Original Research
A phytosociology survey and vegetation description of inselbergs in the uKhahlamba-Drakensberg Park World Heritage Site, South Africa
Submitted: 15 April 2014 | Published: 16 April 2015
About the author(s)
Robert F. Brand, Applied Behavioural Ecology & Ecosystem Research Unit, University of South Africa, South AfricaNacelle Collins, Free State Department of Economic Development, Tourism and Environmental Affairs, Free State, South Africa
P. Johann du Preez, Department of Plant Sciences, University of the Free State, South Africa
Abstract
No previous scientific surveys have been conducted on inselbergs in the Drakensberg. The aim of this study was to collect specimens, identify, describe and name the vegetation clusters and assess biogeographical connections with other Afromontane regions. A total of 103 relevés where sampled from six inselbergs. The plant sampling was carried out according to the Braun-Blanquet method with the plant and environmental data entered in TURBOVEG and exported as a Cornell Condensed format file (CC!) into Juice. Classification was completed using TWINSPAN (Two-way Indicator Species Analysis) (modified), resulting in 4 major communities, 11 communities, 13 sub-communities and 18 variants. Ordination (indirect) was carried out using CANOCO (version 4.5) to investigate the relationship between species. The four major communities identified are Rhodohypoxis rubella (wetland grass and forblands), Scirpus ficinioides – Crassula peploides (sheet rock grass and forblands), Pentaschistis exserta (high-altitude alpine grassland), previously undescribed, and Merxmuellera drakensbergensis – Helichrysum trilineatum (high-altitude alpine fynbos grassland), described in other vegetation and floristic studies. Four habitats were identified, namely wetlands, sheet rock shallow soil, highaltitude alpine grassland and deep soil high-altitude fynbos grasslands. Substrate and moisture availability appeared to be the defining micro-climatic conditions determining the different vegetation clusters whilst altitude is the overriding environmental factor influencing all vegetation.
Conservation implications: Rising temperatures as a result of carbon dioxide increase is predicted to drastically decrease the number of endemic and near-endemic montane species, whilst altering the composition of vegetation units which comprise the alpine vegetation.
Keywords
Metrics
Total abstract views: 4808Total article views: 11024
Crossref Citations
1. Dominant species of mid-elevation grasslands of the uKhahlamba-Drakensberg Park are predicted to be largely immune to climate change
Debbie Jewitt, Craig D. Morris, Tim G. O’Connor, Michelle J. Tedder
Journal of Mountain Science vol: 20 issue: 9 first page: 2468 year: 2023
doi: 10.1007/s11629-023-7928-6