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

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I - PRE-FIRE PLANNING AND MANAGEMENT
Raster layer 1
Raster layer 2
Pixel containing the value 2236634
Where 2 = geoclimate unit (central alpine)
2 = deep montane (900 – 1100 m)
3 = crown closure (moderate)
6 = vegetation type (gras)
211= fire ID
Pixel containing the value 2711634
Where 2 = slope (20 - 30 °)
7 = aspect (west)
1 = deciduous (10%)
1 = coniferous (10%)
634 = fire ID
These two obtained raster layers were then used to highlight patterns of
similar forest and topographic parameters within the fire buffer. To do so,
raster values and their frequencies had to be exported into a database system
where the single parameters could be accessed via SQL language. With
SQL querries it was possible to identify parameters which occurred more
often than others.
One problem arise in this scenario; in very heterogeneous topographic landscapes
the size of a buffer directly influences the amount of pixels and
hence the variance of the value in that buffer. So in very big buffer which
exist when localisation was only very roughly possible information get lost
due to no possible identification of trends. To solve that problem classes of
buffer size were build and individually analyzed. It showed out that with
smaller buffer (< 300m) trends were becoming more visible and for further
analysis only buffers till 300 meter were considered.
Diagram 1 - Vegetation
composition in burned
areas.