Flora Biodiversity Assessment in Bonga, Boginda and Mankira Forest

The forests are also in the process of degradation due to a number of other factors such as
coffee growing in the forest, livestock rearing, and harvesting of fuelwood and
construction material. During clearing of the forest floor for coffee plantation everything
is cleared or slashed down. Hence seedlings and sometimes saplings of important tree
species are cleared together. In order to allow sun light some canopy trees are also cut
down. Livestock are seen in almost all forest areas and unless they are controlled they can
affect plant growth through trampling, browsing, breaking young saplings and trees.
Although it is difficult to substantiate the cause of death of trees in this study, insect and
pests introduced via animal and human may attack and affect the vitality of the forest.
Any scar created on a tree as result of animal or human contact may cause disease later
on it could kill the tree. In this study the number of stumps and dead trees were estimated
and the following results are obtained: dead trees per hectare are 292 in Bonga, 433 in
Boginda, and 359 in Mankira. The stumps were counted inorder to evaluate level of
exploitation and the results are 189 for Bonga, 27 for Boginda and 82 for Mankira. As the
figure shows Bonga forest is more affected by logging than the rest of the forests.
Because of absence of scientific management such as silvicultural practices, all forests of
the country, as well as those in the study area, are mostly affected by thick climbers that
are silviculturally and economically undesirable species. As a result of this phenomena
economically and silviculturally important tree species are crooked, bend and fluted.
Regeneration status too might be influenced negatively. Trees that are dead are rotting in
the forest. This might help in nutrient cycle but they might also harbor disease. Absence
of management plan also leads to over exploitation where annual cut exceeds mean
annual increment.
In conclusion existing threat to the forests is associated with anthropogenic activities.
Schmitt C. B. 2006, referring Gil et al., 2004 has emphasized how important Ethiopian
forests are in terms of gene pool and number of endemic species. However, the author
witnessed that human induced pressure threatened the existing forests of Kaffa zone. The
forests are in fragile and fragmented state. This great biodiversity coupled with the
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