An approach to quantify the resilience of forest species

1. JoseV Moris, GiorgioVacchiano, Davide Ascoli, Renzo Motta
University ofTurin (ITALY)
Email: joseantonio.vazquezmoris@unito.it
Website: sites.google.com/site/josevmoris/
Perth III: Mountains of Our Future Earth
4-8 October 2015
AN APPROACH TO QUANTIFY THE RESILIENCE
OF FOREST SPECIES
AN EXAMPLE IN ALPINE LARCH (Larix decidua) FORESTS

2. The ability to stay in the same state
despite
disturbances
environmental changes
internal fluctuations
Resilience

3. Resilience of what?
larch forests

4. Resilience to what?
environmental gradients
land use changes
vegetation dynamics

5. ecological systems tend to be found
closed to attractors
they are more likely to stay within more
resilient states
the relationship between state variables
and drives are different depending on
the state
Assumptions

6. state variable
frequency

8. Variable Unit
State
Larix %
Topography
Elevation m
Slope °
Aspect Categorical
Forest structure
Canopy cover %
Basal area m
2
/ha
Land use
Pasture Categorical
Grazing %
Climate
Annual precipitation mm
Mean annual temperature °C
Mean temperature July °C
Mean temperature January °C
Gams index °
Icc
State variable and potential drivers

9. Frequency
distributions
ecological systems tend to be
found closed to attractors
multimodality of the state
variable
Source: Hirota et al. 2011
Science

13. Logistic
regressions
they are more likely to stay
within more resilient states
probability of finding specific
states
Source: Ratajckaz &
Nippert 2012 Science

16. Potential
analyses
Source: Scheffer et al.
2012 PNAS
the relationships between state
variables and drives vary
multiplicity in the relationships
state variable-drivers

17. R package “earlywarnings”  Dakos et al. 2012 PLOS ONE

20. frequency
distributions
logistic
regressions
potential
analyses
they
complement
each other
they share a
probabilistic
feature
better to use a
combination of
methods

21. Thank you for your attention