Observations on the relation between phytoplankton diversity and environmental factors in the Vaal River at Balkfontein, South Africa

Late language emergence (LLE) may result from genetic and environmental factors. Little is known about environmental factors in LLE in South Africa. The study describes the nature of differences in language functioning between toddlers with LLE and without LLE, and which factors were associated with LLE in a middle-income area in South Africa. Toddlers, aged 24 to 36 months with LLE ( n = 20) were matched with a control group (CG, n = 21) for household income, age, gender, maternal education, and parental employment. The research group (RG) showed moderate delays in expressive and receptive language, and play skills, while the controls exhibited no delay. Significant differences in early feeding history and multilingual exposure were found between the groups. As far as known, it is the first study utilizing a South African middle-income sample indicating that multilingual exposure may play a role in LLE. The study focuses the attention on environmental factors which are potentially modifiable in LLE.

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Alluvial Terraces of the Lower Vaal River, South Africa: A Reappraisal and Reinvestigation: A Reply

The Journal of Geology ◽

10.1086/628014 ◽

1974 ◽

Vol 82 (5) ◽

pp. 665-667 ◽

Cited By ~ 1

Author(s):

David M. Helgren ◽

Karl W. Butzer

Keyword(s):

South Africa ◽

Vaal River ◽

Alluvial Terraces

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Inter basin water transfers

Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie ◽

10.4102/satnt.v4i3.1036 ◽

1985 ◽

Vol 4 (3) ◽

pp. 93-98 ◽

Cited By ~ 1

Author(s):

T. P. C. Van Robbroeck

Keyword(s):

South Africa ◽

Economic Development ◽

Water Resources ◽

National Interest ◽

Transfer Scheme ◽

Water Transfers ◽

Vaal River ◽

Run Off ◽

Basin Water ◽

Reserve Storage

Most economic development in South Africa has taken place on the dry plateau of the interior following the discovery of minerals. The much smaller wetter parts get most of the run-off and have generally limited possibilities for advantageous use of their water resources. Consequently, it is logical to transfer water between basins with a surplus to ones experiencing shortages. There is a body of opinion that such transfers should be stopped in the interest of the decentralistion policy, but such action is not considered in the national interest. The intricate system of inter-basin transfer from the Komati, the Usutu and the Vaal River to supply the Eastern Transvaal coalfields is described. This system has shown its flexibility during the recent drought. The most important inter-basin transfer scheme is the Tugeia- Vaal Project which is described in broad terms. The advantages of the principle of reserve storage and of co-operation with Escom are dealt with. Possible further projects to augment the Vaal River supplies are mentioned. Other inter-basin transfer schemes implemented by the Department of Water Affairs such as the Orange River Project, the Riviersonderend-Berg River Project and others of lesser importance are dealth with.

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Paradiplozoon vaalense n. sp. (Monogenea: Diplozoidae) from the gills of moggel, Labeo umbratus (Smith, 1841), in the Vaal River System, South Africa

Journal of Helminthology ◽

10.1017/s0022149x1300059x ◽

2013 ◽

Vol 89 (1) ◽

pp. 58-67 ◽

Cited By ~ 16

Author(s):

Q.M. Dos Santos ◽

B. Jansen van Vuuren ◽

A. Avenant-Oldewage

Keyword(s):

South Africa ◽

Sequence Data ◽

Light And Electron Microscopy ◽

River System ◽

Ribosomal Gene ◽

Its2 Region ◽

Genetic Characteristics ◽

Vaal River ◽

Vaal Dam ◽

Second Internal Transcribed Spacer

AbstractAn unidentified monogenean diplozoid species was collected from the gills of moggel in the Vaal River and Vaal Dam, South Africa. Specimens were removed from gills of the hosts and observed using light and electron microscopy to compare these diplozoids with known species. The second internal transcribed spacer (ITS2) of the ribosomal gene was amplified, sequenced and compared to that of other diplozoid taxa. Morphological species delimitation was used to determine the identity of these diplozoids, but they did not match the description of any diplozoid taxa. This species is recognized by the specific size of the hooks, number of plicae in posterior and trapezoid anterior projection of the median sclerite connecting to the clamp jaws via a single sclerite, occasionally with two small additional sclerites. Genetic characteristics based on sequence data from the ITS2 region also distinguish this taxon from all other diplozoid taxa. This South African diplozoid grouped in the same clade as Paradiplozoon ichthyoxanthon Avenant-Oldewage, 2013. Data clearly indicate that diplozoids collected from moggel represent a new, distinct taxon of Paradiplozoon Akhmerov, 1974 and are described here as Paradiplozoon vaalense n. sp.

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