The physical environment and major plant communities of the Tankwa- Karoo National Park
Abstract
tic sediments of the Permian Ecca Group, with flat dolerite sills and dykes, underlie eight distinct plant communities. The plant communities can be divided into large open plains dominated by Galenia africana and Tripteris sp. in the erosion rills, Malephora luteola and Augea capensis common in the low lying areas and Zygophyllum microcarpum, Brownanthus ciliatus and Galenia crystallina common on the more shaly concave plains and low shale hills. Slightly elevated rocky areas are dominated by Ruschia cf. robusta, Ruschia spinosa communities, while crusts of stemless mesembs such as Rhinephyllum macra denium, Hereroa fimbriata and Cheiridopsis acuminata are found on the desert paved areas. Annual Asteraceae covers all the denuded and sparsely vegetated areas after good winter rains while annual mesembs colonise on the more sodic sites. A total of 259 plant species were collected sporadically over a period of eight years, this includes 65 succulents and seven species endemic to the Tanqua Karoo and immediate adjacent area of the Roggeveld Mountain Range and Sutherland. Four Tanqua Karoo endemic species were found in the park.

