ESTIMATION OF OXYGEN-CONSUMPTION OF A DEPOSIT-FEEDING POLYCHAETE CAPITELLA SP I

Attempts to re-establish dense colonies of a deposit-feeding polychaet e, Capitella sp. I for promoting the organic decomposition of organica lly polluted marine sediment below fish net pen culture need more info rmation on the oxygen consumption characteristics of the worms. In thi s study, the oxygen consumption characteristics of Capitella colonies have been examined in laboratory conditions by using a method consisti ng of measuring the depletions of dissolved oxygen concentrations ([O2 ]; mg O2/l) over the reconstituted sediment cores containing a given n umber of active adult Capitella. Oxygen uptake rate (OUR) of the worms (ca. 20,000 individuals/m2) was calculated and expressed as an oxygen flux (mg O2/m2.h). Worm OUR was found to be a function of [O2] and ca n be characterized by OUR = 14.45 + 36.75 log[O2], under an constant t emperature of 21 +/- 1-degrees-C. Compared to other benthic oxygen con sumption data, respiratory activities of Capitella colonies were sligh tly low. During oxygen depletion periods, the worms have revealed an a bility to adapt well. Moreover, they still survived for several days a lthough ambient [O2] was beneath 0.3-0.5 mg O2/l. These results demons trated that Capitella has appropriate abilities to be utilized as an e ffective biological treatment for poorly oxygenated sediment below fis h net pen culture areas.