• Journal of Wetlands Research
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• v.14 no.1
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• pp.47-57
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• 2012

We have measured soil enzyme activities, which represent the rates of organic matter decomposition, in four riparian ecosystems in Korea. ${\beta}$-glucosidase, N-acetylglucosaminidase, phosphatase and arylsulfatase activities were determined in five occasions over a year period in soils of control plots and plots with invasive plants, namely Sicyos angulatus and Humulus japonicus. Significantly higher enzyme activities were found in soils with invasive plant in barren land, but the difference was season and enzyme-specific. Although it was not universal changes, the invasive plants appeared to accelerate organic matter decomposition in some disturbed riparian ecosystems.

• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.240-248
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• 1997

기존 연구 문헌의 고찰로 서울시 야생조류상의 현황 및 관리방안은 다음과 같이 결론지을 수 있다. 1. 서울시 야생조류상에 대하여 물새와 산새를 모두 연구한 결과가 아직 발표되지 않아 정확한 현황은 파악하기 어려우나 번식기에는 약 40 여종, 겨울철에는 40여종이 서식하는 것으로 볼 수 있으나, 앞으로 정교하며 지속적인 모니터링이 필요하다. 2. 도시림 뿐만 아니라 주변의 패치를 동시에 고려한 통합적 접근방식(intergrated approach)으로 도시림을 연구하여 관리해야 할 것이다. 3. 도시림의 면적은 도시림에 번식하는 야생조류의 종 수에 큰 영향을 미치는 지배적인 인자로써 도시림이 더 이상 다른 토지이용 형태로 전환되지 않도록 관리하는 것이 가장 기초적인 관리 지침이다. 4. 대면적의 숲이 세분화 될 경우, 여름철새의 번식에 지장이 있을 수 있으므로 대면적 숲의 세분화를 막아야 하며, 가능한 한 생태통로(eco-corridor)로 세분화 된 숲을 연결할 수 있는 기술을 개발해야 할 것이다. 5. 도시림에 생육하는 임목 중 대경급 임목은 나무구멍을 둥지자원으로 이용하는 조류의 중요한 은신처와 둥지이므로 대경급 임목을 대신할 수 있는 인공새집의 설치는 나무구멍을 둥지로 이용하는 조류의 번식 종 수를 높이는 방법이다. 또한, 도시림이 시민에 의해 과도하게 이용될 경우, 관목층이 제거되어 관목층을 둥지자원으로 이용하는 조류의 서식에 불리한 조건을 제공할 수 있으므로 등산로 주변에 관목성 수목을 밀식하여 등산로의 확폭과 파괴를 막아야 할 것이다. 풍부한 먹이 자원을 제공하기 위하여 관목층 보호를 꾀하고 임목의 조림과 무육에 힘써야 할 것이다. 6. 동일한 면적에서 번식 조류 종 수를 높이는 방법은 엽층의 피도량을 늘이는 것이다. 현재 서울의 도시림은 엽층의 분화보다는 우선, 피도량의 증가를 위해 노력해야 하며 후에 엽층의 다양성을 높여 산림의 수직적 구조를 다양하게 만들어야 할 것이다. 7. 들고양이와 들개에 의한 소형 조류의 피해가 늘고 있으므로, 야생조류의 천적인 들고양이와 들개를 구제해야 할 것이며, 이에 앞서 서식실태가 조사되어야 할 것이다. 8. 한각을 비롯한 지천의 하변에 서식, 월동하는 물새류와 서식지에 대한 연구와 관리가 시급히 이루어져야 할 것이다. 9. 산불방지와 도시림 정비의 일환으로 실시해 온 관목층과 낙엽 및 죽은 가지를 제거하는 비과학적인 관행과, 하천유지유량을 높이고 하변 정비 및 산불 방지으 ㅣ한 방편으로 진행된 하변 식생 제거는 전문가와 충분히 제고한 후, 없어져야 할 것이다.

• Journal of Wetlands Research
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• v.14 no.1
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• pp.139-146
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• 2012

Stream ecosystems carry out significant functions such as water purification, especially denitrification. However, rapid landuse change since industrialization has altered ecological functions of streams. In this study, we aimed to investigate denitrification rates and their determinant factors in streams with different landuse patterns, and how denitrification rates vary with microtopology within streams. Ten fifth streams of each landuse were selected, and each stream was divided into four microtopological sites within streams - riparian zone, subsoil, and both head and tail parts of sand bars. In situ denitrification rates and physicochemical properties of soil were examined. Denitrification rates of agricultural, urban, and forest streams were $289.62{\pm}70.69$, $157.01{\pm}37.06$, $31.38{\pm}18.65mg$ $N_2O-N\;m^{-2}\;d^{-1}$ respectively. There were no significant differences in denitrification rates depending on microtopology, but the rates in riparian zone were the highest, and the rates in the head parts of sandbars were lower than those of tail parts. The determinant factors for denitrification rates included water temperature, silt and clay contents of soil, inorganic nitrogen, and organic carbon, and these factors all showed positive correlations with denitrification rates. Through this study, we find that landuse pattern in watershed region affects denitrification rates that is one of considerable functions of streams. In addition, estimation of denitrification rates taking into account for microtopology would contribute to developing ecological management and restoration strategy of streams.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.239-247
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• 2001

The Herbal Vegetation on Running Waterside in the Main Stream of Genmho River, Daegu and Gyeongsanbuk-do, Korea was investigated by the methodology from June to August of 1994 and analyzed distribution characteristics of vegetation that was related Water Environment. The vegetation is divided into 6 communities of Persicaria sieboldi-Persicaria hydropiper community, Persicaria thunbergii community, Impatiens textori community, Zizania latifoloa community, Phragmites communis community and Echinochloa crus-galli var. oryzicola community. A BOD and COD that indicate degree of contamination in water were showed 0.9 ppm and 1.6 ppm at upstream and 15.9 ppm and 24.8 ppm at downstream, respectively. The distribution patterns of vegetation have dominated by Impatiens textoricommunity in the upstream, by Persicaria sieboldi-Persicaria hydropiper community from upstream to mid-upstream, by Persicaria thunbergii community from upstream to midstream, by Zizania latifoloa community from nidstream to mid-downstream and by Phragmites communis community and Echinochloa crus-galli var. oryzicola community from mid-downstream to downstream. Especially, I suggested that Persicaria sieboldi-Persicaria hydropiper community and Persicaria thunbergii community will use as biotic indicator in water environment.

• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.131-137
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• 2002

This study was conducted to clarify the characteristics of bird community and habitat types in Mangyeong River area from Aug. 1999 to Jun. 2000. Paddy field was the most dominant land use type. Water area, mudflat, shrub field, urban area and green house were also dominant land use types in study area. Eighty-eight bird species were recorded during study period. Maximum number of species and individuals were shown as 58 species and 7,084 individuals in Oct. and Jan., respectively. There were low number of diving ducks and clumped pattern of waterfowl distribution of bird community in Mangyeong River area. Dabbling ducks distributed at upper reaches near Samrye Bridge, and plovers and sandpipers at lower reaches near estuary. Those results suggest that creation of pools over one meter water-depth and restoration of paddy field into riparian zone with diverse shrubs are required to increase the bird diversity in the Mangyeong rived.

• The Korean Journal of Ecology
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• v.25 no.2
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• pp.61-67
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• 2002

This study was conducted to clarify the characteristics of bird community and habita types in Mangyeong River area from Aug. 1999 to Jun. 2000. Paddy field was the most dominant land use type. Water area, mudiflat. shrub field, urban area and green house wee also dominant land use types in study area Eighty-eight bird species were recorded during study period. Maxiamum number of species and individuals were shown as 58 species and 7,084 individuals in Oct. and Jan. respecitvely. There were low number of diving ducks and clumped pattem of waterfowl distribution of bird community in Mangyeong River area. Dabbing ducks distributed at upper reaches near Samrye Bridge, and plovers and sandpipers at lower reaches near estuary. Those results suggest that creation of pools over one meter water-depth and restoration of paddy field freld into riparian zone with diverse shrubs are required to imcrease th bird diversity in the Mangyeong rived.

• Journal of Chest Surgery
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• v.37 no.8
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• pp.722-725
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• 2004

Mitral valve surgery is most commonly performed through the left atriotomy via the inter-atrial groove or trans-septal approach. An alternative method for approaching to the mitral valve is via the dome of the left atrium located between the ascending aorta and superior vena cava. Although this approach was described 30 years ago, it has not been popularized in mitral valve surgery. We introduce our recent experiences with mitral valve surgery carried out through the dome of the left atrium with brief review of literature.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.137-151
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• 2014

Various studies have been conducted to investigate effects of dams on river ecosystems, but less information is available regarding damming impacts on downstream denitrification. We measured denitrification enzyme activity (potential denitrification rate) and denitrifier abundances (using nirS, nirK, and nosZ as markers) in dammed headstreams of the Nakdong River in South Korea. Sediments in Phragmites-dominated riparian areas and in-stream areas across streams (dammed vs. reference) with different streambed materials (gravel and sand) were sampled occasionally. We hypothesized that (i) the higher available N and C contents in sediments downstream of dams foster larger denitrifier communities than in the reference system and (ii) differences in potential denitrification rates across the systems correspond with denitrifier abundances. Despite 30 years of different hydrological management with dams and greater inorganic N and DOC contents in sediments downstream of dams, compared to the references, abundances of denitrifier communities and potential denitrification rates within the whole sediment were not significantly different across the systems. However, nirS and nosZ denitrifier abundances and potential denitrification rates were considerably increased in specific sediments downstream of dams (gravelly riparian and sandy in-stream) with regard to flooding events and seasonal temperature variation. nirK was not amplified in all sediments. Canonical correspondence analyses (CCA) revealed that the relationship between abundances of denitrifier communities and nutrient availabilities and potential denitrification rates was a weak one.

• Journal of Wetlands Research
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• v.11 no.1
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• pp.123-130
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• 2009

Hyporheic zone is an area where hydraulic exchanges occur between surface water and ground water. Such transient area is anticipated to facilitate diverse biogeochemical reactions by providing habitats for various microorganism. However, only a few data are available about microbial properties in hyporheic zone, which would be important in better understanding of biogeochemical reactions in whole streams. The study site is Naesung stream, located in the north Kyoung-Sang Province, of which sediment is sandy with little anthropogenic impacts. Soil samples were collected from a transect placed perpendicular to stream flow. The transect includes upland fringe area dominated by Phragmites japonica, bare soil, and soil adjacent to water. In addition, soil samples were also collected from downwelling and upwelling areas in hyporheic zone within the main channel. Soils were collected from 3 depth in each area, and water content, pH, and DOC were measured. Various microbial properties including extracellular enzyme activities ($\beta$-glucosidase, N-acetylglucosaminidase, phosphatase and arylsulfatase), and microbial community structure using T-RFLP were also determined. The results exhibited a positive correlation between water content and DOC, and between extracellular enzyme activities and DOC. Distinctive patterns were observed in soils adjacent to water and hyporheic zone compared with other soils. Overall results of study provided basic information about microbial properties of hyporheic zone, which appeared to be discernable from other locations in the stream corridor.

• Journal of the Korean Home Economics Association
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• v.40 no.8
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• pp.13-21
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• 2002

본 연구의 목적은 유방절제수술을 받은 여성들을 위해 개발한 다섯 종류의 브래지어와 두 종류의 보정물 유형에 따른 착용감과 쾌적성을 검토하기 위한 것이다. 피험자로는 유방절제시술기간이 3년 이상이며 브래지어 사이즈 85에 컵사이즈 A컵인 여성 세 명을 선정하였다. 실험방법은 보정물을 삽입한 브래지어를 하루에 최소 15시간 이상 연속착용하도록 하고 실험복을 착용한 상태에서 피험자들의 일상과 그에 소요된 시간을 기록하도록 하였으며 이 때 착용한 브래지어와 보정물에 대한 느낌을 5점 척도로 표시하게 하였다. 실험기간은 다섯 종류의 브래지어를 하루에 한 가지씩 정해진 순서대로, 처음 5일은 옥보정물과 함께 착용하도록 하고 그 후 5일은 스펀지 보정물과 함께 착용하도록 하였으며 이러한 순서를 두 번 반복하게 하여 총 20일이 소요되었다. 각각의 피험자들에 대해서는 실험이 진행되는 동안 반복적인 면접을 통하여 진행상황을 기록하였으며 아울러 실험복에 대한 제언을 수렴하여 보다 나은 제품개발을 위한 기본 자료화하였다. 실험결과는 다음과 같다. 1. 브래지어에 있어서는 세 명의 피험자가 일치된 결과를 나타내어 일반적인 브래지어 형태와 가장 유사하면서 어깨 끈과 하변밴드 폭만 약간 넓혀준 실험복이 착용감에서 가장 높은 점수를 받았다. 착용자의 편의를 고려하여 앞트임으로 제작한 실험복의 경우에는 앞으로 구부렸을 때 밴드부분이 꺾이는 현상이 생겼으며 피험자들이 모두 뒤트임에 익숙하여 앞트임 브래지어 착용에 불편함을 나타내었다. 브래지어 착장평가에 있어서는 피험자들의 일상적인 행동이나 보정물의 종류가 영향을 미치지 않는 것으로 나타났다 2. 보정물 평가에 있어서는 모든 피험자가 옥가루 재질의 보정물만으로는 수술부위를 자극하는 느낌이 든다고 하였으나 3mm 두께의 스펀지와 함께 삽입했을 때는 아무런 문제가 없는 것으로 나타났다. 또한 보정물의 무게 조절이 가능하므로 실리콘재질의 보정물에서 쉽게 찾아볼 수 있는 무게에 대한 문제를 제기한 피험자는 없었다. 그러나 스펀지로 제작된 보정물에 대해서는 무게가 너무 가벼워 모든 피험자들이 양 쪽 가슴의 균형이 잘 맞지 않는다고 답하였으며 특히, 운동을 즐기고 활동이 많은 피험자의 경우 스펀지로 제작된 보정물에 대해 큰불만을 표시하였다.