:43393 , xlink:href="https://doi.org/10.1080/13504509.2015.1062161"
- Description: The transition to full democracy in South Africa in 1994 saw local government becoming the focal point for dealing with socio-economic development needs of communities. The Integrated Development Plan (IDP) has been used as the tool for guiding local development objectives, balanced against environmental demands within a sustainable development paradigm. Here we examine the extent to which this is being achieved through an analysis of IDPs from 35 different municipalities at three scales. We test the hypothesis that the metropolitan municipalities are better at mainstreaming environmental issues into their IDPs than local and district municipalities. Results indicate that mainstreaming environmental issues in IDPs is still low. The hypothesis that metropoles are better at mainstreaming environmental issues than district and local municipalities was not accepted since there were no significant differences between municipalities. There was low relative budget allocations and inclusion of vision and mission statements that mainstream environmental issues in all municipalities. For mainstreaming of environmental issues to be effective in IDPs, both proactive approaches and multi-faceted bottom-up and top-down approaches are suggested.
- Full Text:
- Date Issued: 2016
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180481 , vital:43393 , xlink:href="https://doi.org/10.1080/13504509.2015.1062161"
- Description: The transition to full democracy in South Africa in 1994 saw local government becoming the focal point for dealing with socio-economic development needs of communities. The Integrated Development Plan (IDP) has been used as the tool for guiding local development objectives, balanced against environmental demands within a sustainable development paradigm. Here we examine the extent to which this is being achieved through an analysis of IDPs from 35 different municipalities at three scales. We test the hypothesis that the metropolitan municipalities are better at mainstreaming environmental issues into their IDPs than local and district municipalities. Results indicate that mainstreaming environmental issues in IDPs is still low. The hypothesis that metropoles are better at mainstreaming environmental issues than district and local municipalities was not accepted since there were no significant differences between municipalities. There was low relative budget allocations and inclusion of vision and mission statements that mainstream environmental issues in all municipalities. For mainstreaming of environmental issues to be effective in IDPs, both proactive approaches and multi-faceted bottom-up and top-down approaches are suggested.
- Full Text:
- Date Issued: 2016
Unpacking Pandora’s box: Understanding and categorising ecosystem disservices for environmental management and human wellbeing
- Shackleton, Charlie M, Ruwanza, Sheunesu, Sinasson Sanni, Gisele, Bennett, S, De Lacy, Peter, Modipa, Rebone D, Mtati, Nosiseko, Sachikonye, Mwazvita T B, Thondhlana, Gladman
- Authors: Shackleton, Charlie M , Ruwanza, Sheunesu , Sinasson Sanni, Gisele , Bennett, S , De Lacy, Peter , Modipa, Rebone D , Mtati, Nosiseko , Sachikonye, Mwazvita T B , Thondhlana, Gladman
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182113 , vital:43801 , xlink:href="https://doi.org/10.1007/s10021-015-9952-z"
- Description: Research into the benefits that ecosystems contribute to human wellbeing has multiplied over the last few years following from the seminal contributions of the international Millennium Ecosystem Assessment. In comparison, the fact that some ecosystem goods and services undermine or harm human wellbeing has been seriously overlooked. These negative impacts have become known as ecosystem disservices. The neglect of ecosystem disservices is problematic because investments into the management or reduction of ecosystem disservices may yield better outcomes for human wellbeing, or at a lower investment, than management of ecosystem services. Additionally, management to optimise specific ecosystem services may simultaneously exacerbate associated disservices. We posit that one reason for the neglect of ecosystem disservices from the discourse and policy debates around ecosystems and human wellbeing is because there is no widely accepted definition or typology of ecosystem disservices. Here, we briefly examine current understandings of the term ecosystem disservices and offer a definition and a working typology to help generate debate, policy and management options around ecosystem disservices. We differentiate ecosystem disservices from natural hazards and social hazards, consider some of their inherent properties and then classify them into six categories. A variety of examples are used to illustrate the different types of, and management strategies to, ecosystem disservices.
- Full Text:
- Date Issued: 2016
- Authors: Shackleton, Charlie M , Ruwanza, Sheunesu , Sinasson Sanni, Gisele , Bennett, S , De Lacy, Peter , Modipa, Rebone D , Mtati, Nosiseko , Sachikonye, Mwazvita T B , Thondhlana, Gladman
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182113 , vital:43801 , xlink:href="https://doi.org/10.1007/s10021-015-9952-z"
- Description: Research into the benefits that ecosystems contribute to human wellbeing has multiplied over the last few years following from the seminal contributions of the international Millennium Ecosystem Assessment. In comparison, the fact that some ecosystem goods and services undermine or harm human wellbeing has been seriously overlooked. These negative impacts have become known as ecosystem disservices. The neglect of ecosystem disservices is problematic because investments into the management or reduction of ecosystem disservices may yield better outcomes for human wellbeing, or at a lower investment, than management of ecosystem services. Additionally, management to optimise specific ecosystem services may simultaneously exacerbate associated disservices. We posit that one reason for the neglect of ecosystem disservices from the discourse and policy debates around ecosystems and human wellbeing is because there is no widely accepted definition or typology of ecosystem disservices. Here, we briefly examine current understandings of the term ecosystem disservices and offer a definition and a working typology to help generate debate, policy and management options around ecosystem disservices. We differentiate ecosystem disservices from natural hazards and social hazards, consider some of their inherent properties and then classify them into six categories. A variety of examples are used to illustrate the different types of, and management strategies to, ecosystem disservices.
- Full Text:
- Date Issued: 2016
- «
- ‹
- 1
- ›
- »