scholarly journals Species composition, abundance and biomass of microphytoplankton in the KwaZulu-Natal Bight on the east coast of South Africa

2016 ◽  
Vol 38 (sup1) ◽  
pp. S139-S153 ◽  
Author(s):  
JS van der Molen ◽  
UM Scharler ◽  
D Muir
2010 ◽  
Vol 32 (2) ◽  
pp. 337-360 ◽  
Author(s):  
J C Coetzee ◽  
D Merkle ◽  
L Hutchings ◽  
C D van der Lingen ◽  
M van den Berg ◽  
...  

2016 ◽  
Vol 67 (11) ◽  
pp. 1750 ◽  
Author(s):  
Ander M. de Lecea ◽  
Rachel Cooper ◽  
Albertus J. Smit

The international literature highlights the importance of understanding the role and fate of terrestrial organic matter (OM) in the marine system, yet little is known about this on the oligotrophic east coast of South Africa. Within the Bight, three important processes make OM biologically available: (1) a topographically induced upwelling cell (north), (2) a Cyclonic Eddy (south), and (3) riverine input. We hypothesise that: (i) these OM sources differ substantially in their isotope ratios, and (ii) zooplankton at the inshore region has an isotope signature linked to localised fluvial fluxes. Particulate OM samples were collected at five locations along the Bight and in three main estuaries during austral summer and winter seasons in 2010 and subjected to isotopic and mixing model analysis. Riverine input played an important role in this ecosystem inshore during the wet season. Only marine OM played a role as a biological driver offshore and at all sites during the dry season. Although there were indications that the upwelling cell did occur, it was not confirmed as active in either season. The current study provides valuable insights into the Bight's biological functioning and principle insights into the fate of terrestrial organic carbon on the east coast of southern Africa.


2016 ◽  
Vol 50 (3) ◽  
pp. 580-590 ◽  
Author(s):  
Kimona Kisten ◽  
Roshila Moodley ◽  
Sreekantha B. Jonnalagadda

Author(s):  
Ivan G. Horak ◽  
Christiaan R. Boshoff ◽  
David V. Cooper ◽  
Christoper M. Foggin ◽  
Danny Govender ◽  
...  

The objectives of the study were to determine the species composition of ticks infesting white and black rhinoceroses in southern Africa as well as the conservation status of those tick species that prefer rhinos as hosts. Ticks were collected opportunistically from rhinos that had been immobilised for management purposes, and 447 white rhinoceroses (Ceratotherium simum) and 164 black rhinoceroses (Diceros bicornis) were sampled in South Africa, 61 black rhinos in Namibia, 18 white and 12 black rhinos in Zimbabwe, and 24 black rhinos in Zambia. Nineteen tick species were recovered, of which two species, Amblyomma rhinocerotis and Dermacentor rhinocerinus, prefer rhinos as hosts. A. rhinocerotis was collected only in the northeastern KwaZulu-Natal reserves of South Africa and is endangered, while D. rhinocerinus is present in these reserves as well as in the Kruger National Park and surrounding conservancies. Eight of the tick species collected from the rhinos are ornate, and seven species are regularly collected from cattle. The species present on rhinos in the eastern, moister reserves of South Africa were amongst others Amblyomma hebraeum, A. rhinocerotis, D. rhinocerinus, Rhipicephalus maculatus, Rhipicephalus simus and Rhipicephalus zumpti, while those on rhinos in the Karoo and the drier western regions, including Namibia, were the drought-tolerant species, Hyalomma glabrum, Hyalomma rufipes, Hyalomma truncatum and Rhipicephalus gertrudae. The species composition of ticks on rhinoceroses in Zambia differed markedly from those of the other southern African countries in that Amblyomma sparsum, Amblyomma tholloni and Amblyomma variegatum accounted for the majority of infestations.


Sign in / Sign up

Export Citation Format

Share Document