Factors Influencing Distribution Of Larvae Of Arkshell, Anadara broughtonii (Schrenck)

피조개 유생의 분포에 영향을 미치는 몇가지 환경요인에 대하여

This work concerns ecological studies on the larvae of the ark shell, Anadara broughtonii(SCHRENCK), in the aea adjacent to Gajyo-do in Jinhae Bay. Marine environmental factors, namely, temperatue, salinity, depth, and tidal current were observed in connection with the larval distributions. Water temperature appeared to be one of the main factors that influence the spawning activity. The numbers of the drifting larvae fluctuated greatly during the study period. The trend, however, was for numbers to be low in early summern, increasing in mid summer, and reaching a peak in late summer, at high bottom water temperature and low bottom salinities. Significantly increased numbers of the drifting larvae were observed during the period in which the bottom water temperatures and salinities were very close to those at the surface. the numbers of the drifting larvae showed a positive relationship with velocities of the water mass within the range of 0∼20 cm/sec. It was also noticed that the drifting larvae were relatively abundant in the area of eddy motion.

피조개, Anadara broughtonii(SCHRENCK)는 근년에 와서 산업적 가치가 높아짐에 따라 중요 양식대상종으로 많은 연구의 대상이 되고 있다. 인공 및 천연채묘에 관해서는 관야91963), 이등 외(1967), 금정 외(1969), 전중(1971)등의 연구와 중간양성에 관해서는 관야 외91966)의 연구가 보고되고 있으며 유91969, 1970)는 먹이 및 성장에 관해서 보고한 바 있다. 본고에서는 피조개의 산란 및 유생의 출현상황과 분표에 영향을 미칠것으로 추측되는 몇가지 환경요인을 관찰하여 검토한 결과를 보고한다.