西海沿岸의 養殖場 環境調査 3. 扶安 백합 養殖場 環境

Environmental Survey on the Cultivation Ground in the West Coast of Korea 3. Environmental Conditions for Hard Clam Farm in Puan

In puan area the environmental surveys were carried out at two farms of hard clam, Meretrix lusoria from April 1987 to November 1978 in order to know wheather the farm environments could be rehabilitated for the cultivation of hard clam or not. The range of temperature of surface seawater was 10.7~27.4℃. pH 7.6~8.2, salinity 22.3~30.3 ppt, COD 0.20~4.71mg/l, sulfide 0.04~0.22μg-at./ㅣ, suspended solid 34.8-199.3mg/l, chlurophyll a 3.71~49.02mg/m³, TIN 2.01~24.47μg-a5./ㅣ, phosphate 0.60~11,03 μg-at./I, and silicate 4.04~476.36μg-at./ㅣ. The range of temperature ot substratum(bottom soil) was 14.2~29.7℃, pH 8.3~9.5, water content of substratum was 0.28~0.49 mg/g dried mud, COD 2.80~50.94mg/g dried mud, total organic matter 1.05~1.97%, concentration of total Kjedhal nitrogen 31.9~194.9 μg./ㅣ dried mud, and sulfide 0.032~0.133mg/g dried mud. Fine sand was dominant ranging over 92~95% and silt and clay was 2.8~8.1% of the composition of substratum. Some residual agricultural chemicals, α, β, r-BHC. heptachlor, heptachlor-epoxide, aldrin, DDE. DDT and dieldrin were detected in hard clams collected from Puan areas. Especialy, more chemical were detected during the period of rainfalls. From above results, it is considered that the hard clam frams were not yet recovered from deteriorated conditions for aquaculture.