Relation of the quality of seawater to the decline of seaweed populations

采用连续培养的双环生长情况评价海水水质。当补充培养基中添加50.4 μM以上的硝酸盐、2.8 μM以上的磷酸盐和0.069 μM以上的Fe-EDTA时，在4周的试验期内没有出现营养缺乏对生长的抑制。将鱼饲料颗粒悬浮液连续加入到连续培养系统中，供应培养基含有100 μM硝酸盐、2.84 μM磷酸盐和0.28 μM Fe-EDTA。E.即使在60 mg/1 L供应培养基的最低浓度下，双环也被显著抑制。

The quality of seawater was evaluated by the growth of Eisenia bicyclis cultured in a continuous culture system. When more than 50.4 μM nitrate, more than 2.8 μM phosphate and more than 0.069 μM Fe-EDTA were added in the supply medium, growth inhibition by nutrient deficiency did not occur during the experiment period of 4 weeks. A suspension of fish feed pellet was continuously added to the continuous culture system with the supply medium containing 100 μM nitrate, 2.84 μM phosphate and 0.28 μM Fe-EDTA. The growth of E. bicyclis was conspicuously inhibited even at the lowest concentration of 60 mg per 1 L of the supply medium.