The effect of environmental change on vascular plant and cryptogam communities from the Falkland Islands and the Maritime Antarctic

Despite the strong difference in plant growth form dominance between the Falkland Islands and the Maritime Antarctic, communities across the gradient did not differ in total diversity and species number.During the summer months, the experimental temperature increase at 5 cm height in the vegetation was similar between the locations (0.7°C across the study). In general, the response to this experimental warming was low. Total lichen cover showed a non-significant decreasing trend at Signy Island (p < 0.06). In the grass community at the Falkland Islands total vegetation cover decreased more in the OTCs than in adjacent control plots, and two species disappeared within the OTCs after only two years. This was most likely a combined consequence of a previous dry summer and the increase in temperature caused by the OTCs.These results suggest that small temperature increases may rapidly lead to decreased soil moisture, resulting in more stressful conditions for plants. The more open plant communities (grass and lichen) appeared more negatively affected by such changes than dense communities (dwarf shrub and moss).Antarctica is the coldest, driest, windiest and highest continent on Earth. As a result, plant growth is largely limited to the coastal areas of the sub- and maritime-Antarctic regions. In these regions, there are small areas where vascular plants and cryptogams (mosses and lichens) can grow due to the summer melt of snow and ice. Due to the harsh climate, Antarctic vegetation mainly consists of cryptogams and there are only two vascular plant species (Deschampsia antarctica and Colobanthus quitensis). The extreme environmental conditions provide one of the main reasons why ecosystems in the Antarctic regions are relatively simple, have a poorly developed trophic structure and are species poor as compared to lower latitude ecosystems [1,2].Recent climate changes documented over the last 50 years along the Antarctic Peninsula have been far greater than seen at low