24 research outputs found
Beach ridge sets reflect the late Holocene evolution of the St Lucia estuarine lake system, South Africa
Geomorphology of the upper Mkhomazi River basin, KwaZulu-Natal, South Africa, with emphasis on late Pleistocene colluvial deposits
We present a 1:50 000 scale geomorphological map of the upper Mkhomazi River basin, located in the foothills of the Drakensberg mountains in KwaZulu-Natal Province, South Africa. The sub-horizontal strata of the Permo-Triassic Beaufort Group forms plateau interfluves with a concave valley slope morphology. Locally, thick sequences of late Pleistocene colluvial deposits and associated buried paleosols (Masotcheni Formation) infill first-order tributary stream valleys and extend across the adjacent lower slopes. Surface runoff processes preferentially incise into the poorly consolidated, highly erodible sediments causing severe gully erosion that is responsible for widespread land degradation and desertification phenomena. The main purpose of this work is to derive a geomorphological map of the study area focussing on the erosional landforms to understand their spatial distribution and their relation to the colluvial deposits. Finally, a local and regional stratigraphic correlation of colluvial deposits and associated buried palaeosol profiles is proposed
Drowning in data, thirsty for information and starved for understanding: A biodiversity information hub for cooperative environmental monitoring in South Africa
The world is firmly cemented in a notitian age (Latin: notitia, meaning data) – drowning in data, yet thirsty for information and the synthesis of knowledge into understanding. As concerns over biodiversity declines escalate, the volume, diversity and speed at which new environmental and ecological data are generated has increased exponentially. Data availability primes the research and discovery engine driving biodiversity conservation. South Africa (SA) is poised to become a world leader in biodiversity conservation. However, continent-wide resource limitations hamper the establishment of inclusive technologies and robust platforms and tools for biodiversity informatics. In this perspectives piece, we bring together the opinions of 37 co-authors from 20 different departments, across 10 SA universities, 7 national and provincial conservation research agencies, and various institutes and private conservation, research and management bodies, to develop a way forward for biodiversity informatics in SA. We propose the development of a SA Biodiversity Informatics Hub and describe the essential components necessary for its design, implementation and sustainability. We emphasise the importance of developing a culture of cooperation, collaboration and interoperability among custodians of biodiversity data to establish operational workflows for data synthesis. However, our biggest challenges are misgivings around data sharing and multidisciplinary collaboration
Drowning in data, thirsty for information and starved for understanding: A biodiversity information hub for cooperative environmental monitoring in South Africa
The world is firmly cemented in a notitian age (Latin: notitia, meaning data) – drowning in data, yet thirsty for information and the synthesis of knowledge into understanding. As concerns over biodiversity declines escalate, the volume, diversity and speed at which new environmental and ecological data are generated has increased exponentially. Data availability primes the research and discovery engine driving biodiversity conservation. South Africa (SA) is poised to become a world leader in biodiversity conservation. However, continent-wide resource limitations hamper the establishment of inclusive technologies and robust platforms and tools for biodiversity informatics. In this perspectives piece, we bring together the opinions of 37 co-authors from 20 different departments, across 10 SA universities, 7 national and provincial conservation research agencies, and various institutes and private conservation, research and management bodies, to develop a way forward for biodiversity informatics in SA. We propose the development of a SA Biodiversity Informatics Hub and describe the essential components necessary for its design, implementation and sustainability. We emphasise the importance of developing a culture of cooperation, collaboration and interoperability among custodians of biodiversity data to establish operational workflows for data synthesis. However, our biggest challenges are misgivings around data sharing and multidisciplinary collaboration
Colluvial deposits and slope instability
Slope instability results from the interplay between tectonic uplift, climatecontrolled weathering, and slope form (relief). Sediments accumulate as colluvium on footslopes when under the influence of gravity, fluvial processes and mass movements, and may be affected by pedogenesis, ecosystem change and human activity. This chapter shows that colluvial form and stratigraphy cannot be uncritically assigned to particular late Pleistocene and Holocene climatic periods, because of the feedbacks associated with weathering rate, vegetation responses to climate, and slope angle. Moreover, land surface instability and colluvial formation/incision is taking place due to contemporary environmental degradation, closely related to overgrazing.</p
Evaluation of Gully Erosion Susceptibility Using a Maximum Entropy Model in the Upper Mkhomazi River Basin in South Africa
Soil erosion is one of the most challenging environmental issues in the world, causing unsustainable soil loss every year. In South Africa, several episodes of gully erosion have been documented and clearly linked to the presence of Quaternary colluvial deposits on the Drakensberg Mountain footslopes. The aim of this study was to identify and assess the triggering factors of gully erosion in the upper Mkhomazi River basin in KwaZulu-Natal, South Africa. We compiled a gully inventory map and applied remote sensing techniques as well as field surveys to validate the gully inventory. The gullies were subdivided into slope gullies and fluvial gullies. We derived susceptibility maps based on the spatial distribution of gully types to assess the most important driving factors. A stochastic modeling approach (MaxEnt) was applied, and the results showed two susceptibility maps within the spatial distribution of the gully erosion probability. To validate the MaxEnt model results, a subset of the existing inventory map was used. Additionally, by using areas with high susceptibilities, we were able to delineate previously unmapped colluvial deposits in the region. This predictive mapping tool can be applied to provide a theoretical basis for highlighting erosion-sensitive substrates to reduce the risk of expanding gully erosion
Archaeological Reconnaissance for Middle Stone Age Sites Along the Pondoland Coast, South Africa
This paper summarizes the results of a recent survey of the South African “Wild Coast” in Pondoland, Eastern
Cape Province. The purpose of the survey was to locate and to describe coastal caves and rock shelters that may
contain Early and Middle Stone Age archaeological deposits for future study. The study is part of a much larger
research design to understand three basic and interlinked paleoanthropological questions: When did coastal intertidal
foraging develop? How did it develop? What role did coastal intertidal foods have on the evolution and
survival of early modern humans?
Here, we provide the full results of our multi-disciplinary survey. We describe the archaeology, geology, marine,
and terrestrial fauna from four near-coastal rock shelters and one coastal open-air site that we intend to test
in the future. We also provide the first direct ages of the coastal red sands that contain in situ Early Stone Age
Acheulian and early Middle Stone Age flaked stone tools. These optically stimulated luminescence ages show that
humans have inhabited Pondoland for over 300,000 years, predating the currently known origins of the modern
human lineage and systematic coastal foraging. We also describe the first dated paleoenvironmental sequences
for Pondoland, which suggest a shift from C3 to C4 vegetation during the middle Holocene. Lastly, we provide
comprehensive notes on all sites in Supplementary Online Materials to benefit future studies across the region and
document an area that has seen very limited archaeological researchPart of the phytolith analysis was supported by
the Ministerio de Ciencia e Innovación (HAR2010-15967 to
Albert). The field survey was funded by a grant from the
National Geographic Society / Waitt Foundation (W160-11
to Fisher)Peer reviewe
Neutron radiotherapy in South Africa: Neutron radiotherapy: Society comments
This correspondence is in response to the article:
Abratt RP. The fast neutron therapy programme for patients in South Africa should come to an end. S Afr Med J 2012;102(2):58. Other correspondence in this series: Neutron radiotherapy: a different perspective. Neutron radiotherapy should continue. S Afr Med J 2012;102(5):269-270; Neutron radiotherapy, Abratt reply. S Afr Med J 2012;102(5):270-217; Neutron radiotherapy: Abratt supported. S Afr Med J 2012;102(5):271