The National Arboretum Canberra has two forests dedicated to research conducted with the Australian National University.
This collaborative research project focuses on the effects of climate variability, climate change and water use in two different types of eucalypt trees. The two species, Corymbia maculata (spotted gum) and Eucalyptus tricarpa (red ironbark), were specifically chosen due to their ability to cope with low rainfall and drought in different ways; spotted gum is a drought ‘avoider’ and uses an extensive root system to maintain its water intake, whereas red ironbark is a drought ‘tolerator’ and alters its metabolism to stop growing during drought.
The trees were planted in blocks of single species, arranged to allow three watering treatments and replication. This enables researchers to measure the effects of different watering regimes on the growth and survival of the trees, and consequently estimate the effects on many other eucalypt species. The blocks are large enough to allow them to be split to examine other important environmental effects such as competition.
Research investigators: Cris Brack (Chief investigator), Fenner School, Australian National University (ANU)
Michael Roderick, Tim Brown and Justin Borovitz, RSB, Australian National University
Albert van Dijk, Fenner School, Australian National University
Purpose of project
- Determine how these two different types of eucalypts respond to climate change with a drier climate and longer droughts, as projected to occur in many parts of Australia.
- Compare the growth and yield of two eucalypt species to various watering regimes.
- Determine the below ground moisture and temperature environments under the different forests and watering regimes, and how eucalypts respond to moisture stress (tree physiology)
- Allow the modelling of the response of eucalypts to varying climate scenarios, including more extreme rainfall patterns.
- Technical advances in the development and use of variable scale sensor arrays in the field.
- Improve the parameterisation of native tree growth and yield models.
- Examine how much carbon eucalypt forests sequester from the atmosphere.
- Explore whether the survival of eucalypts can be enhanced in a more variable climate (genetics).
Methods
- Randomised block design with: two eucalypt species of different physiological approaches to water stress; three watering treatments; replication.
- Manipulation of irrigation to the trees, to simulate drought in forests 98, 99 and 101 for a long-term, detailed study on the adaptability, genetics, physiology and ecology of the Eucalyptus genus
- Establishment of sensor network including:
- Two below ground sensors (moisture and temperature)
- Two above ground sensors (temperature, PAR)
- Two dendrometer sensors per treatment/species block.
- Use of giga-pixel, multi-focus time lapse camera capture.