Hydrological development of the Eilandvlei system, southern Cape coast, South Africa during the Holocene

2016 ◽  
Vol 404 ◽  
pp. 183 ◽  
Author(s):  
K.L. Kirsten ◽  
T. Haberzettl ◽  
M. Wündsch ◽  
L.J. Quick ◽  
T. Kasper ◽  
...  
Keyword(s):  
South Africa ◽  
Cape Coast ◽  
The Holocene

scholarly journals Holocene sea level and environmental change at the southern Cape – an 8.5 kyr multi-proxy paleoclimate record from Lake Voëlvlei, South Africa

2021 ◽  
Vol 17 (4) ◽  
pp. 1567-1586
Author(s):  
Paul Strobel ◽  
Marcel Bliedtner ◽  
Andrew S. Carr ◽  
Peter Frenzel ◽  
Björn Klaes ◽  
...  
Keyword(s):  
South Africa ◽  
Sea Level ◽  
Coastal Wetland ◽  
Environmental Changes ◽  
Late Quaternary ◽  
Regional Studies ◽  
Sea Level Changes ◽  
Cape Coast ◽  
The Holocene ◽  
Elemental Analyses

Abstract. South Africa is a key region to reconstruct and understand past changes in atmospheric circulation, i.e. temperate westerlies and tropical easterlies. However, due to the scarcity of natural archives, South Africa's environmental evolution during the late Quaternary remains highly debated. Many available sediment archives are peri-coastal lakes and wetlands; however, the paleoenvironmental signals in these archives are often overprinted by sea-level changes during the Holocene. This study presents a new record from the coastal wetland Voëlvlei, which is situated in the year-round rainfall zone of South Africa on the southern Cape coast. It presents an ideal sedimentary archive to investigate both sea level and environmental changes. A 13 m long sediment core was retrieved and analysed using a multi-proxy approach. The chronology reveals a basal age of 8440 +200/-250 cal BP. Paleoecological and elemental analyses indicate marine incursions from ca. 8440 to ca. 7000 cal BP with a salinity optimum occurring at 7090 +170/-200 cal BP. At ca. 6000 cal BP, the basin of Voëlvlei was in-filled with sediment resulting in an intermittent (sporadically desiccated) freshwater lake similar to present. In contrast to previous investigations which used indirect proxies for hydrological reconstructions, here we apply a combined biomarker–sedimentological approach that allows the potential identification of precipitation sources, in combination with relative estimates of moisture availability. Increasing moisture is observed throughout the record starting from 8440 +200/-250 cal BP with contributions from both westerlies and easterlies from ca. 8440 to ca. 7070 cal BP. Westerly-derived rainfall dominates from ca. 7070 to ca. 6420 cal BP followed by a distinct shift to an easterly dominance at ca. 6420 cal BP. An overall trend to westerly dominance lasting until ca. 2060 cal BP is followed by a trend towards an easterly dominance to the present, but both phases show several intense, short-term variations. These variations are also evident in other regional studies, highlighting that the source and seasonality of precipitation has varied distinctly on the southern Cape during the Holocene. Comparison of the Voëlvlei record with other regional studies suggests a coherent trend in the overall moisture evolution along the southern Cape coast during the past 8500 years.

A multiproxy study of the ocean-atmospheric forcing and the impact of sea-level changes on the southern Cape coast, South Africa during the Holocene

2018 ◽  
Vol 496 ◽  
pp. 282-291 ◽  
Author(s):  
Kelly L. Kirsten ◽  
Torsten Haberzettl ◽  
Michael Wündsch ◽  
Peter Frenzel ◽  
Stephanie Meschner ◽  
...  
Keyword(s):  
South Africa ◽  
Sea Level ◽  
Atmospheric Forcing ◽  
Sea Level Changes ◽  
Cape Coast ◽  
The Holocene ◽  
The Impact

Cranial crassicaudiasis in two coastal dolphin species from South Africa is predominantly a disease of immature individuals

2020 ◽  
Vol 139 ◽  
pp. 93-102 ◽  
Author(s):  
MF Van Bressem ◽  
P Duignan ◽  
JA Raga ◽  
K Van Waerebeek ◽  
N Fraijia-Fernández ◽  
...  
Keyword(s):  
South Africa ◽  
Bone Development ◽  
Bottlenose Dolphins ◽  
Fatal Outcome ◽  
Population Level ◽  
Cape Coast ◽  
Osteolytic Lesions ◽  
Immune Mediated ◽  
Significant Difference ◽  
The Difference

Crassicauda spp. (Nematoda) infest the cranial sinuses of several odontocetes, causing diagnostic trabecular osteolytic lesions. We examined skulls of 77 Indian Ocean humpback dolphins Sousa plumbea and 69 Indo-Pacific bottlenose dolphins Tursiops aduncus, caught in bather-protecting nets off KwaZulu-Natal (KZN) from 1970-2017, and skulls of 6 S. plumbea stranded along the southern Cape coast in South Africa from 1963-2002. Prevalence of cranial crassicaudiasis was evaluated according to sex and cranial maturity. Overall, prevalence in S. plumbea and T. aduncus taken off KZN was 13 and 31.9%, respectively. Parasitosis variably affected 1 or more cranial bones (frontal, pterygoid, maxillary and sphenoid). No significant difference was found by gender for either species, allowing sexes to be pooled. However, there was a significant difference in lesion prevalence by age, with immature T. aduncus 4.6 times more likely affected than adults, while for S. plumbea, the difference was 6.5-fold. As severe osteolytic lesions are unlikely to heal without trace, we propose that infection is more likely to have a fatal outcome for immature dolphins, possibly because of incomplete bone development, lower immune competence in clearing parasites or an over-exuberant inflammatory response in concert with parasitic enzymatic erosion. Cranial osteolysis was not observed in mature males (18 S. plumbea, 21 T. aduncus), suggesting potential cohort-linked immune-mediated resistance to infestation. Crassicauda spp. may play a role in the natural mortality of S. plumbea and T. aduncus, but the pathogenesis and population level impact remain unknown.

scholarly journals Pleistocene golden mole and sand-swimming trace fossils from the Cape coast of South Africa

2021 ◽  
pp. 1-18
Author(s):  
Martin G. Lockley ◽  
Charles W. Helm ◽  
Hayley C. Cawthra ◽  
Jan C. De Vynck ◽  
Michael R. Perrin
Keyword(s):  
South Africa ◽  
Trace Fossils ◽  
Trace Fossil ◽  
South Coast ◽  
Environmental Reconstruction ◽  
Cape Coast ◽  
Southeast Coast ◽  
Show Evidence ◽  
Golden Mole ◽  
Body Fossil

Abstract More than 250 Pleistocene vertebrate trace fossil sites have been identified on the Cape south coast of South Africa in aeolianites and cemented foreshore deposits. These discoveries, representing the epifaunal tracks of animals that moved over these sand substrates, complement traditional body fossil studies, and contribute to palaeo-environmental reconstruction. Not described in detail until now, but also important faunal components, are the infaunal traces of animals that moved within these sandy substrates. Six golden mole burrow trace sites (Family Chrysochloridae) have been identified on the Cape south coast. In addition, three sites, including one on the Cape southeast coast, have been identified that show evidence of sand-swimming, probably by a golden mole with a means of locomotion similar to that of the extant Eremitalpa genus. Such traces have not been described in detail in the global ichnology record, and merit the erection of a new ichnogenus Natatorichnus, with two ichnospecies, N. subarenosa ichnosp. nov and N. sulcatus ichnosp. nov. Care is required in the identification of such traces, and the orientation of the trace fossil surface needs to be determined, to avoid confusion with hatchling turtle tracks. Substantial regional Pleistocene dune environments are inferred from these sand-swimming traces.

New taxa of Babiana (Iridaceae: Crocoideae) from coastal Western Cape, South Africa

Bothalia ◽  
2010 ◽  
Vol 40 (1) ◽  
pp. 47-53 ◽  
Author(s):  
P. Goldblatt ◽  
J. C. Manning
Keyword(s):  
South Africa ◽  
New Species ◽  
New Taxa ◽  
Field Work ◽  
Western Cape ◽  
Cape Coast ◽  
Perianth Tube ◽  
Pale Green ◽  
A New Species

Discovery of populations south of Elandshaai of a small-flowered plant closely allied to Babiana ringens led to a critical re-evaluation of this sunbird-pollinated Western Cape species. We conclude that these populations represent a new species, B. avicularis, recognized by long, arching, subterete leaves, and flowers with the lower part of the perianth tube sigmoid and ± 4 mm long, a dorsal tepal 15-18 mm long, pale green lower tepals directed forward, and a style dividing below the bases of the anthers. In addition, the southern coastal populations of B. ringens merit recognition as a separate subsp. australis, recognized by the smaller flower, filaments not reaching the apex of the dorsal tepal and the style dividing at or below the bases of the anthers. Field work along the Western Cape coast also resulted in the discovery of a new species, B. teretifolia, allied to the distinctive B. brachystachys but differing from that species in the linear, spreading, twisted tepals, filaments 12 mm long, white anthers 5.5-6.0 mm long, and the style dividing opposite the anther tips, with branches ± 5 mm long and notched at the tips.

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