• 항공우주의학회지
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• 제30권2호
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• pp.75-79
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• 2020

This study focuses on the comparative and quantitative analysis of the epidemiologic trends and aspects of severe fever with thrombocytopenia syndrome (SFTS) outbreaks between Korea and Japan from 2013 to 2017. The following factors were analyzed; cumulative incidence rate (CIR), cases-fatality rate (CFR), and the epidemic aspects, including cases related to gender, male-to-female morbidity ratio (MFMR), age, seasonal, and geographical distributions. We observed 607 SFTS cases with CIR in Korea during the period 2013 to 2017 were as 0.24 per 100,000 populations and with a 127 fatal-cases (F.C.s), corresponding to a CFR of 20.9%, respectively. During the same period in Japan, 319 SFTS cases with a CIR of 0.05 and with 60 F.C.s to a CFR of 18.8% observed. When compared, the CIR of SFTS in Korea was significantly higher than in Japan (P<0.01), but there were no significant differences levels of the CFR and MFMR between Korea and Japan. Also, a higher incidence of SFTS was observed in people aged over 50-years or elders in Korea and those of 60-years or elders in Japan (P<0.01). The seasonal distribution of SFTS outbreak cases showed that the incidence in summer through autumn in Korea (92.4% of total cases) was higher than in Japan (65.2%), while the outbreaks of SFTS in spring was much higher in Japan (31.0%) than in Korea (7.4%), (P<0.01). The regional distribution revealed no significant difference between the eastern area (44.8%) and the western area (46.8%) of the Korean peninsula except Jeju-island (8.4%). However, in Japan, the incidence only occurred in Chubu-Kinki-Chugoku (30.3%), Shikoku (25.7%), Kyushu (42.6%) and Okinawa (0.3%), which are the western and southern areas of Japan. These differences in SFTS occurrence may reflect the influences of vector/hosts, climate, and geographical and cultural characteristics between the two countries.

• 환경생물
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• 제37권3호
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• pp.268-277
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• 2019

Severe damages will result in human society, when several different critical natural phenomena coincide. One example relates to the resting cysts of Alexandrium species (dinoflagellates that cause paralytic shellfish poisoning), which are preserved in surface sediments throughout Osaka Bay, Japan. These cysts have been found to accumulate particularly densely in shallow areas in the inner parts of Osaka Bay, where a tsunami caused by an earthquake could occur any time. Damage by a tsunami could cause a change of the coastal ecosystems at Osaka Bay including the resuspension of surface sediments containing resting Alexandrium tamarense cysts and the subsequent redistribution of the cysts in newly deposited sediment. Under certain environmental conditions, these cysts could germinate and form dense blooms, leading to paralytic shellfish poisoning. Such a scenario could also affect other coastal areas, including the southern coast of the Korean Peninsula.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 추계학술발표회
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• pp.167-174
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• 2003

Oceanic conditions of the Tsushirm Wann Current (1WC) region in the southern area if the East Sea (the Japan Sea) are examined using data obtained from a CREAMS (Circulation Research if the East Asian Marginal Seas) cruise in June 1996. In 1990s, a lower temperature appears in $19\%$ and in this period, two branch of the TWC exist and the first branch of the TWC flows inshore if the Japanese coastal region compared to tfr1t in the other years, especially in the sfr1llower water layer at less th:1n about 2mm. The TWC cored with the higher salinity (>34.6 psu) is clearly observed over the continental shelf zone in the Japanese coastal region and offshore and identified by geostrophic calculation Intrusion if the TWC into the East Sea through the Korea Strait (the Tsushima Strait) makes the density structure in the water column change and the water mass in the TWC region is unstable based on Brunt- Vaisala frequency.

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.295-301
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• 2011

We investigated the genetic structure of Korean and Japanese ayu Plecoglossus altivelis populations by examining 669 individuals from 14 populations using three microsatellite loci. Genetic variation did not differ significantly among the populations examined in terms of allelic number and heterozygosity. Korean populations were genetically close to each other, implying that persistent gene flow has occurred in these populations. This suggests that eastern populations in Korea form a single large population and all of the Korean populations are distinct from the Japanese populations. Pairwise population $F_{ST}$ estimates, principal component analyses, and a neighbor-joining tree showed that genetic separation between the southern and pooled eastern coast populations was probably influenced by restricted gene flow. Hierarchical analysis of molecular variance (AMOVA) revealed a weak but significant genetic structure among three ayu groups (eastern and southern coasts of Korea and the Japan coast), and no genetic variation within groups. The estimated genetic population structure and potential applications of microsatellite markers may aid in the proper management of ayu populations.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 추계수산관련학회 공동학술대회발표요지집
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• pp.243-243
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• 2000

There are a large number of researches concerning about artificial reefs in Japan, and many Japanese companies have developed and specialized in the coastal engineering in recent years. Various shape, size and material of artificial reefs are constructed, however, concrete and steel structures are popular material in Japan. Five kinds of artificial reefs were put down on gravel bottoms 5-10 m deep in February 1999, which is located 100 m off Ikata, Shikoku, southern part of Japan. (omitted)

• ALGAE
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• 제36권1호
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• pp.13-24
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• 2021

The present-day genetic structure of macroalgal species reflects both geographical history and oceanic circulation patterns as well as anthropogenic introduction across native ranges. To precisely understand the genetic diversity and how the factors shape the current population structure of Gloiopeltis furcata sensu lato, we determined the mitochondrial 5' end of cytochrome c oxidase subunit I (COI-5P) sequences for 677 individuals sampled from 67 sites spanning almost the entire distribution range in Korea and Japan. Results from the phylogenetic analysis and haplotype distribution revealed eleven distinct lineages within G. furcata s.l. along the Korea-Japan coastal areas and displayed divergent phylogeographic patterns among lineages. Despite the closely related lineages distributed in same habitats as high rocky intertidal zone, they display different phylogeographic patterns among lineages. The populations from the south of Korea-Japan harbored the highest genetic diversity and unique endemism in comparison with other populations in the distribution range. This could be the evidence of southern refugia for G. furcata s.l. in the Northwest (NW) Pacific and the recent migration from native to introduced region. The reason is that an exceptional distribution pattern was found high genetic diversity in Hakodate of Japan where is the northern location in the NW Pacific. Our results imply the contemporary influence on the distribution due to current circulation pattern and anthropogenic effects. These phylogeographic findings provide the important insight into cryptic species diversity and the detailed distribution pattern of Gloiopeltis in the NW Pacific.

• Journal of Ecology and Environment
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• 제44권1호
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• pp.33-40
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• 2020

Background: Understanding the geographical distribution of a species is a key component of studying its ecology, evolution, and conservation. Although Schlegel's Japanese gecko (Gekko japonicus) is widely distributed in Northeast Asia, its distribution has not been studied in detail. We predicted the present and future distribution of G. japonicus across China, Japan, and Korea based on 19 climatic and 5 environmental variables using the maximum entropy (MaxEnt) species distribution model. Results: Present time major suitable habitats for G. japonicus, having greater than 0.55 probability of presence (threshold based on the average predicted probability of the presence records), are located at coastal and inland cities of China; western, southern, and northern coasts of Kyushu and Honshu in Japan; and southern coastal cities of Korea. Japan contained 69.3% of the suitable habitats, followed by China (27.1%) and Korea (4.2%). Temperature seasonality (66.5% of permutation importance) was the most important predictor of the distribution. Future distributions according to two climate change scenarios predicted that by 2070, and overall suitable habitats would decrease compared to the present habitats by 18.4% (scenario RCP 4.5) and 10.4% (scenario RCP 8.5). In contrast to these overall trends, range expansions are expected in inland areas of China and southern parts of Korea. Conclusions: Suitable habitats predicted for G. japonicus are currently located in coastal cities of Japan, China, and Korea, as well as in isolated patches of inland China. Due to climate change, suitable habitats are expected to shrink along coastlines, particularly at the coastal-edge of climate change zones. Overall, our results provide essential distribution range information for future ecological studies of G. japonicus across its distribution range.

• Ocean and Polar Research
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• 제23권4호
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• pp.425-431
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• 2001

From an ecological point of view, the western part of the Atlantic sector is one of the most productive areas in the Southern Ocean. Antarctic krill (Euphausia superba) and krill-dependent predators such as fish, seals, and birds are abundant there, and most krill fisheries have operated in this area since 1970s. The hottest issues for the proper management of krill resources nowadays are to determine total biomass in this area, and to identify environmental forces controlling stock fluctuation. This paper reviews and collates information on ongoing oceanographic activities in the Antarctic Peninsula region concerning these issues. To delineate the status and function of Antarctic krill population in Antarctic marine ecosystems, multinational researches along the Antarctic Peninsula area have been developing recently. Four member states of CCAMLR (Japan, Russia, UK, and USA) had conducted acoustic surveys in January-February 2000 (socalled CCAMLR-2000 survey), and krill standing stock at 120 kHz was estimated to be 44.29 million metric tonnes in the western Atlantic sector of the Southern Ocean. On the other hand, the Southern Ocean GLOBEC (SO-GLOBEC) Programme has prepared a serial winter survey to examine the factors that govern krill survivorship and distribution in relation to shelf circulation processes. Ship-based surveys using ice-breakers are being conducted by three nations (Germany, UK, and USA) around the Marguerite Bay during the austral fall and winter 2001 and 2002. In addition to these two large-scale surveys, some CCAMLR members have carried out joint oceanographic surveys near the South Shetland Islands to detect ecosystem changes since 1994. Especially from December 1999 to February 2000, in conjunction with CCAMLR-2000 survey, four nations (Japan, Korea, Peru, and USA) conducted acoustic surveys to produce time-series information on krill distribution and biomass near the South Shetland areas. Though the aims of each program and the approach to solve the scientific questions were different each other, the results from each program fill the gaps between programs. Further cooperation and exchange in these activities could be beneficial to each program.

• The Korean Journal of Ecology
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• 제23권5호
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• pp.383-389
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• 2000

한국과 일본의 해안사구에서 발달하고 있는 해안사구관목식생인 순비기나무군강에 대한 비교 연구가 수행되었다. 본 연구는 한국과 일본의 해안사구에서 조사된 569개의 균질한 releve를 이용하였다. 또한, 본 연구는 Z.-M. 방법에 의해 추출된 한국과 일본의 순비기나무군강의 각 단위식생과 식물사회학적 체계를 이용하였으며, 군락분류, 군락생태, 군락동태 및 군락지리에 대한 비교 분석으로 이루어졌다. 한국과 일본의 해안사구관목군락은 동북아시아의 남방형 해안사구관목군락을 대표하는 순비기나무군강에 귀속되었다. 그리고 한국과 일본의 순비기나무군강의 해안사구관목군락은 서로 대응관계를 나타내면서도 각각 고유의 군락을 포함하고 있는 것으로 밝혀졌다. 또한, 일본 순비기나무군강의 해안사구관목군락은 한국의 그것에 비해 식생단위 및 종조성에 있어 매우 다양함과 풍부함을 내포하고 있다.

• 한국해양학회지
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• 제8권1호
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• pp.33-45
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• 1973

1967년 3월과 8월 쿠로시오 국제 합동조사의 일환으로 채집한 부유생물 시료로서 동물성 부유생물의 양적분포, 특히 35군에 대한 개체수출현조성을 고찰하였다. 1. 현존량(습중량, mg/㎥)은 해역별 및 시기별로 각기 농도를 달리하고 있다. 3월은 동해남부해역이 30-400mg/㎥, 평균 130mg/㎥로서 가장 풍부한 곳이며 제주도 서방과 서해측은 대부분 50mg/㎥이하로서 농도가 가장 빈약하였다. 8월은 3월과 대조적으로 제주도 서남방 및 서해측과 남해 연안측이 20-1,060mg/㎥, 평균 약 130mg/㎥로서 가장 생산성이 높은 해역이나 동해쪽은 비교적 희소한 편이었다. 소라도 근해는 전기간 풍부하고 서해측은 3월은 연안에 8월은 외양이 더욱 풍부했고 난류주류역은 희소한 편이었다. 2. 35개군의 개체수 출현상황은 해역별 및 시기별 농도가 습중량의 것과 비슷한 경향임을 알수 있다. 3월은 동해남부 해역이 230-1,240mg/㎥, 평균 750mg/㎥로서 가장 풍부한 곳이며, 제주도 서방 및 서해역은 평균 200mg/㎥ 정도로서 희소한 곳이었다. 8월은 난류 주류역을 제외한 남해연안측과 제주도 서남방이 140-3,180mg/㎥, 평균 약 850mg/㎥로서 가장 생산성이 높은 곳이며, 동해측은 약 500mg/㎥로서 빈약한 편이었다. 3. 주요군별 개체수의 출현조성은 요각류가 3월에 69%, 8월에 58% 차지하는 지배적인 군이며, 다른군들은 해역별 시기별로 조성률의 순위가 다소 상이하나 대체로 3월은 유우파우시아류, 관해파리류, 모악류, 미충류 순이고 8월은 모악류, 지각류, 미충류, 유우파우시아류, 관해파리류 순으로 조성되어 있다. 해역별 조성상의 큰차이를 볼 수 있는 곳은 서해오 ㅏ동해남부 해역으로서 전자는 타 해역에서 압도적인 요각류가 8월에 42%정도 뿐이고 반면 지각류와 모악류가 특히 농밀히 조성되어 있으며 후자는 관해파리와 유우파우시아류가 많았다.의 압축강와 흡수율과의 관계는 후라이애쉬를 제외하면 다른 재령에서와 같이 흡수율이 적을수록 압축강도는 증가되며 회기직선관계가 성립되었다. 그러나 후라이애쉬는 장기강도에서 그 특징이 현저히 나타나고 있어 다른 콘크리트의 흡수율에 비하여 현저히 높은 강도를 나타내고 있다. (7) 부식율에 있어서는 1년간 해수작용을 받었을 때 각 콘크리트의 유의적인 부식율이 인정될 수 없으며 외관상에서도 부식현상을 식별할 수 없었다.대에 따라 3개의 유형으로 나눌 수 있으며 총 개의 유형으로 분류하였다. 이런 분류의 토대위에 향후 필요분야마다 구분이 가능한 기후특성을 포함시킨다면 최종적으로는 모든 것이 해설될 수 있는 유역군으로 만들 수 있을 것이다. 즉, 토양특징, 농업특징, 기후특징에 비점오염가능성 등 토지이용상 문제점등을 포괄한다면 다양한 자연현상을 기술할 수 있는 효과적인 유역군이 될 것이다. 별변화가 없으나 황색종, Turker종 및 재래종은 파기가 늦어짐에 따라 낮아지고 이는 파종기에 따른 엽장과 엽폭의 신전율이 종류에 따라 차가 있기 때문이다. 9. 품질은 Turkey종이 가장 높고 황색종 음건종, 재래종의 순이고 또 황색종은 2-3파기 Turkey종은 1파기, 음건종은 3파기의 것이 가장 양질이였으나 재래종은 파기에 따른 변동이 별로 없었다. 그러므로 질과 양을 함께 고려하면 황색종 및 음건종은 3파기가 적기이고 재래종은 3-4파기이나 향끽미료인 Turkey종은 질에 중점을 둔다면 1-2파기가 파기적기라고 볼수 있다. 일반적으로 품질은 책장조직의 발달이 좋고 세포간극률이 낮으며 세엽형인 것이 양질로 판정되나 종류에 따라 차가 있다. 10. 전알카로이드는 Turkey종이 낮고 황색종, 음건종, 재래종의 순으로 높다. 향끽미용인 Turkey종 및 황색종은 파기가 지연됨에 따라 증가하나 음건종 및 재래종은 감소된다. 이에 수반하여 함질화합물도 Turkey종이 가장 적고 다음이 황색종,