• The Korean Journal of Malacology
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• v.12 no.2
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• pp.141-145
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• 1996

1996년 8월 춘천 의암호에서 채집한 긴애기물달팽이(Fossaria truncatula)를 재료로 공기건조법을 이용하여 통상적인 방법으로 염색체를 관찰하고 핵형을 분석하였다. 그 결과 긴애기물달팽이의 염색체 수는 2n=31, 32이었으며 15쌍의 배수체와 1개의 성염색체를 가지고 있었다. 핵형은 3쌍의 metacentric과 13쌍의 submetacentric 염색체로 구성되어 있었다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.112-113
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• 2000

산업이 발달하면서 비(雨)는 곧 산성비호 인식되어졌고, 불과 십수년 만에 산성비는 커다란 환경문제로 부각되었으며 이에 대한 많은 연구가 진행되어 왔다. 하지만 안개에 관한 연구는 안개의 특성상 발생일수 및 발생지역이 제한적이고, 채취가 어려워 국내에서는 연구가 활발하지 못한 실정이다. 이러한 이유로 북한강의 상수원인 의암호.소양호.춘천호에 인접한 춘천은 타 지역에 비해 연중 60 ~ 100일에 이르는 높은 안개 발생일수를 나타내고 있다(김만구 등, 1998).(중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.1
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• pp.91-100
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• 1985

This study is on the gate operation of dams, which are for the hydropower and multipurpose in Han River Basin, considering the safety under the emergency. The results of the study on the safety of dams in Han River Basin associated with the gate operation of dams against the design flood flow and the combined inflow are as follows; 1) The empirical formula (1) can be used for gate operation with the informations of reservoir's water level and the inflow. 2) The applicability of the multiple regression formula (2) among the gate opening area, inflow, water level, and outflow is assured. 3) From the safety analysis of dams for the emergency by the procedures developed in this study, six dams are safe except Soyanggang, Euiam, and Cheongpyung Dam, but the above three dams can be safe with the lowering of the starting water level of gate opening by the pre-discharges.

• The Korean Journal of Ecology
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• v.5 no.2_3
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• pp.132-135
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• 1982

Structure and dynamics of the phytoplankton communities of Uiam lake, Korea, was investigated. In the Uiam lake four dominant species were found Oscillatoria limosa at Chuncheon City side, O. tenuis at Soyang river side, Melosira italica at south-east side and Asterionella gracillima at west side of the lake. By cluster analysis, based on the similarity index and dissimilarity index, the phytoplanktons in this lake were grouped into three communities; i.e. Oscillatoria, Melosira and Asterionella community. And also the same groups obtained by the cluster analysis were recognized by polar ordination technique along polluted degree gradient. It is clear that oscillatoria community occur in polluted site, Asterionella community in unpolluted site and Melosira community in less polluted site.

• The Korean Journal of Malacology
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• v.2 no.1
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• pp.26-29
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• 1986

Corbicula fluminea, one of the 2 species in the family Corbiculidae living in the Lake Uiam, was used as an experimental material and the embryonic development and the structure of glochidia of this species were investigated. This freshwater mussels was oviparous, but some ovoviviparous: incubated their youngs in the inner-demibranchs or outer-demibranchs, however, chiefly used the inner-demibranchs as brood-pouch. The average time required from a fertilized egg to two-cell stage, veliger stage, and glochidium was 76 minutes, 3 hours, and 17 hours, respectively, The mean size of glochidium was $168{\mu}m$ in shell height, $195{\mu}m$ in shell lengh, $114{\mu}m$ in hinge legth and the form of glochidium was D-type and had no hooks or hooklets for attaching to fish like Unioidae.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.68-69
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• 2003

본 연구에서는 광역적 도시경관을 파악하기 위하여 수치표고모델과 토지이용 데이터를 이용한 CG화상을 작성하고 경관을 유형화하였다. 또한 각 유형의 시점장에서 도시중심에 위치한 봉의산을 시대상으로 하는 가시권 분석을 실시하였다. 춘천시의 도시경관은 3개 유형으로 분류되었다. 유형1은 개발제한구역 중심의 경관, 유형2는 녹지 중심의 경관, 그리고 유형3은 시가지와 수역을 중심으로 한 경관특성을 나타내었다. 가시권 분석의 결과, 유형1은 수역, 유형2와 유형3은 개발제한구역에서 피시빈도가 높았다. 특히. 시가지와 인접한 의암호가 경관상 중요한 곳으로 분석되었다. 또한 토지이용에서 개발제한구역이 경관상 중요한 곳에 분포하여, 개발제한구역의 해제 정도에 따라 대상지의 도시경관이 영향을 받게 될 것으로 사료된다.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2002.10a
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• pp.157-157
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• 2002

본 연구에서는 한강을 세 구간으로 구분하여 구간별 대표지점(의암호, 팔당호, 및 동호대교 정점)의 하상퇴적물을 grap으로 각각 채취한 후, Tandem Bioassays 을 적용하여 환경독성 수준을 평가하고 정점간 상호 비교하였다. Tandem Bioassays 이란 유해물질 오염에 의한 다양한 생태계 반응을 표현할 수 있는 최소한의 상호 보완적 환경독성 평가 체계를 의미한다. 본 연구에서 적용한 Tandem Bioassays 은 발광성미생물을 사용하는 Microtox 시험, 수서 물벼룩인 daphnia와 ceriodaphnia 시험, 그리고 개구리 배아를 이용하는 기형유발능 시험(최기형성 시험, FETAX)등으로 구성하였다.

• Korean Journal of Ecology and Environment
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• v.47 no.2
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• pp.116-126
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• 2014

To evaluate the relationship between dynamics of Cyanobacterial bloom and rainfalls, a monthly monitoring of water quality and phytoplankton from the three serial lakes (Lake Ui-am, Lake Chung-pyeong and Lake Pal-dang) in the North Han River System were examined 12 times from May 2012 to March 2013. A dense bloom of cyanobacterium Anabaena spp., was occurred over three lakes in the summer season of 2012. In Lake Ui-am, the Anabaena population appeared in June, showed a peak in July (43,850 cells $mL^{-1}$) and disappeared in November 2012. In Lake Chung-pyeong and Lake Pal-dang, Anabaena population commonly appeared in July, showed the peaks (31,648 cells $mL^{-1}$ and 7,136 cells $mL^{-1}$, respectively) in August, and entirely disappeared in September 2012. Over the three lakes, the phytoplankton community was commonly dominated by diatoms before Monsoon, cyanobacteria during Monsoon, and diatoms after Monsoon, respectively, indicating a Monsoon-dependent succession. A correlation analysis revealed that dynamics of Anabaena population was strongly related with rainfall (r=0.72, r=0.83, r=0.88, P<0.01 for three lakes), and partly with nutrients, inflow and outflow of lakes. Therefore, this study indicates that the outbreak and destruction of Anabaena bloom in North Han River System between 2012 and 2013 was impacted by rainfalls. However, a high density of cyanobacteria in Lake Ui-am remained after Monsoon, and thus, may paroduce bad-order and toxins from phytoplankton.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.79-95
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• 2017

Euiam and Paldang Reservoirs have often been facing water quality problems, such as eutrophication, algal blooms and off-flavors by treated wastewater effluent (TWE) in the North-Han and the Han River basins, but little is examined on the direct biological effect of TWE. This study tested algal growth potential (AGP) of four TWEs discharged into Euiam and Paldang Reservoirs to evaluate water fertility in September 2014 and March and September 2015. Test alga was used Anabaena circinalis isolated from Paldang Reservoir. Mean concentration of T-N and T-P in TWEs was $3,956.7{\mu}g\;N\;L^{-1}$ and $50.8{\mu}g\;P\;L^{-1}$, and the proportion of $NO_3-N$ and $PO_4-P$ to the total fraction was 72.1% and 40.8%, respectively. Both N and P were high in TWEs, but much higher N than P concentration indicates strong P-limitation. As a consequence, the maximum AGP was determined by $PO_4-P$ concentration (r=0.998, p<0.01). Mean AGP value was $15.4mg\;dw\;L^{-1}$ among four effluents indicating its eutrophic condition. Due to the establishment of tertiary (advanced T-P) treatment method in the studied plants recently, P concentration was significantly decreased in TWEs compared to the years prior to 2012. However, P concentration seems to be still high enough to cause eutrophication and algal blooms. Therefore, wastewater treatment to P-free level needs to be considered if effluents are directly discharged into the drinking water resources.

• The Journal of the Petrological Society of Korea
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• v.10 no.2
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• pp.95-105
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• 2001

U-Pb age determination was performed on the zircon fractions separated from the metamorphic rocks of three locations of the Gyeonggi Massif. The ages obtained from the upper and lower intersections between concordia curve and discordia lines made of the zircon fractions separated from the rocks of each locality we: $2168\pm$24 Ma and $1227\pm$40 Ma for the Yongduri Gneiss Complex, $1955\pm$22 Ma and $493\pm$32 Ma for the Euiam Group, and $3712\pm$244 Ma and $1613\pm$51 Ma for the Yongmunsan Group (2$\sigma$ errors). The upper intercept ages from the Yongduri Gneiss Complex and the Euiam Group of Gyeonggi massif are very similar to those obtained from the granitic gneisses and the porphyroblastic gneisses of Yeongnam massif respectively. Such similarities suggest that Gyeonggi and Yeongnam massifs might situate under the similar tectonic and geographic environment during ca. 2.2-1.9 Ga. The upper intercept age of Youngmunsan Formation (3.7 Ga) shows large error, because most of the zircon fractions are plotted very close to the lower intersection. It is necessary to investigate further to confirm this age. However, It may suggest the possibility of occurrence of the oldest crust of the northeast Asia similar to the one reported recently from the northeast China. The lower intercept age of the Yongmunsan Group is interpreted to indicate strong metamorphism. Such age postdates the 1.85-1.7 Ga metamorphism and igneous activities occurred in the Yeongnam massif, which might record the late Paleoproterozoic tectonic activities simultaneously occurred in both massifs.