Modern supratidal microbialites fed by groundwater: functional drivers, value and trajectories
- Authors: Rishworth, Gavin M , Dodd, Carla , Perissinotto, Renzo , Bornman, Thomas G , Adams, Janine B , Anderson, Callum R , Cawthra, Hayley C , Dorrington, Hayley C , du Toit, Hendrik , Edworthy, Carla , Gibb, Ross-Lynne A , Human, Lucienne R D , Isemonger, Eric W , Lemley, David A , Miranda, Nelson A , Peer, Nasreen , Raw, Jacqueline L , Smith, Alan M , Steyn, Paul-Pierre , Strydom, Nadine A , Teske, Peter R , Welman, Peter R
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426008 , vital:72306 , xlink:href="https://doi.org/10.1016/j.earscirev.2020.103364"
- Description: Microbial mats were the dominant habitat type in shallow marine environments between the Palaeoarchean and Phanerozoic. Many of these (termed ‘microbialites’) calcified as they grew but such lithified mats are rare along modern coasts for reasons such as unsuitable water chemistry, destructive metazoan influences and competition with other reef-builders such as corals or macroalgae. Nonetheless, extant microbialites occur in unique coastal ecosystems such as the Exuma Cays, Bahamas or Lake Clifton and Hamelin Pool, Australia, where limitations such as calcium carbonate availability or destructive bioturbation are diminished. Along the coast of South Africa, extensive distributions of living microbialites (including layered stromatolites) have been discovered and described since the early 2000s. Unlike the Bahamian and Australian ecosystems, the South African microbialites form exclusively in the supratidal coastal zone at the convergence of emergent groundwater seepage. Similar systems were documented subsequently in southwestern Australia, Northern Ireland and the Scottish Hebrides, as recently as 2018, revealing that supratidal microbialites have a global distribution. This review uses the best-studied formations to contextualise formative drivers and processes of these supratidal ecosystems and highlight their geological, ecological and societal relevance.
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- Date Issued: 2020
Vocational education and training for African development: A literature review
- Authors: McGrath, Simon , Ramsarup, Presha , Zeelen, Jacques , Wedekind, Volker , Allais, Stephanie , Lotz-Sisitka, Heila , Monk, David , Openjuru, George , Russon, Jo-Anna
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182418 , vital:43828 , xlink:href="https://doi.org/10.1080/13636820.2019.1679969"
- Description: The SDGs mark the clearest global acceptance yet that the previous approach to development was unsustainable. In VET, UNESCO has responded by developing a clear account of how a transformed VET must be part of a transformative approach to development. It argues that credible, comprehensive skills systems can be built that can support individuals, communities, and organisations to generate and maintain enhanced and just livelihood opportunities. However, the major current theoretical approaches to VET are not up to this challenge. In the context of Africa, we seek to address this problem through a presentation of literatures that contribute to the theorisation of this new vision. They agree that the world is not made up of atomised individuals guided by a “hidden hand”. Rather, reality is heavily structured within political economies that have emerged out of contestations and compromises in specific historical and geographical spaces. Thus, labour markets and education and training systems have arisen, characterised by inequalities and exclusions. These specific forms profoundly influence individuals’ and communities’ views about the value of different forms of learning and working. However, they do not fully define what individuals dream, think and do. Rather, a transformed and transformative VET for Africa is possible.
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- Date Issued: 2020