Included here are the volcanic islands of St Helena and Ascension situated in the South Atlantic.

St Helena Sea Cliff Formations

The cliffs on St Helena can be up to 500 m high, but most of them are composed of layers of eroding rock and loose volcanic ash. The dry western cliffs are virtually devoid of vegetation, but the wetter eastern and southern cliffs support a scattering of plants, including number of endemics that have become extinct in other parts of the island such as Pelargonium cotyledonis (Geraniaceae) and Plantago robusta (Plantaginaceae). Sea cliffs are therefore considered to be of great importance for conservation.

References

Ashmole, P. & Ashmole, M. 2000. St Helena and Ascension Islands: a natural history. Anthony Nelson.

Balgooy, Van. M. M. J. 1969. A study of the diversity of island floras. Blumea, 17: 139-178.

Cronk, Q. C. B. 1980. Extinction and survival in the endemic vascular flora of Ascension Island. Biological Conservation, 17: 207-219.

Cronk, Q. C. B. 2000. The endemic flora of St Helena. Anthony Nelson.

Duffey, E. 1964. The terrestrial ecology of Ascension Island. Journal of Applied Ecology, 1: 219-251.

Wilkinson, D. D. 2004. The parable of Green Mountain: Ascension Island, ecosystem construction and ecological fitting. Journal of Biogeography, 31: 1-4.