The surprising diversity of the Klein Karoo
We recently visited the Klein Karoo. I had never realized this area is quite a bit different from the Great Karoo. Hereby, a short introduction into this captivating area. Most info comes from the very handy book, Plants of the Klein Karoo (Vlok & Schutte-Vlok, 2010)
With almost plant 3,200 species, a fascinating geology, and 19 different major habitat types the Klein Karoo is "the most complex and species rich arid area of the world". More than 400 plant species are endemic to the Klein Karoo. The area measures approximately 23,500 km2, most of which is situated in South Africa's Western Cape province, and a small area spilling into the Eastern Cape province. The area is shaped largely like an extended valley, with parallel-running mountain chains enclosing the Klein Karoo both from the north and south. These mountains are key drivers of the area's diversity.
Other factors that determine the habitat types include:
- Local geology (loamy soils in lowlands, sandy soils on the mountains)
- Annual rainfall (ranging from 1000 mm in the mountains to 200 mm in the lowlands)
- Temperature regimes
- Fire regimes
Vegetation types include subtropical thicket, succulent karoo, transitional shrublands and fynbos.
The lowlands and semi-desert are generally hot and dry, whereas the mountains provide cooler and wetter weather. At the same time, these same mountains provide water to the lowlands area.
Strategies employed by some fynbos plants to avoid seeds being eaten by rodents before fire comes:
Ant involvement -> burial underground and keeping seeds inside the flowerheads for many years.
Vitally important: tiny plants on the soil surface of the lowland areas. Form a 'living crust' and associate with lichens, mosses, fungi and bacteria, helping to prevent erosion and improving the infiltration of nutrients and water. Repeated trampling by certain heavy hoofed animals, especially ostriches, destroy this layer.
Back to overview