• Ocean and Polar Research
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• 제43권2호
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• pp.73-88
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• 2021

The community structure and health status of macrobenthos assemblages were investigated in the subtidal area of the Nakdong River estuary, Southern Coast of Korea. Benthic fauna samples were collected seasonally at 8 stations in the subtidal area of the Nakdong River estuary from February 2013 to October 2015. During the survey, a total of 380 species and 4,603 ind./m² of macrobenthos in all sampling areas were collected. The major dominant species were the polychaetes Minuspio japonica, Pseudopolydora kempi, Heteromastus filifomis, Capitella capitata, the amphipod Grandidierella japonica and the bivalvia Arcuatula senhousia. Some species of polychaetes found in the study area consisted of opportunistic species that showed high densities when habitat condition was poor. On the other hand, macrobenthos assemblages in the study area were divided into brackish water and marine groups. Abundance was high in the brackish group, while the number of species and diversity index were high in the oceanic group. The three indices (AMBI, M-AMBI, and BHI) in the assessment of health levels based on the ecological characteristics and number of species in macrobenthic were commonly shown to be in good condition in the group of oceanic stations, while relatively poor conditions were reflected in the group of brackish stations. Compared to other indices, the M-AMBI index of the three indices for health assessment was considered to be a relatively more suitable one to assess benthic ecological conditions.

• Journal of the korean society of oceanography
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• 제33권1-2호
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• pp.18-27
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• 1998

Based on 53 quantitative samples collected in April (23 stations) and August (30 stations) of 1993, the species composition, distribution and abundance of macrobenthic invertebrates and bottom characteristics in Chonsu Bay were conducted. Bottom sediments consisted of mud at the close to the dyke, sandymud in the central bay, and coarse sand in the mouth of the bay. A total of 273 species (177 species in April and 200 species in August) were identified. Mean density per sampling station was 480 ind./m$^2$ in April and 1126 ind./m$^2$ in August, respectively. Number of species and densities decreased in the northern part of the bay. The macrobenthos showed a temporal difference in species composition, range of distribution, and community delimitation caused by larval settling. Although during the settling period in summer, large numbers of juveniles added in most of regions, unrelated to environmental conditions, but, successful recruitment may has been a rare event locally Theora fragilis (bivalve), Lumbrineris longifolia(polychaete), Neptys oligobranchia (polychaete) were numerically dominant, but their densities varied seasonally. Community structures of macrobenthos in Chonsu Bay were affected by several bottom environmental conditions, related to tidal current speed, regionally.

• 환경생물
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• 제36권4호
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• pp.626-637
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• 2018

본 연구는 마산만 하구에 위치한 모래갯벌인 봉암갯벌에 서식하는 대형저서동물의 하계 군집구조 변동양상을 파악하기 위해 2012년부터 2017년까지 하계에 연 2회씩 총 11회에 걸쳐 현장조사가 수행되었다. 봉암갯벌은 모래 함량이 70% 이상인 모래 갯벌로 알려져 있으나, 실제 조사결과 갯벌의 상부지역을 중심으로 니질 함량이 증가하고 있는 것으로 나타났다. TOC 함량도 2000년대 초반에 비해 증가한 것으로 나타났으나, 최대 TOC 함량이 1% 수준으로 심각한 수준의 유기물 증가가 나타나지는 않았다. 봉암갯벌의 대형저서동물 군집구조는 2000년대 초반에 비해 출현종수 및 서식밀도가 크게 증가하였다. 또한 2000년대 초반에 비해 오염지시종의 출현종수 및 서식밀도는 감소하였고, 종다양도지수를 비롯한 군집지수는 크게 증가하는 등 환경 개선의 결과가 일부 나타나고 있다. 마산만의 입구에 위치한 봉암갯벌은 마산만의 영향을 크게 받는다. 마산만 특별관리해역 지정 및 오염 총량제 실시로 인해 오염물질의 농도가 감소하였고, 그로 인해 봉암갯벌로 유입되는 오염물질의 농도 역시 감소되었을 것으로 판단된다. 그러나 환경자료의 부제 및 조사 시기의 차이 등으로 인해 본 연구 결과만으로 환경이 개선되었다고 단정 지을 수 없다. 추후 환경 및 대형저서동물의 개체군, 군집에 대한 추가 조사를 통한 환경개선 유무에 대한 평가가 필요할 것으로 판단된다.

• Fisheries and Aquatic Sciences
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• 제2권2호
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• pp.199-209
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• 1999

Before investigating the long-term variations in macrobenthic communities sampled in the Chokchon macrotidal flat in Inchon, Korea, from 1989 to 1996, we need to understand how environmental factors in the area vary. As potential governing agents of tidal flat communities, abiotic factors such as mean sea level, seawater, air temperature, and precipitation were considered. Data for these factors were collected at equal intervals from 1976 or 1980 to 1996, and were analyzed using a decomposition method. In this analysis, all the above variables showed strong seasonal nature, and yielded a significant trend and cyclical variation. Positive trends were seen in the seawater and air temperatures, and based upon this relationship, it was found that the biological sampling period of our program has been carried out during warmer periods in succession. This paper puts forth some hypotheses concerning the response of tidal flat macrobenthos communities to the changing environment including mild winters in succession.

• 한국관개배수논문집
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• 제17권2호
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• pp.42-48
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• 2010

This study was carried out to investigate the changing of benthic macrobenthos community in Saemangeum subtidal area. The distribution of macrobenthic community is important to assume the benthic environment in study area. Macrobenthic community was investigated three times in 2007 (March, June and September) in the Saemangeum subtidal area. The mean density of macrobenthos was $345{\sim}838ind./m^2$ and the most dominant taxa was benthic polychaete. Opportunistic species such as E.cordatum, T.fragilis, H.filiformis, and Tharyx sp. were shown high appearance rate in study area. The dominance of these opportunistic species suggest that the benthic environment of study area was unstable due to environmental disturbance. But, there are only few point that these species were recorded high densities, and also equilibrium species was dominant, too. It means disturbance and un stability of benthic environment in Seamangeum was not serious yet. so the dynamics and trends of these opportunistic species should be concerned.

• 한국환경생태학회지
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• 제29권2호
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• pp.221-227
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• 2015

This study was carried out to measure seasonal changes in the community structure and species composition of marobenthos in the intertidal area of Dokdo. The macrobenthos identified during this study was comprised of 36 species: predominately 25 species of mollusks(69.4 %), 6 species of arthropods(16.7 %), 3 species of echinodermata(8.3 %) and 1 species of cnidaria (5.6 %). The number of marobenthos species ranged from 27 in Spring to 33 in Autumn. In terms of the top 10 dominant species, there were 7 species of mollusks and 3 species of arthropods in the this study. After analyzing the bray-curtis similarity, it was divided into two large groups(A, B). Such group classification matched the SIMPROF(Similarity Profile Analysis) and the one-way ANOSIM(Analysis of similarities) analysis.

• 한국수산과학회지
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• 제39권spc1호
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• pp.214-222
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• 2006

Dominant species of macrobenthos were analyzed based on differentiation of three distinct methods: the density based method, the biomass based method and LeBris method, by considering the frequency of occurrence using quantitative data collected over 5 years (1993-1998) at 21 stations in Chonsu Bay. Sedimentary environments as well as species composition and diversity showed the spatial and temporal distribution patterns. The ranks of dominant species as determined by the density based method were more similar to the results by the LeBris method than to those from the biomass based method. Considering the temporal variation, LeBris method were more efficient than any other methods for the determination of dominant species in Chonsu Bay. Lumbrineris longifolia, Theora fragilis, and Moerella jedoensis were recognized by all three methods. A one-way analysis of variance indicated spatial distributions patterns among most of the dominant species. These species showed positive correlations to sedimentary parameters such as mean grain size. However, T. fragilis and Paraprinospio pinnata showed the temporal patterns in their distribution, and were also correlated to the benthic environment, organic content and dissolved oxygen. Some dominant species, e.g., T. fragilis, S. scutata, G. gurjanovae proved to be useful benthic indicators based on the environmental variations determinated by long-term benthic ecological monitoring in Chonsu Bay.

• 한국수산과학회지
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• 제36권6호
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• pp.700-707
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• 2003

Surface sediments in the mouth area of Jinhae Bay were investigated to evaluate the benthic environment in terms of geochemical criteria and macrobenthos abundance. Characteristics of the surface sediment distribution exhibited muddy sediments in the most part of study area. Some mixed sediments of coarse sand and mud were distributed along the coastal area of Geoje Island and around the Jeo Islands. Organic matter from ignition loss and total organic carbon from CHNS varied between $8.8-1.7\%,\;and\;4.62-0.77\%,$ respectively. The source of organic matter based on the C/S ratio was mixed with in situ biogenic and terrigenous organic matter. The C/S ratio of organic matter also suggested both an anoxic bottom condition in several parts of the study area. The content of hydrogen sulfide in surface sediment was extremely variable and showed spatio-temporal variation from site to site. In several locations, the content of hydrogen sulfide as an index of eutrophication was over the critical value (0.2 mg/g), suggesting that several parts of the study area were not favorable for the habitat of macrobenthos. The relationship among the number of individuals of marcrobenthos, hydrogen sulfide, and organic matter was not clear, but a potential negative relationship between individuals of marcrobenthos and hydrogen sulfide was indicated.

• 생명과학회지
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• 제22권10호
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• pp.1286-1294
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• 2012

섬진강에서 2009년과 2010년 사이의 대형무척추동물에 대한 생물학적 군락 분석을 실시하였다. 조사 정점에 재해 총 10목 24과 106종이 채집이 되었다. 비록 정점별 종과 개체수는 다르지만 조사 시기별로는 정점 간 유의한 차이를 나타내지 않았다. 정점별 우점종은 달랐다. 2009년 5월 정점에 대해 정점 1이 5종인 반면 정점 2는 66종으로 차이를 보였으며 평균 종수는 38.3종이었다. 반면에 정점 2는 2009년 11월에 가장 많은 종수를 나타내었고 정점 3은 가장 낮았다. 대형무척추동물 중에서 절지동물문(Phylum Arthropod)이 종 수준 또는 개체 수준에서 우점이었는데 종 수준으로 5월은 63.2%, 11월은 60.9%였다. 조사 정점에 대한 환경 인자 분석의 결과 대형무척추 동물의 서식에 미치는 인자로 용존산소량(DO), 생물학적 산소요구량(BOD), 화학적 산소요구량(COD)이 중요한 것으로 나타났다. 생물학적 종다양도는 섬진강 상류에서 하류로 갈수록 낮아지는 경향을 나타내었다.

• Ocean and Polar Research
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• 제24권4호
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• pp.429-442
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• 2002

독도 주변해역의 퇴적물에 살고 있는 대형저서동물에 대한 생물상과 분포양상을 보기 위하여 독도를 중심으로 방사형으로 5개 조사선을 설정하여 수심이 150 m내외의 얕은 곳에서는 반빈그랩으로, 수심이 500 m 이상인 곳에서는 박스코어를 사용하여 1999년 9월과 2000년 5월에 두 차례에 걸쳐 생물채집이 이루어졌다. 독도주변의 대륙붕에서의 퇴적상은 모래로 구성되어 있었으며, 대륙사면역의 퇴적상은 모래가 많이 포함되어 있었고, 울릉분지 내의 퇴적상은 니질이 우세한 퇴적상을 보여 대비가 되었다. 총유기탄소의 함량은 표층에서는 1%전후의 값을 보이고 있으나 정점별 함량 차이가 2배정도 나고 있다 독도 주변 해역의 사면역에 분포하는 대형저서동물을 조사한 결과 8개의 동물문(Phylum)에 속하는 15개 분류군들로 구성되어 있었으며, 조사해역에서 가장 우점한 동물군으로는 다모류로서 전체 출현개체수의 80.6%를 차지하였고, 연체동물(6.2%), 갑각류(4.0%), 성구동물(3.9%), 원생동물문의 유공충류(2.8%), 유형동물(1.4%) 순으로 우점하였다. 대륙사면의 우점종은 짧은더듬이달걀발갯지렁이(Exogone veugera)(40.9%), Cossura longicirrata(8.4%), Tharyx sp.(6.6%), Scalibregma inflatum(4.9%), Aglaophamus malmgreni(4.7%), Aricidea ramosa(3.8%), Sigambra tentaculata(3.7%) 등이었다. 대륙붕에서의 우점종은 Chone sp.가 전체 개체수의 49.3%를 차지하여 가장 우점하는 종이었고, Tharyx sp.(18.4%), Ophelina acuminata(6.7%), Chaetozone setosa(3.8%), Myriochele sp.(3.3%), Glycera sp.(2.6%), Aedicira sp.(2.4%) 등이었다. 다모류군집의 섭식 유형은 심해의 사면역에서는 표층퇴적물식자가 전체 다모류 개체수의 54.7%를 차지하여 가장 많은 비중을 차지하였고, 천해의 붕단역에서는 여과식자가 전체의 49.7%를 차지하여 가장 우점한 섭식유형이었다. 서식밀도는 울릉분지의 정점 A19에서 5종류의 저서생물과 152개체/m^2$로 가장 낮은 서식밀도와 빈약한 종조성을 보였고, 사면역의 정점에서는 평균 서식밀도가 3100개체/m^2$였다. 대륙붕에서는 평균 456개체/m^2$의 서식밀도를 보였다. 다모류의 출현종 유사도에 의한 집괴분석과 배열법의 결과 독도를 중심으로 남북에 위치한 정점들은 종조성에 차이를 보였다. 퇴적물 깊이 따른 저서동물의 수직분포 양상은 표층에서 가장 많은 개체수가 분포하며 깊이가 증가할수록 감소하는 양상을 보였다.