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

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IV - BURNED LAND MAPPING, FIRE SEVERITY DETERMINATION, AND VEGETATION RECOVERY ASSESSMENT
system of fire statistics. However, only a few examples of burning efficiency
(BE) quantification can be found in the literature. Most regional to global
emission estimates assume an average BE, either (i) for each major vegetation
or fuel type, or (ii) over the entire burned area, considering in both
cases all vegetation as completely burnt, which can lead to uncertainties
ranging from 23% to 46%. A different approach consists of estimating the
degree of biomass consumption in terms of burn severity (BS). Therefore,
this paper reports on work done to extend and improve the method, and to
test and apply it in a new region. The first goal was to test the simulation
model proposed by De Santis et al. (2009) to estimate BS in a new environment
and at a different scale, in this case two very large forest fires in
California. The second aim was to apply the BS estimated from satellite
imagery, in an attempt to adjust the BE values found in the literature.
2 - Materials and methods
Figure 1 - Methodological workflow followed in this study.
The study area corresponds to two very large forest fires (summer 2008)
located in the Big Sur region (Monterey, California, USA): the Indians Fire
(31,590 ha) and the Basin Complex Fire (65,942 ha). The study was comprised
of two consecutive phases (figure 1). First, BS was estimated using
a post-fire Landsat TM ortho-image and the inversion of the simulation
model proposed by De Santis et al. (2009). This approach was validated
using field data (40 plots), in terms of GeoCBI (De Santis and Chuvieco,
2009). In the second phase, the resulting BS map was used to scale liter-