• 생태와환경
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• 제38권2호통권112호
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• pp.188-195
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• 2005

2000년부터 2004년까지 5년간 횡성호 일대의 어류군집 동태를 조사한 결과는 다음과 같다. 조사기간동안 출현한 어류는 총 10과 39종이었으며 이 중 한국고유종은 Rhodeus pseudosericeus 등을 포함하여 총 17종 (43.59%) 이었다. 우점종은 Acheilognathus lanceolatus (20.10%), Zacco platypus (15.94%), Z. temmincki (6.92%), Carassius cuvieri (6.33%), A. rhombeus (6.18%), Pungtungia herzi (5.13%), Pseudorasbora parva (4.93) 등이었다. 조사시기별 출현종을 근거로 생활형에 따른 어류군집은 담수가 되면서 점차 저서성 어종의 수가 감소하였고 부유성 어종이 증가하는 것으로 나타났다. 또한 조사시기별 유사도 분석을 한 결과 각 조사시기는 비가중치 평균연결법 (UPGMA)에 의해 3개의 그룹으로 나누어졌다. 한편 다른 인공호와 본 조사의 어류상을 근거로 유사도 분석을　한 결과 수계에 따라 2개의 그룹으로 나누어졌으며 같은 수계 내에서 다시 3개의 그룹으로 나누어졌다. 이 중 횡성호 어류군집의 현재 상태는 북한강 중류의 춘천-청평호와 유사한 것으로 나타났다.

• 한국어류학회지
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• 제9권1호
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• pp.79-90
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• 1997

1995년 6월부터 1996년 5월 사이 대천 해빈 쇄파대에서 월별로 어류를 채집하여, 종조성, 양적 변동 및 군집구조를 분석하고, 1984~85년의 종조성 자료와 비교하여 두 조사시기 사이의 종조성 변화에 대하여 고찰하였다. 재료는 매월 그믐 사리 저조 때 지인망을 5회 예인하여 수집하였다. 본 조사에서는 총 26종의 어류가 출현하였으며, 날개망둑(Favonigobius gymnauchen), 주둥치(Leiognathus nuchalis), 청보리멸(Sillago japonica), 돌가자미(Kareius bicoloratus)가 우점하였다. 봄에는 주거종인 날개망둑의 성어가 우점하였고, 6월부터 내만성 부어류와 저어류의 유어들이 대량 출현하여 여름동안 높은 생물량을 보였으며, 11월 이후 수온이 낮아지며 소수종 만이 출현하였다. 1984~85년 같은 해역에서 수집된 자료와 비교하면, 계절에 따른 종조성 변화 양상은 유사하였으나 군집구조는 차이를 보였다. 돌가자미, 돛양태(Repomucenus lunatus), 흰베도라치(Enedrias fangi), 참서대(Johnius beiengerii), 두줄망둑(Tridentiger trgonocephaalus), 주둥치와 민태(Johnius belengerii)는 1984~85년에 비하여 1995~96년에 수적으로 증가하였고, 곤어리(Thrissa koreana), 밴댕이 (Sardinella zunasi), 학꽁치(Hyporhampus sajori), 숭어(Mugil cephalus), 얼룩망둑 (Chanogobius mororana), 전어(Konosirus punctatus), 줄공치(Hyporhampus intermedius) 및 은어(Plecogtosus altivelis)는 1984~85년에 비하여 1995~90년에 감소하였다. 숫적으로 증가한 종 중 주둥치를 제외하면 저어류들이었고, 감소한 종은 얼룩망둑을 제외하면 부어류들이었다. 이 결과는 천수만 방조제 건설 이후 해수 유동이 약하여지며 세립퇴적물이 증가하여, 세립퇴적물을 선호하는 어류가 증가하였고, 쇄파대에는 탁도가 증가하여 일부 여과식자에게 부적합한 환경이 조성되어 부어류들이 감소한 것으로 추정된다.

• 한국환경과학회지
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• 제33권7호
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• pp.489-500
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• 2024

The newly created wetlands in the Geum River Basin have undergone various environmental changes since their establishment in 2012. In this study, we evaluated the influence of environmental characteristics on zooplankton, which are sensitive to environmental changes, and considered appropriate wetland management plans. The thirty-two wetlands were divided into two groups based on the differences in their macrophyte cover. High species diversity and zooplankton density were found in cluster 2, which had abundant macrophyte cover. In contrast, cluster 1, with low plant cover, had lower species diversity and zooplankton density, primarily of pelagic zooplankton. To maintain species diversity and abundance of zooplankton in wetlands, we recommend implementing a management strategy that encourages the development of various plant communities through efficient water conveyance functions.

• 비교문화연구
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• 제29권
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• pp.177-199
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• 2012

Nowadays migrations between the countries are getting each day more active and a mixture of people with different cultural backgrounds strengthens the hybridism, whereupon the point of view on the migration of Koreans has been changed from a diasporan perspective to an transnational one. The expansion of the transnationalism affects the identity of the subsequent generations of the immigration giving way to a psychologically deterritorialized social identity, which is an important consideration in the study of subsequent generations of the immigration. This study examined the Korean immigration history and the current status of the Korean community in Spain since the 1960s. The early immigrants like fishing vessel crew members, instructors of Taekwondo, chicken sexers who, despite the limits of foreigners in Spain, went to find out the source of life with no hesitation, overcame the difficulties of the early settlers and finally managed to achieve local success. Current history of immigration that began in the mid-1960s went through the maturity during the 1970s and 80s and the Koreans in Spain these days, who have undergone differentiation in the occupational structure because of the crisis of pelagic fisheries, face new challenges due to changes in the environment of the country they reside. The Korean community is regarded as an 'exemplary minority group (Model Minority)' even though it is a minority group in number. Now that the interest for overseas Koreans is higher than ever at home and abroad, due to the economic growth of the Republic of Korea, the spread of its cultural influence -the Korean Wave as proof-, and the overseas Koreans suffrage conducted, the research of the Korean residents in Spain will be important as an advanced research of an unexplored field, as well as an opportunity to broaden the horizons of the existing study area that has mainly dealt with major regions only.

• Ocean and Polar Research
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• 제33권4호
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• pp.457-472
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• 2011

To elucidate the trophic role of heterotrophic nano- and microplankton (HNMP), we investigated their biomass, community structure, and herbivory in three different water masses, namely, south of Polar Front (SPF), Polar Front Zone (PFZ), the Sub-Antarcitc Front (SAF) in the Drake Passage in the Southern Ocean, during the austral summer in 2002. We observed a spatial difference in the relative importance of the dominant HNMP community in these water masses. Ciliates accounted for 34.7% of the total biomass on an average in the SPF where the concentration of chlorophyll-a was low with the dominance of pico- and nanophytoplankton. Moreover, the importance of ciliates declined from the SPF to the SAF. In contrast, heterotrophic dinoflagellates (HDFs) were the most dominant grazers in the PFZ where the concentration of chlorophyll-a was high with the dominance of net phytoplankton. HNMP biomass ranged from 321.9 to 751.4 $mgCm^{-2}$ and was highest in the PFZ and lowest in the SPF. This result implies that the spatial dynamic of HNMP biomass and community was significantly influenced by the composition and concentration of phytoplankton as a food source. On an average, 75.6%, 94.5%, and 78.9% of the phytoplankton production were consumed by HNMP in the SPF, PFZ, and SAF, respectively. The proportion of phytoplankton grazed by HNMP was largely determined by the composition and biomass of HNMP, as well as the composition of phytoplankton. However, the herbivory of HNMP was one of the most important loss processes affecting the biomass and composition of phytoplankton particularly in the PFZ. Our results suggest that the bulk of the photosynthetically fixed carbon was likely reprocessed by HNMP rather than contributing to the vertical flux in Drake Passage during the austral summer in 2002.

• 생태와환경
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• 제37권4호통권109호
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• pp.368-372
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• 2004

1980년대 이래로 Biwa호 북측 지역 연안대에서 초여름 동안 Spjrozyra에 의해 조성된 저서 사상성 부착녹조류 군집의 발달이 관찰되어 왔다. 이들의 발달은 초여름 저서 조류 군집의 생물량 증가와 생물량의 계적적 변동 양상에 영향을 미친 것으로 판단된다. 본 논문에서는 Spjrozyra 군집 발달의 원인을 1963-64년, 1995-96년, 2001-02년 동안 수행된 연구 결과(특히,영양염,$NO_3^--N$)에기초하여 고찰하였다. 6월 동안의 $NO_3^--N$의 농도는 1964년 6월에 $20{\mu}g\;L^{-1}$에 비교할 때 1995년과 2002년은 $100{\mu}g\;L^{-1}$ 이상이었다. 이 결과는 $NO_3^--N$가 1963년도에 Spjrogyra 성장에 대해 제한요인으로 작용하였음을 시사한다. Biwa호 북측 지역 개방수역에서 $NO_3^--N$의 농도는 1950년대이후 유역에서의 인구증가와 경제성장의 영향으로 뚜렷하게 증가하였다. 따라서 Biwa호에서 Spjrogyra 군집의 발달은 인간활동에 의한 영양염 공급의 증가의 결과로 추정된다.

• Ocean Science Journal
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• 제42권3호
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• pp.179-192
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• 2007

Understanding in climate effects on marine ecosystem is essential to utilize, predict, and conserve marine living resources in the 21st century. In this review paper, we summarized the past history and current status of Korean fisheries as well as the changes in climate and oceanographic phenomena since the 1960s. Ocean ecosystems in Korean waters can be divided into three, based on the marine commercial fish catches; the demersal ecosystem in the Yellow Sea and the East China Sea, the pelagic ecosystem in the Tsushima Warm Current from the East China Sea to the East/Japan Sea, and the demersal ecosystem in the northern part of the East/Japan Sea. Through the interdisciplinary retrospective analysis using available fisheries, oceanographic, and meteorological information in three important fish communities, the trend patterns in major commercial catches and the relationship between climate/environmental variability and responses of fish populations were identified. Much evidence revealed that marine ecosystems, including the fish community in Korean waters, has been seriously affected by oceanographic changes, and each species has responded differently. In general, species diversity is lessening, and mean trophic level of each ecosystem has decreased during the last $3\sim4$ decades. Future changes in fisheries due to global warming are also considered for major fisheries and aquaculture in Korean waters.

• 한국수산과학회지
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• 제22권1호
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• pp.1-8
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• 1989

Demersal fish community in Cheonsu Bay was analyzed using fish samples collected by a small otter trawl from March to November, 1986. Of the 32 species identified, Nibea argentatus, Chaturichthys stigmatias Crptocentrus filifer, Cynoglossus joyneri and Jonius belengeri pre-dominated in abundance. Based upon principal component analysis of species composition data, the fishes were grouped into resident, migrant and temporal species. Resident fish wintered in the deeper part of the bay, showing a peak in biomass during cold months. In spring, warm weather seasonals, adult N. argentatus and J. belengeri, migrated o the bay for spawing. However, the biomass of the migrant was not more than that of the wintered adult residents. From July to September, juveniles of many species were collected, but the number of individuals was smaller than that of the littoral or pelagic zones. This suggests that the deeper area of the bay did not serve as a main nursery ground of the juveniles with the exception of two migrant scianid fishes. As a result, the benthic fish of the bay were more abundant in cold months than in summer.

• Ocean and Polar Research
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• 제25권2호
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• pp.213-226
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• 2003

Kongsfjorden near Korean Arctic Station, Dasan, is a glacial fjord in the Svalbard archipelago, Arctic that is influenced by both Atlantic and Arctic water masses. During the Arctic field season August 2002, surface temperature, salinity, density, and phytoplankton biomass (chi a) was measured in Kongsfjorden. A total of 15 surface samples were collected for the phytoplankton related measurements. Chl a values ranged from 0.08 to 1.4mg chi a $m^{-3}$ (mean of 0.53mg chl a $m^{-3}$) in the overall surface stations. The highest values of the chi a concentrations (> 1.0mg chi a $m^{-3}$) were found near glacier in the northeastern part of Kongsfjorden. Nanoplanktonic (< $20{\mu}m$) phytoflagellates were important contributors for the increase of the chi a. The nano-sized phytoflagellates accounted for more than 90% of the total chi a biomass in the study area. Surface temperatures and salinities ranged from 2.5 to $7.18^{\circ}C$ (mean of $4.65^{\circ}C$) and from 22.55 to 32.97 psu (mean of 30.16 psu), respectively. The physical factors were not highly correlated with phytoplankton distribution. The character of surface water due to down-fjord wind was highly similar to phytoplankton distribution. Drifting ice, freshwater, and semdiment inputs from large tidal glaciers located in the inner part of Konsfjorden create steep physico- and biogeochemical environmental gradients along the length of this ford. The glacial inputs cause reduced biodiversity biomass and productivity in the pelagic community in the inner fjord. Primary production of benthic and pelagic microalgae is reduced due to the limited light levels in the turbid and mixed inner waters. The magnitude of glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground fer marine mammals and seabirds. Especially, seabirds play the largest energy intake and also export nutrients for primary production of the marine microalgae. Kongsfjorden has received a lot of research attention as a site for exploring the impacts of climate changes. Dasan Station in Kongsfjorden will be an important Arctic site for monitoring and detecting future environmental changes.

• 한국해양학회지
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• 제19권2호
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• pp.217-227
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• 1984

1981年에서 1982年 사이 淺水灣 入口에서 小型定置網으로 蒐集한 魚類 群集 의 種組成과 量的 變動을 季節別로 分析하였다. 總 64種의 魚類가 採集되었으며, 小數種이 魚類群集을 優占하였다. 이른 봄에는 漁獲量이 적었으며, 베로라치 (Enedias fangi)와 까나리(Ammodytes personatus)가 優占하였다. 魚類의 種數, 個體數 및 漁獲量은 늦봄에 年中最大값을 보였으며, 이는 魚類들이 産卵 혹은 攝餌를 위하여 灣으로 回族하여 들어오기 때문인 것으로 보인다. 이 시기에는 3種 의 乳泳生魚類, 밴댕이 (Harengula zunasi), 멸치(Engraulis japonica) 및 전어 (Konosirus punctatus)가 優占하였으며, 種類, 個體數 및 어획량이 낮에 비하여 밤에 훨씬 많았다. 여름에는 種數 및 漁獲量이 크게 감소하였으며, 이는 産卵후 成漁가 죽거나, 널리 퍼져 있기 때문인 것으로 보인다. 가을에는 그 해에 태어난 魚類가 再介入하여 어획량이 증가하였다. 이 시기에는 봄, 여름에 産卵한 밴댕이, 멸치 및 전어의 幼漁가 우점하였다. 또, 낮과 밤의 種組成도 큰 차를 보이지 않았다.