• Journal of the Korean earth science society
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• v.29 no.1
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• pp.13-28
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• 2008

About 450 specimens of Lockeia were discovered from the lacustrine siltstone of the Early Cretaceous Jinju Formation of Jin Island, southern coast of Korea. They are very elongated, seed-shaped Lockeia characterized by a large size, mostly 60-70 mm long and 15-20 mm wide. They are characteristically sharp longitudinal furrow bounded by steeply inclined both margins, elevated marginal rims and sharp pointed both longitudinal furrow ends. This trace fossil is herein described as Lockeia gigantus ichnosp. nov. Plicatounio, a freshwater bivalve which does not occur occurs occasionally within Lockeia gigantus is regarded as the most-likely producer of this resting trace fossil. This new trace fossil represents the largest Lockeia ever known and the first record of Lockeia from the Cretaceous non-marine deposits in the world. This fossil also represents an unusual example of resting trace fossil (Lockeia) associated with a possible producer (bivalve Plicatounio) lived in community in the shallow lacustrine environment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.894-901
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• 2010

To measure the heavy metal contents of marine invertebrates, we collected 239 individuals representing 52 species from the eastern (Pohang), western (Gunsan), and southern (Tongyeong) coasts of Korea: 34 species of molluscan shellfish (Gastropoda and Bivalvia), 6 species of Cephalopoda, 8 species of Crustacea, and 4 other species. The mean levels of the heavy metals in the samples taken from the edible portion of each Gastropoda were high in the order of Zn ($21.471\;{\mu}g/g$), Cu ($4.115\;{\mu}g/g$), Mn ($0.868\;{\mu}g/g$), Ni ($0.254\;{\mu}g/g$), Pb ($0.238\;{\mu}g/g$), Cd ($0.154\;{\mu}g/g$), and Cr ($0.110\;{\mu}g/g$). The heavy metals in the Bivalvia were high in the order of Zn ($35.655\;{\mu}g/g$), Mn ($5.500\;{\mu}g/g$), Cu ($3.129\;{\mu}g/g$), Cd ($0.423\;{\mu}g/g$), Ni ($0.402\;{\mu}g/g$), Cr ($0.233\;{\mu}g/g$), and Pb ($0.232\;{\mu}g/g$). The heavy metals in the Cephalopoda were high in the order of Zn ($18.380\;{\mu}g/g$), Cu ($3.594\;{\mu}g/g$), Mn ($0.630\;{\mu}g/g$), Cr ($0.150\;{\mu}g/g$), Pb ($0.068\;{\mu}g/g$), Cd ($0.034\;{\mu}g/g$), and Ni ($0.030\;{\mu}g/g$). The heavy metals in the Crustacea were high in the order of Zn ($25.333\;{\mu}g$/g), Cu ($9.042\;{\mu}g/g$), Mn ($0.659\;{\mu}g/g$), Cr ($0.592\;{\mu}g/g$), Cd ($0.207\;{\mu}g/g$), Pb ($0.126\;{\mu}g/g$), and Ni ($0.094\;{\mu}g/g$). Therefore, the mean levels of the harmful heavy metals (Cd and Pb) in marine invertebrates were high in the order of Bivalvia>Crustacea＝Gastropoda>Cephalopoda. The average daily intakes of the heavy metals from the fisheries products were as follows: Cd ($6.88\;{\mu}g$), Cr ($19.13\;{\mu}g$), Cu ($137.02\;{\mu}g$), Mn ($156.13\;{\mu}g$), Ni ($11.39\;{\mu}g$), Pb ($7.01\;{\mu}g$) and Zn ($1,025.94\;{\mu}g$). The average weekly intakes of Cd, Cu, Pb and Zn from the fisheries products were 11.47%, 0.46%, 3.27% and 1.71% respectively, as compared with PTWI (Provisional Tolerable Weekly Intakes) established by FAO/WHO Expert Committee for Food Safety Evaluation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.1
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• pp.14-28
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• 2003

The macrobenthic faunal community of Gwangyang Bay comprised 154 species and showed the overall mean density of 1,286 individuals/$m^2$. Polychaetes were the most important component of the macrofaunal community in species richness, abundance and biomass. The dominant species in abundance were poly-chaetes like Tharyx sp.(44.8%), Lumbrineris longifolia(14.0%), Heteromastus filiformis(3.6%), a mussel Mytilus edulis, and an amphipod crustacean Corophium sinense. The abundance and biomass in the western part of the bay were lower than in the channel regions and mouth of the bay. The community indices showed the same trend in the spatial distribution with the abundance and species richness. The study area can be divided into seven station groups； five station groups in the eastern part, two groups in the channel and open mouth part of the bay.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.15-24
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• 2002

Polychloinated biphenyls (PCBs) 및 유기염소계 농약은 UNEP에서 지속성유기오염물질(POPs)로 규정하고 있는 화합물로서 환경내 잔류성이 강하고 먹이사슬을 딸라 생물증폭되는 화합물로 알려지고 있다. 광양만의 유기염소계화합물의 오염현황을 파악하고자, 표층퇴적물, 생물, 해수 중의 농도를 정량ㆍ정성분석하였다. 해수의 용존상을 제외한 모든 매질에서 PCBs와 DDT 화합물이 주요 유기염소계 화합물로 검출되었다. 퇴적물 중의 총 PCBs, DDTs, CHLs(클로르단 화합물), HCHs (헥사클로르사이클로헥산)의 농도는 각 각 0.61-1.97 ng/g, 0.16-1.16 ng/g, nd-0.51 ng/g, 0.05-0.79 ng/g의 농도 범위를 나타냈다. 퇴적물 중의 유기염소계화합물의 농도수준은 우리나라 주요 만 (부산만, 영일만, 울산만, 경기만)에서 조사된 퇴적물 중의 농도와 비교할 때 낮은 수준이며, 저서생물에 독성학적 위해를 일으킬 수 있는 수준에 미치지 못한다. 이매패류 중의 유기염소계화합물의 농도는 총 PCBs (4.42-19.ng/g), 총 BBTs (7.54-22.6ng/g), CHLs (0.49-2.0ng/g), HCHs (0.82-7.32ng/g)의 범위를 나타었다. PCBs의 경우 산업시설 및 도시 주변에서 상대적으로 높았으나 전반적으로 비슷한 수준을 나타냈다. 해수 중의 PCBs 농도는 제철소 인근에서 상대적으로 높았으며, 해수의 용존상에서는 입자상에서와 달리 DDTs보다 HCHs가 상대적으로 높은 농도로 검출되었다. 이는 두 상에 분배되는 이들 화합물의 성향에 따르는 것으로 파악된다.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.216-222
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• 2006

Feeding habits of Pagrus major collected in the coastal waters off Busan from January to December 2004 were studied. P. major ranged form 8.5 to 44.6 cm in standard length. P. major was a carnivore which consumed mainly hermit crabs, amphipods, crabs, shrimps, polychaetes, echinoderms, and fishes. Its diets included small quantities of gastropods, bivalves, stomatopods, cephalopods, cnidarians, and isopods. It showed ontogenetic changes in feeding habits. Small individuals (8~15 cm SL) preyed mainly on shrimps. However, individuals from 15 cm to 25 cm SL preyed mainly on hermit crabs and polychaetes. Individuals over 25 cm SL preyed mainly on fishes and echinoderms.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.257-264
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• 2021

In this study, we analyzed the food components in the release product that sampled Sinonovacula constricta from the foreshore littoral at Byeongnyang-myeon, Suncheon Bay. We used microscopy and next-generation sequencing (NGS) to evaluate the applicability of morphological and molecular methods to analyze release products. The higher species diversity observed in the NGS method is due to the different levels of species identification, as microscopy displays morphological and anatomical levels of plankton species identification in S. constrita. Moreover, NGS can identify the level of species in the organic matter by using the 18s_V9 primer.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.512-518
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• 1997

This study was performed to determine the amount of aluminum, which is one of the factors of Alzheimer's disease, In some fishes caught from some areas of the west coast in Korea. The 46 aquatic products were composed of fishes, molluscs, and salt-fermented products (jeot-gal). The 24 fishes were Hickory shad, Gobies, Pomfref, Atkafish, Flounder, Jambeng-ie Monk fish, Yellow hair tail, Mackerel, Bartailed flathead, Alaska pollack, Brown croaker, Eel, Fine-spotted flounder, Black spotted grouper, Sea-eel, Pacific saury, Areliscus honaleus, Small boil-dried anchovy, Croaker, Hair tail, Sea bream genuine, Motleystrip rainbowfish, and Bastard halibut. The 15 Molluscs were Whip-arm octopus, Sea arrow, Common squid, Han chi, Cuttle fish, Turban shell, Pond snail, Orient calm, Surf calm, Butter calm, Crib shell, Oyster, Egg cockle, Little neck calm, and Arkshell. The 7 salt-fermented products were salt-fermented Shrimp, Little neck, Oyster, Shad, Gonjeng-ie, Hqangsegi, and Squid. All of them were ashed with 5$m\ell$ HNO$_3$ and then with 10$m\ell$ ternary solution (HNO$_3$ : H$_2$SO$_4$ : HClO$_4$= 10 : 1 : 4). After ashing of the samples, the aluminum amount were measured by ICP. The aluminum amount of molluscs was significantly higher than that of fishes and salt-fermented products(p＜0.01). The aluminum amount of Orient calm and Healak in molluscs were 827.70, 812.55ppm, respectively, which were the most amounts compared nth that of the other samples. But the aluminum amounts of Bartailed flathead and Sea bream, genuine In fishes were 0.98, 0.97ppm, respectively, which were the least amounts compared with that of other samples. This study was limited within 46 aquatic samples, therefore I hope there will be wider efforts to determine about auminum amount in broade range of aquatic foods for the prevention of Alzheimer's disease.

• Korean Journal of Ecology and Environment
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• v.43 no.3
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• pp.369-376
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• 2010

A novel or canal-type continuous removal of organic matter (C-CROM) with combined freshwater bivalves (Unio douglasiae and Anodonta woodiana) was developed to improve the water quality (IWQ) of eutrophic reservoirs. The first experiment was performed for 12 days to measure the IWQ using 256 individuals of combined bivalves (ca. 7:3), at the same density that distributed in the collection stream. The second experiment was conducted to evaluate the efficacy of IWQ with the addition of each 30% of two mussels for 14 days. Results indicated that a novel C-CROM significantly decreased suspended solids, chlorophyll-$\alpha$, transparency, total nitrogen and phosphorus, and increased ammonium and biodeposition (t-test, P<0.001 for all), while other dissolved inorganic nutrients such as $NO_2$, $NO_3$, and SRP did not change (t-test, P>0.5). Daily IWQ performances of C-CROM with combined mussels was about two times higher to the previous studies using single species where less suspended inorganic nutrients were released except for ammonia. Collectively, a C-CROM is more strategic to the water quality improvement of eutrophic lake.

• The Korean Journal of Malacology
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• v.15 no.1
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• pp.57-62
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• 1999

Condition indices (Cl) are considered to be useful measurements of the nutritive and health status of bivalves although studies on Cl of bivalves are limited due to the lack of a standard formula for calculating Cl. This study attempts to generate Cl of the mussel, Mytilus coruscus inhabiting along the coastal area of Chuja Island in Cheju using three primary formulas. the formulas used in this study: (1) Cl-vol= [tissue dry weight (g) 1000] /shell cavity volume (ml). (2) Cl-wt= [tissue dry weight (g) 1000] / internal shell cavity capacity (g). (3) Cl-size= tissue wet weight (g)/[shell length (mm)]$\^$3/. Monthly condition indices calculated with the three formulas are compared using ANOVA, Duncan's multiple range test and Pearson correlation coefficient. In Chuja Island M. coruscus collected ranged from 50 to 180 mm in shell length. Monthly ranges of Cl-values were 67.48 to 140.61 (Cl-vol), 74.67 to 118.02 (Cl-wt) and 1.4 10$\^$-5) to 1.6 10$\^$-5/ (Cl-size). Cl-vol values in August were higher than two Cl-values in the other months. Monthly Cl-vol was significantly different from Cl-wt and Cl-size. (p<0.05). The results of this study suggest that volumetric condition index (Cl-vol) used in this study is acceptable as a standard measure to evaluate conditions of M. coruscus.

• The Korean Journal of Malacology
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• v.31 no.1
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• pp.9-19
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• 2015

Germ cell development and cyclic changes in the epithelial cells of the seminal vesicle of the male rapa whelk, Rapana venosa, were investigated by cytological and histological observations. The process of germ cell development can be classified into five stages: (1) spermatogonial, (2) primary spermatocyte, (3) secodary spermatocyte, (4) spermatid, and (5) spermatozoon. In particular, four atypical cells (Type IA, IB, IIA and IIB cells) occur among normal germ cells in the acini during spermatogenesis. Presumably, the atypical cells, which have lysosome-like vacuoles or lysosome-like bodies in the cells, are involved in breakdown and absorption themselves in the acini. However, atypical cells were not found in the epithelial cells of the inner layer of the seminal vesicle. A considerable amount of spermatozoa are transported from the testis towards the the seminal vesicles until late July. The main coupulation period is between June and July. The process of the cyclical changes of the seminal vesicles can be classified into three phases: (1) resting, (2) accumulating, and (3) spent. Yellow granular bodies are involved in resorption or digestion of residual spermatozoa.