• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.4
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• pp.438-447
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• 2024

Tongyeong is an important shellfish harvesting area, that hosts the largest designated sea area for shellfish exports in South Korea. In particular, the Dosan-Poonghwa Sea Area in Tongyeong is a semi-enclosed bay with poor water circulation and significant pollution due to its proximity to urban areas. This study examined the distribution of fecal pollution indicators (total coliforms, fecal coliforms, male-specific coliphages, and norovirus G1/G2) in the influent and effluent of wastewater treatment plants (WWTP). This study assessed the impact of the effluent discharge on shellfish harvesting areas in the Dosan-Poonghwa Sea Area to better safeguard shellfish farms and guarantee the safety of harvested shellfish. A strong positive correlation was observed between total and fecal coliforms in both influent (r=0.974, P<0.01) and effluent (r=0.779, P<0.05), with no other significant correlations observed. The impacts of the effluent was evaluated according to NSSP guidelines. The volume of seawater required to dilute the effluent discharged per day was calculated. This evaluation indicated that surrounding aquaculture areas were not impacted, and no viruses were detected in oysters collected from the Dosan-Pungwha Sea Area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.3
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• pp.163-170
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• 2009

Several species of the genus Pseudo-nitzschia produce the neurotoxin domoic acid (DA) known to be responsible for amnesic shellfish poisoning. In spite of the potentially toxic effects on marine ecosystem, even the representative Pseudo-nitzschia species occurring in Korean coastal waters have not been clearly reported. Plankton samples from several outer coastal sites of Tongyeong were collected fortnightly from May to November 2008 and the presence of diatoms of the genus Pseudo-nitzschia was examined using light and scanning electron microscopy. Thirteen species were observed, including P. americana, P. brasiliana, P. caciantha, P. calliantha, P. cuspidata, P. delicatissima, P. micropora, P. multiseries, P. multistriata, P. pseudodelicatissima, P. pungens, P. subfraudulenta, and P. subpacifica. The number of Pseudo-nitzschia species observed were only four in May, which was minimum during this survey, and then gradually increased attaining maximum, twelve, in September. After September it began to decrease again and got to five in November. Of these, P. americana, P. brasiliana, P. caciantha, P. calliantha, P. micropora, and P, pseudodelicatissima are new records for the Korean coastal waters and P. calliantha, P. cuspidata, P. delicatissima, P multiseries, P. multistriata, and P. pungens have been reported as DA producers around the world, but the potential toxicity of these species was not ascertained in Tongyeong area.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.63-63
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• 2004

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.67-67
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• 2004

• Animal Systematics, Evolution and Diversity
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• v.25 no.1
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• pp.137-139
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• 2009

Marine sponges were collected from Tongyeong yachtschool harbor, Korea in 2008. Among them Halichondria (Halichondria) bowerbanki Burton, 1930 is newly recorded in the Korean fauna.

• ALGAE
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• v.26 no.3
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• pp.237-241
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• 2011

The toxic dinoflagellate Karlodinium veneficum has been implicated in numerous fish kill events around the world. Since this species commonly co-occurs with other morphologically similar dinoflagellates, field monitoring of this species in natural waters via light microscopy only has been problematic. In this study, we investigated temporal changes in K. veneficum's abundance in the waters of Obido, Tongyeong, using a species-specific real-time polymerase chain reaction (PCR) assay. The field survey, from April to December 2010, revealed K. veneficum occurred at low densities (12 to 425 cells $L^{-1}$) during this time and that cell numbers peaked in June (early summer in Korea), indicating this species generally occurs in the warmer season (mostly at $16.9-22.3^{\circ}C$ and 33.4-34.5‰) in the Obido area.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.869-877
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• 2017

The monthly variations of zooplankton community were investigated at 12 stations near Tongyeong and Namhaedo in the South Sea of Korea from April to July, 2012. Zooplankton samples were collected by a plankton net (RN80) from near the bottom to the surface. Zooplankton community consisted of 97 taxa, and the mean abundance ranged from $213inds.m^{-3}$ in July to $426inds.m^{-3}$ in April. Copepods constituted 38.98% of zooplankton abundance, and included 39 species. Calanus sinicus, Corycaeus affinis, Paracalanus parvus s.l., copepodids, Evadne nordmonni, Podon leuckarti, cirriped nauplii, Muggiacea sp., Diphyes sp., and Zonosagitta bedoti were dominant species. Of these, Calanus sinicus was the most abundant throughout the study period, being constituted 18.6% of total zooplankton abundance. The density variations of dominant species between stations and months were correlated with the environmental factors. Zooplankton community varied with by sampling months, being influenced by monthly oceanographic variations.

• Journal of Aquaculture
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• v.6 no.1
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• pp.47-53
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• 1993

Feeding trials were conducted for a test of the optimum dietary protein levels for the fingerling Korean catfish, Parasilurus asotus. The growth response was examined in terms of weight gain, feed coefficient. protein efficiency ratio and net protein utilization for 8 weeks at $23\~27^{\circ}C$. Within a range of 25 to 55\%$ crude protein levels in the diet, the body weight increased while the dietary protein level increased. Accumulation of protein in the body reached the maximum when the crude protein level in the diet was at $45\%$. These results indicate that the optimum dietary protein level of fingerling Korean catfish was about $45\%$ when anchovy meal was used as the protein source.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.366-371
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• 2011

The sea squirt Halocynthia roretzi is mainly cultured in Tongyeong, Southern coastal area of Korea. This study presents the physiological rates of respiration, excretion, feeding and assimilation efficiency of the sea squirt Halocynthia roretzi to analyze the SFG(scope for growth) and net growth efficiency, determined during 2007. Oxygen consumption and nitrogen excretion rates increased with a rise in temperature during the summer period whereas feeding rates decreased. The O:N ratio was high during winter(October to February). Assimilation efficiency showed an annual average of 75.4% during the experimental period, except during a period of elevated temperature in July to September(average $25^{\circ}C$). Net growth efficiency($K_2$) was 8.7 to 64.2% except for May to September, when temperature increased at the aquaculture farm. SFG was negative from May to September, reflecting high temperatures and low feeding rates during this period; its highest positive values occurred during winter.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.3
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• pp.278-285
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• 2018

Monthly variation in species composition of fishes in the eelgrass bed of Jangpyeong in Tongyeong, Korea was determined using monthly samples from a seine net from May 2016 to April 2017. A total of 32 species, 2,042 individuals and 3,991.1 g of fishes were collected during the study period. The dominant species were Takifugu niphobles, Rudarius ercodes, Gymnogobius heptacanthus, Zoarchias glaber, Pholis nebulosi and Leucopsarion petersii. These species accounted for 79.5% of the total number of individuals. The fish assemblages in the eelgrass bed showed clear seasonal changes: the number of fish species increased in March and was highest in October, while the number of individuals increased in December and was highest in July.