Soil Fertility After Fire and Clear-Cutting
.......
CO
.L::
CJ)
~
.....
a
a
u:
V> Q) .....
a
LL
60
50
40
30
20
10
60
50
40
30
20
10
60
50
40
30
20
10
0
Control
cr-O.. D.
Total
H -oF -0L
'V
?-rr i f '0---0
o--o~_O- 0--0- - - -0- ----0
'V
'V
'V 'V
'V
'V
'V
Clearcutting
Burned
Ie Ashbed I
_. __- -cla_- -o
- -e--'V
0 - - - 0 - - 0
'V 'V
'V 'V
'V
'V
0 » . 0 > ' 0 » . 0 > ' 0 » . 0 >.
~
0 ~ m ~ 0 ~ m ~ 0 ~ m
«ZLL~«ZLL~«ZLL~
1989
1990
1991
Clearcutting
+ Fire
319
Fig. 22.1. Variation in oven-dry weight of different horizons of the forest floor of studied plots
during 2.5 years of experiment. Mean and standard error
zation rates in this period of rains after the summer drought, as corroborated
by litter bags results (data not shown). The ashbed plus H layer lost about
50% of its weight after the heavy rains in autumn 1989, that is a mean weight
loss of 19.9 ± 6.3 (SE) Mg ha- 1 • The heavy rains redistributed the forest floor
material: in the first post-fire sampling, 80% of the sampling points showed