Wynand Vlok's research while affiliated with University of Johannesburg and other places

Publications (4)

Article
This study investigates the trophic transfer of persistent organic pollutants (POPs: PCBs, PBDEs, OCPs and PFASs) in the subtropical aquatic ecosystem of the Olifants River Basin (South Africa) by means of trophic magnification factors (TMFs). Relative trophic levels were determined by stable isotope analysis. POP levels in surface water, sediment...
Book
Full-text available
The construction of the Pongolapoort Dam in the Phongolo River started in 1960 with the purpose to supply irrigation water for the proposed sugarcane and cotton plantations in the adjacent floodplain, the Makhathini flats. The floodplain of approximately 10 000 ha increases in size to 13 000 ha at full inundation. The floodplain extends to the conf...
Technical Report
Full-text available
In this study macroinvertebrates, fish, amphibians and birds were selected as focal groups to represent the biodiversity spectrum from invertebrates, lover chordates to higher chordates. The single most important aspect that was identified by each of the four taxonomic groups was the integrity of the Phongolo floodplain and the Ndumo Nature Reserve...

Citations

... The most of the contaminants analysis are based on an estuarine environment (Mzimela et al., 2003;Nel and Froneman, 2015;Olisah et al., 2019;Erasmus et al., 2020). Besides, studies are based on pollution discharge from freshwater environment (Wepener et al., 2001;Verhaert et al., 2017;Shamuyarira and Gumbo, 2018) and these water discharges are normally effected by agricultural, sewage discharge, industrial and urban activities (Songca et al., 2013). Nevertheless, the pollutants in these estuarine and freshwater environment eventually get washed off into the marine coastal areas. ...
... The NGR was established in 1924 to conserve hippopotami (Hippopotamus amphibius) as they were being overhunted (Calverley and Downs, 2014a;Smit et al., 2016;Acosta et al., 2020;Fig. 2) and was later declared a Wetland of International Importance and became a Ramsar Site under the Ramsar Convention of 1997 (Dube et al., 2017(Dube et al., , 2019. ...