GROUND HERBACEOUS FLORA IN UNLOGGED SITES OF SINHARAJA WORLD HERITAGE SITE

Abstract

The composition and distribution of herbaceous plants were investigated at SinharajaWorld Heritage site.

Previously unlogged torest areas were selected for the present study. Several transects weremarked purposively in each site from valley to ridge to study the topographical variation ofherbaceous plant distribution. Circular plots. each 10 m" were demarcated on each transectto study the herbaceous flora. In addition. 200 m2 plots surrounding the 10m2 plot weremarked to enumerate the tree species in the area. The distance between two. 200 1112 plotswas 20 m.

In each plot number of plant species was recorded, Voucher specimens were prepared foridentification of species found in plots as well as outside thc riots. Dominance diversitycurves and Shannon diversity indices were prepared for each transect.

Ninety one species belonging to 40 families were recorded. Twenty nine of 9 I species areround outside plots. The estimation of individuals of herbaceous plants per hectare was21.790. Herhs and herbaceous climbers represented 38.47% of the total herbaceous flora.Fern and fern allies represented 45.67(1,: and grasses and sedges 15),4%. respectively.

Species rich families were Zingibcraccac (6 spp.) and Ruhiaceac (5 spp.) Densitydominance families were Rubiaccuc (6.97%) Zingibcraceae (3.9%). Mysinaccac 0.6%),Polipodiaceae (17Y1c,). Dennestaediaccac (7.8%) Cyatheaceae 0.8%) and Cypcraaccae(5.5%). Diversity indices in valley and ridge were 0.2153 and 0.1754. respectively.

Results indicate the localised distrihution of herbaceous species in understory vegetation oflowland rain forest. This may he due to the differences in micro habitats from valley toridge.