Utilization of Biological Activities of Capitellid Polychaete for Treatmentof "Hedoro" (Organically Enriched Sediment) Deposited on the MarineBottom below Fish Net Pen Culture.

stably around the initial level throughout the period of the experiments for 60 days, while the levels in the experiments without Capitella gradually increased.The promotion of organic decomposition of the sediment in the experiments with Capitella also prevented the develop ment of reduced conditions in the sediment.If we can re-establish a dense Capitella popula tion on the bottom below the fish net pen quickly in the environmental recovery process from autumn to winter by releasing artificially cultured colonies of the worms, the potential of organic decomposition on the bottom will be significantly enhanced.