Supervisory panel: Professor David Norton 1 , Professor Paula Jameson 2 , Dr. Timothy Curran 3 and Dr. Colin Meurk 4 1– School of Forestry, University of Canterbury 2 – School of Biological Science, University of Canterbury 3 – Department of Pest-management and Conservation, Lincoln University 4 – Landcare Research, Lincoln, New Zealand Ana M.C. Teixeira PhD Student School of Forestry University of Canterbury Post-fire vegetation resprouting on the Port Hills: implications for restoration
Transcript
Supervisory panel: Professor David Norton1, Professor Paula Jameson2, Dr. Timothy Curran3 and Dr. Colin Meurk4
1– School of Forestry, University of Canterbury
2 – School of Biological Science, University of Canterbury
3 – Department of Pest-management and Conservation, Lincoln University
4 – Landcare Research, Lincoln, New Zealand
Ana M.C. TeixeiraPhD Student
School of Forestry
University of Canterbury
Post-fire vegetation resprouting on the Port Hills:implications for restoration
Port Hills fire
Post-fire vegetation resprouting capability
Implications for restoration
Structure
Post-fire vegetation resprouting on the Port Hills :implications for restoration
Occurred between 13-16 February 2017, in Christchurch wildland-urban interface
One of the New Zealand’s most devastating wildfires of recent times
Two fires merged, the wind was strong, and the fire danger rate was very high -extreme
Destroyed 9 homes and damaged 5 others, and resulted in the evacuation of more than 1400 residents
Burned approximately 1500 ha
Port Hills fire
Satellite image of the area previous to the fire
Satellite image of the area after the fire
Approximately:
- 530 ha pine plantation
- 475 ha exotic shrubland dominated by Ulexeuropaeus and Cytisusscoparius
- 315 ha pastureland and open area
- 155 ha of native forest in different stages of regeneration
Port Hills fire
Post-fire resprouting capability
Considering that fire frequency and severity are likely to increase as
a consequence of climate change, understanding the post-fire
vegetation responses is of strategic importance for planning future
conservation and restoration actions.
While resprouting is well-documented in fire-prone biomes, information is scarce in non-fire prone ecosystems, such as New Zealand forests.
Which native species are able to survive by
resprouting?
Resprouts were counted and classified according to their position - basal
and epicormic.
Growth form, crown architecture and bark characteristics were used to
identify the species
Extra sampling was conducted in the plots` surrounding areas
Post-fire resprouting capability
Woody vegetation was sampled in ten 10x10m plots
Assessments made 5 months and 10 months after the fire
Included all woody plants with more than 5 cm diameter
Any sign of resprouting was checked and recorded
Plots location
Note: Resprouting proportion was dependent on the species for the species highlighted with * (χ = 196.2; d.f. = 9; p<0.001)
The majority of the native species were not capable of resprouting
Consequence of their evolution in an environment with a naturally low fire frequency
Lack fire adaptation
Even lacking fire adaptation, some of native species were capable of resprouting
Resprouting is a common response to many types of disturbance, including wind, herbivory, hurricanes, and floods
Resprout ability was probably shaped by other evolutionary forces rather than fire
Will provide these species with a competitive advantage in the post-fire recovery
Non - resprouters Resprouters
Native species - resprouting capability
Exotic woody species that benefit from fire events are common and widespread on the Port Hills landscape (eg. Ulex eropaeus and Cystusscoparius)
These species are fire adapted and capable of recruiting seedlings with great efficiency
In this competitive environment, the native species’ resprouting ability will be a key feature
Resprouting confers advantages in the recovery process, as resprouts often grow faster then seedlings
Native species - resprouting capability
Non - resproutersResprouters
Will persist after fire
Recover more efficiently
From a conservation and restoration point of view, resprouters will generally demand less active management to re-establish
The recovery will rely on dispersed seeds from neighbour populations (metapopulation dynamics)
If this dispersion is not efficient and there is great competition pressure, the recovery will probably be very slow
More likely to require active management to re-establish
Native species - resprouting capability
The incorporation of the resprouting trait in restoration plans can be relevant, especially in areas susceptible to fire events
Urban restoration context: urban-wildland interfaces are usually susceptible to fire, because fire risk increases through accidental ignition sources such as mower, blade strikes, recreational fires and fireworks, escaped rubbish burns or electrical infrastructure faults as well as through intentional arson
By planting higher proportions of resprouters, it is possible to engineer more fire resilient restoration plantings
