Abstract:
The fatty acid composition in the tissue of Anadara ova/is from Setiu lagoon, Terengganu
in September and October was compared with those in sediment and suspended
particulate material (SPM) in order to determine the avaibility of food source in
environment. Microalgae ( diatom and dinoflagellate) contribute to the main food source
of bivalve diet with high mean percentage in tissue during both months (44.75 - 53.83%).
High mean percentage of microalgae in sediment suggests that the microalgae likely
obtain by bivalve from the sediment resuspended in water column near the bottom
surface. Copepod marker (20: 1 ro9) abundance in the tissue of bivalve contribute to the
food source of bivalve beside microalgae. A. ovalis live in the intertidal flat nearby
mangrove area. The fatty acid 18: 1 ro9, 18:2ro6 and 18:3ro3 found in the tissue indicate the
consumption of mangrove detritus derived from adjacent area. The bacteria (18:lro7 and
odd-branch fatty acid) which attached to mangrove detritus also contribute to the food
source of bivalve but only small in number (2.49 - 5.13%). The macroalgae marker
(18:2ro6 and 18:3ro3) also present in tissue but small in number. A viability of macroalgae
at the mangrove area is limited due to low intensity of light. Therefore, the present of
these fatty acids in the tissue of bivalve (2.48-3.75%) could indicate other food source
such as the seagrass detritus.
