Plant biodiversity in an extreme environment genetic studies of origins, diversity and evolution in the antarctic

• Main Authors: Skotnicki, M. L., Selkirk, P. M.
• Other Authors: Bergstrom, D. M., Convey, P., Huiskes, A. H. L.
• Format: Book Part
• Language: English
• Published: Springer, Springer Nature 2006
• Subjects: Antarc*; Antarctic; Antarctic Peninsula; Antarctica; Ross Island; Victoria Land
• Online Access: https://researchers.mq.edu.au/en/publications/e1ab5024-4577-4aac-b323-d7c78648e829; https://doi.org/10.1007/1-4020-5277-4_8; http://www.scopus.com/inward/record.url?scp=84889956202&partnerID=8YFLogxK

Plants in Antarctica survive in one of the harshest environments on Earth. Less than 2% of the 14 million km2 that make up continental Antarctica is free of permanent ice and snow and therefore available for colonisation by plants. Vegetation is sparse and low-growing, and is dominated by mosses and lichens. Two species of flowering plants occur on the Antarctic Peninsula (Edwards and Lewis Smith 1988, Lewis Smith 2003), but none in continental Antarctica. The flora of continental Antarctica comprises 15 species of mosses (Lewis Smith 1984), one species of liverwort (Bednarek-Ochyra et al. 2000) and at least 88 taxa of lichens (Øvstedal and Lewis Smith 2001). Eight species of moss have been recorded from southern Victoria Land and Ross Island (Seppelt and Green 1998). Continental Antarctic moss species usually grow as small colonies, but some coalesce to form turfs up to several square metres in extent and with up to 70% ground cover (Lewis Smith 2003, 2005). In a few locations, turfs can cover almost 100% of the ground over 25m2 or more. Clumps and turfs of moss are found in areas sheltered from the strong winds common in this region: in depressions and cracks in the ground surface, drainage lines and near rocks. Mosses only grow in niches where some moisture is available in summer, such as melt water from glaciers and persistent snow banks, and melting snow accumulated amongst rocks, cracks and depressions in the ground surface. These mosses are subjected to extremes of cold, drought, wind and light, with plants south of 67°S existing for weeks or months each year in a freeze-dried state in complete darkness. In the harsh continental Antarctic environment with its short summer growing period, mosses do not reproduce sexually. Of the moss species recorded from southern Victoria Land and Ross Island, only Hennediella heimii is known to produce sporophytes (Seppelt et al. 1992), although mature sporophytes and shedding spores have not been recorded. Colonies originate either from immigrant propagules from other ...