• 한국지구과학회지
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• 제29권5호
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• pp.396-407
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• 2008

Hydrogeologic properties of a well field around middle mountainous areas in Pyosun, Jeju volcanic island were examined based on water level monitoring, geologic logging and pumping test data. Due to the alternating basaltic layers with varying permeability in the subsurface, it is difficult to analyze the hydraulic responses to artificial pumping and/or natural precipitation. The least permeable layer, detrital materials with clay, is found at a depth of 200 m below surface, but it is not an upper confining bed for lower main aquifer. Nevertheless, this layer may serve as a natural barrier to vertical percolation and to contaminant migration. Water levels of the production wells are dominantly affected by pumping frequently, while those of the remote observation wells are controlled by ambient precipitation. Results of pumping tests revealed a possible existence of horizontal anisotropy of transmissivity. However, some results of this study include inherent limitations enforced by field conditions such as the consistent of groundwater production and the set of time periods for the cessation of the pumping prior to pumping tests.

• Animal Systematics, Evolution and Diversity
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• 제27권3호
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• pp.239-245
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• 2011

We describe and illustrate two pontoniine shrimps, Cuapetes grandis and Periclimenes ornatus, for the first time in Korea. C. grandis was collected in an artifical reef of Dadae, Geojedo Island by SCUBA diving in 15-20 m depth. This species was found in an oyster within an artificial reef and appeared to be free-living. P. ornatus was collected from Seongsanpo, Jejudo Island by SCUBA diving in 10 m depth. This species had a symbiotic relationship with sea anemone. This record extends their previously known range from southern Japan to the Korean peninsula and the number of known pontoniine species in Korea to four.

• Journal of Ecology and Environment
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• 제44권4호
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• pp.207-211
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• 2020

Adult land crabs generally live on land while their larvae live in the sea. In the case of Sesarma haematoche, female crabs migrate from land to sea to release the larvae at the high tide of syzygy night. Artificial structures along coastal areas are being obstacles for the migration of land crabs and causing synchronized roadkills on coastal roads during breeding migration. In this research, we compared the sex ratios of crab populations in coastal areas with coastal roads and uninhabited island areas with no road. The proportion of females in inland habitats with coastal roads was significantly smaller than island habitats. In particular, females are exposed to the risk of annually repeated roadkills, and the proportion of females decreases rapidly with their growth. If this tendency is general for land crab populations in the coastal areas with roads, significant road mortality of female land crabs during breeding migration can lead to severe population decline in coastal areas. Therefore, it is necessary to take an action to save land crabs crossing coastal roads.

• 한국해양생명과학회지
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• 제6권2호
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• pp.117-123
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• 2021

Post-disturbance recovery pattern of subtidal soft corals-macroalgae mixed community and the role of water depth were investigated. The experiment was conducted in a subtidal rock wall of Munseom, Jeju Island, Korea for 2.5 years. Artificial disturbance was done at established treatment plots at depths of 10, 15 and 20 m and were then compared with undisturbed control plots. After disturbance, recovery of soft corals was very slow, whereas macroalgae quickly occupied the plots and reached a similar level as the control in 6 months, and this pattern was consistent at all water depths. This unbalanced speed of recovery caused higher macroalgae establishment than soft corals in treatment compared to control plots, indicating a possible phase shift in the community structure. This study provides an important implication for the necessity of monitoring the influence of disturbance at a larger scale, from a conservation perspective of soft corals in Jeju coast.

• 한국환경복원기술학회지
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• 제22권5호
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• pp.57-67
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• 2019

Water-Birds are the birds that occupy the highest proportion in Korea, inland wetlands and reservoirs provide them with a good environment as habitat, but their habitats have been losing because of thoughtless development. Therefore, artificial plant islands in reservoirs are important for improving habitat environment and providing food resources. However, there are no research and standards on the built and management of artificial plant islands. So this study is to find out the density of bird using artificial plant island as habitat through monitoring using UAV focus on the Cheonho-reservoirs located in Seobuk-gu, Cheonan-si(Middle Chungcheong Province). Further, the correlation analysis with environmental factors was conducted to determine the effect of artificial plant islands as habitats for water-birds. The supervised classification of the three-time images taken by the drone identified 244 white-billed ducks and 46 mandarin ducks. The utilization rate was different for each photographed date, and more individuals were identified in wet artificial plant islands than dry ones. As a result of analyzing the utilization follow environmental factors, the distance from the trail showed a significant correlation, and the other factors did not have a statistically significant effect. This study is the first case of the UAV monitoring method of the water-birds using artificial plant islands in the reservoir, and can be used as the basic data for the built and management.

• 한국전통조경학회지
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• 제33권4호
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• pp.87-98
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• 2015

제주도 평대리에 위치한 천연기념물 374호, 비자나무림에 대해 식물사회학적 방법 및 수리적 분석에 의한 연구가 이루어졌다. 본 연구의 목적은 비자나무림이 가지는 생태적 특성을 규명하는데 목적을 두고 있으며, 한반도 내 공간적 분포특성을 파악하고 비교하고자 하였다. 국내외 지역에 분포하는 식생대와의 상관관계 분석을 위해 NMDS와 집괴분석법이 활용되었다. 제주 평대리 비자나무림은 12개의 식물사회학적 조사표를 바탕으로 비자나무-상산군락으로 분류되었으며, 서식처 환경을 반영한 전형하위군락과 가는쇠고사리하위군락으로 구분되었다. 또한 식생의 서식처 특성과 비자나무림 발달에 근거를 제공하는 추가적인 진단종군(꽝꽝나무, 단풍나무, 양하, 산쪽풀, 긴사상자, 처녀이끼 등)이 제안되었다. 제주도 내 동일식생대 식생의 종조성 분석 및 국내 기타 비자나무림들과의 좌표결정과 집괴분석 비교를 통해서 평대리 비자나무림은 종조성 및 식생구조에 있어서 매우 독립적인 특성을 나타내고 있는 것으로 확인되었다. 국외 비자나무림과의 비교에서 평대리 비자나무림이 가지는 특성이 확인되었으며, 자생지와는 종조성 및 식생유형에서 많은 차이를 보이는 것으로 밝혀졌다. 평대리 비자나무림에 대한 식물생태학적 평가가 이루어졌으며, 국가중요자연자원에 대한 평가규정에 대해 고찰하였다.

• 한국터널지하공간학회 논문집
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• 제17권2호
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• pp.153-166
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• 2015

일반적인 장대 철도터널에 비해 해저터널은 환기 및 방재를 위한 별도의 연직갱 또는 경사갱 설치에 공간상 많은 제약을 받게 되므로, 인공섬을 건설하여 환기를 수행할 필요가 있다. 그러나, 인공섬 설치에는 시공상의 문제 뿐만 아니라 건설비용이 증가하게 되므로, 인공섬 설치를 최소화하여 환기구간 거리를 늘려야 한다. 이에 따른 환기거리의 증가시, 누풍에 의한 신선공기 공급량이 커지게 된다. 공급풍량이 과대해지면, 구조물 한계에 의해 설치가능한 덕트직경이 제한적이므로, 팬 정압 및 동력도 상당히 증가하게 된다. 따라서, 초장대 해저터널을 건설하기 위해서는 이러한 현실적인 문제를 극복하고, 시공중 터널내 환경을 쾌적한 상태로 유지할 수 있는 기술력이 필요하다. 본 논문에서는 이러한 초장대 해저터널에 적합한 공사중 환기 방식을 개발하기 위한 기본연구로써, 국내외의 공사중 환기용량 산정방법 비교를 통해, 스위스의 SIA 196 코드가 초장대 해저터널계획에 적합함을 확인하였다. 또한, 덕트 접속부의 누출에 관한 실험을 통해, 국내의 덕트 접속방식은 100 m당 누풍율이 1.5~3.0% 사이임을 확인하였다. S등급 덕트의 경우 환기가능거리가 10.2 km 이므로, 덕트의 접속방법을 개선한다면, 환기가능거리는 더 길어질 수 있다. 따라서, 공사중 덕트의 누풍개선이 초장대 해저터널의 공사중 환기의 주요 이슈임을 확인하였다.

• 생태와환경
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• 제41권spc호
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• pp.93-98
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• 2008

인공식물섬의 BOD, SS, T-N, T-P제거효율과 조류의 성장억제 능력을 분석하였으며 조류제어효과에 있어서 미생물보유활성화, 식물의 흡수효과에 대한 각각의 효과성을 판단하기 위해 구성요소별 장치를 구성하여 실험하였다. 구성요소별 장치는 (1) Blank Test, (2) 인공식물섬(VAFI) $0.25m^2$, (3) 식물을 식재 하지 않은 인공식물섬(AFI) $0.25m^2$, (4) 인공식물섬을 수면위로 부유시키기 위한 부력재 $0.25m^2$, (5) Media (부력재 $0.25m^2$에 50cm 길이로 Media를 4줄 부착)이다. BOD제거는 VAFI, AFI, 부력재, Media에서 각각 82.7, 80.8, 45.2, 59.6%로 나타났다. T-N제거는 VAFI, AFI, Media에서 각각 51.2, 31.7, 25.1%로 나타났다. T-P제거는 VAFI, AFI, 부력재, Media에서 각각 23.3, 16.7, 10.0, 13.3%로 나타났다. 엽록소-${alpha}$는 VAFI에서 97.9%가 제거되었다. VAFI의 구성 요소별 제거율은 차광효과 35.1%,미생물의 복합작용에 의한 효과 61%, 식물과 뿌리에 의한 효과 1.8%인 것으로 나타났다.

• 한국해양학회지:바다
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• 제11권4호
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• pp.165-171
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• 2006

본 연구는 비교적 저농도로 오염된 하천수를 대상으로 phytoremediation 기법으로 정화방안을 제시하고자 수행되었다. 온실에 식물 반응조를 설치하여 해바라기 일종인 Heilianthus annuus의 성장에 따라 영양염의 처리량을 산정하였다. 또한 현장 적용성을 검토하기 위하여 H. annuus을 식재한 인공부도(artificial floating island)를 관개수로에 설치하여 식물의 질소, 탄소 및 수소 함유량 증가를 확인하였다. 실험결과 7월부터 9월에 이르기까지 유입수 용존 무기질소(DIN)의 농도를 $28.5\sim199.2mg/l$, 유입수 용존무기인(DIP)의 농도를 $13.3\sim25.4mg/l$ 까지 변동 시켰을 때, 농업용수 기준보다 매우 높은 고농도임에도, 식물체의 성장장해는 나타나지 않았다. 이때 DIN 제거율은 평균 3일의 체류시간에서 $81.7\sim98.6%$였으며, DIP 제거율은 $81.9\sim98.4%$로 나타났다. 또한 효율적인 처리기간은 48시간으로 확인되었다. 인공부도에 식재한 H. annuus의 질소, 탄소 및 수소의 함유량을 보면 질소의 경우 줄기에서 $3.2\sim7.8%$, 뿌리에서 $3.0\sim6.3%$를 보였다. 탄소는 줄기에서 $40.1\sim57.7%$, 뿌리에서 $43.4\sim53.8%$의 함유량을 보였다.

• 한국환경복원기술학회지
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• 제9권2호
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• pp.23-32
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• 2006

Total suspended solids (TSS), five-day biochemical oxygen demand ($BOD_5$), total nitrogen (T-N), and total phosphorous (T-P) concentrations around and under a floating island were examined from October 2002 to September 2003. The island was installed in July 2002 on the surface of an agricultural irrigation reservoir located in the southern part of the Korean Peninsula. It was composed of six polyethylene panels. Each panel was 2 m (length) ${\times}$ 1 m (width) ${\times}$ 0.02 m (thick) and had about thirty-two holes each with a diameter of eight centimeters, through which plant roots grew down into the water. Coconut fibers of nine-centimeters in height were placed on the panel, which sustained plants rhizomes and roots. Both the fibers and the panel were raped with polyethylene wire mashes. About thirty irises (Iris pseudoacorus) were planted into the fibers of each panel. The concentrations of TSS, $BOD_5$, T-N and T-P below the island during the iris-growing season averaged 9.70, 2.59, 3.61 and 0.14 mg/L, respectively and those around it averaged 9.99, 2.83, 4.07 and 0.16 mg/L, respectively. The average concentrations of TSS, $BOD_5$, T-N and T-P below it during the iris non-growing season were 8.68, 2.37, 3.25 and 0.14 mg/L, respectively and those near it were 8.76, 2.43, 3.34 and 0.15 mg/L, respectively. At a significance level of ${\alpha}$=0.05, $BOD_5$, T-N and T-P concentrations under the island during the iris-growing season were significantly low when compared with those around it except TSS. No differences in TSS, $BOD_5$, T-N and T-P concentrations between around and near it were found at a significance level of ${\alpha}$=0.05 during the iris non-growing season. The removal of $BOD_5$, T-N, and T-P during the growing season were significantly high when compared with those during the non-growing season. TSS abatement of the floating island was very low during both the growing and non-growing seasons. The island's reductions of $BOD_5$, T-N and T-P were good during the growing season, especially T-N and T-P, which have been considered as primary pollutant sources causing the water quality degradation of reservoirs. The removal of T-N and T-P was primarily attributed to the absorption of nitrogen and phosphorous by the irises during the growing season.