A plant ecological study of the Rietvlei Nature Reserve, Gauteng Province

Abstract

English: This study was undertaken with the objective to identify and quantify different homogeneous management units on the Rietvlei Nature Reserve to facilitate more effective management as far as grazing utilization, burning and monitoring are concerned. Vegetation units had to be identified and mapped. From the communities different management units could be identified. The study area of 3 870 hectares is a proclaimed nature reserve and is situated southeast of Pretoria in the Gauteng Province. A phytosociological study of the vegetation was done using the Braun-Blanquet method. A total of 184 plots were sampled and classified using the Braun-Blanquet method and TWINSPAN. This study revealed that the vegetation of the Rietvlei Nature Reserve could be divided into six main communities, each with a number of sub-communities and some with variants. The communities identified were: Andropogon schirensis – Aristida congesta Community, Gladiolus crassifolius – Brachiaria serrata Community, Eragrostis chloromelas - Setaria sphacelata var sphacelata Community, Eragrostis chloromelas - Cynodon dactylon Community, Setaria verticillata – Phragmites australis Community and Arundinella nepalensis – Eleocharis dregeana Community. The different communities described were used as a basis for the representation of a vegetation map of the reserve and the demarcation of management areas for the Rietvlei Nature Reserve.

Afrikaans: Die doel van die studie was om homogene bestuurseenhede vir die Rietvlei Natuurreservaat te identifiseer en te kwantifiseer vir meer effektiewe bestuur van weiding, brand en monitering. Die plantegroeieenhede moes geïdentifiseer en gekarteer word. Uit die gemeenskappe moes verskillende bestuurseenhede geïdentifiseer word. Die studiegebied van 3 870 hektaar is ‘n geproklameerde natuurreservaat en is geleë suidoos van Pretoria in die Gauteng Provinsie. ‘n Phytososiologiese studie van die plantegroei is gedoen deur gebruik te maak van die Braun-Blanquet metode. ‘n Totaal van 184 plotte is uitgeplaas en geklassifiseer deur gebruik te maak van die Braun-Blanquet metode en TWINSPAN. Die studie het aangetoon dat die plantegroei van Rietvlei Natuurreservaat in ses hoof gemeenskappe ingedeel kan word, elk met ‘n aantal sub-gemeenskappe en sommiges met variante. Die gemeenskappe is geidentifiseer as: Andropogon schirensis – Aristida congesta Gemeenskap, Gladiolus crassifolius – Brachiaria serrata Gemeenskap, Eragrostis chloromelas - Setaria sphacelata var sphacelata Gemeenskap, Eragrostis chloromelas - Cynodon dactylon Gemeenskap, Setaria verticillata – Phragmites australis Gemeenskap en Arundinella nepalensis – Eleocharis dregeana Gemeenskap. Die verskillende gemeenskappe wat beskryf is, is gebruik as ‘n basis vir die optrek van ‘n plantegroei gemeenskap kaart vir die reservaat en die aanteken van bestuursgebiede vir die Rietvlei Natuurreservaat.