• Journal of Species Research
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• 제7권2호
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• pp.114-122
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• 2018

As part of a larger study of indigenous prokaryotic species diversity in South Korea, various samples from Namhangang were subjected to analyses. Fresh water, underwater sediment, and moss-inhabiting aerobic and anaerobic bacteria were isolated. 22 of the isolates were identified as unrecorded bacterial species in Korea that had ${\geq}98.7%$ 16S rRNA gene sequence similarity with published species. The aerobic strains isolated were Kurthia gibsonii and Massilia plicata. Also identified were four facultative anaerobic strains: Bacillus hisashii, Enterococcus rotai, Paenibacillus vini, and Pediococcus pentosaceus. 16 strictly anaerobic strains were identified as Bacteroides xylanolyticus, Carnobacterium maltaromaticum, Clostridium argentinense, Clostridium beijerinckii, Clostridium butyricum, Clostridium cavendishii, Clostridium diolis, Clostridium frigidicarnis, Clostridium perfringens, Clostridium saccharoperbutylacetonicum, Clostridium sphenoides, Clostridium subterminale, Cutibacterium acnes, Paraclostridium bifermentans, Prevotella paludivivens, and Romboutsia lituseburensis. Based on the examination of morphological, cultural, physiological, and biochemical properties of the isolates, descriptive information of these previously unrecorded species is provided here.

• 한국환경생태학회지
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• 제37권1호
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• pp.13-34
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• 2023

Many ecologists try to understand plant communities and societies' changing processes by interacting with environmental factors. Plant communities formed in the sidings of streams, which are more dynamic than forest vegetation, are closely related to the disturbance regime of streams. U. pumila, which forms communities at the edges of streams, is distributed over the central and northern regions of the Korean Peninsula. In this study, we intended to explain the regeneration of U. pumila communities in the upstream region of the Namhangang River. Heights from the stream surface to the mid-high points of communities increased when the age class of U. pumila communities increased. On the other hand, the height of U. pumila tended to increase and decrease as the age class increased. The richness (S), evenness (J'), diversity (H'), and maximum diversity (H'max) also showed a tendency to increase and then decrease as the age class increased. On the other hand, the number of stems per individual and density (D) decreased as the age class increased. Seedlings of U. pumila failed to regenerate in the communities at the intermediate or higher stage of the age class. Regeneration of seedlings occurred in the spaces formed by the flooding, which occurred periodically in streams. After regeneration, U. pumila communities grew like a single organism. On the other hand, the plant species consisting of U. pumila communities exhibited a process in which the S and H' increased and then decreased as they developed. In other words, we determined that the changes in the species compositions were associated with changes in each species' environment and community. A space where seeds can regenerate seedlings should be provided for the regeneration of U. pumila communities. In the mid/upstream region of the Namhangang River, where the present study focused, newly formed communities were rare because the space required to regenerate U. pumila ceased to exist. Accordingly, we suggest securing an appropriate space for the regeneration of seedlings to maintain the U. pumila communities in the upstream region of the Namhangang River.

• 동굴
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• 제4호
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• pp.3-9
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• 1996

Ondal cave is located in Ha-ri Yongchun - myon, Tanyang - gun, Chungchongbuk - do, which has its site at the valley of southern side of Namhangang which winds up to the southwest. Namsan is kurungbong which is at the mid - slope of the steep and high mountain, Songsan which is 427 m high above sea level, and shows the aspect of the limestone area, a rough and steep mountain one.(omitted)

• 한국어류학회지
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• 제26권3호
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• pp.153-158
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• 2014

한강납줄개 Rhodeus pseudosericeus와 묵납자루 Acheilognathus signifer의 속간 잡종으로 추정되는 개체를 한강 수계의 주천강에서 채집하였다. 잡종의 기원을 확인하기 위하여 형태적 특징과 mitochondrial cytochrome b (mt-cyb) gene을 조사하였다. 형태 형질 분석에서, 조사된 표본의 등지느러미의 반문, 체색, 체측 반점과 종대 무늬 등은 두 부모종의 중간적 형질을 보였다. 또한, 잡종 개체의 측선은 불완전하였고 측선유공린수는 부모종의 중간값을 보였다. mt-cyb gene 분석 결과 잡종 개체는 한강납줄개와 염기서열이 100% 일치하여 한강납줄개가 모계임이 밝혀졌다. 따라서 두 자료의 분석 결과 본 연구에서 조사한 개체는 한강납줄개와 묵납자루의 속간 자연 잡종 개체임을 확인하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.1387-1391
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• 2007

In this study, water quality prediction that is necessary to water quality forecasting system is performed using 2-D river analysis models RMA-2 and RAM4. RAM4 is suitable to water quality forecasting system cause it is possible to put in the pollutants as a mass type boundary condition. Instant injections of pollutants at Yongdamdaegyo Bridge in Namhangang River are simulated and the behavior of pollutant cloud is observed. The effects of water quality accident to Paldang 2 water intake plants in Paldangho Lake is analyzed with time variation. And extra flow simulation is performed for mitigation of pollution. Several cases of water quality forecasting system at home and abroad are investigated and the direction of water quality forecasting system is presented.

• Animal Systematics, Evolution and Diversity
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• 제39권3호
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• pp.123-126
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• 2023

Members of Allobathynella Morimoto and Miura, 1957 and Hangangbathynella Park and Cho, 2013 belong to the family Parabathynellidae Noodt, 1965 exclusively inhabit subterranean environments including caves, springs, and interstitial groundwater. Among them, two parabathynellid species, Allobathynella cheongdoensis Park and Cho, 2016 and Hangangbathynella taechooni Park and Cho, 2013, have been reported in the hyporheic zones of the Nakdonggang and Namhangang Rivers in South Korea, respectively. To evaluate gene markers as diagnostic characters, we determined mitochondrial cytochrome c oxidase subunit 1 (CO1) and nuclear 18S rDNA from the topotypes of two Korean parabathynellid species, and then analyzed the genetic divergence among the two parabathynellids and their congeners. Additionally, we provided their habitus photographs and a brief discussion of the usefulness of the two marker regions for both genera as DNA barcodes.

• 환경생물
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• 제32권4호
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• pp.363-370
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• 2014

생태계가 담당하는 기능의 크기와 그 변화에 관여하는 환경요인과의 상호관계성 도출은 생태계의 과학적 속성 이해에 필수불가결한 요소이다. 본 연구는 수변의 특이적 환경조건에 의해 주기적인 교란과 토양 퇴적환경이 발달하는 하천 수변지역에 형성되어 있는 하천식생에 대해 토양탄소축적량을 정량하고 그러한 식생의 토양으로부터 방출되는 토양호흡과 환경요소 자료를 수집하여 각 요소의 상호간의 관계성을 분석하였다. 남한강 여주지역에서 물억새, 달뿌리풀, 버드나무에서 토양호흡은 2009년 8월부터 11월까지 각 군락에서 수집하였으며, 토양탄소축적량은 각 군락의 3지점에서 수집하였다. 토양호흡은 지온변화에 민감하게 반응하였으며, 가장 높게 관찰되는 8월의 토양호흡값은 달뿌리풀군락, 물억새군락, 버드나무군락에서 각각 $1,539mgCO_2\;m^{-2}$, $1,200mgCO_2\;m^{-2}$, $1,215mgCO_2\;m^{-2}$으로 측정되었다. 이러한 자료를 바탕으로 산정한 연간 토양호흡량은 달뿌리풀군락, 물억새군락, 버드나무군락에서 각각 $19.8tCha^{-1}yr^{-1}$, $30.1tCha^{-1}yr^{-1}$, $22.0tCha^{-1}yr^{-1}$으로 산정되어 물억새군락의 토양에 가장 높은 탄소가 축적된 것으로 평가되었다. 한편, 토양탄소축적량 (리터층+토양층)은 달뿌리풀군락, 물억새군락, 버드나무군락에서 각각 $40.6tCha^{-1}$ (1.9+38.7), $46.9tCha^{-1}$ (43.0+3.9), $31.2tCha^{-1}$ (28.9+2.3)으로 물억새군락의 토양에 가장 많은 탄소가 축적된 것으로 조사되었으며 이는 물억새군락의 높은 지상부 생산성에서 기인하는 것으로 판단된다.

• 한국물환경학회지
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• 제36권5호
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• pp.392-404
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• 2020

The focus of this study was to quantify the thermal stratification and analyze the relationship between the stratification structure and the tributaries to understand flow variations in the Paldang Reservoir. The vertical distribution of the temperature and density gradients, and the depth and thickness of the thermocline were quantitatively calculated using a lake physics tool (rLakeAnalyzer) and high-frequency monitoring data. Based on a density gradient of 0.2 kg/㎥/m, the thermocline was formed from mid-May to early-September 2019 and the other periods were weakly stratified or mixed. The thickness of the thermocline was developed until 4.7 m and the depth of the thermocline was formed at a depth of 3 - 6 m at the front of the Paldang Reservoir. During the formation of the thermocline, the Namhangang and Gyeongancheon tributaries with relatively high water temperature (low-density) flowed into the upper layer of the reservoir, and the Bukhangang tributary with low water temperature (high-density) mainly affected the lower layer of the reservoir. This is because the density currents were formed due to the difference in the water temperature of the tributaries. The findings of this study may be used for constructing high-frequency monitoring and quantitative data analyses of reservoirs.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.302-306
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• 2010

전 세계적으로 진행 중인 지구온난화와 기후변화의 영향으로 우리나라의 강우특성이 변화하고 있다. 이에 기후변화로 인한 재해 발생요인을 감소시키기 위한 다양한 대책을 검토하고 합리적 대책을 제시하여 이상홍수에 대한 대응방안을 수립할 필요가 있다. 본 연구에서는 이상홍수에 대비한 방재대책을 수립하기 위해, 먼저 이상홍수 발생 시 댐과 같은 대규모 수공구조물의 방류로 인해 하류에 위치한 도시에 피해가 미칠 수 있는 유역을 선정하였다. 이후 선정된 시험유역에서의 이상홍수 발생 시나리오를 작성하여 각 시나리오별 이상홍수의 취약성을 평가하고, 마지막으로 시험유역에 다양한 방재대책을 적용해 적용된 방재대책의 재해저감 능력을 분석하여 적절한 방재 개선안을 도출하는 것을 목표로 하였다. 충주댐의 홍수조절 능력을 초과한 홍수발생 시 충주댐 하류에 위치한 주요 도시인 충주 및 여주에 홍수피해 발생 위험이 증가하게 된다. 본 연구에서는 2006년 7월에 발생했던 홍수사상을 분석하고, 2006년 7월의 실측 강우량보다 1.2~1.5배 큰 강우사상과 PMF가 발생할 경우에 대한 모의를 통해 남한강유역의 홍수 취약성을 분석하였다. 분석된 홍수 취약성을 기초로 충주댐 하류지역의 홍수피해를 줄이기 위해 다양한 홍수저감대책을 고려하였다. 홍수저감대책 중 구조적인 방법으로는 댐 상류지역에 홍수조절지를 건설하는 방안, 신규댐을 건설하여 충주댐과의 연계 운영하는 방안, 댐 하류에 강변저류지를 설치하는 방안 및 홍수발생시 파제를 실시하는 방안을 모의하였고 비구조적인 방법으로는 충주댐의 홍수조절능력을 높여주는 가변제한수위 적용방안을 모의하였다. 그 결과 댐 사이의 연계운영이 적절하게 이루어진다면 구조적인 방법 중 하나인 신규댐을 건설하는 방안이 가장 효과적인 홍수저감대책인 것으로 분석되었다.

• 한국물환경학회지
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• 제21권3호
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• pp.277-283
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• 2005

This paper aimed to compare the daily water quality as well as the hydrological data gathered for the past two years (2000 to 2001) between the two influent rivers of Paldang reservoir. The analysis also has been carried out to draw out the factors that affect the water quality at the dam site, where the main drinking water drawing point is located. The relationship between total amount of monthly rainfall and monthly inflow showed $r^2=0.74$ (p<0.05). The highest peak of inflow of influent rivers recorded in August and September (in the year of 2000) and July and August (2001). Average inflows of influent rivers in 2000 and 2001 are calculated at 209.0, 161.5 CMS (Bughangang), 268.6, 148.2 CMS(Namhangang), and 7.8, 5.0 CMS (Gyeongancheon). The formula which was driven from the relationship between inflow and COD load of influent rivers, explained that COD concentration in general increased with the inflow. But during the rainy seasons (July, August, and September), COD concentration decreased according to the increase of inflow. The daily rainfall and COD concentration(or load) during the rainy season (August and September in the year of 2000, July and August in 2001) indicated that the peak of COD load correspond with the rainfall, which decreased sharply after 3 or 4 days. The reason was thought that the high COD load was diluted rapidly by the rain flow. Water temperature, pH and conductivity measured at dam site decreased obviously when the inflow sharply increased. Peak period of total phosphorus concentration coincided with that of inflow. In rainy season, chlorophyll-a concentration decreased obviously as the inflow increased. The reason can be ascribed to the flushing effect caused by the operation of floodgate.