Trees dominate many of the earth’s ecosystems and understanding how genetic variation within tree species affects dependent communities and ecosystem processes is a major frontier in ecology and forest management. Over two decades of research has established the highly diverse nature of the Eucalyptus globulus gene pool and significant genetic control of phenotypic variation in virtually all traits examined. The species exhibits genetic variation in susceptibility to disease, associated insect communities and marsupial browers, which in specific cases has been shown to be correlated with genetic variation in morphological or phytochemical traits. The variation in foliar chemistry in particular is highly heritable and genomic regions which affect key defensive chemicals have been identified. We are now using this well-studied eucalypt system to examine how the effects of genetic variation in a foundation tree species extend beyond the individual and population to impact dependent biodiversity and even ecosystem processes. We used a common garden field trial to show that genetic variation between geographical races of E. globulus not only acts to drive divergence in foliar and bark communities of the tree itself, but also affects associated detritivore communities, rates of wood/litter decay and soil nutrient availability. Such extended consequences of tree traits demonstrate the importance of considering tree genetic diversity in understanding and managing forest biodiversity and the services these forests provide.
2008 Old Forests New Management Conference, Hobart, Australia 17-21 February 2008
Proceedings of the 2008 Old Forests New Management Conference / pp.68