Richard Harper

Climate change adaptation for forestry: learning from recurrent

droughts

Alcoa Chair in Sustainable Water Management

Collaborators

John McGrath (CRC Future Farm Industries)

Keith Smettem (University of WA)

Don McGuire (ForestrySA)

Tom Baker (University of Melbourne)

Brad Evans (Murdoch University)

Overview…

Projections of climate change for southern Australia often describe a change in the water balance

Region has both had a general drying trend and recurrent droughts with severe effects; the forest industry has adapted

Are these droughts analogues of future climate change?

How did adaptation occur?

Are the institutional structures in place to allow future adaptation?

Australia’s forests and land use

(State of the Forests Report, 2008, p. 5)

Total forest area 149x106 ha

138x106 ha native Eucalyptus & Acacia forests

9x106 ha native Eucalyptus production forests

1x106 ha plantation Pinus

1x106 ha plantation Eucalyptus

Key component of carbon mitigation, expansion into new areas

CSIRO & BOM (2010)

The climate has been drying…

(Harper et al. 2009, Plant Soil 324: 199-207 )

With recurrent droughts…

(Photo: R.J. Harper)

(Photos: R.J. Harper)

(Photo: J.F. McGrath)

(Photo: J.F. McGrath)

Drought responses

Regional responses - not all trees die.

Differences with:

o Soils – soil water holding capacity

o Slope position

o Aspect

o Species

o Management as it affects leaf area (plantation density, fertilization etc)

Responses: Site selection

Better definition of climate and species matching

Better definition of sites to depths of several metres

Maximizing soil water storage; avoid “shallow” sites

(Harper et al. 2008, RIRDC Report 08/002 )

Exploring drought response: effects of species, planting density and slope position

How did responses occur?

Plantation research capability – State departments, CSIRO Forestry, industry, universities

Organizational expertise:

e.g. SA– species trials within same organization over 100 years

Memory of previous events and responses

Able to respond to changes and devise new systems

Does this adaptive capacity remain?

Conclude with some questions…

Are droughts an adequate analogue of future climate change?

Will current institutional arrangements allow future adaptation?

Is there adequate research infrastructure in place (species, silviculture) to demonstrate alternatives?

Will there be adequate expertise to respond to surprises?

Mountain pine beetle

(earthobservatory.nasa.gov/IOTD/view.php?id=36209)

Emissions: 50 Mt CO2/year over 37 Mha (Kurz et al. 2008)