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

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IV - BURNED LAND MAPPING, FIRE SEVERITY DETERMINATION, AND VEGETATION RECOVERY ASSESSMENT
Figure 3 - (a) RGB 8-3-2 ASTER combination; commission errors with (b) BAI, (c) NBR, (d)
MIRBI.
Optimizing this algorithm by a semi-empiric choice of threshold values
requires well-trained operators and the availability of data on ground
assessed fires, but significantly improves the quality of classification: the
above mentioned surfaces are mapped with greater accuracy and no relevant
errors are found; an example of this situation is shown in Figure 4.
Figure 4 - From left to right: old wildfire; multiple threshold; optimized algorithm.
The multi-temporal approach is certainly the most complex of all methods
we dealt with, because image pre-processing is needed: results are similar
to the ones obtainable by multiple thresholding, with few commission
errors probably due to changes in land cover such as water level fluctuations
in water bodies (Figure 5).