Establishing vegetation on Kimberlite mine tailings: 2. Field trials

Abstract

A series of field experiments were carried out on kimberlite mine tailings located at Cullinan in the Transvaal. The most successful species in pure sward were Chloris gay ana, Cynodon aethopicus, Eragrostis curvula, E. tef, Pennisetum purpureum, Melilotus alba and Medicago sativa. Growth of grasses in the absence of substantial applications of fertilizer N and P was negligible. Additions of sewage sludge considerably improved initial performances, but supplementary N and P was necessary to maintain satisfactory growth. Despite conditions of severe moisture stress, a good cover was produced by a mixed sward with C. gayana, E. curvula, M. alba and M. sativa being the dominant species. Sewage sludge in combination with fertilizer N and P resulted in excellent growth of C. gayana, E. tef and C. aethopicus on a steep slope (± 35°). However, in the absence of sewage sludge, growth was limited mainly to the vegetatively propagated C. aethopicus.

Uittreksel

‘n Reeks veldproewe is op Kimberlite gewaste grond te Cullinan, Transvaal uitgevoer. Daarvan is die mees geslaagde spesies in suiwer gemeenskappe Chloris gayana, Cynodon aethopicus, Eragrostis curvula, E. tef, Pennisetum purpureum, Melilotus alba en Medicago sativa. In die afwesigheid van kunsmis N en P was plantegroei nietig. Byvoegsel van riools‐lyk het aanvanklike vertoning aansienlik verbeter, maar aanvullende N en P was noodsaaklik om bevredigende groei te behou. Ten sptye van strawwe nattigheidstoestande is ‘n dekking opgelewer in ‘n gemengde gemeenskap waarin C. gayana, E. curvula, M. alba en M. sativa die oorheersende spesies was. Rioolslyk tesame met kunsmis N en P het C. gayana, E. tef en C. aethopicus op steil hellings (± 35°) uitstekend laat groei. In die afwesigheid van rioolslyk is groeie bepaal tot C. aethopicus, wat vegetatief voorgeplant is.

Notes

Based on an MSc. thesis submitted to the Departments of Pasture and Soil Science, University of Natal.