Abstract

In order to figure out the characteristic of the occurrence of manila clam seeds and its inhabited environment in the mid-south of West coast, investigated at 19 manila clam beds on April and August, 2013. Water environment were shown to be changed depend on time of investigation rather than geographical effect. Sediment quality were under reference value which means it is uncontaminated. Regarding the sedimentary environment, sedimentary facies of the surface deposit were as various as eight, with a higher tendency of coarse-grained deposit in the contents of gravel, sand, silt, and clay. The average exposure time of the manila clam farms was 1 hour and 55 minutes. At the 10-20 mm habitat density of seed clams, no seed clams were harvested in April at Dangmi, Jukyo, Rahang, and Beopsan, which showed a typical phenomenon where seed clams grew and increased in number in August. On the contrary, Doseong, Wangsan, and Daecheon showed the opposite results where more seed clams were harvested in April than August, presumably because the habitat density of seed clams was too high in the previous year to delay growth. More seed clams developed in the sedimentary environments with coarse sizes of average deposit particles, mixed with other particles of various sizes.