Fjölrit RALA - 05.12.1999, Blaðsíða 39

Giuseppe Pulina etal.
37
For each municipality the following data were acquired:
• Fires: number of fires (NF) and extent of affected surfaces (pastures, wood-
land) for each year (source: Regional Forestry Administration).
• Livestock: sheep number (SN) and cattle number in 1980 and in 1990 (source:
Italian General Agricultural Censuses).
• Population: economically active population and unemployed population in
1980 and 1990 (source: Italian General Population Censuses).
The following data were calculated for each municipality:
• Number of fire outbreaks per km2 (NO); total bumed area (S); percentage of
bumed area in relation to the municipality area (% S).
• Change in the number of sheep (ASN); change in the number of sheep and
cattle (ALSU) expressed in Livestock Unit (LSU= 450 kg BW corresponding
to 1 cattle, 10 sheep); sheep stockingrate (SR).
• Unemployment rate (UR).
All municipalities were classified according to their tourist activity, ranging from
high to low and absent.
Statistical analyses concemed:
• Pearson correlation analvsis among the variables.
• Regression analysis between ASN and bumed areas (S).
• ANOVA, using the GLM procedure, to highlight the influence of tourist class
on the number of outbreaks per km'2 and burned surfaces as percentage of
total municipality area (%S).
RESULTS AND DISCUSSION
The correlation analysis (Table 1) showed a positive correlation (0.592) between
sheep number (SN) and total surface swept by fire (S). The same trend could be ob-
served when considering sheep number change (ASN) and surfaces affected by fire,
even though the correlation was lower (0.35). The number of fires (NF) was positively
correlated with sheep number (0.467) rather than with sheep number change (0.133).
Table 1. Correlation coefficients for the relationship between fire and other factors.
NF NO S SN ASN ALSU
NO 0.508
S 0.700 0.157
SN 0.467 -0.047 0.592
ASN 0.133 -0.080 0.350 0.787
ALSU 0.040 -0.014 0.290 0.556 : 0.852
SR -0.036 0.208 0.002 0.304 0.336 0.367
UR -0.015 0.223 -0.122 -0.147 -0.009 0.072
Legenda: NF = 1 Nuraber of fires. NO = Number of fires per km2.
S = ' Total bumed surface. SN = Sheep number.
ASN = : Sheep number change. ALSU= Livestock units change.
SR = : Sheep stocking rate. UR = Unemployment rate.
Correlation coefficients with P<0.05 are in italics.
SR
0.169