울산 태화강 하구에 서식하는 바지락 유생의 출현 양상

Abstract

This research for the occurrence patterns of Ruditapes philippinarum larvae were investigated at six stations located at estuaries of Taehwa River, Ulsan. The larvae were collected from June to December 2009 and from June to November 2010. The range of water temperatures was 11.4~26.5 ℃ in 2009 and 16.2~30.4 ℃ in 2010. The changes in salinities were shown 20~36 PSU in 2009 and 5~36 PSU in 2010. During the study period, early D-shaped larvae appeared consistently. The maximum number of Ruditapes philppinarum larvae was 28,088 inds./100ℓ in 2009 and 7,073 inds./100ℓ in 2010 at station 4. The peaks of numbers of larvae were found in 4 terms of the research: early September 2009, mid October 2009, July 2010, and October 2010. The maximum number of clams was 1,430 inds./㎡ in 2009 at station 4 and 1,610 inds./㎡ in 2010.