No abstract
Abstract:The Swartland region in the Western Cape of South Africa is situated in a Mediterranean climate zone, aff ected by large gullies that are widespread in occurrence on commercial farms. Despite gully erosion being recognized as a major land degradation process, especially in Mediterranean climates, these large gully scars in the Swartland are believed to be inactive remnants of the past. Due to this belief, gully erosion research in the Swartland is a topic that has long been ignored.To address this research shortfall, a fi eld-based case study of a classic, discontinuous gully system in the Swartland was done.Sediment movement was measured at hillslope scale and discussed in the context of rainfall data and fi eld observations of gully activity. The results showed that the gully system was an active sediment source, but also a conduit for sediment from hillslopes. Notably, ploughed contour banks, a measure introduced to curb gully erosion, are causing the expansion of the gully network, in addition to delivering sediment from hillslope sources to the gully system. Vegetation cover was found to reduce gully erosion temporally by up to 91.6% during the case study period. This case study illustrates that large gully channels are not mere relics of the past, but complex erosive systems that require further fi eld-based investigations to develop an understanding of the dynamics involved.Resumo: A região de Swartland, localizada no Cabo Ocidental na África do Sul, situa-se numa zona de clima mediterrâ-neo, afectada por grandes ravinas que ocorrem com frequência em quintas comerciais. Apesar da erosão das ravinas ser reconhecida como um processo signifi cativo de degradação do solo, em especial nos climas mediterrâneos, acredita-se que estas grandes cicatrizes em Swartland são vestígios inactivos do passado. Devido a esta crença, a pesquisa sobre a erosão das ravinas de Swartland é um tema há muito ignorado. De modo a abordar esta carência de investigação, foi realizado um caso-de-estudo de um sistema clássico e descontínuo de ravinas em Swartland. O movimento dos sedimentos foi medido na escala de vertente e discutido no contexto de dados de precipitação e observações de campo da actividade das ravinas. Os resultados mostraram que o sistema de ravinas é uma fonte activa de sedimentos, como também um veículo para os sedimentos das vertentes. Notavelmente, os bancos de contorno arados, medida introduzida para controlar a erosão das ravinas, estão a causar a expansão desta rede, além de adicionarem sedimentos das vertentes aos sistemas de ravinas. A cobertura vegetal reduziu a erosão temporariamente até 91,6% durante o período do caso-de-estudo. Este demonstrou que as grandes ravinas não são apenas relíquias do passado, mas sim sistemas complexos de erosão que necessitam de mais investigação de campo para se desenvolver uma compreensão das dinâmicas envolvidas.
Foreign relations are the main preoccupation of South African president, Thabo Mbeki. His role perception is dominated by a mission to improve the plight of Africa, and second to that, to act as the Third World's überdiplomat. Under his administration, South Africa's foreign policy has become almost an adjunct of his more holistic diplomatic pursuits. The New Partnership for Africa's Development (NEPAD) is the magnum opus of Mbeki's foreign policy, and the success or failure of this grand design for an African renaissance will determine his legacy and make or break his leadership in South Africa and in the rest of Africa. The success of his NEPAD diplomacy is a daunting task, requiring the support of his African peers, his South African constituency, and the leadership of the developed nations of the world. Dealing with these diverse elements, Mbeki's policy‐making oscillates between realism and idealism, and between ideology and interests, giving the impression of a style of a prudent bureaucrat rather than that of a single‐minded reformer. In the end, his diplomacy seems to founder because it fails to satisfy the contradictory demands of any of these three constituencies. However, even if NEPAD should fail as a project, its role could be that of a harbinger of a new political and economic era in Africa and the movement away from post‐colonial orthodoxy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.