NEWS
We parameterised our fire spread models
with the record of weather conditions
(temperature, humidity, wind strength
and direction) experienced during observed
fires, topography (slope, aspect)
and an existing Fynbos “fuel model”
that describes the various parameters of
vegetation that determine flammability
and fire spread.
Running the models for many iterations
allowed us to generate a map of the
probability of fire occurrence (or burn
probability) for each scenario. Comparing
the two revealed the change in burn
probability due to human influence. Finally,
we used this map of the change
in burn probability to predict the observed
fire record and where forest has
expanded into fynbos. It worked!!!
depend on fire.
the old infloresm
from fire. Withcausing
a crash in
While our models weren’t perfect, and
could do with many refinements, that
we were able to predict the fire record
and change in forest extent with some
confidence shows that the ignition
catchment concept is a useful heuristic
for predicting human influence on fire
regimes past and future.
With improved models this approach
could be used to inform fire and vegetation
management in the face of the
many global drivers of change, from
direct human influence to invasive species
(changes on fuel properties) or
even climate change (e.g. changes in
fire weather).
have been Fynbos,
ignition catchf
fire-dependent
ndron) clinging on
fire spread models
and human-altered
should be able to
n fire regime with a
racy. This is exactly
the Cape Peninsula
shadows and the
the Cape Peninsula
ded the perfect loeas,
because there
d of fire activity and
ere’s also a record
sensitive forest into
os over the same
with a benchmark
ctions.
It is imperative that we improve our
understanding of how and where we
are altering fire regimes so that this insidious
threat to biodiversity can be assessed
and the potential impacts managed.
Ideally, the ignition catchment
framework would be used proactively,
informing spatial land use decisions a
priori to avert or minimise the impact
of human activities on fire regimes and
ecosystems.
Literature cited
Slingsby, Jasper A., Glenn R. Moncrieff,
Annabelle J. Rogers and Edmund C.
February. 2020. Altered Ignition Catchments
Threaten a Hyperdiverse Fire-
Dependent Ecosystem. Global Change
Biology 26 (2): 616–28. https://doi.
org/10.1111/gcb.14861. Request article
Wilgen, Brian W. van, Navashni Govender,
Izak P. J. Smit, and Sandra Mac-
Fadyen. 2014. The Ongoing Development
of a Pragmatic and Adaptive Fire
Management Policy in a Large African
Savanna Protected Area. Journal of Environmental
Management 132 (January):
358–68. https://doi.org/10.1016/j.
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