1Present address: Environmental Protection and Change, Australian Antarctic Division, Department of Environment and Heritage, 203 Channel Highway Kingston, Tas. 7050, Australia.
Climate change manipulations show Antarctic flora is more strongly affected by elevated nutrients than water
Article first published online: 17 JUL 2006
Global Change Biology
Volume 12, Issue 9, pages 1800–1812, September 2006
How to Cite
WASLEY, J., ROBINSON, S. A., LOVELOCK, C. E. and POPP, M. (2006), Climate change manipulations show Antarctic flora is more strongly affected by elevated nutrients than water. Global Change Biology, 12: 1800–1812. doi: 10.1111/j.1365-2486.2006.01209.x
- Issue published online: 17 JUL 2006
- Article first published online: 17 JUL 2006
- Received 25 August 2005; revised version received 22 February 2006; accepted 21 March 2006
- chlorophyll fluorescence;
- community ecology;
- stable isotopes;
Climate change is expected to affect the high latitudes first and most severely, rendering Antarctica one of the most significant baseline environments for the study of global climate change. The indirect effects of climate warming, including changes to the availability of key environmental resources, such as water and nutrients, are likely to have a greater impact upon continental Antarctic terrestrial ecosystems than the effects of fluctuations in temperature alone. To investigate the likely impacts of a wetter climate on Antarctic terrestrial communities a multiseason, manipulative field experiment was conducted in the floristically important Windmill Islands region of East Antarctica. Four cryptogamic communities (pure bryophyte, moribund bryophyte, crustose and fructicose lichen-dominated) received increased water and/or nutrient additions over two consecutive summer seasons. The increased water approximated an 18% increase in snow melt days (0.2°C increase in temperature), while the nutrient addition of 3.5 g N m−2 yr−1 was within the range of soil N in the vicinity. A range of physiological and biochemical measurements were conducted in order to quantify the community response. While an overall increase in productivity in response to water and nutrient additions was observed, productivity appeared to respond more strongly to nutrient additions than to water additions. Pure bryophyte communities, and lichen communities dominated by the genus Usnea, showed stronger positive responses to nutrient additions, identifying some communities that may be better able to adapt and prosper under the ameliorating conditions associated with a warmer, wetter future climate. Under such a climate, productivity is overall likely to increase but some cryptogamic communities are likely to thrive more than others. Regeneration of moribund bryophytes appears likely only if a future moisture regime creates consistently moist conditions.