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The occurrence and conservation status of Ceratogyrus bechuanicus and C. brachycephalus in the Transvaal, South Africa.
J.I. De Wet,H.J. Schoonbee
Koedoe : African Protected Area Conservation and Science , 1991, DOI: 10.4102/koedoe.v34i2.423
Abstract: In South Africa, Ceratogyrus is presently protected by the Transvaal Provincial Nature Conservation Ordinance. Owing to the demand for these spiders as pets they are classified as Commercially Threatened in terms of the ILJCN system. It was found, however, that the two known species in the Transvaal are well represented in protected areas which include nature reserves and national parks. Ceratogyrus bechuanicus is well represented in the Kruger National Park, Messina, D'nyala and Atherstone provincial nature reserves, as well as in the Klaserie and Sabi Sand private nature reserves in the Transvaal. The only conservation area in which C. brachycephalus has been located is the Messina Provincial Nature Reserve. With its much smaller distribution, C. brachycephalus has a higher conservation priority than C. bechuanicus. Applied ecological work needs to be done so that comprehensive species conservation plans for both species can be compiled.
Bioaccumulation of copper in the tissues of Potamonautes warreni (Calman) (Crustacea, Decapoda, Branchiura), from industrial, mine and sewage-polluted freshwater ecosystems
V.E. Steenkamp,H.H du Preez,H.J. Schoonbee
African Zoology , 2012,
Abstract: ENGLISH ABSTRACT: The copper concentration detected in the water and sediments of the Natalspruit River, Bronkhorstspruit River and Nooitgedacht Dam exceeded certain stated limits for the protection of aquatic life. Despite considerable individual variation, the general ranking of copper concentrations in the various tissues was carapace < muscle < gonads < midgut gland < gills. Seasonal variation was detected in the bioaccumulation of copper in crabs sampled from the Natalspruit River. However, this phenomenon did not occur in crabs from the other two water bodies. A significant increase in copper concentrations was detected with a decrease insize, indicating that the size of the crabs is an important influencing factor in the bioaccumulation of copper. It was also found that more copper accumulated in the ovary than in the testis per unit weight. The bioaccumulation factors (BF) calculated for the different tissues with respect to the water were highest in the gills and midgut gland (785,00 - 1257,50 and 432,00 - 1340,00, respectively). The BF with respect to the copper concentration in the sediments was comparatively low for all the tissues (<0,1O- 2,74). lt appears that P.warreni is able to regulate the copper concentrations in its various tissues and is therefore not a suitable indicator of the presence of copper in the aquatic environment. ********* AFRIKAANSE OPSOMMING: Die koperkonsentrasies wat gevind is in die water en sedimente van die Natalspruitrivier, Bronkhorstspruitrivier en Nooitgedacht Dam het sekere neergelegde riglyne vir die beskerming van akwatiese lewe oorskry. Ten spyte van ho individuele variasies, was die algemene verhouding in die koperkonsentrasies tussen die verskillende weefsels, karapaks < spier < gonades < spysverteringsklier
The Cambridge Companion to Postmodern Theology
Prosman, H.J.
Ars Disputandi : the Online Journal for Philosophy of Religion , 2004,
Abstract:
Kingship in the early state
H.J. Claessen
Bijdragen tot de Taal-, Land- en Volkenkunde , 1986,
Abstract:
Geplande economie en economische prognose
H.J. Duller
Bijdragen tot de Taal-, Land- en Volkenkunde , 1971,
Abstract:
Kulturele differensiasie in die australiese onderwys
H.J. Steyn
Koers : Bulletin for Christian Scholarship , 1988, DOI: 10.4102/koers.v53i1.870
Abstract: Cultural differentiation could be implemented in the educational system in one of three models namely the model of segregation, the model of integration or the model of cultural pluralism. In this article the degree of success in implementing the model of integration and the model of cultural pluralism in the educational system of Australia is investigated. The main finding was that the model of cultural pluralism was preferred as instrument to implement cultural differentiation. The main problem is still how to incorporate different cultures in one curriculum in order to enable the teacher to teach cultural diversities to one class group.
Wiskunde en spel
H.J. Schutte
Koers : Bulletin for Christian Scholarship , 1963, DOI: 10.4102/koers.v31i2.1458
Abstract: Die Wiskunde het nog steeds in die hi rargie van die wetenskappe ’n besondere plek geliad. Hiertoe dra by sowel sy besondere studie-objekte as die metodes wat by sy bestudering aangewend word, en bowendien ook die motiewe wat by die wiskundige ’n rol speel in die beoefening van sy vak. Die drang na onbetwisbare kennis is ’n vername beweegrede vir ondersoekingswerk by alle wetenskaplikes, insluitendc die wiskundige. Met die opkoms van die tegniek het die strewe na mag in toenemende mate die grondmotief vir fundamentele ondersoek geword, en ook aan hierdie strewe doen die wiskundige mee, al kom dit meer indirek tot uiting in die uiteindelike toepassingsgebiede van die Wiskunde en is dit nie in die onmiddellike suiwer wiskundige bedrywigheid so duidelik merkbaar nie.
Opleiding in die nywerheid — ’n opvoedkundige taak?
H.J. Steyn
Koers : Bulletin for Christian Scholarship , 1983, DOI: 10.4102/koers.v48i4.995
Abstract: The author points out that low productivity is one of the causes of inflation in South Africa. He suggests that, apart from other factors, training is an important component in the. Achievement of improved productivity. Training in industry should therefore be seen as an important part of the whole system of non-formal education within the framework of education as such. He pleads for closer liaison between formal and non-formal education sectors. Training in industry in the non-formal sense should also be seen as part of the educative process, and be determined by a specific world view. He also looks at the personnel utilized in the training process, and he points out the various skills that the personnel should master for the most efficient attainment of the various objectives.
Ontwikkelingsekonomie — Bestek en metode vir die studie daarvan
H.J. Weber
Koers : Bulletin for Christian Scholarship , 1974, DOI: 10.4102/koers.v39i1.1259
Abstract: Kennis van die probleme van onderontwikkelde gebiede is baie oud. Sodra verskille in ontwikkeldheid, hetsy op militêre, ekonomiese of ander gebiede duidelik word, en as sodanig erken word, wys die probleme van die minderontwikkelde gebiede hulself uit. Die ekonomiese geskiedenis is vol sodanige erkende verskille o.a. Hellenistiese kultuursentra, Imperiale Rome, Byzantium en sy florerende stadstaat; Noord- en Wes- Europa na die ontdekking van die nuwe wêreld en die vasstelling van effektiewe marinekommunikasie tussen Wes- Europa, Amerika en Oos-Asi .
Moontlikhede vir onderwysvoorsiening aan minderheidsgroepe in Suid-Afrika
H.J. Steyn
Koers : Bulletin for Christian Scholarship , 1998, DOI: 10.4102/koers.v63i1&2.521
Abstract: Options for education provision to minority groups in South Africa This article focuses on the educational rights o f minority groups. International trends in terms of the rights of minority groups have been identified regarding the right of unique educational provision, educational control and own education institutions. From an international perspective it can be deduced that South African minority groups can demand, without being discriminatory, the provision of own education which is to the advantage of the particular minority group as well as to the community at large. Minority groups can also request substantial involvement in educational control, which implies a system of decentralized educational control. These groups can also insist on own education institutions. It is indicated that if minority groups are not provided with the above-mentioned rights they can rightfully complain of unfair discrimination.
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