AND FLORISTIC COMPOSITION OF GANNORUWA FOREST.
Udayani R Weerasinghe*
P Jayasekara* and W Dissanayake**
* National Herbarium; ** Forest Department
Gannoruwa forest is a remnant forest patch of about 267 hectares situated
in Kandy district close to the Royal Botanical Garden, Peradeniya.
Plots (of 50 m by 5 m) were laid out at regular intervals along environmental
gradients in order to sample the full range of floral diversity from lowest
levels to ridge tops. All the woody plants above 10 cm girth at breast
height (G.B.H.) within plots were enumerated and other smaller woody species
(shrubs, herbs, seedling and saplings) were noted. Floristic structure;
density, basal area and height and floristic composition; floristic richness
and density dominance of woody flora were evaluated to gather scientific
guidelines and baseline information of the study site.
The vegetation of the area is dominated by lowland evergreen mixed vegetation.
So far more than 110 species have been recorded in different girth classes.
At the upper elevation, girth sizes and basal area were higher than at
the lower elevation. As a result of human habitation of the lower area,
the natural forest has been degraded to a larger extent. Some areas of
the Gannoruwa forest were relatively little disturbed and contain old
massive trees. A high percent of basal area is mainly contributed by native
taxa in these areas. Some of these are Artocarpus nobilis, Mangifera zeylanica,
Nothopegia beddomei, Neolitsea cassia, Pometia tomentosa, Diospyros racemosa,
Hydnocarpus venenata and Myristica dactyloides. Some exotics; Michelia
champaca, Alstonia macrophylla and Swietenia macrophylla were also found
in this area.
It is evident that Gannoruwa forest provides a natural refugium as in-situ
conservation for many native endemic species. Also it acts as a natural
buffer in disease outbreaks and as a habitat for pollinating and dispersing
agents for the surrounding area and Royal Botanic Gardens. If Gannoruwa
can be protected as a natural reserve it would be a valuable educational
site. Students can compare both ex-situ conservation area (Royal Botanical
Gardens) with natural in-situ conservation Gannoruwa forest. This study
Department of Forestry and Environmental Science,
of Sri Jayewardenepura,Sri Lanka. 1999. All rights reserved.