Navigating terminology: When is fire a tool for 'maintaining' vs 'restoring'

ecosystems?

Tein McDonaldTein McDonald & AssociatesWoodburn NSW 2472

Fire and Restoration Conference. NCC May 26-27 2015.

Fire can be considered part of an ecosystem whose species have evolved in its presence and now depend on it - so maintaining fire at the appropriate regimes will be essential to maintaining such ecosystems.

Fire can be applied for two purposes: 1. Maintenance – to trigger normal successional

processes (i.e. appropriate cyclic disturbances)

2. Restoration – to repair degradation (i.e. reinstate conditions to enable recovery to occur.)

The difference between restoration and maintenance is whether degradation has occurred

Degradation can be said to have occurred where native species and functions have been lost (or are in process of being lost) and are unlikely to return without assistance (i.e. some threshold of irreversibility has been passed)

Some species may seem absent - but it is important to distinguish:

1. Natural ‘senescence’(i.e. some species merely absent above ground)

2. A degraded state where seed and bud banks are depleted due to:• Long-term weed domination• Long term fire exclusion

Soil seed banks and bud banks are an adaptation to:

• presence of fire AND• the medium term absence of fire!

NB: Mesic weed invasion is no different, as far as ecosystems are concerneds, from rainforest (mesic) species colonisation.

Reversing mesic weed invasion is possibleWarraroon Reserve, Lane Cove, Sydney 1992-2008

Before and during, 1992

After - 2008

Lane Cove National Park – 18 post-fire community groups 2004, reversing mesic shift

Fiddens Warf Road group – long dominated by Privet and natives regenerated en masse after wildfire

Using fire in fire adapted communities can stimulate more species to germinate in higher quantities - and flush out weed - enabling more efficient treatment.

But weed control is additionally needed!!

• 4 Native species (22 individuals)• 7 Weed Species (8 individuals)

Fire for regeneration in forested wetland (previously cleared and dominated by pasture grasses)

Spring 2012

Winter 2012

Summer 2014

Results:- lower weed follow-up requirement - more native species per unit area. i.e. 21 Forbs, 7 sedges, 8 grasses, 2 shrubs and 11 tree species across the 0.5ha site)

Cowards WetlandGap Road, Woodburn.

Minyumai Indigenous Protected Area (IPA) 1. Burnt Sept 2014

2. Broad sprayed Nov 20143. Spot sprayed Feb-Apr 2015

Results at May 2015: - 22 native species (incl 3 tree species)- 8 weed species (mainly Setaria

SETARIA TRIALS IN GRAZED CLEARING

AIM = Forest Red Gum Swamp Sclerophyll Forest

Cultural Restoration combined with ecological restoration

Fire for conservation is a new cultural practice in mainstream Australia…. butit is continuing or restoring an old practice for Indigenous Australians

…But cultural restoration is not always ecological restoration

…And ecological restoration is not always able to be applied.

It is most powerful where cultural and ecological restoration can be combined.

e.g. What about sites where fire can no longer be applied? Should we allow a shift the site to an alternative, locally occurring, fire-sensitive ecosystem? Would that still be restoration?

Not really – but it might have to be accepted in some areas where there is no alternative solution.

It would be more compatible with natural area restoration principles if restricted to areas where:• The site is naturally ecotonal• Restoration of natural flux is truly not feasible• The original ecosystem is not rare or highly valued• The shift does not add further degradation pressure to

other nearby ecosystems

Summary

• Fire to maintain – i.e. to avoid excessive senescence of the fire-adapted reference ecosystem that might lead to damage• Fire to restore – i.e. to revive declining diversity, reduce

fire sensitive rainforest species and trigger recovery of fire-adapted species’ – or flush weed to make it more viable to treat. • Shift to fire sensitive vegetation is a last resort

Cultural layer• Cultural landscapes – restoring cultural landscapes • Restoring and transforming cultural practices