• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.6
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• pp.408-414
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• 1990

Phytoplankton dominant species and the relationship between nutrient concentrations and salinity in the Yeosu Haeman were investigated in April, June and August, 1989. The dominant species in the Yeosu Haeman were similar with those reported previously in the inner Kwangyang Bay except a diatom, Navicula sp. in April. The species seems to be advected to the surface from the bottom during the dredging operation. Nitrate concentrations were negatively correlated with salinity during the study period, while silicate and phosphate concentrations had no relationships with salinity except in April. It seems that biological uptake of nitrate was not significant, but concentrations of silicate and phosphate were affected by the phytoplankton uptake in the Yeosu Haeman.

• Journal of environmental and Sanitary engineering
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• v.19 no.2
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• pp.37-44
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• 2004

Flora and standing crops of the periphyton communities were examined at five sites in the mountainous streams of the Dam of Peace, Korea, from June to November 2003. The attached algal communities comprised totally 76 taxa belong to the 5 classes. In species composition, diatoms and green algae overwhelmingly dominated the periphyton communities although their standing crops were low. During the survey period, major dominant species were Navicula gregaria and Nav. pupla var. capitata, as 11.7% and 8.9% of total standing crop, respectively. Other subdominant species were Scenedesmus ecornis and Spirogyra weberii in green algae, Cymbella affinis, Cymbella minuta. Fragilaria capucina, Melosira varians, Naw. cryptocephala, Nav. exigua var. capitata, Nav. gregaria, Nit. sublineuris in diatom. In the seasonal appearances, S. ecornis and Oscillatoria nigra were occurred in summer, C. affinis and F. capucina in autumn, and N. sublinearis, and species Spirogyra weberii in winter, respectively.

• ALGAE
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• v.21 no.4
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• pp.377-392
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• 2006

Seventy eight taxa of Bacillariophyceae belonging to 1 species of Aulacoseira, 1 species of Cyclotella, 1 species of Tabellaria, 1species of Diatoma, 1 species of Thallasionema, 1 species of Grammatophora, 1 species of Fragilaria, 8 species of Synedra, 2 species of Achnanthes, 1 species of Cocconeis, 1 species of Diadesmis, 1 species of Diplonies, 2 species of Gyrosigma, 3 species of Pleurosigma, 15 species of Navicula, 4 species of Pinnularia, 3 species of Stauroneis, 1 species of Eunotia, 2 species of Himantidium, 11 species Gomphonema, 5 species of Cymbella, 1 species of Cocconema, 4 species of Amphora, 1 species of Rhopalodia, 5 species of Nitzschia and 1 species of Surirella were reported from different fresh water habitats of Orissa state and its neighbouring regions of India. All the taxa were recorded for the first time from this region.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.522-523
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• 2000

우리나라에서 건강식품으로 널리 알려져 있는 참전복은 불로장수의 식품으로 널리 애용되고 있을 뿐만 아니라 발암억제 물질인 paolin을 함유하고 있어, 세계적으로 상품가치가 인정되고 있다. 이러한 중요성에도 불구하고 참전복 부착치패의 성장 및 생존율 제고는 아직까지도 해결되어야 할 문제로 남아 있는 실정이다. 참전복 부착치패의 먹이선택성 및 유인성에 관한 기존의 연구를 보면 Viana et al. (1994)은 평균 각장 4.2 cm인 치패를 이용하여 배합사료의 9가지 원료에 대한 유연성을, Harada and Kawasaki (1982)는 각장 2.4 cm 이상인 치패를 대상으로 해조류 3종(미역, 톳, 파래)의 유인효과에 관하여 보고하였다. 그러나 이와 같은 보고들은 전복 종묘생산 현장에서 보다 빠른 시기에 박리하여 해조로 먹이 전환을 하기 위한 노력과는 어느 정도의 거리가 있다고 판단된다. 따라서 본 연구에 있어서는 평균 각장 5.0$\pm$1.0 mm인 치패를 박리하여 Navicula spp., 해조 2종(다시마, 파래) 및 자체 제조한 사료를 공급하여 먹이별 유인효과를 관찰하였다. (중략)

• Fisheries and Aquatic Sciences
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• v.25 no.1
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• pp.20-30
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• 2022

The present study was carried out to investigate the food and feeding habits of Oreochromis niloticus in Lake Shala to manage this species in this high Soda Lake. Stomachs of 226 fish (65.9%) had different food items, while those of 117 fish (34.1%) were empty. Phytoplankton was the dominant food categories occurring in 90.3% of the stomachs estimated and contributed 75.5% of the total volume. Bacillariophyceae (Nitzschia, Anomoeoneis, Navicula and Melosira) were identified as the most desired phytoplankton item. The prey items of O. niloticus differed among size classes (ANOVA, p < 0.05). The main prey items were zooplankton by the smaller-size class, and phytoplankton in fish of the larger-size class. Seasonal variation in the diet composition was evident (t-test, p < 0.05) and zooplankton, chironomids, nematodes, fish scales and detritus were important during the wet season, while phytoplankton predominates during the dry season. This study concludes that O. niloticus had a phytoplanktivores feeding mainly on phytoplankton and their feeding habits influenced by season and fish size in Lake Shala.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.239-251
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• 2011

To compare the different water environments in the Jigsaw stream (st. 1, 2) and Jujin stream (st. 3, 4) crossing over the Byeonsan-Bando and Seonunsan parklands, the physico-chemical factors and the species compositions of epilithic diatoms were analyzed from March 2009 to February 2010. The mean values of conductivity (681.1 ${\mu}S\;cm^{-1}$), suspended solids (27.83 mg $L^{-1}$), biological oxygen demand (3.15 mg $L^{-1}$), total nitrogen (3.24 mg $L^{-1}$), total phosphorus (0.24 mg $L^{-1}$) and chlorophyll-${\alpha}$ (12.99 mg $m^{-3}$ ) in Jujin stream were significantly higher than each element in Jigsaw stream. Eighty taxa were classified into 73 species and seven varieties belonging to 24 genera, eight families, three suborders and two orders in Jigsaw stream. Eighty eight taxa were classified into 81 species and seven varieties belonging to 22 genera, seven families, three suborders and two orders in Jujin stream. Biological water quality assessments revealed that Jigsaw stream was ${\beta}$~${\alpha}$-oligosaprobic and Jujin stream was ${\beta}$-mesosaprobic. Dominant and diversity indices were indicated from 0.25~0.81 and from 1.73~4.14 in Jigsaw stream, respectively, and from 0.29~0.64 and from 2.72~4.02 in Jujin stream, respectively. Jujin stream was more eutrophic than those of Jigsaw stream. The different water environments between the two streams could be due to the different ecosystems of the neighboring basins of each stream crossing over in the mountain. Further studies should investigate the water environments of two streams by continuous and regular monitoring to analyze the different ecosystem mechanisms.

• Journal of Aquaculture
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• v.8 no.4
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• pp.355-366
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• 1995

In order to identify some suitable diatoms as a live food source, effects of seven diatom species (Chaetoceros simplex, Navicula incerta, Phaeodactylum tricornutum, Nitzschia closterium, Skeletonema costatum, Thalassiosira pseudonana, Thalassiosira weissflogii) were examined on specific growth rate, mean celt volume, chemical composition and general fatty acid composition. In cell volume. T. pseudonana was the smallest $(125{\mu}m^3)$ and T. weissflogii the largest $(824{\mu}m^3)$. However the specific growth rate of the largest diatom was the lowest (0.5016/day), and that of S. costatum was the highest (0.9928/day). The crude protein content of seven diatom species varied from $18.96\%$ (T. pseudonana) to $24,4\%$ (T, weissflogii). The crude lipid content of C. simplex was the highest $(8.43\%)$, and that of T. pseudonana was the lowest $(3.13\%)$. The total content of polyunsaturate fatty acids which are important for bivalve larvae was higher in C. simplex than those in other species. The total percent of polyunsaturate fatty acids from N. incerta and T. weissflogii was relatively lower than that from other species. Dietary value of seven diatom species were finally examined with Pacific oyster larvae Crassostrea gigas. In this experiment, C. simplex showed the highest survival rate and growth, and the larvae feed on S. costatum and T. weissflogii showed the poorest results. This results C. simplex could be more useful live food for bivalve larvae than other diatom species tested.

• Journal of Conservation Science
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• v.27 no.2
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• pp.145-154
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• 2011

This research was to examine the biological pollution class by color of the polluted section and calculate the biological pollution coverages of 9 stone heritages in Korea, from June to November 2008. Three storied stone pagoda in Mulgeol-ri, Hongcheon, Three storied stone pagoda in Suta Temple and Stupa to Hongudang in Sutasa Temple showed 90% biological pollution coverage and each stone cultural heritages showed 15~23% range of Bryophyte coverage, proving severe biological pollution. The Four-lion three storied stone pagoda of Gwaeseok-ri, Three storied stone pagoda in Suta Temple and Stupa to Hongudang in Sutasa Temple showed the worst biological pollution class by color of class 5. Three storied stone pagoda in Chang-ri showed satisfactory level of class 2. The result of the correlation analysis between biological pollution class and the biological pollution coverage of lichen showed high correlation coefficient of 0.91, however, the correlation analysis between biological pollution class and bryophyte or aerial algae coverage showed the low correlation coefficient. Eight taxa among all the aerial algae, Cosmarium decedens, Chlorella ellipsoidea, Anabaena fertilissima, Botryococcus braunii, Chroococcus turgidus, Navicula cryptocephala and Xenococcus acervatus showed high correlation coefficient of 0.56~0.85 with biological pollution coverage of bryophyte, in the correlation analysis. The correlation coefficient between biological pollution coverage of lichen, Trebouxia sp. and Chroococcus varius, had a range between 0.43 to 0.50. The correlation coefficient between biological pollution coverage of aerial algae, Achnanthes laterostrata and Ulothrix zonata showed a range of 0.57 to 0.76. Since the aerial algae with high correlation between biological pollution coverage showed clear appearance tendency, they can be used as indicator.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.11
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• pp.780-785
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• 2012

Existing states of attached algae in the sedimentation basin was observed during late april to early october, and the attached algae were visible 7 days after of cleaning the trough and the communities of algae became larger with increasing the operation periods. Attached algae community included bluegreen algae (Oscillatoria sp.), diatom (Synedra sp.,) and green algae (Mougeotia sp., Oedogonium sp.) and suspended diatom (Stephanodiscus sp.) as well. Diatom (Cymbella sp., Navicula sp., Synedra sp. and Stephanodiscus sp.), green algae(Mougeotia sp. and Cosmarium sp.) and blue-green algae (Anabaena sp.) were detected in the effluent of sedimentation basin. The chlorophyll-a (chl-a)concentrations of algae community on a square centimeter after 14 and 28 days were distinctively different depended on the copper sulphate treatment. The concentration of chl-a were $4{\mu}g/L/cm^2$ and $19{\mu}g/L/cm^2$ for the copper sulphate treated water and $59{\mu}g/L/cm^2$ and $147{\mu}g/L/cm^2$ for the untreated water. Diatom algae fragments were observed in red-brownish sediments on the bottom of industrial water distribution basin and degraded blue-green and green algae formated organic sediments combined with oxidized iron.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.743-752
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• 2015

We studied the spatio-temporal microalgal (phytoplankton and benthic diatoms) and environmental changes of the Hajeonri intertidal zone from February to November 2014. Seawater and phytoplankton analysis were conducted all through the months. The species, composition and abundance of phytoplankton and environmental factors were measured. As a result, diatom was dominant among a total of 113 species identified. On a seasonal basis (Feb. May, Aug., Nov.), we carried out studies on benthic diatoms on the surface of the sediments and their habitats at nine stations on the transect line at Hajeonri at low tide. The grain of the surface sediments was mainly composed of sandy silt and sandy mud. Organic pollution level was low. Benthic microalgal biomass (chlorophyll ${\alpha}$) was high in the spring and summer. A total of 163 benthic diatom species were identified. Navicula sp.1 and Paralia sulcata were dominant over the study period. Five diatom species were observed both in water column and on surface sediment at the same time.