SOME PROPERTIES OF SUSPENDED SEDIMENT ADSORBED CATIONS IN TURBID FRESHWATERS OF SOUTH AFRICA

SUMMARY

Large quantities of suspended sediments are common in many of South Africa's fresh-waters. Temporal and spatial variations in tile amounts of cations adsorbed were recorded. The adsorption appears to be dependent on valency, because greater quantities of the higher valencies are adsorbed. Ca⁺⁺ dominated the adsorbed cations and Mg the dissolved fraction. Water originating from the Beaufort Series contained high sodium concentrations. Fe⁺⁺ dominated the adsorbed minor cations. Large quantities of sediments transported by rivers enter impoundments. The adsorbed ions transported in this way are influenced by the type of suspended sediment and form a significant part of the total input of ions.