TITLE:
Population Structure and Regeneration Status of Trichilia dregeana Sond. in Heavily and Less Disturbed Areas of Kalinzu Forest Reserve, South Western Uganda
AUTHORS:
Adalbert Aine-Omucunguzi, Dominic Byarugaba, Grace K. Rugunda
KEYWORDS:
Trichilia dregeana, Kalinzu Forest Reserve, Size-Class Distribution, Regeneration Status
JOURNAL NAME:
Open Journal of Forestry,
Vol.5 No.7,
September
21,
2015
ABSTRACT: The
population structure and regeneration status of Trichilia dregeana in heavily and less disturbed habitats of
Kalinzu forest reserve were assessed in 2013. The species was used locally for
medicines, fire wood and making household utensils, a situation that rendered
it vulnerable. Given this dependence by local communities, the population of
the species was under human pressure due to demand. This necessitated a
critical understanding of how the population structure was affected by such
disturbance although in some species, population structure disturbance increased
resilience. Size-class distribution and regeneration status were used to
determine the population structure as influenced by human disturbance. Four
plots of 20 × 10 m were randomly established in each forest type and all T. dregeana trees of diameter ≥ 10 cm
were counted and their DBH was measured at 1.3 m from the ground. In each of
these plots, a 10 × 10 m plot was made and saplings DBH ≥ 2 - 10 cm were enumerated.
Inside each 10 × 10 m plot, a 5 × 5 m plot was made and T. dregeana seedlings (T. dregeana in the heavily disturbed forest was higher than in the less disturbed forest
type. The size-class distribution exhibited a characteristic inverse J-shaped
distribution pattern in the heavily disturbed forest whereas it was bell-shaped
in the less disturbed forest type. In both forest types, the population of T. dregeana was found to be actively
regenerating. This study concludes that the population structure of Trichilia dregeana is dominated by
juveniles with total absence of individuals of DBH ≥ 22 cm, due to selective
harvesting of mature individuals. In order to stop harvesting of this species
from the natural forest, there should be an effort to provide seedlings to
local communities so that they grow it on their farms.