• 한국지구과학회지
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• 제33권4호
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• pp.320-328
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• 2012

후기 홀로세 동안의 지형발달과 기후환경변화를 고찰하기 위해 함평천 유역의 충적평야에서 채취된 퇴적물 시료에 대한 탄소연대측정(AMS, Accelerated Mass Spectrometry), 토양유기탄소와 휴무스분석을 실시하였다. 최하부인 토탄층은 온난 습윤한 기후환경에 형성되었으며, 후빙기 중 Atlantic기에 해당되는 것으로 사료된다. 황갈색 사질점토층은 자연제방성 퇴적물이며, 대체로 온난하고 건조한 기후 환경에서 퇴적된 것으로 생각된다. 그 형성시기는 1,879-1,532 BC 이며, 이 시기는 후빙기 중 Sub-boreal기에 해당된다. 담갈색 점토층은 자연제방에서 배후습지로 이행되는 환경에 퇴적되었을 것으로 추측된다. 기후 환경은 온난하고 습윤하였으며, 후빙기 중 Sub-boreal에서 Sub-Atlantic으로 이행되는 시기에 형성된 것으로 유추된다. 상부의 담황갈색 점토층과 담갈색 점토층은 배후습지의 퇴적물로 생각된다. 담황갈색 점토층이 퇴적된 환경은 냉량하고 습윤한 기후환경이었을 것으로 생각되며, 이 시기는 후빙기 중 Sub-Atlantic에 대비될 가능성이 있다. 담갈색 점토층이 퇴적된 환경은 온난하고 건조한 기후환경이었을 것으로 생각된다. 그 형성 시기는 211-427 AD이며, 이 시기는 Post Roman Warm Period에 해당되는 것으로 유추된다.

• ALGAE
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• 제17권4호
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• pp.203-216
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• 2002

• Ocean Systems Engineering
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• 제1권2호
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• pp.121-130
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• 2011

One of the prevailing models that describe the stress corrosion is represented by an exponential dependence between rate of corrosion and stress, suggested by Gutman, Zainullin and Zuripov. This study revisits the exponential model and derives analytical expressions for the structures' durability which is postulated as the time for stress level to reach its yield value. Comparison is conducted with other possible models, namely with linear, quadratic or cubic cases.

• 한국수산과학회지
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• 제16권3호
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• pp.265-272
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• 1983

Carpogonia, spermatangia and carposporangia are demonstrated for North Atlantic plants of Audouinella alariae (Jonsson) Woelkerling for the first time. The plants are monoecious. Carpogonia are terminal on short branches and give rise to short trichogynes laterally. Spermatangia are usually borne in pairs on the supporting cells of carpogonia. Fertilized carpogonia give rise to 3-4 carposporangia. Morphology of sexual reproductive structures and postfertilization development provide characteristics for distinguishing A. alariae from A. rhipidandra (Rosenvinge) Dixon, which were previously synonymized.

• 한국자원식물학회지
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• 제10권1호
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• pp.11-16
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• 1997

칼슘시비량(施肥量)이 가공용 대서품종(大西品種)의 내부갈색반점발생(內部褐色斑點發生)에 미치는 영향은 다음과 같다. 칼슘시비구가 무처리구(無處理區)에 비해 내부갈색반점(內部褐色斑點) 발생율(發生率)이 상당히 감소 되었으나 칼슘시비구간에는 시비량이 증가할수록 발생율이 감소하는 경향이나 유의성은 없었다 .칼슘시비에 따른 생육상을 보면 발아율(發芽率), 초장(草長), 경수(莖數)등에서는 차이가 없었으나 生草重(生草重)에서는 Ca (200kg/ha)구에서 가장 높게 나타났다. 한편 중심공동율(中心空洞率) 발생율(發生率)은 4처리 모두 16%이상 높은 발생율을 보였으나 칼슘의 영향을 거의 받지 않는것으로 나타났다. 따라서 내부갈색반점(內部褐色斑點) 발생(發生)은 괴경내에의 칼슘결핍과 관계가 있는 것으로 판단되어 대서품종 재배시 칼슘시비를 해야 발생율을 줄일 수 있을 것으로 판단되었다.

• 한국발생생물학회지:발생과생식
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• 제8권1호
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• pp.11-17
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• 2004

북대서양에서 상업 적으로 중요한 해산어류인 Haddock Melanogrammus aeglefinus의 자치 어 발생과정과 성장을 조사하였다. 자치어는 부화 후 67일까지 사육실 조건에서 사육되었고 주기 적으로 표본한 재료를 실체 현미경으로 관찰하였다. 발생단계별 크기 변화는 부화 후부터 지속적인 성장을 보여 Y=4.07 $e^{0.037}$( $R^{2}$=0.9978)의 성장식을 나타내었다. 부화 직후의 자어는 전장 4.9 m로 장방형의 난황을 가지고 있었다. 초기 먹이섭취는 부화 후 7일에 시작되었으나 부화 후 16일 째 전장 6.8 m때에 난황이 완전히 흡수되어 후기 자어 단계가 되었다. 부화 후 16~52일의 기간에 부속기관의 발달이 활발히 진행되었으며, 전장 41.3 mm인 부화 후 61일에 턱수염은 완전히 발달되지는 않았지만 치아, 측선, 체측의 검은 반점 등은 성어와 같은 모습의 치어 단계에 도달하여 본 종은 이 시기 이후로 먹이와 생태적 행동변화가 일어나는 것으로 추정된다.다.

• Journal of Advanced Marine Engineering and Technology
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• 제38권2호
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• pp.208-216
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• 2014

In case of any coastal ocean near the mouth of huge rivers, low salinity water can be formed due to its large amount of freshwater discharge. For the acoustic analysis on the low salinity environment, some oceanographic data of the East China Sea and the Atlantic Ocean were collected through KODC (Korea Oceanographic Data Center) and NODC (National Oceanographic Data Center) online service. In this paper, the T-S gradient diagram is introduced to show a relation between the gradients of temperature and salinity in view of acoustic surface channel formation. Existence of haline channel, quantitative contribution of gradients of salinity and temperature, effectiveness of the channel formation can be known by the T-S gradient diagram. After applying the collected data into the diagram, tropical regions of the Atlantic Ocean show strong haline channel due to its nearly invariant temperature and drastic change of salinity with depth. The averaged transmission loss in the channel is about 5.7 ~ 7.5 dB less than that out of the channel by the results of acoustic propagation model (RAM: Range independent Acoustic Model). On the other hand, the East China Sea and temperate region of the Atlantic ocean have weaker haline channel with less difference of the averaged transmission loss between in and out of the channel as 3.2 ~ 6.0 dB. Although data samples used in this study have limitation to represent the general physical structures of the three ocean regions, the T-S gradient diagram is shown to be useful and acoustic field affected by low salinity environment is investigated in this study.

• 수산해양기술연구
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• 제57권3호
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• pp.194-204
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• 2021

The research was analyzed the catch data of the five years (2016-2020) for six joint venture company tuna purse seiners in the Atlantic Ocean, with the aim of suggesting improvement measures for responsible and sustainable fishing according to changes of recommendation by International Commission for the Conservation of Atlantic Tuna (ICCAT) on the tropical tunas. In the last five years, the average catch of six tuna purse seiner gradually increased to 7,745 tons, 8,364 tons and 9,053 tons from 2016 to 2018, but decreased to 7,761 tons in 2019 and 6,214 tons in 2020. The reason for the decrease in fishing volume in 2019 and 2020 was the fluctuation of the formation of the cold water zone (22-23℃), and the total ICCAT convention area of FAD closure in January and February due to the expansion of the FAD closure area and poor free school catching during two months period, respectively. The analysis on fishing area showed that the percentage of fishing in the high sea was about 85% although the FAD closure area included the EEZ zone in coastal countries; the rise of the fishing license in coastal countries is also believed to be a factor. In order to overcome such situations and improve catching volume, it will be possible if excellent manpower is secured, school fishing is expanded, and the production of high value-added catch (purse seine special: PS).

• Journal of Plant Biotechnology
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• 제42권2호
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• pp.77-82
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• 2015

We found that a long period of in vitro culture is a critical factor on the low transformation rate for a specific potato genotype, Solanum tuberosum L. var. Atlantic when phosphinothricin (PPT) was added to select putative transformants in a solid media. The fresh explants of the newly produced plants from a micro-tuber was able to increase the transformation rate significantly while the old explants prepared from a plant maintained for longer than 6 months in vitro by sub-culturing every 3 ~ 4 weeks resulted in a very low transformation frequency. However, Jowon cultivar was not so much influenced by the period of in vitro culture with high transformation rate (higher than 10.0%). Further research need to be explored for the reason why a particular potato genotype, Atlantic is more vulnerable than the Jowon cultivar during the regeneration stage resulting in the low transformation frequency.

• ALGAE
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• 제26권1호
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• pp.51-60
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• 2011

Similar to other species of Gigartinaceae Chondrus crispus has an alternation of perennial, isomorphic gametophytic and sporophytic generations. As these two generations co-exist independently within populations and obtain their resources in a similar manner, intraspecific competition is expected. In populations within the southern Gulf of St. Lawrence, fronds of both generations of C. crispus occur in similar numbers. This equivalency can be related to substratum instability, where the population is dynamic with a high turn-over rate of genets. These observations support a stochastic hypothesis to account for distribution of gametophytes and sporophytes in this area. Along the Atlantic coast of Nova Scotia, where the substratum is stable, gametophytes are overwhelmingly predominant. Gametophytic predominance is greatest in the lower littoral zone where C. crispus is abundant and space is limited. Under the fucoid canopy where "free-space" exists, the gametophyte to sporophyte ratio is lower. Gametophytic and sporophytic fronds are distributed equally among different size-classes and size-distribution is not considered a competitive factor. Previous studies have shown that sporophytic fronds of C. crispus are more susceptible to infections by endophytic algae and other pathogens, and are more heavily grazed by herbivores than are gametophytic fronds. Thus, mechanistic factors are strongly implied in the selection of gametophytes in the Atlantic population.