7th Workshop on Forest Fire Management - EARSeL, European ...

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I - PRE-FIRE PLANNING AND MANAGEMENT
According to the Pan-European Forest/Non-Forest Map 2000, only 10.7% of
the ignition points fall into the Forest category. It must be considered that
the Forest class excludes woodlands with trees smaller than 5 m height,
burnt areas, forest roads and forest nurseries and regeneration (with less
than 30% canopy closure).
Data limitations derived from the incorrect insertion of coordinates in the
original file and the posterior transformation of projection systems must be
taken into account. Nevertheless, these results provide an important
insight about the fire domain concerning ignitions; land covers such as
artificial surfaces that represent the urban/rural interface and the agricultural
areas, shouldn’t be excluded from the analysis, since fires often start
in these areas and propagate to wildlands. These findings are in accordance
with previous studies, which show that around 95% of forest fires in
Mediterranean Europe are human-caused (e.g., Ne’eman et al., 2004).
To confirm the influence of human variables in the occurrence of fires, an
additional preliminary analysis was carried out, based on the distribution
of ignition points in relation to the roads network. Data of Portuguese
roads were obtained from TeleAtlas (2006-2009 TeleAtlas) and analysed
according to the type of roads (national roads and local roads). Buffers of
50, 100, 200 and 500 meters were created around the roads and the total
number of ignition points falling into each buffer was calculated.
It was found that the density of ignition points (IP/km2 /10) increases in
the classes up to 100 m distance from the roads, being more evident in the
local roads dataset (Fig. 2).
Figure 2 - Density of ignition points according to distance from the roads.