Today, World Environment Day focuses on forests and the environmental services that they provide, such as clean air, water, timber and food.
Forests are the green lungs of the earth, they create and maintain soil fertility and they are home to more than half of the terrestrial species of animals, plants and insects.
Antarctica has its own ‘forests’ in the mosses, lichens and liverworts that cling to the ice-free areas of the continent. In fact Casey, in the Australian Antarctic Territory, has the most extensive and best developed plant communities in continental Antarctica. For this reason it is sometimes called the ‘Daintree’ of Antarctica. The largest plants are the mosses which, like miniature old growth forests, grow incredibly slowly. A single moss shoot may be over 100 years old. About 100 species of mosses and 30 species of liverworts have been identified in Antarctica.
Climate change has produced drying and warming in the east Antarctic region and the ozone hole has also elevated UVB radiation over the entire continent. Increased carbon dioxide, temperatures and UV could have a serious effect on plant life in the Antarctic, although research on moss has shown that some species may cope better than others.
One effect of climate change will be to increase the amount of available habitat for colonisation, especially in coastal areas and on the Antarctic Peninsula. As a result, possibly the biggest threat to plant ecosystems in Antarctica could be the natural or accidental (by humans) introduction of new plant species from elsewhere.
The Australian Antarctic program’s research on trends and sensitivity to change is looking at the impact of climate change on terrestrial, lake and marine ecosystems, including the moss beds at Casey. The book Trends in Antarctic Terrestrial and Limnetic Ecosystems, co-edited by Australian Antarctic Division terrestrial ecologist Dr Dana Bergstrom, also provides a synthesis of the likely effects of climate change on Antarctic terrestrial and freshwater ecosystems.