천수만 방조제 건설 후 대천 해빈 천해 어류의 중장기 종조성 변화

Abstract

Species composition of fish in the shallow water at Daecheon beach was determined using monthly beach seine samples collected from April 2010 to March 2011. These data were compared with the previous data, one just after reclamation in 1984–1985, and the other in 1995–96, in order to assess the post-reclamation impact of the environmental change on the fish assemblage. A total of 30 species from 1,464 individuals with biomass of 17,808 g were identified. Dominant species in the number of individuals were Chelon haematocheilus (49.3%), Takifugu niphobles (13.7%) and Paralichthys olivaceus (10.0%). Among pelagic fish, migrant juvenile fish such as Sardinella zunasi and Thryssa kammalensis were abundantly collected in 1984–85, but the catch amount was gradually decreased as time untill only few pelagic fish were collected in 2010–2011. The benthic fish were most abundant in 1984–1985 among habitat groups, and Favonigobius gymnauchen and Kareius bicoloratus were the top two predominants. Species composition of benthic fish did not exhibited drastic changes in 1995–1996, but both the abundance decline and the species composition change was evident in 2010–2011. Among the semi-benthic fish from 1984–1985 samples, Sillago japonica and Konosirus punctatus predominated. Species composition was slightly changed in 1995–1996, but significant changes were met in 2010–2011 with the two predominats, Chelon haematocheilus and Takifufuniphobles. These changes in fish species composition may reflect the post-reclamation effect of the impaired water quality and the accumulation of organic rich fine sediments.