• 생태와환경
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• 제44권2호
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• pp.155-171
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• 2011

The research assessed water quality using physico-chemical factors, trophic status index and attached diatom index in 10 reservoirs located in Chungcheongnam-do from October 2007 to June 2008. The physico-chemical water quality assessments revealed that Dangjin-gun (St. 1~5), which displayed a high chemical oxygen demand (V and VI) and chlorophyll-${\alpha}$ (Eutrophic-Hypereutrophic), was more polluted than Yesan and Cheongyang-gun. The sample were also hypereutrophic [trophic status index (TSI) 74.6] and ${\beta}$-mesosaprobic [diatom assemblage index to the organic water pollution (DAIpo) 44.47]. Yesan and Cheongyang-gun. Which were mid-level in their pollution status, were eutrophic (TSI 56.9) and ${\alpha}$-oligosaprobic (DAIpo 60.11). TSI correlated strongly with the attached diatom index (of DAIpo 0.60~0.62, and trophic diatom index of 0.72~0.74). Hence, the attached diatom index can be used with the trophic status assessment of lakes using TSI, and lake trophic status index (LTSI).

• 환경생물
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• 제42권2호
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• pp.158-171
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• 2024

Diatoms, which are reported to have over 18,000 species worldwide and approximately 2,400 species in Korea, can be found in various environments including freshwater, seawater, and wetlands. They are particularly valuable for understanding global environmental changes throughout history due to their ability to maintain their shape for extended periods of time. Instead of collecting floating diatoms using nets, low-layer substrates such as gravel and leaves, as well as sedimentary surface layers, were gathered in order to identify attached diatom species. This is because attached diatoms demonstrate higher species diversity compared to floating diatoms. In this study, seven previously unrecorded diatoms were discovered in various domestic freshwater environments. Two species were found in reservoirs (Eunotia yanomami, Gomphonella pseudookunoi), two in parasitic cones (Eunotia karveerensis, Luticola minor), two in rivers (Cavinula maculata and Prestauroneis integra), and one (Surirella brebissonii var. kuetzingii) in a lagoon. The shapes, structures, and morphological characteristics of each diatom were identified using electron microscopy.

• 한국패류학회지
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• 제29권3호
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• pp.197-205
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• 2013

Even though seedling production of Haliotis discus hannai has fully developed, the culture of benthic diatom as a live food for larvae is still a barrier to solve in commercial hatchery. The farmer depends on mixed microalgae which are non-selectively attached on the plate by flowing of natural seawater. The adequate diatom on the plate for the larvae in terms of quality and quantity is always significant bottleneck in the hatchery. In this study, two benthic diatom species, Caloneis schroederi and Rhaphoneis sp. were separately cultured in mass and inoculated to four tons' settlement tank of the larvae. And the larvae and the spats were cultured for nineteen and nine weeks, respectively. The result on seedling production of H. discus hannai with this method was compared to that of the farmer's traditional method as a control. With regard to variation of species composition of benthic diatom on the plate, C. schroederi and Rhaphoneis sp. were dominant for first three weeks after inoculation. But the diverse diatoms mainly, Navicula, Amphora, Cylindrotheca, Licmophora, Pleurosigma began to attache on the plate from the 4th week. The larvae attached 2.5 times more in C. schroederi tank than in the control tank. The final total biomass of the seeds in Rhaphoneis sp. tank was 3.2 times more than that of the control tank. The retared-spats in the seedling production also showed significantly higher growth and survival in the spat fed Rhaphoneis sp. or C. schroederi than those in the control group. We suggest that C. schroederi is proper for settlement of the larvae and Rhaphoneis sp. is appropriate for the growth of the larvae and spats in the commercial hatchery of H. discus hannai.

• ALGAE
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• 제19권4호
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• pp.311-320
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• 2004

A great portion of the marginal zone in Lake Gocheonam was covered with reed plants. Algae attached to the reed stems were exclusively composed of diatoms. Sixty-six species of diatoms were encountered in a floral survey. The important species were Nitzschia liebetruthii Rabh., Nitzschia acicularis (Ku¨tz.) W. Sm., Navicula gregaria Donk., Cocconeis placentula var. lineata (Ehr.) V.H. etc. Among the diatom flora, six species - Navicula nivalis Ehr., Navicula recens Lange-B., Nitzschia angustatula Lange-B., Nitzschia compressa (Bail.) Boyer, Nitzschia lanceola var. minutula Grin. and Surirella crumena Bre´b. - were recorded in Korea for the first times. Life forms of the reed-attached diatoms were simply prostrate. The biomass of epiphytic algae ranged from 0.05㎍ chl-$\alpha$ cm$^{-2}$ to 2.32$\mu$g chl-$\alpha$ cm$^{-2}$. The algal biomass of dead stems was higher than that of the living stems, and their flora were rich. The algal biomass reached a maximum in the spring after the death of the reed plants. The reed plants exhibited rich diatom flora and significantly high algal biomass on their stems to have taxonomical and ecological importance in the freshwater.

• 대한환경공학회지
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• 제34권11호
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• pp.780-785
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• 2012

침전지 구조물에서의 조류 부착현상은 4월말에서부터 10월초까지 나타났고, 침전지 청소 7일 후부터 부착조류가 관찰되었으며, 운전기간이 경과할수록 부착조류의 양은 점진적으로 증가하였다. 부착 조류 종들은 남조류인 Oscillatoria sp.와 Phormidium sp., 규조류 인 Synedra sp., 녹조류인 Mougeotia sp.와 Oedogonium sp.가 관찰되었으며, 부유성 규조류인 Stephanodiscus sp.도 부착조류의 군집에서 자주 관찰되었다. 침전지 월류 조류 종들은 규조류인 Cymbella sp., Navicula sp., Synedra sp.와 Stephanodiscus sp.가 관찰되었고, 녹조류의 경우는 Mougeotia sp.와 Cosmarium sp., 남조류는 Anabaena sp.가 관찰되었다. 황산동의 투입효과를 살펴보기 위해 침전지 트러프의 단위 면적당($cm^2$) 부착조류의 농도를 조사한 결과, 황산동을 투입한 침전지의 경우는 침전지 청소 후 14일과 28일 경과 후에 단위 면적당 부착조류의 농도가 각각 $4{\mu}g/L/cm^2$와 $19{\mu}g/L/cm^2$로 나타나 조류 부착현상이 매우 더디게 진행된 반면, 황산동을 투입하지 않은 침전지의 경우는 침전지 청소 후 14일과 28일 경과 후의 부착조류 농도가 각각 $59{\mu}g/L/cm^2$와 $147{\mu}g/L/cm^2$로 나타나 시간의 경과에 따라 다양한 부착조류가 부착하여 성장하였다. 공업용수 처리수의 수질에 미치는 영향을 조사하기 위하여 공업용수도용 배수지의 침전물을 분석한 결과, 적갈색의 미세한 침전물들에서 규조류의 파편들이 검출되었으며, 녹조류와 남조류의 경우는 분해되어 침전물의 유기물 성분으로 존재하면서 산화철과 결합하여 침전물을 형성하였다.

• 수산해양기술연구
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• 제50권4호
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• pp.542-550
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• 2014

We investigated biomass, diatom species and fucoxanthin contents as cell growth, fatty acid and amino acid contents as nutritional composition of diatoms attached on plate to confirm effects of light emitting diodes (LEDs) due to block off natural light. In the single LED irradiation, biomass showed significantly higher to $30.0{\pm}6.48mg/m^2$ in white LED than that of others (P<0.05). The dominate diatom species was Navicula cancellata. Their lipid contents showed significantly higher to $112.9{\pm}19.23ug/mg$ dry matter (DM) in control than that of others LEDs. But eicosapetaenoic acid (EPA) contents showed significantly higher to $3.3{\pm}0.62ug/mg$ DM than others, but not significantly differed with natural control light treatment (P<0.05). And total protein contents are higher in control and blue LED light than that of others, but essential amino acid contents showed significantly higher to $3.2{\pm}4.8%$ in control (P<0.05). In mixing light with natural and LED light, biomass showed $2.6{\pm}0.22mg/m^2$ in blue LED (P<0.05). Fatty acids contents were not significantly differed with all treatments. Amino acid contents showed to $11.0{\pm}0.33ug/mg$ DM in white LED (P<0.05), but not significantly differed with others LED lights (P>0.05). Therefore, we could suggest that irradiation of blue LED in natural light very benefit to diatom culture for larvae of sea cucumber and abalone and do on.

• Ocean and Polar Research
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• 제44권2호
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• pp.161-177
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• 2022

Microalgae can attach to the surface of ships and then spread to various areas by means of ship transport. The introduction of invasive species through ships is recognized as a marine problem worldwide. Identification of attached microalgae is necessary to investigate such movement between countries through ships. In the present study, through analytical methods we reviewed research data to identify the taxa of domestic attached microalgae and assess the ecological impacts of such microalgae. A total of 87 genera and 153 species (143 species of diatoms, 10 species of cyanobacteria, and 4 genera of dinoflagellates) were identified as native attached microalgae in Korea, and diatoms accounted for 93% of the total. Most of these attached microalgae were identified through research on natural substrates such as seaweeds and bedrock, and some were also identified through experiments using artificial adherent plates. To date, there is no information on microalgae attached to international ships and introduced into Korea. Molecular genetic analysis and systematic management through on-site sampling of international ships, microscopic analysis, and meta-barcoding are necessary to assess the inflow and spread path of hull-attached marine alien species and evaluate the risk they pose to the domestic ecosystem.

• 한국물환경학회지
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• 제36권6호
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• pp.559-567
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• 2020

The abnomal responseses on growth and morphology of attached diatoms by various heavy metals were studied. Ulnaria ulna (Nitzsch) Compère was employed as experimental species and exposed to the five heavy metals such as Cu, Zn, Pb, Cd, and As with four concentrations (0, 0.01, 0.1, and 2 mg L-1), respectively. The samples of Ulnaria ulna were examined on the changes of cell growth and teratological forms on the 7th, 14th, 21th, and 28th day, respectively, after exposure to the heavy metals. The samples exposed to the highest concentration, 2.0 mg L-1, of all the heavy metals showed the most obvious decreases of growth. The samples exposed to Cd (μ=0.049day-1) and As (μ=0.048day-1) showed the highest decreasing rate of growth (p=0.021(Cd), p=0.002(As)) and the highest morphological changes of diatom valves were also samples exposed to Cd (10.41%) and As (10.13%) (p=0.009 (Cd), p=0.005(As)). In contrast, Pb induced the lowest decreasing rate (μ=0.090 day-1) and the least change in valve morphology (3.31%). The Cd and As showed relatively stronger effects on growth rates compared to Cu, Zn, and Pb. For the percentage of emergence of morphological species by the type, the highest percentage were observed in sampled exposed to type 1 (43.4%) and followed by type 2 (29.1%). The type 2 and 4 were most abundant in samples exposed to Zn and Pb while the type 3 was most abundant in Cd and As. The Cu induced only type 1, suggesting that the frequency of emergence of each type varied among hevay metals. This research suggests that the degrees of abnomal changes on growth rate and valve morphology of Ulnaria ulna can be used as a bioindicater species for heavy metal contamination in freshwater.

• 생태와환경
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• 제34권3호통권95호
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• pp.199-205
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• 2001

본 연구는 신천의 부착규조 군집을 분석하고 유기오탁을 판정하기 위해 5곳의 정점을 선정하여 1999년 4월,6월,9월, 12월에 총 4회 시료를 채집 및 조사하였다. 부착규조 군집은 총 74분류군으로 2목,3아목,8과 19속,68종, 4변종 및 2미동정종으로 구성되어 있다. 중심규조목은 5분류군이고, 익상규조목은 69분류군이었다. 우점종은 4월, 6월과 9월에 정점 1${\sim}$3에서 Nitzschia palea, 정점 4에서 Navicula saprophila, 12월에 정점 1에서 N. palea, 정점 2${\sim}$5에서 Navicula. subminuscula로 3분류군만이 조사되었다. 3가지 생태군 중 호청수성종은 1.5%이하였으며, 광적응성종은 0.7${\sim}$28.1%로 낮았다. 그러나 호오탁성종은 70.6${\sim}$99.3%로 매우 높았다. DAIpo 값은 조사동안 0.4${\sim}$15.3의 범위였다. 조사 계절별 DAIpo 값은 1999년 4월에 3.6${\sim}$13의 범위로 수질은 전체 정점에서 강부수성이였다. 6월에는 정점 1에서 15.3으로 ${\alpha}$-중부수성이었으나 만약 미동정종인 Navicula sp.가 호오탁성종으로 동정되면 DAlpo값은 3.5로 낮아진다. 이 결과 정점 1${\sim}$3까지 2.5${\sim}$3.5의 범위이고 정점 4와 5에서 10.7과 11.9로서 강부수성의 수질로 판정된다. 9월과 12월에는 DAIpo값이 각각 0.8${\sim}$4.3의 범위와 0.4${\sim}$6.1의범위로 유기오탁은 모두 강부수성으로 판정되었다. DAIpo 값에 의한 본 하천은 상류부터 하류까지 강부수성의 매우 오탁된 수질로 판정되었다.

• 한국패류학회지
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• 제19권2호
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• pp.95-106
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• 2003

The compositions of amino acid in 6 monocultured benthic diatoms used in aquaculture of Haliotis discus hannai were analyzed, and effects of 15 artificial synthetic amino acids on the settlement and metamorphosis of H. discus hannai larvae. Results showed that the content of L-aspartic acid was highest in all diatoms, and that of L-glutamic acid was second high. In experiment using settlement slat without benthic diatom attached, the highest settlement rate (33.3 ${\pm}$ 8.8%) was obtained with L-glutamic acid, and a higher value (16.7 ${\pm}$ 3.3%) was found with L-aspartic acid at 24 h after experimental commencement, compared to that of control (8.6 ${\pm}$ 5.1%). 80 h later the metamorphosis rates of L-glutamic acid (86.7 ${\pm}$ 10.7%) and L-aspartic acid (80.0 ${\pm}$ 3.3%) groups were higher than control group(0) and other amino acids significantly. The response rate of L-glutamic acid was the highest (62.0%), and those of L-aspartic acid (30.0%) and L-threonine (25.3%) groups were also significantly higher than control group. In the experiment using settlement slat with benthic diatom attached, the best effect of various amino acids on induction of larval settlement was obtained with L-glutamic (82.0 ${\pm}$ 6.9%) and L-aspartic acid (78.7 ${\pm}$ 5.1%) at 24 h after experimental commencement. The settlement rates of L-histidine, L-leucine, L-lysine, L-methionine, L-phenylalanine, and L-tyrosine groups were significantly lower than control group. The same differences in the metamorphosis rate at 56 h after experimental commencement and in the response rate were found. It should be noted that after 80 h the metamorphosis rates of L-histidine (74.0 ${\pm}$ 12.0%) and L-lysine (87.0 ${\pm}$ 8.8%) declined rapidly compared to those of 56 h (8.0 ${\pm}$ 12.0%; 7.7 ${\pm}$ 12.0%).