| dc.description.abstract | Mt. Marsabit forest is located in Marsabit district, northern Kenya. It is the main water
catchment for the nearby Marsabit town and the immediate environs. It is also an
important refuge for several endemic, rare and threatened species. Plant species
diversity, community structure and impact of human activities were undertaken to
inform its conservation and sustainable utilization of the forest resources. Three
transects of 18 x 1.2, 12 x 1.2 and 5 x 1 km2with 400 x 400 m quadrats were laid
out at different parts of the forest. Randomly distributed 154 sample plots of 20 x 5 m
were used for the assessments. In each plot, all trees, shrubs, herbs, climbers and
lianas were identified and enumerated. The numbers of individuals of each tree and
shrub species were counted. The height and dbh (2::5 cm dbh) were measured to
determine community structure. The following values were calculated for each tree
and shrub species; relative density, relative frequency, relative dominance and
importance value index. Diversity was determined using Shannon-Wiener and
Simpson's diversity indices. Indicators of human activities in the forest and wildlife
disturbance were observed. A total 'of 70 species were sampled, of which, 52
species were trees and shrubs, .12 were herbs and 6 were climbers. Rinorea
convallaroides (8ak.f.}' Eyles ssp. marsabitensis Grey-Wilson (Violaceae), an
endemic and rare species, and Drypetes gerrardii (Hutch.) (Euphorbiaceae), were
the two most important species. Their dominance led to low species diversity in the
forest. Several species of ecological concern were also found. Diversity was 2.735
(Shannon-Wiener), 0.880 (Simpson's) and 0.296 (Evenness). The structure had five
strata corresponding to that of the Kenyan natural forest. There was variation among
and within transects and eight plant species associations were identified. These
were; Croton dichogamous community, Strychnos henningsiilTeclea simplicifolia
association, Orypetes gerrardii/Rinorea convallaroides association, Cassipourea
malosana community, Croton megalocarpus/Olea europaea association, Orypetes
gerrardii community, mixed forest species and secondary forest species community.
Profile diagrams were established for each association. There was strong evidence
of overgrazing, destruction by wild herbivores and human extractive activities. In
order to reduce further degradation of the forest, it is recommended that the forest
adjacent communities be made aware of the appropriate agroforestry technologies
and sustainable utilization of the forest. Creation of woodlots of indigenous species
from Mt. Marsabit forest should also be introduced. This will provide timber, fuel
wood, medicine and fodder to the people living around the forest. | en |
