• 제목/요약/키워드: Coastal activities

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Assessment of Sediment Yield according to Observed Dataset

  • Lee, Sangeun;Kang, Sanghyeok
    • Journal of Environmental Science International
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    • v.25 no.10
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    • pp.1433-1444
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    • 2016
  • South Korea is a maritime nation, surrounded by water on three sides; hence, it is important to preserve in a sustainable manner. Most areas, especially those bordering the East Sea, have been suffering from severe coastal erosion. Information on the sediment yield of a river basin is an important requirement for water resources development and management. In Korea, data on suspended sediment yield are limited owing to a lack of logistic support for systematic sediment sampling activities. This paper presents an integrated approach to estimate the sediment yield for ungauged coastal basins by using a soil erosion model and a sediment delivery rate model in a geographic information system (GIS)-based platform. For applying the sediment yield model, a basin specific parameter was validated on the basis of field data, that, ranging from 0.6 to 1.2 for the 19 gauging stations. The calculated specific sediment yield ranged from 17 to $181t/km^2.yr$ in the various basin sizes of Korea. We obtained reasonable sediment yield values when comparing the measured data trends around the world with those in Korean basins.

A study on the sedimentation in the vicinity of the groins near harbor (항만 인근 해안의 인공 구조물 주변 퇴적 작용 분석)

  • Kim Hye-Jin
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2006.06b
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    • pp.179-183
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    • 2006
  • As there are many human activities in the coastal regions, various facilities and coastal engineering structures for protecting beach have been built. Dredging work, reclamation and harbor construction have caused the topography of sea floor to change rapidly. So sedimentation in the vicinity of the groins has get dull and the serious aspects sometimes turn up. Analyzing the surface sediments with transport vector model is one of the good methods to understand the sedimentation in the vicinity of the groins. I analyzed the transport vector of the surface sediments in the vicinity of the groins at the region where serious beach erosion happens near Pohang harbor.

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Study of Low Back-scattering Area on the SAR Image of Waters off the Southeast Coast of Korea (2000년 7월 한국 동남연안 SAR 영상의 낮은 후방산란 해역에 대한 고찰)

  • Kim, Tae-Rim;Park, Jong-Jip;Kim, Sang-Woo
    • Korean Journal of Remote Sensing
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    • v.26 no.2
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    • pp.109-114
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    • 2010
  • This paper studies the origin of low back-scattering area appeared on the SAR image taken on the coastal waters off the southeast coast of Korea on July 5, 2000. Cold waters were frequently observed during summer on this coastal waters, and quasi-simultaneously taken AVHRR and SeaWiFS images also showed cold surface waters and high concentration of chlorophyll-a, respectively. By synergetic analysis of multi-sensor satellite images, it is strongly suggested that the cold and nutrient rich upwelling waters caused the high phytoplankton density and high biological activities in the water producing natural films for low back-scattering.

An Analysis of Fishermen's Preference for the Type of Fishing Quota System by Fish Species (어업인의 어종별 어획쿼터제도 유형의 선호도 분석)

  • Seong-Hyun Sim
    • The Journal of Fisheries Business Administration
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    • v.54 no.3
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    • pp.17-28
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    • 2023
  • In this study, a conjoint analysis was conducted to derive a combination of fishing quota management system by fish species preferred by fishermen. In the analysis, detailed levels were set according to each attribute of the system. For analysis, this study conducted a design question survey for conjoint analysis on 303 fishermen engaged in fishing activities in the offshore and coastal sea. The Conjoint analysis was conducted on all fishermen, offshore fishermen and coastal fishermen. In addition, an analysis was conducted on TAC system participants and non-TAC system participants, and the targets were classified for comparison according to the characteristics of fishermen. Fishermen's preference for the system confirmed for six attribute ("catching fish even if there is no fishing quota", "how to allocate fishing quota", "fishing quota management agency", "upper limit of fishing quota," "Possibility of Trading in the Fishing Quota", and "Application of Other Regulations.") and the detailed level of each attribute. As a result of the analysis of the importance of attributes, fishermen thought that "fishing quota management agency (24.1%)" was very important, and "catching fish even if there is no fishing quota (23.9%)" and "how to allocate fishing quotas (22.9%)" were also given some importance.

Characteristics of Wintering Habitat use by Black-tailed Gulls (Larus crassirostris) on the West Coast of Korea

  • Tehan Kang;Soon Sik Kim;Daehan Cho;Tae Wan Kim;Woon Kee Paek;Si-Wan Lee
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.5 no.2
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    • pp.37-42
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    • 2024
  • This study used a GPS tracker to determine characteristics of wintering habitat use by black-tailed gulls on the west coast of Korea. Results of this study showed a southward movement in December and a northward movement in March. The wintering habitat was confirmed to include the southwest coastal island area (Group 1), the inland coastal area (Group 2), and China (Group 3). The wintering home range was the narrowest in October and the widest in December. Home range of Group 1 was increased from November, showing the maximum in December, decreased in February, and then tended to increase again in March. Group 2 showed the widest home range in November and a narrow range of home range from December. Home range of Group 3 showed a mixed pattern of group 1 and group 2. The flight rate was the lowest in January and the highest in March. Day and night flight rates showed significant differences by month. This study identified wintering characteristics of the West Coast population of black-tailed gulls on the West Coast, including their wintering areas, migration periods, and use patterns. These wintering characteristics of black-tailed gull in the west coast area are thought to be affected by environmental factors (such as food resources and fishing activities) and geographical characteristics of the West Coast where many islands are distributed.

A study on Marine Protected Areas as Fisheries Management Tools (어업자원 관리수단으로서의 해양보호구역제도에 관한 연구)

  • Chae, Dong-Ryul;Nam, Su-Min
    • The Journal of Fisheries Business Administration
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    • v.42 no.3
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    • pp.41-61
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    • 2011
  • Marine protected Areas(MPAs) are specially designated zones of the sea that are designed to secure operation of ecosystem function and to restore marine ecosystem to the original state by excluding all detrimental human activities. MPAs have been proposed in many countries as means of realizing sustainable fisheries and recently MPAs are newly receiving attention as precautionary measure for global warming and climate change. The purpose of this paper is to examine the possibility of MPAs as fisheries management tools through a wide range of literature analysis and to suggest necessity of fisheries purpose of MPAs in Korea. Establishment of marine protected area can accompany various economic benefits such as restoration of marine environment, preservation of habitats, promotion of marine tourism and so on. Especially, a lot of case studies suggested that MPAs may bring out benefits to the fishing industry as a result of enhanced stocks. Fisheries benefits of MPAs on targeted species include increased abundance, increased mean individual size and age, increased reproductive output, enhanced recruitment inside and outside refuge, maintenance of genetic diversity of stocks, and enhanced fishery yields in adjacent fishing grounds, so called spill-over. MPAs for ecosystem conservation and protection of coastal wetland have been applied appropriately and effectively, however, the Korean MPAs system is still detective due to absence of fisheries purpose MPAs. Finally, suggestions for Korean MPAs can be summarized as following four recommendations; to establish number of small-scale MPAs rather than few large MPAs, to designate island and its surrounding areas as reserve, to consider MPA design with stock enhancement program, and to undertake co-management with Eochon-Gye, the traditional coastal community in Korea.

Application of stoichiometric method in the assessment of groundwater chemistry in a coastal region having complex contaminant sources

  • Rajmohan Natarajan;Kim, Kang-Joo;Hwang, Gab-Soo;Kim, Hyun-Jung;Cho, Min-Joe
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.499-502
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    • 2004
  • Groundwater chemistry in a coastal region having complex contaminant sources was investigated. Water analysis data for 197 groundwater samples collected from the uniformly distributed sixty-six wells were used. Chemical analysis rand results indicate that groundwaters show wide concentration ranges in major inorganic ions, reflecting complex hydrochemical processes of pollutants. Due to the complexity of groundwater chemistry, Results illustrate that thirty five percent of the wells do not fit for drinking based on nitrate and chloride concentration in the study area. the samples were classified into four groups based on Cl and NO$_3$ concentrations and the processes controlling water chemistry were evaluated based on the reaction stoichiometry. The results explained the importance of mineral weathering, anthropogenic activities (nitrification and oxidation of organic matters), and Cl-salt inputs (seawater, deicer, NaCl, etc.) on groundwater chemistry. It was revealed that mineral dissolution is the major process controlling the water chemistry of the low Cl and NO$_3$ group (Group 1). Groundwaters high in NO$_3$ (Groups 2 and 4) are acidic in nature, and their chemistry is largely influenced by nitrification, oxidation of organic matters and mineral dissolution. In the case of chloride rich waters (Group 3), groundwater chemistry is highly influenced by mineral weathering and seawater intrusion associated with cation-exchange reactions.

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Characteristics of Surface Backscattering Signal in the Coastal Bay (내만에서의 해수면 후방산란신호 특성)

  • 최지웅;나정열;조운현
    • The Journal of the Acoustical Society of Korea
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    • v.19 no.2
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    • pp.46-53
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    • 2000
  • In coastal bay waters, bubbles are generated by relatively heavy ship-traffic, breaking waves due to man-made structures and biological activities. Therefore, the bubble-generating mechanism as well as the bubble density distribution in the bay are quite different from the open ocean where breaking waves are major contributor for bubble density distribution. High frequency surface-backscattered signals were obtained in the coastal bay waters and they were analyzed to compare with those from the open waters in terms of the sea-surface backscattering strength at various grazing angles, the reverberation characteristics in the sub-surface layer and spectral spreading of the scattered signals. The results show that, the surface scattered signals have an irregular distribution of amplitude in time and the width of the spectral spreading is wider than that of the open sea with rough surface. Furthermore, the amplitude distribution of the reverberation signals is not following the Rayleigh distribution, that is eon to be a typical pattern for the open ocean. The results of our analysis imply that the bubble size and the bubble density in the bay are quite different from those observed in the open waters.

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Light Pollution of Outdoor Lighting in Coastal Area - Focused on Busan City - (해안가 야간경관조명의 빛공해 평가 - 부산시를 중심으로 -)

  • Kong, Hyo-Joo;Kim, Jeong-Tai
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.6
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    • pp.18-26
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    • 2010
  • Outdoor lighting has become a necessary essential part of society for safety and comfortable space. However, inappropriate outdoor lighting leads to energy waste and poor landscape. Outdoor lighting is a very important social element, which enables us to conduct various activities at night in a safe, efficient and comfort way. River Thames in UK, Venice in Italy and Sydney in Australia is a good example of the coastal area. This paper aims to evaluate the light pollution of outdoor lighting in coastal area in Busan city. The Radiant Imaging ProMetric-1400 was used to measure the luminance of Gwangalli Beach, Marine City and Haeundae Beach. Compare to the CIE recommendation level the luminance of the all outdoor lighting were about 2~20 times higher. Outdoor lighting of the building facade luminance level and color should be particularly limited.

Analysis on the Navigational Dangerous Elements in Southwestern Coastal Area of Korea (서남해 연안해역의 항행 위해요소에 관한 분석)

  • Baek, Won-Sun;Gim, Ok-Sok;Jeong, Jae-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.3
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    • pp.219-225
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    • 2008
  • Since July 2006, marine traffic safety management system have been enforced to support the vessels transiting across the coastal area and the vessels coming in and out of ports in southwestern coastal area where heavy traffic density and marine casualties occurred frequently. The marine traffic volume for the marine traffic environmental assessment was measured by the information from RADAR and AIS system in the area. The distributions of marine casualties were analyzed in the main routes and traffic separation schemes during the last five years and the navigational dangerous elements were investigated with the influence of natural environment, the distribution of fisheries and survey questionnaire. Marine accidents of merchant ships have a tendency to decrease gradually but in case of fishing boats, the rate of marine accidents have a contrary results in this area during the last five years. The dangerous elements on navigation appeared to be the dense force from June to August, fisheries activities and the vessels which not follow the compulsory watch on VHF-band radio communication equipments.

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