Despite their wide separation, the sub-Antarctic islands have vegetation that is broadly similar in appearance. Typically there is a coastal fringe of tall Tussock grass which is often frequented by birds and seals; on South Georgia these plants reach 2m in height. Wet marshes and bogs are dominated by short rushes, mosses and liverworts which have accumulated deposits of peat several meters in depth over the past 10,000 years. Drier, shallower soils are often covered by short grassland which, in the more exposed situations, has a high proportion of mosses and lichens.
Sheltered hillsides have swards of burnet, a woody shrub-like plant, whose ripe fruits are covered by barbed burrs which readily attach to clothing. Windswept ridges, plateaux and high altitude areas have sparse "fellfield" vegetation of mosses, lichens and scattered tufts of wind-dwarfed grasses and compact ground-hugging cushion-like plants. Ledges, crevices and wet rock support a variety of mosses, liverworts, lichens and occasional ferns. On the sub-Antarctic Indian Ocean islands the large-leafed Kerguelen cabbage (Pringlea antiscorbutica) grows amongst small plants on sheltered "herbfield" slopes, and other unusually large-leaved herbs, including the MacQuarie Island cabbage (Stilbocarpa polaris) occur in similar communities on MacQuarie Island.
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Farther south, in the maritime Antarctic region of the South Sandwich, South Orkney and South Shetland islands, and west coast of the Antarctic Peninsula to 68 degrees S, only two flowering plants occur in a few scattered localities, the Antarctic hair grass (Deschampsia antarctica) and Antarctic pearlwort (Colobanthus quitensis). They often grow together on moist sunny, sheltered slopes near the shore.
However, the predominant Antarctic vegetation consists of mosses and lichens. Wetter areas are dominated by shallow mats and carpets of moss, while well drained hillsides may have tall turf-forming mosses which accumulate banks of frozen peat up to 2m in depth. A few species of liverworts and toadstools also inhabit the wetter moss communities.
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Drier habitats have a discontinuous colorful mosaic of small cushion-like mosses and bushy and encrusting lichens, the latter predominating wherever exposure to wind is high.
In and near penguin rookeries where the ground is continually trampled, and concentrations of phosphate and nitrogenous matter reach high levels that little exists but a leafy green alga (Prasiola crispa) forming extensive sheets.
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Coastal rocks receiving constant deluges of sea spray or the excrement of cliff-breeding sea birds, are typically covered by expanses of vivid red, orange and yellow lichens which contrast with the drab colors of other species on rocks away from such enrichment.
Coastal areas of continental Antarctica are more sparsely vegetated due to the much drier atmosphere, infrequent availability of melt water or rain, and strong winds. However, wherever shelter is afforded, small aggregations of moss cushions and turfs or encrustations of lichen may be found. A few species are found several hundred kilometers inland, particularly near breeding colonies of Snow Petrels and Antarctic Petrels.
Websites
• Australian Antarctic Data Centre fact files
Introductory information about Antarctic and subantarctic animals, plants and features.
• Prehistory
More background information on the prehistory of Antarctica.
• Antarctic Adventure 1997
Information on the geography and climate of Antarctica.
