Abstract:
Southern coastal belt in Sri Lanka is characterized by unique ecosystems
providing secure habitats for intertidal floral and faunal communities.
Biodiversity assessment of these communities is important for recognizing
ecosystem changes in coastal environment prior to implementing
management and conservation programmes. A biodiversity survey on the
intertidal invertebrates and macroalgae along this coastal belt was carried
out using systematic aligned sampling method. The sampling was made
from the uppermost part to low waterline of the intertidal zone at 12
selected beaches (i.e. Hambantota, Godawaya, Rekawa, Tangalle,
Dickwella, Polhena, Mirissa, Weligama, Unawatuna, Galle fort,
Dodanduwa and Hikkaduwa) covering 3 Districts (Hambantota, Matara,
Galle) along the coastline during July-October 2018. The sampling sites
were selected by preliminary investigation considering commercial
importance such as the recreational and fishery activities. According to the
results, Shannon-Wiener diversity index (H') ranged from 1.61 to 2.86.
Biodiversity of the respective ecosystem is spatially varied significantly
(p<0.05). Overall results indicated 44 species belonging to Phylum
Arthropoda, Mollusca, Echinodermata, Coelenterata, Porifera, Division
Chlorophyta, Rhodophyta and Phaeophyta. Macroinvertebrates in Phylum
Mollusca (> 50% of species richness) and macroalgae in Division
Chlorophyta (> 16% of species richness) dominated the invertebrate and
algal components of the intertidal community respectively. The findings of
the current study could be used as baseline data when implementing coastal
conservation programmes along the Southern coastal region.
