• 한국토양비료학회지
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• 제47권4호
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• pp.254-261
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• 2014

The scientific information between microbial activities and chemical properties of reclaimed tidal soil is not enough to apply for reclamation projects. This study was conducted to investigate the relation between chemical properties and microbial activities of reclaimed tidal lands located at western coastal area (25 samples from Nampo, Ewon, Sukmoon and Shihwa sites). Most of the reclaimed soils showed chemical characteristics as salinity soil except Nampo site. The major component influenced the salinity of reclaimed soil was identified as a sodium from the relationship between EC and exchangeable cation. With an increase in EC of soil, the population of mesophilic bacteria decreases whereas halotolerant and halophilic bacteria increases. The population of mesophilic bacteria increased with an increase in both organic matter and dehydrogenase activity. However, the population of halotolerant and halophilic bacteria decreased with an increase in organic matter. Based on the relation between chemical property and microbial activity of reclaimed tidal soil, electrical conductivity and organic matter as chemical properties of soil, population of mesophilic bacteria, halotolerant and halophilic bacteria and dehydrogenase activity as microbial activities could be the major parameters for reclamation process.

• 한국환경과학회지
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• 제10권3호
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• pp.209-216
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• 2001

Dustfall particles were collected by the modified American dust jar (wide inlet bottle type) at 6 sampling sites in Pusan area from March, 1999 to February, 2000. Thirteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Si, and Zn) were analyzed by AAS and ICP. The purposes of this study were to estimate qualitatively various bulk deposition flux of dustfall and insoluble components by applying regional and seasonal distribution. Dustfall amount of regional variations were found in order of coastal zone, industrial zone, commercial zone, agricultural zone and residential zone, and seasonal total dustfall had higher concentrations during spring for 6.741 ton/${km}^2$/season, lower concentrations during summer for 1.989 ton/${km}^2$/season, and annual total concentration was 17.742 ton/${km}^2$/year. The regional distributions of enrichment factor show well-defined anthropogenic metals (Cd, Cu, Pb, and Zn) at industrial and agricultural zone, and contribution rate of soil particles were found in order of summer, fall, winter and spring. Factor loading effects of chemical composition of dustfall were found in order of road traffic emission source and combustion processed source, industrial activity source, soil source and marine source.

• 한국환경과학회지
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• 제15권7호
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• pp.689-694
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• 2006

To examine inshore radioactive contamination caused by nuclear power plants, nuclear testing, hospital and laboratory, both gross ${\beta}$-radioactivity and ${\upsilon}$-spectrometry were measured. The measurements were taken with the Abalone and Top shell, which had been collected from the four different sites at the coast in Jeju-do (Seongsan, Deajeong, Wimi, Dodu). The activity ranges of concentration were respectively 0.11-0.29 Bq/kg-wet for $^{90}Sr$, 0.01-0.04 Bq/kg-wet for $^{137}Cs$, 36 - 53 Bq/kg-wet for $^{40}K$ in shellfish on the Jeju island. The radioactivities of $^{90}Sr$, $^{137}Cs$ and $^{40}K$ were similar to those in sampling location of shellfish in the coastal on the Jeju island. The radioactivity of $^{90}Sr$ for the Abalone was lower level than that for Top shell. The radio- activity of $^{137}Cs$ for the Abalone was similar to that for the Top shell. But the radioactivity of $^{40}K$ for the Abalone was higher level than that for the Top shell. As a result, the gross ${\beta}$-radioactivity observed was similar to that in nature. Among radionuclides, only $^{90}Sr$, $^{137}Cs$ and $^{40}K$ were detected in a very small amount, and each was also close to the natural levels.

• 한국토양비료학회지
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• 제48권4호
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• pp.262-270
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• 2015

The scientific information between microbial community and chemical properties of reclaimed tidal soil is not enough to understand the land reclamation process. This study was conducted to investigate the relation between chemical properties and microbial activities of soils from reclaimed tidal lands located at south-western coastal area (42 samples from Goheuong, Samsan, Bojun, Kunnae, Hwaong and Yeongsangang sites). Most of the reclaimed soils showed chemical characteristics as salinity soil based on EC. Only $Na^+$ in exchangeable cation was dependent on EC of reclaimed soil, whereas other cations such as $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were independent on EC. The mesophilic bacteria decreased with an increase in EC of soil. Microbial population increased with soil organic content in the range of $0{\sim}10g\;kg^{-1}$ and dehydrogenase activity less than $100{\mu}g-TPF\;g^{-1}h^{-1}$. Microbial population of soils from reclaimed tidal lands was closely related to the microbial community containing hydrolytic enzyme activities of cellulase, amylase, protease, and lipase.

• 한국환경생태학회지
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• 제32권5호
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• pp.478-485
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• 2018

저어새(Platalea minor)는 세계자연보전연맹(IUCN)에서 발표한 RedList에 Endangered(EN)로 지정되어 있으며, 2016년 기준으로 3,356개체가 생존하는 것으로 알려지고 있다. 또한 저어새 번식 개체군의 70% 이상은 한국 서해안에서 번식하며, 대만, 중국, 홍콩 등지에서 월동하는 것으로 알려져 있으나 한국을 비롯하여 동아시아 지역에서 저어새의 장거리 이동과 남하 시 서식지에 대한 연구는 현재까지 거의 이루어지지 않은 실정이다. 이 연구에서는 야생동물위치추적기(WT-200, GPS-Mobile phone based telemetry, KoEco)를 이용하여 저어새의 이동 경로와 분포, 중간기착지 및 월동지를 밝히고자 하였다. 위치추적기는 2014년 6월 말 한국의 번식지에서 저어새 유조를 포획하여 부착했다. 추적 결과, 저어새의 남하시기는 10월 말에서 11월 초로 나타났으며, 월동지까지의 이동 거리는 최소 746km, 최대 1,820 km로 평균 1,201 km이었다. 하루 최대 이동 거리는 1,479 km이었으며, 평균 782 km이었다. 월동지까지 이동소요 기간은 평균 10일이었으며, 가장 짧은 기간은 2일이었고 가장 긴 기간은 34일이었다. 대부분의 개체들은 2~3개의 중간기착지를 이용하였으며, 1~2일을 머물렀으며, 주요 중간기착지는 강, 하천, 저수지, 갯벌과 같은 습지였다. 월동지는 중국 해안 지역(5개체), 중국 내륙 지역(1개체), 대만(3개체), 일본(1개체)등 으로 나타났다. 결론적으로 저어새의 이동경로 상에 있는 국가 간의 협의와 보호정책을 통해 이들이 주로 이용하는 중간기착지 및 월동지역을 보전할 필요가 있으며, 향후 지속적인 모니터링과 추가연구를 통해 체계적인 보전대책 및 활동계획 등이 수립되어야 할 것으로 판단된다.

• 한국어병학회지
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• 제34권1호
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• pp.63-70
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• 2021

As a part of research to elucidate the pathogenesis of so called Soft Tunic Syndrome(STS), that caused mass mortalities in the cultured sea squirts, Halocynthia roretzi, the epidemiological and pathological analysis were done to both clinically normal and diseased groups of the farms of Tongyoung and Geoje coastal areas in southeast sea from February to July, 2008. In the histological finding of the tunic, most of individuals showed tunic softness syndromes that included the disarrangement and destruction of tunic fiber with the simultaneous presence of flagellates-like cells, recently suspected as main agents of tunic softness syndromes. Simultaneously, the intensive degenerative changes of the skeletal muscle of diseased sea squirts were recognized. The changes were characterized with the hyalinization and condensation of muscle fibril and hemocytic infiltration in the muscle fibers. Those were thought to be a kind of typical Zenker's necrosis as in the skeletal muscle of higher vertebrates. Besides of the diseased sea squirts, Zenker's necrosis of skeletal muscles were seen in the normal ones. Epidemiological inquiry for diseased groups revealed that the higher incidences of tunic softness syndrome were recorded in the fast growing groups and in the sites presuming the organic pollution. And Higher malondialadehyde(MDA) and glutathione peroxidase(GPx) activity were detected in the groups showing STS. Those results suggested that Zenker's necrosis of body muscles was a kind of"nutritional myopathy" by oxidative stress. Conclusively, it was considered that Zenker's necrosis of body muscles gives an important clue for elucidating pathogenesis of STS of cultured squirts. And it seems that the necrosis were caused by the oxidative stress to body muscle during abnormal rapid growth of sea squirts.

• 한국어병학회지
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• 제36권2호
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• pp.277-286
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• 2023

Korean rockfish, Sebastes schlegelii, is a representative bony fish that belongs to the family Scorpaenidae and the order Scorpaeniformes. It has high ecological and economic value and is widely cultivated in many East Asian countries, including South Korea, Japan and China. One of streptococci, Streptococcus iniae, is Gram-positive cocci with a negative reaction for catalase and oxidase. The Korean rockfish shows clinical signs when infected with S. iniae, such as body darkening, bleeding, enlarged kidneys, blurred eyes, abdominal distension, etc., ultimately leading to death. The Korean rockfish causes significant economic losses every year in South Korea due to streptococcosis. In this study, we identified bacteria from the fish using polymerase chain reaction and conducted analyses of hemolytic activity and biochemical tests using API 20 STREP and API ZYM systems. Results of confirming the hemolytic activity (n=4) observed in alpha-type hemolysis (25%), beta-type hemol- ysis (50%), and gamma-type hemolysis (25%) of isolates. The biochemical test results exhibited sig- nificant variation among S. iniae. Additionally, we performed intraperitoneal injection with S. iniae in the fish and analyzed the phylogenetic tree using housekeeping genes of S. iniae, including cpsD, arcC, glnA, groEL, gyrB, mutS, pheT, prkC, rpoB, and tkt, via multilocus sequence typing (MLST). The lethal dose (LD₅₀) showed strong pathogenicity, such as 3.34 × 10 colony-forming unit (CFU)/ml for 23FBStr0601 strain and 7.16 × 10 CFU/ml for 23FBStr0602 strain. 23FBStr0603 strain showed relatively low pathogenicity at 1.73 × 10⁵ CFU/ml. The strains 23FBStr0601 and 23FBStr0602, which showed strong pathogenicity, clustered into one monophyletic group. The 23FBStr0603 strain showed weak pathogenicity and formed a monophyletic group with KCTC 3657.

• 해양환경안전학회지
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• 제26권2호
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• pp.175-185
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• 2020

본 연구는 부산시 기장군 연안의 춘계 해조 군집 특성을 파악하고자 수행하였다. 연구는 2017년 5월부터 6월까지 스쿠버 다이빙(scuba diving)을 이용하여 정량 및 정성 조사를 실시하였다. 연구 결과 녹조류 13종(10.7 %), 갈조류 18종(14.9 %), 홍조류 90종(74.4 %) 등 총 121종의 해조류가 출현하였고, 조간대에서 총 56종, 조하대에서 총 110종으로 조하대 출현종이 2배가량 많았으며, 해역별로는 문동 88종, 공수 76종, 대변 75종 순으로 높았다. 연구 해역의 평균 생물량은 1,501.5 g·m^-2로 확인되었으며, 조간대 1,133.5 g·m^-2, 조하대 1,869.4 g·m^-2로 조하대가 더 높았고, 해역별로는 문동 2,234.0 g·m^-2, 공수 1,228.1 g·m^-2, 대변 1,044.4 g·m^-2 순으로 높았다. 높은 생물량을 나타낸 종은 조간대에서 Ulva australis, Sargassum thunbergii, Corallina pilulifera, 조하대에서 Sargassum macrocarpum, Undaria pinnatifida, Phycodrys fimbriata로 확인되었다. 해조류 기능형군별 피도 비율에 따라 군집 상태를 분석한 결과 연구 해역 전체는 'Low', 집단별로는 'Low' ~ 'Moderate' 상태를 나타내었고, 이는 기회종(opportunistic species)이 기장 해역 전체에 걸쳐 폭넓게 분포하고 있는 것을 나타내기 때문에 교란이나 환경오염 등의 문제가 고려된다. 특히 기장 해역은 해조류 양식이 주를 이루고 있어 양식장 조성과 국가어항개발 및 연안 정비 등의 연안개발로 인한 인위적인 영향이 해조 군집에 지속적인 영향을 미칠 것으로 생각되며, 해역 전반에 걸친 해조 군집의 장기 모니터링과 우수한 해조 군집에 대한 관리 방안이 필요할 것으로 판단된다.

• 생명과학회지
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• 제22권5호
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• pp.642-649
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• 2012

남해연안지역은 피조개($Scapharca$ $broughtonii$) 양식으로 매우 중요한 지역이나 최근 대량폐사로 인하여 생산량이 급격히 감소하였다. 이러한 대량폐사의 원인을 구명하기 위하여 다양한 환경요인들에 대한 연구는 수행되었으나, 미생물학적인 연구는 미비한 실정이다. 본 연구에서는 폐사율이 높은 강진만과 폐사발생이 적은 진해만 연안 피조개 양식장의 해저 퇴적물과 피조개 체내에서 분리한 미생물 균총에 대하여 분석하였다. 각각의 샘플에서 배양 가능한 모든 미생물을 분리하였으며, 분리한 미생물 중 알파 또는 베타 용혈활성을 보이는 미생물을 모두 동정하였다. 피조개 체내에 존재하는 용혈미생물의 균총은 해저 퇴적물 보다 낮은 다양성을 보였으며, 극히 한정된 종의 미생물이 존재함을 알 수 있었다. 강진만에서는 17속(genus) 88종(species)의 미생물을, 그리고 진해만에서는 16속 64종의 미생물을 분리할 수 있었다. 샘플 내에는 $Bacillus$ 속의 미생물이 가장 많이 분리 되었으며, 그 중 $Bacillus$ cereus group의 종이 가장 많고, $Paenibacillus$, $Lynsilbacillus$, 그리고 $Vibrio$ 종 등이 그 다음으로 많이 존재하였다. 속(genus) 수준에서는 두 지역의 특별한 차이를 발견할 수 없었으나, 진해만 연안에서는 64종이 발견되었고 강진만에서는 88종이 분리되어, 강진만이 좀 더 종 수준에서의 높은 다양성을 알 수 있었다. 따라서 피조개 대량폐사의 원인은 이러한 균주의 종 수준에서의 차이에서 기인하는 것 이라고 가정할 수 있었으며, 폐사지역에서 발견되는 미생물을 이용한 감염실험을 통하여 피조개의 대량폐사 원인 균을 구명 할 예정이다.