• 한국해양공학회지
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• 제32권2호
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• pp.123-130
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• 2018

The present study investigated the validity of an equilibrium shoreline empirical formula for real phenomena. Among three types of equilibrium shoreline formulas, Hsu's parabolic type static formula was employed, which is well-known and the most practical for shoreline estimation after coastal or harbor structure construction. The wave data observed at Maengbang beach and the CERC formula on longshore sediment transport were used in the present investigation. A comparison study was only conducted for the case of a shoreline change after the construction of a groyne. Reasonable agreement was seen between the observed wave data and the data obtained under a wave angle spreading function S = 3.5. However, significant changes were observed when S increased. Thus, careful application is required when using Hsu's formula.

• 한국환경복원기술학회지
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• 제5권2호
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• pp.1-8
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• 2002

The aim of this study was to generate systemic data for the aquatic plant distribution according to water depth and crossing slope in the shoreline. The results of this study were as follows; 1. Anxiety to 0 near area Bidens frondosa, Scirpus tabernaemontani, Carex dispalata etc. total class 21 observe, and Phragmites communis, Iris pseudoacorus etc. class 6 of anxiety 0-70cm extent examined. Class 21 of anxiety observed all such as Bidens frondosa, Scirpus tabernaemontani, Carex dispalata in near area to 0, and Phragmites communis, Iris pseudoacorus etc. class 6 of anxiety 0-70cm extent examined. Anxiety 70-100cm extent Nymphoides indica, Ttapa japonica etc.. class 2 appeared to line Zizania latifolia, Typha angustata back 2 papers, 130cm and examined that Nelumbo nucifera was limit anxiety state 230cm. 2. Aquatic plants of Phragmites communis, Zizania latifolia, Typha angustata etc. range mainly to gentle gradient of slant 10 degree low and distribution pattern was ranging by Zizania latifolia, Typha angustata, Phragmites communis period of ten days from deepwater place. Nelumbo nucifera was forming become independent stock keeping away invasion of plant that ability to breed was different because was prosperous. Slant 10 bores was growing near sleep in been strange steep slope earth and distribution of emerged plant appeared punily and emerged plant and swampy land plant were ranged extensively in gentle gradient of 10 degree low. 3. On lake surrounding plant when wish to do distribution of natural conditions reference need to. That is, gentle gradient and distribution form of steep slope earth are different, and same pitch must consider enough this because appear as distribution, distribution according to that some plant species were growing was different.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.271-281
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• 2019

Background: The plant communities within reservoir drawdown zones are ecologically important as they provide a range of ecosystem services such as stabilizing the shoreline, improving water quality, enhancing biodiversity, and mitigating climate change. The aim of the study was therefore to identify the major environmental factors affecting these plant communities within the drawdown zone of the Soyangho Reservoir in South Korea, which experiences a monsoonal climate, and thereafter to (1) elucidate the plant species responses and (2) compare the soil seedbank composition along main environmental gradients. Results: Two main environmental gradients affecting the plant community structure were identified within the drawdown zone; these were a vertical and longitudinal gradient. On the vertical dimension, a hydrological gradient of flood/exposure, the annual-dominated plant community near the water edge changed to a perennial-dominated community at the highest elevation. On the longitudinal dimension from the dam to the upstream, plant species composition changed from an upland forest-edge community to a lowland riverine community, and this was correlated with slope degree, soil particle size, and soil moisture content. Simultaneously, the composition of the soil seedbank was separated along the vertical gradient of the drawdown zone, with mainly annuals near the water edge and some perennials at higher elevations. The species composition similarity between the seedbank and extant vegetation was greater in the annual communities at low elevation than in the perennial communities at higher elevation. Conclusions: The structures of plant community and soil seedbank in the drawdown zone of a monsoonal riverine reservoir were changed first along the vertical and secondly along the longitudinal gradients. The soil seedbank could play an important role on the vegetation regeneration after the disturbances of flood/exposure in the drawdown zone. These results indicate that it is important to understand the vertical and longitudinal environmental gradients affecting shoreline plant community structure and the role of soil seedbanks on the rapid vegetation regeneration for conserving and restoring the drawdown zone of a monsoonal reservoir.

• Journal of Ecology and Environment
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• 제39권1호
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• pp.17-29
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• 2016

We conducted the study on the relationship between the distribution of coastal sand dune plants and edaphic factors from the shoreline to inland in sand dune ecosystem. The application of TWINSPAN classification based on 10 species, led to the recognition of three vegetative groups (A-C), which associated with their habitats (foredune, hummuck in semistable zone and stable zone). The associations were separated along soil gradient far from the seashore. The relationships between species composition and environmental gradients were explained by canonical correspondence analysis (CCA). Distance from the shoreline was an important indicator to determine soil properties (pH, total ion contents, sand particle sizes, organic matters and nitrogen contents) from the seaward area to inland area and distribution pattern of coastal sand dune plants. Group A is foredune zone, characterized by Calystegia soldanella; group included typical foredune species such as Elymus mollis, Carex kobomugi, Ixeris repens, C. soldanella and Glehnia littoralis. Group B on semi-stabilized zone was characterized by Vitex rotundifolia, a perennial woody shrub. This group was associated the proportion of fine sand size (100 to 250 μm). The results on the proportion of soil particle size showed a transition in sand composition, particularly with respect to the proportion of fine sand size that occurred from the foredune ridge at 32.5 m to the Vitex rotundifolia community at 57.5 m from the shoreline. Group C on stabilized zone was characterized by Zoysia macrostachya, Lathyrus japonicus and Cynodon dactylon and were associated soil organic matter and nitrogen contents. The spatial distribution of plants in the Goraebul coastal sand dune system may result from the interactions between the plant species and environmental heterogeneity.

• 환경영향평가
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• 제11권2호
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• pp.79-91
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• 2002

Four dimensional data assimilation (FDDA) technique was considered for 3 dimensional wind field in coastal area and a set of 3 numerical experiments including control experiments has been tested for the case of the synoptic weather pattern of the weak northerly geostrophic wind with the cloud amount of less than 5/10 in autumn. A three dimensional land and sea breeze model with the sea surface temperature (SST) of 290K was performed without nudging the observed wind field and surface temperature of AWS (Automatic Weather System) for the control experiment. The results of the control experiment showed that the horizontal temperature gradient across the coastline was weakly simulated so that the strength of the sea breeze in the model was much weaker than that of observed one. The experiment with only observed horizontal wind field showed that both the pattern of local change of wind direction and the times of starting and ending of the land-sea breeze were fairly well simulated. However, the horizontal wind speed and vertical motion in the convergence zone were weakly simulated. The experiment with nudgings of both the surface temperature and wind speed showed that both the pattern of local change of wind direction and the times of starting and ending of the land-sea breeze were fairly well simulated even though the ending time of the sea breeze was delayed due to oversimulated temperature gradient along the shoreline.

• 한국환경과학회지
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• 제19권6호
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• pp.689-701
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• 2010

The effects of high-resolution wind profiler (HWP) data on the wind distributions were evaluated in two different coastal areas during the study period (23-26 August, 2007), indicating weak-gradient flows. The analysis was performed using the Weather Research and Forecasting (WRF) model coupled with a three-dimensional variational (3DVAR) data assimilation system. For the comparison purpose, two coastal regions were selected as: a southwestern coastal (SWC) region characterized by a complex shoreline and a eastern coastal (EC) region surrounding a simple coastline and high mountains. The influence of data assimilation using the HWP data on the wind distributions in the SWC region was moderately higher than that of the EC region. In comparison between the wind speed and direction in the two coastal areas, the application of the HWP data contributed to improvement of the wind direction distribution in the SWC region and the wind strength in the EC region, respectively. This study suggests that the application of the HWP data exerts a large impact on the change in wind distributions over the sea and thus can contribute to the solution to lack of satellite and buoy data with their observational uncertainty.

• 지구물리
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• 제6권3호
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• pp.139-153
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• 2003

고고학적 발굴에 있어 지하정보는 매우 중요한 요소로서 지하정보를 얻기 위한 방법으로서 지구물리학적 탐사방법이 많이 적용되고 있다 본 연구는 경상북도 경주시 감포읍 양북면 대본리 앞 바다에 위치한 문무대왕 수중릉에서 측량을 비롯한 각종 지구물리탐사 및 지질공학적 조사결과에 관한 것으로서 물리탐사방법의 고고학적 조사 발굴분야에의 적용 가능성을 확인하고자 수행하였다 대왕암은 크게 개의 화강암으로 이루어진 바위섬으로 이루어져 있으며 크기는 東西 35.0m, 南北 약 36.0m이며, 높이는 최대 약 5.30m이다. 대왕암 내부의 공동에는 巨石이 하나 있으며, 최대 수심 약 1.5m를 거의 일정하게 유지하며, 물에 잠겨 있다. 거석은 東西 최대 2.47m, 南北, 최대 3.75m, 높이는 최대 약 1.35m의 크리를 갖는 타원체형이며, 무게는 약 20ton이다. 바위섬 내부의 공동은 암반에 자연적으로 발달 형성된 절리 및 틈새를 인위적으로 정 등을 사용하여 이미 어느 정도 있던 공간을 확장한 것으로 판단되며 절리 및 측량결과로 볼 때 거석은 대왕암에 발달한 절리에 의한 암반블록을 다듬은 것으로 판단된다. GPR 탐사결과 거석하부의 암반에는 주변의 대왕암과 같이 절리가 잘 발달하여 있고 인공구조물 혹은 석 함 등을 묻기 위한 공동을 발견할 수 없었다 한편 전자유도 탐사결과도 구조물 특히 철제 유구 등에 의한 반응을 찾을 수 없었다 이상과 같은 관찰 및 조사결과를 토대로 대왕암과 거석은 바위섬의 자연상태를 최대한 유지하면서 인위적으로 조성된 것으로 판단되며, 巨石하부에서 장골흔적을 발견할 수 없었더. 巨石은 뼈를 바다에 뿌린 제단과 같은 구실을 한 것으로 판단된다.

• 해양환경안전학회지
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• 제16권2호
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• pp.175-183
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• 2010

갯벌 패류양식장의 구조물 설치 및 지형적 공간배치에 따른 저서생물 현황을 파악하기 위해 고흥 남성리 양식장의 실제적인 사례를 조사하였다. 그 결과를 요약하면 다음과 같다. (1) 남성리 갯벌양식장의 지반 경사는 약 $1^{\circ}$ 미만으로 매우 평탄하며, 육지로부터 약 150 m까지는 $\sqcup$형, 그 후는 $\sqcap$형 지반형태를 가진다. $\sqcup$형 지반은 간출시 해수를 가두고 $\sqcap$형 지반은 외해 유출을 가로막을 뿐만 아니라 내부인자로서 해수 유출 시간을 지연시키는 작용/영향을 하게 될 것으로 생각된다. (2) 양식장 구분 시설물로 설치된 굴 패각 망태 또는 사석의 축제 형식은 총 5가지로 구분할 수 있으며, 양식장 대기 노출 시간과 침수시간은 각각 181분과 434분이었다. (3) 수치실험결과로서 대상해역의 내습 심해파랑은 최대파고 약 0.5m로서 매우 정온한 해역특성을 가지며, 탁월 입사파향은 나로대교 하단부는 S방향, 갯벌양식장 인근은 SE, SSW, S방향으로 조사되었다. (4) 고흥 남성리 주변 해역의 입도분석결과, 퇴적물은 Gravel 0.0~5.81(평균 1.70)%, 모래 14.15~18.39(평균 13.23)%, 실트 27.59~47.15(평균 30.84)%, 점토 35.79~55.73(평균 36.19)%로 구성되어 있으며, Folk 분류법에 의해 (g)M, sM(Sandy mud), gM(Gravelly mud)로 분류되었다. (5) 2010년 1월 남성리 패류 양식장 저서생물 현황조사에서는 총 11종이 1%이상의 우점종으로 출현하였으며 이 중 연체동물이 1종, 다모류가 8종, 갑각류가 2종이었다.