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

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IV - BURNED LAND MAPPING, FIRE SEVERITY DETERMINATION, AND VEGETATION RECOVERY ASSESSMENT
3 - Preliminary results
The time-series of EVI values for Guarda (2797 ha), Santarém (19466 ha)
and Faro (25471 ha) fires and respective control areas, are shown in Fig.1.
All the three fires occurred during the first two weeks of August 2003, as
revealed by the sharp drop in EVI values for the burned areas (fig. 2 - black
line). Prior to the fires, the EVI time series for fire and control areas are
very similar, especially for the Santarém and Guarda fires. At the Faro site,
pre-fire EVI values of the control area appear consistently lower and more
strongly seasonal than those within the fire perimeter. The fire induced EVI
decrease is larger at the Santarém and Faro fires than at Guarda fire. There
are also clear differences in post-fire EVI response dynamics. At Santarém,
EVI values at the burned area take over two years to reach values similar
to those of the control area, while at Faro the recovery is faster (about
16months). The post-fire vegetation response displays a distinct pattern of
the Guarda site. Recovery is very fast, such that five months after the fire,
EVI values are higher within the fire perimeter then in the unburned control
area. By October 2004, i.e., 14 months after the fire, the fire affected
area and control EVI time series converge to very similar values.
Fig. 2 – EVI time series between February 2000 and December 2008 for Guarda (a), Santarém
(b) and Faro (c) fires.