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through 2008. The area burnt varied widely from year to year but has gradually
diminished since the 1980s. The mean annual area burnt during this period was
1878 ha. The mean annual estimate of direct carbon emissions from forest
fires in
Japan was 15.8 Gg C year
−
1
and ranged between 2.7 and 60.4 Gg C year
−
1
. The
mean annual trace gas emissions were 49.4 Gg CO
2
year
−
1
, 3.4 Gg CO year
−
1
,
0.15 Gg CH
4
year
−
1
and 0.18 Gg NMHC year
−
1
. Although the carbon emissions
varied widely from year to year based on the area burnt, they decreased dramati-
cally from the 1980s onward. The interannual variations in trace gases parallel the
total carbon emissions. The direct emissions from forest
fires in Japan were sub-
stantially lower compared with the mean annual net primary production of Japanese
forests or the carbon release in other countries and regions. However, the average
annual carbon released per unit area burnt was comparable to that estimated in other
regions and rose gradually with the increasing age of plantations.
8.4.5 Wild
res and Biocomplexity
A wild
fire in an area of combustible vegetation. This phe-
nomenon is inseparably linked with biocomplexity of plant community. Wild
fire is an uncontrolled
re
changes a structure of plant community causing the disbalance of ecological pro-
cesses on burned area. One principal indicator of natural ecosystem is the level of
carbon exchange between its elements. Other ecological processes within the
ecosystem correlate with the carbon cycle. In other words, carbon cycle charac-
terizes a level of interactions between all living and plant organisms of ecosystem.
Wild
uxes a
ij
between ith and jth eco-
system elements are functions of time t, temperature T, soil moisture W, and solar
energy E. Approximate scheme of carbon
re impacts on the carbon cycle. Carbon
fl
fluxes in the forest ecosystem can be
presented by the chart of Fig.
8.16
. Certainly, parameter a
ij
can be evaluated by the
relation of C:N or by other alternative model. Somehow or other, biocomplexity
indicator is showing the forest
fl
fire consequences. Balance equations for the scheme
of Fig.
8.16
have the following form:
x
1
=
dt ¼ a
61
a
14
dx
2
=
dt ¼ a
62
a
24
dx
3
=
dt ¼ a
63
a
34
dx
4
=
dt ¼ a
14
þ
a
34
þ
a
24
a
45
a
47
dx
5
=
dt ¼ a
45
a
56
a
57
dx
6
=
dt ¼ a
56
þ
a
46
a
62
a
61
a
63
dx
7
=
dt ¼ a
47
þ
a
57
Fluxes a
6i
(i = 1, 2, 3) are parameterized by the photosynthesis equations taking
into account a transpiration. Velocities of the litter and soil organic matter
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