Climate and landscape drivers of tree decline in a Mediterranean ecoregion
Article first published online: 26 FEB 2013
© 2012 The Authors. Ecology and Evolution published by Blackwell Publishing Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Ecology and Evolution
Volume 3, Issue 1, pages 67–79, January 2013
How to Cite
Ecology and Evolution 2013; 3(1): 67–79
- Issue published online: 26 FEB 2013
- Article first published online: 26 FEB 2013
- Manuscript Accepted: 1 NOV 2012
- Manuscript Revised: 26 OCT 2012
- Manuscript Received: 8 OCT 2012
- Western Australia Centre of Excellence for Climate Change
- Woodland and Forest Health
- Climate change;
- Eucalyptus wandoo;
- forest canopy health;
- southwest Western Australia;
- tree crown health
Climate change and anthropogenic land use are increasingly affecting the resilience of natural ecosystems. In Mediterranean ecoregions, forests and woodlands have shown progressive declines in health. This study focuses on the decline of an endemic woodland tree species, Eucalyptus wandoo (wandoo), occurring in the biodiversity hotspot of southwest Western Australia. We determined the change in health of wandoo stands between 2002 and 2008 across its geographic and climatic range, and associated this change in health with non-biotic variables focusing on: (1) fragment metrics; (2) topography; (3) soil characteristics; and (4) climate. Only fragment metrics and climate variables were found to be significantly related to the observed change in health. Stands that were small with high perimeter/area ratios were found to be most sensitive to health declines. Recent increases in autumn temperatures and decreases in annual rainfall were negatively affecting health of wandoo most prominently in the low rainfall zone of its climatic range. Together, these results suggest the onset of range contraction for this ecologically important species, which is likely to be exacerbated by projected future changes in climate. Our results emphasize the importance of establishing monitoring programs to identify changes in health and decline trends early to inform management strategies, particularly in the sensitive Mediterranean ecoregions.