Attached
The natural regeneration of woody perennial species under
Pinus caribaea plantation in Yagirala Forest Reserve was
studied. This Reserve is in the wet zone lowland evergreen
forest type in sri Lanka. In this study, naturally
occurring woody perennials were observed in a 1.8 hectare
permanent sample block of unthinned 22 year old pine
plantation. A 10 by 10 metre grid system, which will also
be used for management purposes and which will form the
basis of a Geographic Information system (GIS) database,
was in place. The natural forest was selectively logged
and the area now plantation was clear felled before
planting. This caused considerable change in the floristic
composition of the surrounding forest. Each individual
woody perennial on the 1.8 hectare block having dbh>= 1 cm
was entered into a database and its relative position
recorded on a location map which also included all pine
trees. 1206 stems of pine were found on the 1.8 ha block
(670 stems per ha and 19.72 m2 of basal area per ha). Also, 51 species belong to 42 genera and 24 families were
found giving a total of 1252 individual woody perennial
observations (696 stems per ha and 5.07 m2 of basal area per
ha, excluding pine). Herbarium specimens were collected
for all species using standard methods. Species
composition analysis and Importance Value Index were
determined. It was shown that there is very little
correlation between the frequencies and basal area of pine
and other species. The probable source of regeneration and
seed dispersal methods of the species were studied. The
most abundant tree species were dispersed by wind and
birds. It is shown that this pine plantation has a diverse
and dense floristic composition.
