A record, for posterity, of the floristic composition of strandveld at Kommetjie-Scarborough, Cape Peninsula, Western Cape, South Africa

@tonyrebelo @jeremygilmore @troos @botaneek @vynbos @daverichardson @yvettevanwijk1941 @cmerry @rion_c @dianastuder @sedgesrock @charles_stirton @kenneth_oberlander

I have before me an unpublished report, about 30 years old, written by D M Mann, then a student at the University of Cape Town (https://en.wikipedia.org/wiki/University_of_Cape_Town).

It is titled 'Dynamic dune communities: their structure and the threats that face them', and documents the flora of certain small, coastal remnants of indigenous vegetation on the outskirts of the metropolitan area of Cape Town (https://en.wikipedia.org/wiki/Cape_Town).

The following show the general scenery:
https://www.gettyimages.co.uk/detail/photo/long-beach-with-the-village-kommetjie-in-the-royalty-free-image/1033726788?adppopup=true
https://en.wikipedia.org/wiki/Scarborough,_Western_Cape#/media/File:Scarborough_Western_Cape_Coastline_and_City_View.jpg

At the time, these remnants were beset by several degrading influences, particularly

invasion by the Australian small trees, Acacia cyclops (https://www.inaturalist.org/taxa/75249-Acacia-cyclops) and Acacia saligna (https://www.inaturalist.org/taxa/75255-Acacia-saligna), and
recreational trampling by Homo sapiens, resulting in damage to plants by windblown sand.

However, the vegetation remained intact enough that D M Mann was able to find a total of 27 sample plots (each 5 m X 10 m), in which to record the composition of the undisturbed vegetation, naturally exempt from wildfire, called 'strandveld' (https://en.wikipedia.org/wiki/Cape_Flats_Dune_Strandveld#:~:text=Wolfgat%20Nature%20Reserve-,Flora,Olifantsbos%2C%20Macassar%20and%20Gordons%20Bay.).

My interest in what might otherwise be forgotten as merely a small, unpublished study is based on the following perspective.

Unlike fynbos (https://en.wikipedia.org/wiki/Fynbos), which is ecologically fragile, strandveld is arguably resilient from various forms of disturbance. Therefore, strandveld may have long-term prospects for conservation in suburban settings. Even the problem of usurpation by Australian acacias may, in time, tend to resolve itself as the introduced plants integrate into the flora and become increasingly subject to damage by invertebrates.

Therefore, it may prove valuable to have a permanent record of the original floristic composition.

The study area was the coastal strip between Kommetjie (https://en.wikipedia.org/wiki/Kommetjie) and Scarborough (https://en.wikipedia.org/wiki/Scarborough,_Western_Cape), including

The substrate in the sample-plots is sand, derived from the beach rather than sandstone. This sand is partly calcareous, containing calcitic grains derived from the fragmented shells of marine organisms. The pH varied from 8 (alkaline) to 7 (neutral, where organic matter has accumulated under large, clonal shrubs of Sideroxylon inerme).

The strandveld sampled ranged from stands of low shrubs, including littoral elements associated with the edge of the beach, to stands of S. inerme, in which there were few additional plant species other than the liane Cynanchum obtusifolium (https://www.inaturalist.org/observations/36974049) - which in the study area occurred exclusively on S. inerme.

D M Mann recorded the cover-abundance of each species in each of the sample plots, according to the percentage categories used in the Braun-Blanquet system (https://link.springer.com/article/10.1007/bf01866672). However, I will not attempt to report the data here, at that level of detail.

RESULTS

Taking all of the sample plots collectively, the indigenous flora was as follows.

AIZOACEAE
Carpobrotus edulis (https://www.inaturalist.org/taxa/49322-Carpobrotus-edulis)
Jordaaniella dubia (https://www.inaturalist.org/taxa/532788-Jordaaniella-dubia)
Ruschia macowanii (https://www.inaturalist.org/taxa/491674-Ruschia-macowanii)
Tetragonia fruticosa (https://www.inaturalist.org/taxa/528778-Tetragonia-fruticosa)

AMARYLLIDACEAE
Brunsvigia orientalis (https://www.inaturalist.org/taxa/132796-Brunsvigia-orientalis)

ANACARDIACEAE
Searsia glauca (https://www.inaturalist.org/taxa/564119-Searsia-glauca)
Searsia laevigata (https://www.inaturalist.org/taxa/493489-Searsia-laevigata)
Searsia lucida (https://www.inaturalist.org/taxa/593894-Searsia-lucida)

ASCLEPIADACEAE
Cynanchum africanum (https://www.inaturalist.org/taxa/119577-Cynanchum-africanum)
Cynanchum obtusifolium (https://www.inaturalist.org/taxa/583200-Cynanchum-obtusifolium)

ASPARAGACEAE
Asparagus aethiopicus (https://www.inaturalist.org/taxa/75603-Asparagus-aethiopicus)
Asparagus lignosus (https://www.inaturalist.org/taxa/505800-Asparagus-lignosus)