Abstract:
Prunus africana has been severely exploited for its valuable products rendering it unstable and at risk of
extinction. Studies were therefore carried out on its regeneration density and population structure across different human
disturbance gradients in South West Mau Forest (SWMF) Kenya. Four study sites with {undisturbed, low, moderate and high}
human disturbances were identified in SWMF. In each study site three line transects, 100 m apart and running up to 1 km
inside the forest were established. Four sample plots 20 m x 50 m were laid at 250 m intervals along each line transect then
divided further into 10 subplots each 10 m x 10 m and nested 5m x 5 m sub-subplots. At the centre of each sub-subplot, a 1 m
x 1 m quadrant was laid. In each sub plot Diameter at Breast Height (DBH) of all adult trees and poles were measured while
the number of saplings in each sub-subplot and seedlings in each quadrant were counted. Light screening efficiency was
evaluated in all study sites as an indicator of canopy openings. One way Analysis of Variance (ANOVA) was used to test for
significant differences of the studied variables, Tukey Post Hoc test was used in pairwise mean comparison and parametric
Pearson correlation analysis was used to test for relationship between variables. Bar graphs and line graphs were used to depict
trends in population structure and diameter-size distribution respectively. Animal trails, old charcoal production sites, tree
harvesting and debarking of P. africana were found as significant human forest disturbances (p < 0.05) that negatively
influenced its relative abundance (r = -0.077). Canopy openings as consequence of disturbance negatively influenced its
regeneration density (r = -0.089). The relatively undisturbed site of the forest had a stable population structure for P. africana
that followed reverse-J curve irrespective of the high debarking rate (90%) that decreased across the disturbance gradient.
These findings suggest a need for designing sustainable management strategies that will lead to rehabilitation, restoration and
monitoring of P. africana population dynamics in SWMF.
