Abstract
Ph.D.
An investigation was made into the physical, chemical and biological
conditions of the Elsburgspruit to establish the extent and quality of
pollution over a period of two and a half years from January 1987 June
1989. The results obtained during the investigation can be summarised as
follows. Serious faecal pollution as reflected by faecal coliforms, faecal
streptococci and coliphage organisms occurs over a large stretch of the
river, posing a health risk to the people using the recreational area at'
Vosloosrust, downstream from the Elsburgspruit near Kathlehong. The
occurrence and large numbers of coliphage organisms occurring at certain
sampling localities suggest the possible presence of the pathogenic viruses
Salmonella, Pseudomonas and Candida.
Effluent and seepage waters from mining areas, discharged into the
Elsburgspruit were found to be low in pH and high in concentrations of
certain metals such as zinc, manganese and iron. Due to the large volume
of this particular effluent, the effects thereof on the water quality and
fauna of the streams are felt over a distance of more than seven
kilometres. As a result, the recovery of the stream from pollution is
severely retarded. A number of species of the numerically dominant aquatic
and semi-aquatic macrophytes which occurred within the flood-plain of the
Elsburgspruit, were found to be able to absorb and to accumulate
substantial concentrations of the various heavy metals, directly from the
water, or from adjacent moist soils. It was also found that the Spanish
reed, Arundo donax, which covers a large area of the wetland region of the
Elsburgspruit in its lower section, absorbed and accumulated substantial
quantities of the different heavy metals from the water of the stream. A
comparison was made of the extent to which metals are deposited into the
sediment under both acidic and alkaline conditions...