3.1. Forest inventory
The pristine forest has a lower number of trees exceeding 6 cm diameter at 1.3m height (839 ± 154 ha) than the Eucalyptus plantation(983 ± 93 ha)
However, the Nyungwe forest has a much
higher total basal area of 62.7 ± 27.2m2 ha1 compared to the Eucalyptus
plantation (13.7 ± 2.2m2 ha1) because of the larger tree
diameters of PE species in the Nyungwe forest (Table 2).
In the Nyungwe forest, the dominant species was PE with the highest average
tree number (322 ± 38 ha1) and a basal area of 58.6 ± 2.9 m2
ha1. The number of CP and CG trees in Nyungwe was 278 ± 79
and 239 ± 96 ha1, respectively, with a basal area of only 2.2 ± 1.5
and 1.9 ± 1.1m2 ha1, respectively.
In the pristine forest, the number
of trees with a diameter at 1.3m height exceeding 30 cm accounted
for 27% of the total tree number.
In the Eucalyptus plantation, there
were no trees exceeding 30 cm at 1.3m height. The canopy was
more open in the Eucalyptus plantation than in the Nyungwe forest.
Canopy openness varied from 17.9% to 39.3% in Nyungwe forest and
from 38.9% to 53.1%in the Eucalyptus plantation.