• 수산해양기술연구
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• 제50권4호
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• pp.567-582
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• 2014

Coastal fisheries in Korean waters have highly complexity with a variety of fishing gears, and scale of those fisheries is smaller than that of offshore fisheries. As a result, important spawning and nursery grounds for many species of fish has been destroyed. The pragmatic ecosystem-based approach was developed for the assessment of fisheries resources in Korean waters by Zhang et al. (2009; 2010). As for the species risk index (SRI), common squid caught by coastal gillnet in the Uljin region had the highest risk. As for the fisheries risk index (FRI), coastal gillnet in the Uljin coastal waters had the highest risk. For the common squid which had the highest SRI, resources management strategies must be established such as catch prohibition of length and period with TAC. For the coastal gillnet in the Uljin region which had the highest FRI, it is judged to need management plans for conserving biodiversity as reducing the catch of non-target species and discards. Also to protect existing habitat, illegal fishery should be prohibited, and fishing gears should be designed in the environmental-friendly way considering when fishing gears lost.

• Ocean and Polar Research
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• 제39권4호
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• pp.257-267
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• 2017

Although Pacific mackerel (Scomber japonicus) is an important commercial species in Korea, its recruitment mechanism remains largely unknown. Diel vertical positioning of larvae in the water column, which is affected by their specific gravity and the surrounding water density, may help to provide an understanding on recruitment success through predator avoidance and prey availability. The specific gravity measurement on Pacific mackerel eggs and larvae would seem to be essential information necessary to learn about the transport process from spawning to nursery grounds, and consequently the recruitment success. Eggs were artificially fertilized, and larvae were fed with rotifer when their mouths opened 3-4 days after hatching. We conducted the experiment using a density gradient water column to measure the ontogenetic changes in specific gravity from fertilization to 10 days after hatching. Egg specific gravity was stable during most of the embryonic period, but a sudden increase to $1.0249g\;cm^{-3}$ happened just before hatching. However, the specific gravity of newly hatched larvae was much lighter ($1.0195g\;cm^{-3}$), and specific gravity tended to increase continuously after hatching. Comparison of specific gravity with seawater density reveals that eggs and newly hatched larvae can float in the surface layer of the ocean. For the later period of the experiment, the specific gravity showed a cyclic diel pattern: the highest in the evening while the lowest at dawn. The fullness of larval stomach may be responsible for the observed differences in specific gravity, because stomach fullness was lower (40-60%) at midnight, and higher (80-85%) in evening. The diel pattern of specific gravity might provide clues regarding how larvae match the diel vertical migration of prey organisms.

• 한국패류학회지
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• 제28권3호
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• pp.259-267
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• 2012

Due to the oil spill incident in December 2007, every facility of oyster culture was removed in western coast especially in Taean and Seosan. To restore oyster resources in Taean and Seosan, we brought oyster seeds from southern area and monitored their growth. In addition we monitored the culture environment throughout the year, and observed the number of oyster larvae and attached spats on collectors during summer. The factors of water environment were appropriate for oyster culture in both study area. The growth of shell height was larger in Uihang-ri, Taean than Jungwang-ri, Seosan. Spawning was more intensive in a short time in Jungwang-ri, Seosan than Uihang-ri, Taean. The number of oyster larvae and spats of collectors were much more in Jungwang-ri, Seosan than Uihang-ri, Taean. This study showed that transplantation of healthy oyster seeds from southern area can be a way of restoration of oyster resources in western coast. In addition, systematic approaches are necessary by building a better understanding of regional characteristics to restore and enlarge the oyster culture farms in western coast. In summary Uihang-ri, Taean will be appropriate for cultivation farms and Jungwang-ri, Seosan for seedling grounds to increase oyster culture productivity.

• Journal of Ecology and Environment
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• 제38권2호
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• pp.241-247
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• 2015

A participatory approach of local stakeholders is important to create a balance between nature protection and the sustainable use of natural resources in a nature reserve and its vicinity area. The zoning and management policy of biosphere reserves (BRs) is a good example of this idea, especially for island reserves. Yakushima was inscribed as a World Natural Heritage (WH) in 1993. Almost all of its residents did not remember that Yakushima was a BR. In addition, Yakushima has some problems in nature reserve management. Overabundance of the deer population is a critical threat to both agriculture and natural vegetation in the world heritage site. There are too many tourists visiting the WH site and Nagata-hama beach. The beach is a Ramsar site and one of the most important spawning grounds of sea turtles in the north Pacific. Now, residents and the municipality have decided to reactivate the Yakushima BR. Although the Ministry of the Environment of Japan has an initiative to manage the WH and the Ramsar site, the BR is managed by the municipality and local stakeholders. Local activities of both nature conservation and the sustainable use of natural resources are encouraged in the BR site. The islanders willingly included all areas of the island into the BR site. Scientists who have participated in the Society of Yakushimaology have played a significant role to build trust between local stakeholders and to seek feasible policies on the nature reserves. The concept of the "Yakushima Environmental Culture Village" is a good model for the extension plan of the Yakushima and Kuchinoerabujima BRs.

• 한국수산과학회지
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• 제47권6호
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• pp.888-894
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• 2014

Seventeen specimens of leptocephali [9.8-44.5 mm total length (TL)], of the family Ophichthidae, were collected from southeastern waters off Jeju Island and the Korea-Japan intermediate zone, and identified by means of morphology and genetics. These specimens were identified as belonging to the subfamily Ophichthinae based on various combinations of morphological characters: 211-215 total myomeres; 7 gut swellings; 2 liver lobes connected with the gall bladder on the second lobe; 6-7 postanal pigments present from anus to caudal margin. An analysis of the partial 12S rRNA sequences (849 base pairs) of mitochondrial DNA showed that our specimens must be Ophisurus macrorhynchos because their sequences were concordant with those of the adult O. macrorhynchos (genetic distance = 0.000). Furthermore, their total myomeres were consistent with those of the O. macrorhynchos adult. This is the first time that the morphological characteristics of O. macrorhynchos leptocephali have been described for Korean waters, and we suggest diagnostic characteristics for the genus Ophisurus leptocephali. We hypothesize that one of the spawning grounds of O. macrorhynchos is located in the southeastern part of Jeju Island.

• 한국조경학회지
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• 제23권1호
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• pp.51-65
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• 1995

Conservation of the natural environiment In chosun-Dynasty, Korea, is analysed on the basis of the of official records of the king's offices(Chosun-wangjo-sillok). In the popular ideologies of the dynasty, Seongleehak(philosophy of humanity arid natural laws) and Pungsu (geomancy) , the naturnal enviroment is defined as an entity con-sisting of Cheon (heaven) , San(mnountains) , Su (water), Geumsu (animals)and Chomok (plants) .the notion of Tacksi-Tackmul(being careful to take natural resources at the right time) was one of the Cheonmyung (eavenly decrees) . It was believed that violation of this principle resulted in natural disasters. Sasan(four mountains surrounding Hansungbu-, the capital city, now Seoul) , were strictly preserved according to geomancy practices. In areas other than the capital city, Sanlimcheontack (mountains, forests, rivers and ponds) were con-served for sustained production of building materials especially pinetrees for ship building, foods, firewoods, horses, and orter useful natural resources. Various conservation policy insturuments were adopted. Prunning trees was permitted only in October. Capturing fishes was allowed only after the spawning period. Protection areas were designated in Sasan, Seongjoesiplee (surroundings of the capital city) , Geumsan(protected mountains), Kangmujang(hunting and army training grounds), Sijang(firewood areas), Mokmajang(horse ranches) and Neungyuk(royal tombs) . Activities prohibited for conservation purposes included cutting timbers, burning, building houses or tombs, dumping wastes, farming and breaking up fresh land, grazing, hunting and trespassing. Positive actions for conservation were rituals to Heaven ennoblement of natural elements such as mountians or rivers, planting trees, Boto (supplementing soil on low ridges) , Josan (mounding) and making ponds. Boto, Josan and making ponds were to make ideal terrains for geomancy. Many government bodies and civil servants were engaged in the conservation activities. For example, Sanjik(forest keeper) was a special position with responsibility for forest management.

• 대한조선학회논문집
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• 제31권1호
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• pp.22-31
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• 1994

해양 공간에 설치되어 유체의 흐름과 지형에 변화를 주며, 대상 수산 생물의 유집에 의한 생산 어장의 조성과 치어의 보호 육성을 도모하는 중효한 어장 시설인 인공어초의 기술 개발은 점차 다양화되어지고 있다. 부체부와 계류부로 구성되어 있는 부어초의 개발에 있어서는 부어초의 특성 및 안전상 계류시스템의 설계가 극히 중요한 부분이 된다. 이 논문에서는 부어초의 계류시스템에 많이 사용되어지는 나일론, 폴리에스터와 폴리에틸렌으로 이루어진 인조섬유로우프의 정적시험의 과정과 그 결과로서의 Creep거동 및 하중-인장 곡선을 얻었다. 특히 나일론 로우프의 경우 수중에서 20%내외의 강도 하락(Strength drop)이 관찰되며, Creep 시험 곡선은 대수시간 축(longerithmic time axis)상에서 직선을 유지하고, Flessner's formula와 평행한 결과를 얻었다.

• 한국수산과학회지
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• 제55권2호
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• pp.154-170
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• 2022

The zooplankton composition, abundance, community structure, and species diversity in the major commercial fishery species spawning grounds in the southern coast of Korea were investigated in this study. A total of 80 taxa were sampled, with the mean abundance range of 5,612-11,720 ind. m^-3 and the mean biomass range of 41.6-1,086.8 mg m^-3. The dominant species were Paracalanus copepodites, Paracalanus parvus s. l., Oithona copepodites, Paracalanus nauplii, Noctiluca scintillans, Oithona similis, and Ditrichocorycaeus affinis. The species diversity indices were highest in August, suggesting that diversity is influenced by neritic and oceanic warm-water species. A cluster analysis with non-metric multidimensional scaling (nMDS) revealed three groups of zooplankton communities. The April and May samples clustered into Group A, having the highest mean total zooplankton abundance and lowest species diversity, consisting mainly of temperate species located in the middle region of the southern coast of Korea. Cluster Group B was from the early summer season (June) and contained the highest species diversity with some oceanic and neritic zooplankton species. Cluster Group C from the summer season (July and August) mainly comprised P. parvus s. l. and O. similis. The redundancy analysis (RDA) indicated that abundance is positively correlated with salinity, and chlorophyll-a concentrations.

• Ecology and Resilient Infrastructure
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• 제3권1호
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• pp.62-69
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• 2016

맹꽁이는 Kaloula 속에 속하는 양서류로는 우리나라에서 유일하게 한 종이 서식하고 있으며 멸종위기야생생물 II 급으로 지정, 관리하고 있어 맹꽁이의 절멸 방지를 위해서는 맹꽁이에 대한 서식처 복원 연구가 절실히 필요하다. 본 연구는 훼손된 맹꽁이 서식처 복원이나 대체서식지와 같은 새로운 맹꽁이 서식처 복원 시 바람직한 생태적 복원 방향을 제시하기 위하여 연구 대상지인 전라남도 목포시에 맹꽁이 서식처 적합성 지수 (HSI)를 활용 및 실제 적용하여 맹꽁이 서식처 복원 계획을 제시하는 것을 주된 목적으로 하였다. 연구대상지의 역사적 맥락, 생태기반환경, 생태환경, 맹꽁이의 서식처 요구 조건 등을 분석한 후 UNESCO MAB (Man and Biosphere) 공간구획에 따라 연구 대상지를 핵심, 완충, 전이지역으로 토지이용 계획을 수립하였다. 기본계획으로 맹꽁이 서식처인 핵심지역에 대한 구체적인 맹꽁이 서식처 조성방안을 습지 (산란처), 초지 (은신처 및 먹이터), 수림대 (먹이터)로 구분하여 제시하고 서식처 계획 전, 후의 맹꽁이 서식처 적합도를 비교 평가하였다. 향후 맹꽁이 서식처 복원 계획에 따른 검증 연구로 테스트베드 (test-bed) 조성, 지속적인 모니터링, 과학적인 서식처 유지 관리에 대한 연구가 이루어져야 한다.

• 수산해양기술연구
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• 제48권4호
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• pp.452-468
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• 2012

한강 하구 해역에서 2010년 4월부터 2011년 11월까지 총 9회에 걸쳐 출현한 생물은 5 분류군 61과 126종이었다. 갑각류는 18과 34종, 두족류는 3과 5종, 어류는 35과 79종으로 분류되었으며, 그 외 종단위로 분류되지 않은 자포동물류인 해파리류와 포유류에 속하는 상괭이가 출현하였다. 한강 하구 해역의 출현종의 대부분은 어류와 갑각류로 구성되었다. 연구기간동안 주된 우점 종은 그라비새우, 꽃게, 밀새우, 갯가재 등이었으며, 어류로는 웅어와 싱어이었다. 우점한 6종에 대한 체장조성 및 평균체장을 살펴보면, 하나 이상의 체장모드를 가지는 것으로 나타났다. 하나 이상의 모드를 가지는 것은 한강 해역에 출현하는 종들이 일정시기 또는 일생동안 한강 하구 해역에서 서식하며, 산란장 또는 성육장으로 이용하고 있다는 것을 반영한다. 한강 하구 해역중 강과 가장 가까운 정점인 더리미에서는 민물어류가 출현하였으며, 홍수 등 담수의 대량 방류 시기와 조사 시기가 일치하는 경우에 민물어류가 하구 해역에서 채집되는 것으로 생각된다. 연도별 정점별 종조성을 이용하여 주성분분석을 실시하였다. 그 결과 종조성은 조사시기별 정점별 차이를 나타내었다.