• Animal Systematics, Evolution and Diversity
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• 제32권4호
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• pp.272-280
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• 2016

Most scyphomedusae jellyfishes recorded in Korean waters are temperate and subtropical species. In the present study, two cold-water jellyfishes from Korean waters are first described. Scyphomedusae were collected from the coasts of Gangneung and Ulsan of the East Sea, and Boryeong, and the eastern area of the Yellow Sea from June 2006 to May 2015. Scyphomedusae collected in Ulsan and Gangneung were identified morphologically as Aurelia limbata Brandt, 1835. Their umbrella was 250-500 mm in width and 30-50 mm in height; the exumbrella was white and the subumbrella was dark brown in color. The vascular system was complex with anastomosed branches. Individuals of this species lived at about 6.6-9.9℃ and 30-50 m depth in Korean waters. Scyphomedusae collected from the center of the Yellow Sea and from Boryeong were identified as Parumbrosa polylobata Kishinouye, 1910. Their umbrella was disc-shaped, 80-200 mm in width and 20-40 mm in height. Its milky white gonads could be seen through the transparent exumbrella. The stomach cavity was round and flat with four interradial cavities connected by subgenital cavities, and the four oral arms were bifurcated and spear-head shaped. Individuals were found at about 6.4-10.0℃ and 40-90 m depth in Korean waters. The identities of both species were confirmed by molecular analysis using nuclear ribosomal DNA sequences.

• 한국수산과학회지
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• 제41권2호
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• pp.119-124
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• 2008

Reproductive ecology of the snow crab Chionoecetes opilio was investigated in terms of the reproductive organs, abdominal flap, fecundity, and maturity. Specimens were collected with gill nets and trawls from June 2002 to May 2003 in the eastern waters of Korea. The female and male C. opilio are distinguished only by the shape of the abdominal flap, which is triangular in males and circular in females. The gonads of female and male crabs are generally X-shaped. The male gonad is white, while the female gonad appears milk-white after spawning and then turns from light orange to dark orange with maturation. The female gonads matured from June, and mature and immature groups could be distinguished from December to February or March. Brooding eggs changed from bright orange to dark brown with formation of the compound eye immediately before hatching. Accordingly, the main spawning season is February and March. The minimum maturity carapace width of female crabs was 61.1 mm, and the mean fecundity is about 108,300 eggs.

• 한국지리정보학회지
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• 제8권4호
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• pp.33-43
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• 2005

중국 대륙연안수(CCW;China Coastal Waters)는 해에 따라 다소 다르지만 보통 하계인 6월~10월 사이에 제주도 주변해역에서 두드러지게 나타난다. 즉 6월에 나타나기 시작하여 8월에 가장 큰 영향을 미치며 10월로 접어들면서 그 세력이 점차 소멸해간다. 해수면편차에 대한 조화분해를 통해서 보면, 제주도 동부해역의 진폭 값(8~9.5cm)이 서부해역의 진폭 값(l3cm 이상)보다 약 5cm 정도 낮았다. 연 위상은 동부해역($267^{\circ}$ : 8월 말)이 서부해역($275^{\circ}$ : 9윌 초)보다 약 $8^{\circ}$정도 빠르게 나타났다. 해수면온도에 대한 조화분해는 제주도 동부해역의 진폭 값($7{\sim}8.5^{\circ}C$)이 서부해역의 진폭 값($5.5{\sim}6^{\circ}C$)보다 약 $2^{\circ}C$ 정도 높은 값을 보였고, 연 위상은 동부해역($242^{\circ}$ : 8월 초)이 서부해역 ($236^{\circ}$ : 7월 말)보다 약 $6^{\circ}$정도 늦게 나타났다. 파워스펙트럼 분석에서 해수면편차와 해수면온도는 모두 연 주기, 반 년 주기, 계절주기가 나타났다. 해수면편차는 1996년, 1998년, 1999년의 여름과 가을이 다른 해보다 높게 나타났는데, 이것은 예년과 다른 강한 집중호우와 밀접한 관계가 있는 것으로 사료된다. 해수면 온도의 계절에 따른 온도분포는 해에 따라 다소 다르지만 황해 해역과 동지나 해역을 구분 짓는 뚜렷한 수온 경계를 이룬다. 이 온도의 경계해역을 따라서 중국대륙연안 수가 흐르는 것으로 사료된다.

• 수산해양기술연구
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• 제53권1호
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• pp.1-11
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• 2017

Fishing pots are one of the important fishing gears in our coastal and offshore fisheries. In terms of a sustainable use of marine resources, there are concerns about the ghost fishing by lost pots. It is reported that 10 to 70% of the pots are abandoned or lost annually. This study is to compare the catching efficiency of drum type whelk pots that are made of biodegradable nets to those made of the ordinary nets, in the eastern coast of Korea. Five types of drum pots were used with combination of biodegradable nets and ordinary (PA, PE) nets applied to the main and funnel parts of the pots: pots with biodegradable nets (Bio+Bio); pots with PE net (PE+PE); pots with body and funnel made of biodegradable nets and PE nets respectively (Bio+PE); pots with body and funnel made of PE nets and PA nets respectively (PE+PA); pots with body and funnel made of PE nets and biodegradable net respectively (PE+Bio). Field experiments were conducted from June $18^{th}$, 2015 to August $7^{th}$, 2015 using a commercial fishing vessel in the Uljin waters on the eastern coast of Korea. Two fleets of pots with one hundred in each, 20 pots of each type, were casted for 8 to 15 days to analyze their catching efficiency. The catch of target species, whelks, was 202,563.0 g with catch rate of 38.7% of the total catch, while the bycatch was 320,709.7 g with the rate of 61.3% of the total catch. The catch of whelks was the highest in the Bio+PE pots (46,020.3 g), followed by the Bio+Bio pots (42,027.5 g), the PE+Bio pots (41,849.9 g) and the lowest being PE+PE pots (38,054.2 g). Compared to the conventional pots, the pots with biodegradable nets on the body or entrance part had slightly higher catch rate for both the target species and the bycatch. The PE+PE had the lowest catch rate. There is no significant difference in catch between the pots with biodegradable nets and the ordinary nets for the target species such as Buccinum opisthoplectum, Neptunea eulimata, Buccinum striatissimum. Consequently, using biodegradable nets for the conventional whelk pots can reduce ghost fishing by lost gears while keeping the performance of the pots.

• 한국해양환경ㆍ에너지학회지
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• 제3권3호
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• pp.13-23
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• 2000

1993년 12원과 1994년 8월 2회에 걸쳐 동중국해 동부해역 관측선 J (30° N)의 용존무기영양염들의 분포에 대해 조사하였다. 고온고염의 특성을 지닌 쿠로시오 표층수의 질산이온 및 규산농도는 각각 2μM 이하와 5μM 이하로 낮다. 반면에 수심이 증가할수록 질산이온 및 규산농도는 급격히 증가하여 쿠로시오 중층수에서는 각각 20～40, 45～100 μM 범위로 높았다. 대륙붕역 저층수와 쿠로시오 중퐁수의 수온과 용존무기영양염 관계는 용존무기영양염이 풍부한 쿠로시오 중층수가 대륙붕수로 관입되고 있음을 암시한다. 수온, 염분 및 규산 농도를 해수추적자로 이용하여 수괴득의 혼합을 분석한 결과, 대륙붕 저층수는 대륙붕단 바로 바깥쪽 수심 약 100～400 m의 쿠로시오 중층수와의 혼합수라는 것이 밝혀졌다. 이와같이 대륙붕단을 따라 대륙사면에서 대륙붕안으로 올라오는 높은 용존무기영양염 농도를 지닌 용승해수는 동중국해 대륙붕역의 식물플랑크톤 일차생산력을 증가시키는 중요한 영양염 공급원으로 사료된다.

• 한국제4기학회지
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• 제17권2호
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• pp.15-15
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• 2003

In South Korea, marine terraces have been well developed along the eastern coastal zone, and previous researches on the marine terraces have also been focused on to this coastal zone. The marine terraces of the eastern coast of South Korea had been classified into three terrace groups, that is, the higher, middle, and lower surface ones, according to the heights of marine terraces by previous studies(Oh, 1981 ;Chang, 1987 ;Yoon et. al, 1999, 2003 ; Hwang and Yoon, 1996 etc.). Recently, however, it tends to classify the marine terraces based on the concept of geomorphic surface units(Lee, 1987 ; Kim, 1990 ; Choi, S. 2003; Choi S. et. al 2003a,b, etc). For example, it was proposed that the marine terrace surfaces of Eupcheon coast of the southeastern coastal area of Korea could be classified into 16 geomorphic surfaces, i.e., Eupcheon 1terrace(former shoreline height of 160m), 2(153m), 3(140m), 4(130m), 5(124m), 6(115m), 7(100m), 8(92m), 9(82m), 10(71m), 11(62m), 12(53m), 13(43m), 14(35m), 15(18m) and 16(10m) surfaces, in descending order, according to the former shoreline heights(Choi, S, 2003 ; Choi, S. et. al, 2003a,b). Among these terraces, Eupcheon 1, 2, 4, 5 and 7 surfaces had not been reported in previous works. Among the above mentioned marine terraces, Eupcheon 15 terrace, the most widely and continuously distributed marine terrace have been identified as marine terrace of the Last Interglacial culmination period(oxygen isotope stage 5e) which was based on amino acid dates(124∼125ka BP) and geomorphological features such as red soil, pollen analysis, fossil cryogenic structures and crossing terrace concept. Eupoheon 15 terrace surfaces have also been proposed as the key surface for the identification and correlation of the so-called '5e' marine terrace in the eastern coast of South Korea. This terrace was reconfirmed as the Last Interglacial culmination period, which was based on the identification of Ata tephra, one of the wide-spread marker tephra which indicates the Last Interglacial culmination period in Japan by Sasaki et. al(2002). It was thought that marine terraces of the eastern coast of South Korea had been formed by the steady-state uplifting during the Quaternary glacio-eustatic sea level changes(Choi, 1997). The uprift rate of 10cm/1,000years had been proposed in the eastern coast of South Korea based on the former shoreline altitude(18m) of the above Eupcheon 15 terrace. Therefore, it can be estimated that Eupcheon 1 terrace had been formed in the early Pleistocene from the above uprift rate. The OSL dating for the samples of Eupcheon 7, 9, 13, 15 and 16 terraces and identification of marker tephra in the terrace deposits are in progress. It is expected that more elaborate chronology on themarine terraces of the eastern coast of South Korea could be established by these absolute dates and marker-tephra.

• 한국관개배수논문집
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• 제10권1호
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• pp.62-72
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• 2003

Tideland reclamation has been known to begin in 13th century in the eastern coast of Ganghwa Island during the Mongolian Invasion in Korea. Traditionally, the tidal reclamation projects have been developed in the coastal with nearly flat inter-tidal zone

• ALGAE
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• 제22권1호
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• pp.23-29
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• 2007

Free-living heterotrophic stramenopile flagellates, which lack chloroplasts, were encountered in deep-sea sediments of Gippsland Basin (Australia) and classified into 10 species (8 genera, 5 families, 3 orders). Their descriptions were based on living specimens by light microscopy. Those species rarely found in this study were Bicosoeca gracilipes, Caecitellus parvulus, Cafeteria minuta, Cafeteria roenbergensis, Pseudobodo tremulans, Spumella sp., Paraphysomonas sp., Actinomonas mirabilis, Ciliophrys infusionum and Developayella elegans. Their morphological characters and geographic distribution are presented.

• 한국지하수토양환경학회지:지하수토양환경
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• 제14권5호
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• pp.1-4
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• 2009

• 환경생물
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• 제33권2호
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• pp.170-176
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• 2015

Oncholaimid nematode, Oncholaimus secundicollis Shimada, Kajihara and Mawatari, 2009, is firstly reported based on a comparative morphological study. The present specimens of O. secundicollis are collected from rocky intertidal seagrass on the eastern coast of Korea. Oncholaimus secundicollis is distinguished from all of its congeners by the following combination of morphological characteristics: buccal cavity large with thick cuticular wall and three teeth, left subventral tooth larger than right subventral or dorsal teeth, and the presence of two remarkable precloacal papillae with nine pairs of cloacal setae and single ventral tail papilla with two pairs of short setae. In this study, we provide taxonomic description and illustration of unrecorded species of the genus Oncholaimus.