被覆物質에 의한 低質로 부터 有機物 및 營養鹽類 溶出抑制效果

Abstract

To improve the polluted sediment of coastal shellfish and finish growing area, the study was carried out during 4 months from December 1991. We investigated effects or restorative materials(oyster shells, kaoline, bentionite and lime) on the transudation of organic matter or nutrients from sediment in the laboratory experiment of water tank. Temporal variations of pH weren’t apparent, pH values were lower than that of natural seawater except in the lime coating test container where pH and the releasing rate of calcium were very high. In coating experiment by restorative materials(oyster shell materials), old oyster(middle) had a good inhibitory effect on DO consumption, but the inhibitory effect of organic matter and nutrients releasing rate were not appeared. When old oyster(small) was coated, DO consumption and organic matter were not inhibited, and releasing rate of nutrients were not reduced. In the case of subtracting the releasing rate of self-production from coating materials, DO consumption and releasing rate of organic matter were inhibited and releasing rate of phosphate much more inhibited. When sediment coated by kaoline and bentonite materials, the inhibitory effects of releasing nutrients were apparent and organic matter was not appeared. Lime had a good inhibitory effect for DO consumption and nutrients releasing rate except for ammonia, although pH and COD value were high.