• Title/Summary/Keyword: Coastal Zone.

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New Approach for Surf Zone Dynamics (쇄파대 동력학에 대한 새로운 접근)

  • Lee, Jung-Lyul;Hsiang Wang
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.5 no.4
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    • pp.384-394
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    • 1993
  • A simple surf zone model is presented The present model takes a quite different approach by showing that wave action is conserved in the surf zone. This condition together with the conservation of energy enables us to develop a surf zone model that requires fewer empirical coefficients. The model is capable of predicting surf zone properties and is presented in analytical forms for the two-dimensional gradually-sloped bottoms. The analytical results were compared favorably with available laboratory data. This surf zone model provides the surface current pattern of the vertical circulation model. and consequently, significantly contributes to solving the three-dimensional current pattern.

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Error Bounds Analysis of the Environmental Data in Lake Shihwa and Incheon Coastal Zone (시화호.인천연안 환경자료의 오차범위 분석)

  • Cho, Hong-Yeon
    • Ocean and Polar Research
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    • v.30 no.2
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    • pp.149-158
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    • 2008
  • The characteristic analysis of the estimated population parameters, i.e., standard deviation and error bound of coastal pollutant concentrations (hereafter PC, i.e., COD, TN, and TP concentrations), was carried out by using environmental data with different sampling frequency in Lake Shihwa and Incheon coastal zone. The results clearly show that standard deviation of the PC increases as its mean value increases. The error bounds of the annual mean values based on seasonally measured DO concentrations and PC data in Incheon coastal zone were estimated as ranges 2.26 mg/l, $0.68{\sim}0.86\;mg/l$, $0.62{\sim}0.80\;mg/l$, and $0.074{\sim}0.082\;mg/l$, respectively. In terms of annual mean of the DO concentration and PC in Lake Shihwa, the error bounds based on monthly measured data from 1997 to 2003 were also estimated as ranges 4.0 mg/l, 3.0 mg/l, $0.5{\sim}1.0\;mg/l$, and 0.05 mg/l, respectively. The error bound on the basis of real-time monitoring data is $7{\sim}13%$ only as compared to that of monthly measured data.

COD Pollutants Load Estimation Schemes in Lake Shihwa and Incheon Coastal Zone (시화호 및 인천연안의 COD 오염부하량 추정기법)

  • Cho Hong-Yeon;Cho Bum-Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.18 no.3
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    • pp.262-267
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    • 2006
  • For the concentration management in COD parameters, it requires the measurement and estimation of the COD pollutants load (hereinafter PL) in the watershed. The estimation method of the PL, however, is provided only based on the BOD parameters. The development of COD PL estimation schemes is expected to execute total PL management in coastal zone and needs to more observation and much time. This study provides COD PL estimation schemes using statistical information about ratio analysis with COD & BOD concentration of rivers and drainages of an industrial complex in Lake Shiwha and Incheon Coastal Zone watershed. The COD PL is computed with ease by multiplying the conversion factor, which is calculated as the sum of the average and 1 to 3 (safety factors) times standard deviation. The conversion factor of Lake Shihwa and Incheon Coastal Zone is estimated as 1.7, 2.3 and 2.9 with respect to the safety factor 1, 2, and 3, respectively.

Relationship between the spatial distribution of coastal sand dune plants and edaphic factors in a coastal sand dune system in Korea

  • Hwang, Jeong-sook;Choi, Deok-gyun;Choi, Sung-chul;Park, Han-san;Park, Yong-mok;Bae, Jeong-jin;Choo, Yeon-sik
    • Journal of Ecology and Environment
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    • v.39 no.1
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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.

Climatological Boundary and Characteristics of Coastal Zone over the Southwestern Korean peninsula (한반도 남서해안의 기후학적 연안지대의 경계와 특징)

  • 이영선;하경자;전은희
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.9 no.3
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    • pp.137-152
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    • 2004
  • The climatological characteristics of coastal zone over the southwestern coast of Korea peninsula were investigated using the data observed by AWS (automatic weather system) and 4 buoy points. Coastal zone is climatologically defined as the region bounded by the distinct contrast of temperature gradient and wind speed across coastline. In the southwest of peninsula four cross-lines consisted of AWS aligned with each buoy were selected as Geojedo buoy line, Geomundo buoy line, Chilbaldo buoy line and Dukjukdo buoy line. Analysis on the diurnal cycle and intra-month variation, monthly mean and maximum value, the temperature gradient with distance between buoy and each station and the accumulative frequency of wind speed were applied to find out the characteristics and the range of coast zone. The maximum ranges of coastal zone vary from offshore to Sanglim (about 34 km distance from coastline) for Geojedo buoy line, to Sunchun (about 52 km) for Geo-mundo buoy line, to Jaeundo (about 27 km) for chilbaldo buoy line and to Yongin (about 65 km) for Dukjukdo buoy line. The modification of coastal zone according to synoptic flow was investigated for the onshore, off-shore and calm cases. The ranges of coastal zone are significantly changed with the distance between 65∼90 km for the case of onshore. In addition, we tried to find out the variation of the wind and temperature and the wind ratio of wind speed at ocean to land stations along Geojedo buoy line during 12∼13 Sep. 2003 affected by typhoon (MAEMI).

A Status of Distributions and its Characteristics of the Geomorphological and Geological Landform Resources in Taeanhaean National Park (태안해안국립공원 해안지형과 지질 자원의 분포 현황과 특성)

  • Seo, Jong Cheol
    • Journal of The Geomorphological Association of Korea
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    • v.26 no.4
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    • pp.97-106
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    • 2019
  • This study aims to investigate geomorphological and geological landscapes in the Taeanhaean National Park to ensure they are well-preserved. This study discovered 390 geomorphological and geological landform resources distributed in the coastal zone of Taeanhaean National Park. Representative geomorphological and geological landforms include : sea cliffs, sea caves, wave-cut platforms, sea-stacks, pebble beaches, sand beaches, tidal flats, coastal dunes, coastal dune wetlands and folds (or micro folds) landforms. Deposition landforms are developed more and erosion and weathering landforms are less on the land zone than island zone. These landform resources vary from district to district and can be developed for geo-tourism resources. Combined efforts from the Taeanhaean National Park authorities and residents are essential to manage ecological programs using geomorphological and geological resources.

Bioecological Study of the Northern Coastal Area in Cheju Island - Distribution and Community Structure of Benthic Molluscan Shells - (제주도 북부연안역의 생물생태학적 기초연구 - 저서패류의 분포와 군집구조-)

  • 이정재
    • The Korean Journal of Malacology
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    • v.6 no.1
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    • pp.33-44
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    • 1990
  • A study on the distribution and community structure of benthic molluscan shells of the northern coastal area in Cheju Island was carried out from July 1989 to June 1990. The benthic molluscan shells collected and identified were composed of 3 classes, 9 orders, 29 familes and 81 species. The first dominant species of the wpper intertidal zone of the northern coastal area in Cheju Island was Nodilittorina exigua and second dominant species were Heminerita japonica, Monodenta neritoides, Monodota neritoides, Littorina brevicula, those of middle intertidal zone were Lunella coronata coreensis, Monodonta neritoides and Omphalius rusticus. H. japonica, M. neritoides, O. rusticus, L. coronata coreensis and Niotha livescens were dominant in the lower intertidal zone, and Astralium haematragum was dominant in the infralittoral zone of within 60 feet sea water depth. The benthic molluscan standing biomass of intertidal and infralittoral zones were 145.71-705.55 gr/ /m sup 2 / and 84.57-1645.67 gr/m sup 2/ respectively, But thao among area and zones were apparently differences.

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Application of Tidal Computations for Mokpo Coastal Zone (목포해역에서의 조석모형 적용)

  • Oh, N.S.;Kang, J.H.
    • Journal of Korean Port Research
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    • v.12 no.1
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    • pp.105-111
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    • 1998
  • A horizontal 2-D model which includes the wetting-drying treatment technique in the intertidal zone is applied for the prediction of tidal changes. The flow model is applied to Mokpo coastal zone and verified by measurement data. Comparing computation results with observed values for the M2 tidal constituent, agreeable correspondence is detected. The validity of the model is also proven by applying it to such areas which have narrow width and rapid velocity, irregular topography and complex geometry. Thus, this model can be used as the compatible prediction model for the tidal change and pollutant transport due to the development of Mokpo coastal zone.

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Numerical Modeling of Ebb-Dominant Tidal Flow in the Mokpo Coastal Zone (목포해역 낙조류 우세현상의 수치모의)

  • Jung, Tae-Sung;Choi, Jong-Hwa
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.22 no.5
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    • pp.333-343
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    • 2010
  • In Mokpo coastal zone, the characteristics showing ebb-dominant tidal flow was confirmed by analysis of observed tide and tidal currents, Physical factors occurring ebb-dominant flow were reviewed. Influence of critical depth for drying, bottom shear stress, coastal reclamation, tidal amplitude, nonlinear tide, and eddy viscosity on the change of ebb-dominant flow was investigated by applying a two-dimensional circulation model. The simulation results for a variety of conditions showed that eddy viscosity and critical depth for drying does little or no impact on the generation of asymmetric flow. Strong bottom friction stress makes ebb-dominant flow clearly. Change of tidal flat into land swells ebb- dominant flow, and change of tidal flat into sea disappears ebb-dominant flow. Nonlinear tides play a decisive role in the generation of asymmetrical tidal flow. Non-linear tides should be included in the open boundary conditions of hydrodynamic modeling in the Mokpo coastal zone.