• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.175-183
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• 2010

To understand the variation of macro benthos community according to the installation of structure and topographic placement in the shellfish farm on tidal flat, the practical example of the tidal shellfish growing area at Namsung-ri Goheung was observed. The results of the research for the field observation were summarized as follows. (1) The ground gradient of the shellfish farm was very flat below about $1^{\circ}$. The shellfish farm ground took the shape of $\sqcup$ from the shoreline to the place of 150 m seawards, and the shape of $\sqcap$ from there to the low tide line. During ebb tide, the $\sqcup$ shape ground stored the sea water, and the $\sqcap$ shape ground was supposed to act as the effect factor to leak slowly or to prevent the outflow. (2) The oyster shell bag or the type of riprap wall as the boundary in the shellfish farm was classified into five types. The air exposure time and flooding time were 181 and 434 minutes, respectively. (3) In the numerical experiment, the deep-sea water wave coming in the study area had 0.5 m of maximum wave height to show the very stable conditions and the wave direction pattern of S-direction was dominant at Naro great ridge, and SE, SSW and S-direction were distributed strongly around the shellfish farm. (4) By the grain size analysis, the sediment around tidal flat consisted of gravel 0.00~5.81(average 1.70)%, sand 14.15~18.39(average 13.23)%, silt 27.59~47.15(average 30.84)% and clay 35.79~55.73(average 36.19)%, and the sediment type was divided into (g)M(lightly gravelly mud), sM(sandy mud) and gM(gravelly mud) by Folk's diagram. (5) The macro benthos community survey conducted in this site in January, 2010 showed that 1 species of Mollusca, 8 species of Polychaeta and 2 species of Crustacea appeared, and 11 species occupying over 1% of total abundance were dominant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.429-436
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• 1998

A bacteriological study of sea water and oyster in Charan Bay was conducted to evaluate sanitary conditions of the bay and compliance of waters with the recommended bacteriological criteria for the designated area of shellfish cultivation, The Samples were collected at 23 sampling stations(Fig. 1 and Fig. 2) estaslished once a month from January 1997 to December 1997, During the study period, temperature ranged from 4.7 to $25.6^{\circ}C$, transparency ranged from 3.3 to 6.2m chemical oxygen demand ranged from 1.67 to 2.18 mg/$\ell$, dissolved oxygen demand ranged from 5.4 to 10.0 mg/$\ell$ dissolved nitrogen ranged from 1.65 to 7.88 $\mu$g-at/$\ell$, phosphate ranged from 0.15 to 1.16 $\mu$g-at/$\ell$, Chlorophylla-a ranged from 0.95 to 12.69mg/$\ell$. The coliform group and fecal coliform MPN's of sea water were ranged from <1.8$\~$l,600 and <1.8$\~$540, respectively. The coliform group and fecal coliform MPN's of oysters were ranged from <18$\~$16,000 and <18$\~$1,400, respectively. The viable cell counts in oyster ranged from $1.5\times10^2$ to $7.5\times10^3$. The bacteriological criteria of sea water in shellfish growing area should be less than 70 per 100 ml of sea water for median value of coliform MPN, and below $10\%$ of the samples which contain over than 230 for coliform MPN or over than 43 for fecal coliform MPN. The sea water from 432 samples were complied water coliform criteria recommended for designated shellfish growing area. The coliform group, fecal coliform, classification of coliform group with IMViC reactions and pathogenic vibrios were analyzed. During the study period, infectious bacteria such as Vibrio cholerae, Salmonella sp, and Shigella sp, were not detected from the samples, but detection ratios of Vibrio parahaemolyticus and Vibrio vulnifirus were $7\~17\%$ in summer months.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.145-162
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• 1974

시판되는 굴, 담치, 백합 등 패류는 깨끗한 수역에서 생산되어야 한다는 것은 공중보건상 매우 중요하다. 따라서 이들 서식해역에 대한 위생상태를 평가하는 것은 패류위생관리에 있어 가장 기본적인 일이다. 본 조사는 미국 Alabama주 West Fowl River 지역에 있어 패류위생관리상 양식장의 등급분류와 관련한 굴(Crassostrea virginica) 및 그 서식수의 위생학적 성상을 알기 위하여 실시되었다. 이 연구는 미국 국제개발처(AID) 연수계획에 의하여 이루워 졌음을 밝혀 둔다. 조사지역에 있어서의 감염원은 가옥, 소업체, 가축, 물새, 야생동물 등에 의한 일반적인 발기물과 배설물로 되어 있고 특별한 하수나 공업배출물은 없었다. 이 조사는 이 지방에 있어 건조기인 10월에 실시되었으며 조사기간중의 총 강우양은 0.08mm, 평균 기온은 $21.3^{\circ}C$, 바람은 동풍이 우세하였다. 저질은 뻘로 되어 있고 저호시 평균수침은 약 1m이며 조사기관중 평균 수온은 $26.0^{\circ}C$였다. 염분은 조사지점에 따라 상이하였으며 바다로 향한 강의 흐름에 따라 증가하고 평균 염분은 $18.0\~28.7\%$의 범위에 있었다. 해수 및 굴 양자의 Coliform 함양은 Fecal coliform 보다 시종 높았으며 Coliform 및 Fecal coliform의 수는 바다로 향한 강의 흐름에 따라 점차 감소하였다. 이것은 해수의 오염은 주로 지표수의 유입에 의한다는 것을 말하고 있다. 굴의 Coliform 및 Fecal coliform MPN은 해수의 그것보다 $11\~12$배 높았다. 조사수역에 설정한 7개소 Sampling station 중 오직 Station 7만이 패류양식장 허가해역의 세균학적 수질기준에 합당하였으며 굴의 Fecal coliform MPN은 시판용 패류의 세균학적 기준을 초과하고 있었다. EC test 양성시험관에서 분리된 세균의 $97.6\%$가 E. coli group로 나타나 EC test는 Echerichie Coli 시험에 매우 효과적인 방법임을 알 수 있다.

• The Korean Journal of Malacology
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• v.31 no.2
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• pp.129-136
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• 2015

To introduce an oyster rack culture in tidal flat of Wando-gun, Korea, we investigated sanitary conditions from 2012 April to 2013 March in oyster growing waters and adjacent area in Wando. Average seawater temperature and salinity ranged $8.6-28.0^{\circ}C$ and 26.2-33.6 psu, respectively. The coliform group and fecal coliform of seawater ranged < 1.8-13.0 MPN/100 mL each. Only one of 60 samples was exceeded in the European criteria of fecal coliform. Influence of adjunct basin's pollution load on cultural waters was negligible, which half radius of dilution was not above 300 m. According to our observation, however, landing of oyster should be banned for at least 5 days after the heavy rainfall. Our findings meet the sanitary seawater criteria for domestic use and export of shellfish and classified as 'Class A' in European Community regulations for bivalve culture.