Agriculture Reference
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Table 4.1 Percentage of the total number of fires and area burned in different parts of the Mediterranean Basin,
including the Iberian Peninsula (Portugal in the west; Valencia in the east; and Catalonia in the northeast), Greece
(Mount Parnitha National Park, Athens) and southwest Turkey (Dat ¸ a-Marmaris)
Only fires greater than 1 ha are included. Percentages are based on wildlands in the area of interest. In bold face are
the fire size classes that account for most ( > 50%) fires and area burned (elaborated from data provided by local forest
administrations in Portugal, Valencia and Catalonia, from M. Arianoutsou for Mt Parnitha, and ¸ . Tavsanoglu for
Dat ¸ a-Marmaris).
Portugal a
Valencia
Catalonia
Mt. Parnitha Datc¸ a-Marmaris
Fire size classes (ha) # fires Area # fires Area # fires Area # fires Area # fires
Area
10 0 -10 1
25.4
1.6
68
2.5
80.6
4.4
52.2
1.4
57.2
0.8
10 1 -10 2
57.7
15.8
22
8
14.6
7.4
26.1
7.0
28.9
4.6
10 2 -10 3
15.2
36.2
8.2
25.6
3.9
19.5
17.4
41.2
10.6
17
10 3 -10 4
1.6
31.5
1.7
41.34 0.78
38.8
4.3
50.3
2.8
38.5
10 4 -10 5
0.06
14.9
0.12
22.37 0.12
29.9
0.6
39.1
Period
1990-2005
1968-2007
1987-2002
1959-1996
1968-2008
Study area (ha)
5 310 900
1 209 264
1 956 791
26 000
138 000
a Small fires in Portugal are underestimated (compared with the other areas) because for some years
the data include only fires larger than 15 ha (1992), 50 ha (1993) and 10 ha (2005).
lightning was a more important fire ignition source. Most current fires are due to
anthropogenic ignition, either by negligence or intentionally. Human- and
lightning-ignited fires tend to have different geographical distributions; the former
are more concentrated in coastal areas, while the latter occur in inland areas at
higher elevation (Va´ zquez & Moreno 1998 ), a feature shared with other MTC
regions.
Most fires, including those from lightning, are concentrated in summer
when fuels are driest, although fires caused by pasture burning (typically
< 5% of the fires, Moreno et al. 1998 ) are distributed throughout the year.
The interannual variability in area burned is correlated with summer rainfall
in several different ways (Pausas 2004 ). During wet summers the area burned
is lower than in dry summers, undoubtedly due to higher fuel moisture.
Summer rainfall is also positively correlated with area burned for a time lag
of 2 yrs, suggesting that high rainfall may increase fuel loads that burn the
subsequent 2 yrs.
Due to the fragmented landscapes in the Mediterranean Basin, fires are rela-
tively small ( Table 4.1 ). Large and intense fires occur only in summer, and they
leave relatively few unburned patches. The few fires that occur in other seasons of
the year are less severe and leave abundant unburned patches (Pausas et al. 2003 ).
Fires are especially intense in forest plantations, particularly in areas that combine
summer drought with high rainfall during the rest of the year. As with most fire-
prone landscapes, the distribution of the number of fires vs. the burned area is
very skewed, with most of the burning being accounted for by a few very large fires
( Table 4.1 ).
 
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