• Title/Summary/Keyword: change of coastal area

Search Result 484, Processing Time 0.032 seconds

Improving the Designation Criteria of Coastal and Marine Protected Areas through the Application of AHP (AHP를 이용한 연안.해양보호구역 지정기준 개선 연구)

  • Nam, Jung-Ho;Yook, Keun-Hyung
    • Journal of Environmental Policy
    • /
    • v.6 no.3
    • /
    • pp.57-89
    • /
    • 2007
  • The Korean government has put mamy efforts into the protection of ecological values of coastal and marine ecosystems since the mid 1990s, recognizing ecological values and economic contributions of coastal and marine ecosystems. Rapid increase of coastal and marine protected areas in terms of number and size implies the innovative change of national policy regarding ecosystem protection. As of the end of 2006, the total number and size of the protected areas account for 425 and $10,666.8km^2$ respectively. Despite of this achievement, the current policy regime on the protected areas has not been quite successful dealing with in managerial issues. The ambiguity and the lacking objectivity of designation criteria have, been causes of pending issues such as conflict outbreaks, 'paper parks', duplicated designation, etc. This paper aims at improving current designation criteria based on AHP(Analytic Hierarchy Process). The suggestion of the study covers both the new designation criteria and the weighing factor on each criterion considering different ecological and socio-economic characteristics of 'wetland protected area' and 'marine protected area'.

  • PDF

Long-Term Analysis of Tropical Cyclones in the Southwest Pacific and Influences on Tuvalu from 2000 to 2021

  • Sree Juwel Kumar Chowdhury;Chan-Su Yang
    • Korean Journal of Remote Sensing
    • /
    • v.39 no.4
    • /
    • pp.441-458
    • /
    • 2023
  • Tropical cyclones frequently occur in the Southwest Pacific Ocean and are considered one of the driving forces for coastal alterations. Therefore, this study investigates the frequency and intensity of tropical cyclonesfrom 2000 to 2021 and their influence on the surface winds and wave conditions around the atoll nation Tuvalu. Cyclone best-track and ERA5 single-level reanalysis data are utilized to analyze the condition of the surface winds, significant wave heights, mean wave direction, and mean wave period. Additionally, the scatterometer-derived wind information was employed to compare wind conditions with the ERA5 data. On average, nine cyclones per year originated here, and the frequency increased to 11 cyclones during the last three years while the intensity decreased by 25 m/s (maximum sustained wind speed). Besides, a total of 14 cyclones were observed around Tuvalu during the period from 2015 to 2021, which showed an increase of 3 cyclones compared to the preceding period of 2001 to 2007. During cyclones, the significant wave height reached the highest 4.8 m near Tuvalu, and the waves propagated in the east-southeast direction during most of the cyclone events (52%). In addition, prolonged swells with a mean wave period of 7 to 11 seconds were generated in the vicinity of Tuvalu, for which coastal alteration can occur. After this preliminary analysis, it was found that the waves generated by cyclones have a crucial impact in altering the coastal area of Tuvalu. In the future, remotely sensed high-resolution satellite data with this wave information will be used to find out the degree of alterations that happened in the coastal area of Tuvalu before and after the cyclone events.

Report on the Field Excursion, 'Tsunami impact on the coastal zone of Thailand' ('태국 연안역의 지진해일 충격' 야외답사 보고)

  • CHANG SE WON;LEE HEE-IL;PARK YOUNG SOO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.10 no.3
    • /
    • pp.171-180
    • /
    • 2005
  • Related to the tsunami impact caused by the 2004 Sumatra earthquake, field excursion of the title 'Tsunami impact on the coastal zone of Thailand' was carried out along the damaged coasts of Thailand fur three days. The damaged coastal zones along the Andaman Sea coasts of Thailand are classified into the severely damaged, the moderately damaged, and the slightly damaged coastal zone by the degree of damage. Channels of the river- mouths were widen, and the beach sands were eroded, transported, and then redeposited in the near shore or in the back beach area. Field excursion stops were 12 in the representative areas like Phang Nga province, the severely damaged coastal zone and Phuket Island, the slightly damaged coastal zone. In this report, the geo-logical effects on the coastal zone of Thailand by tsunami will be mainly illustrated by the satellite data before and after tsunami and the photographs taken during the field excursion.

Effect of Environmental Variables on Changes in Macrobenthic Communities in the Coastal Area of Inchon, Korea (인천연안 대형저서동물 군집 변동에 미치는 환경요인의 영향)

  • YU Ok Hwan;KOH Byoung-Seol;LEE Hyung-Gon;LEE Jae-Hac
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.37 no.5
    • /
    • pp.423-432
    • /
    • 2004
  • In coastal area of Inchon, dredging and the disposal of dredged material for sea-wall construction and reclamation have increased in recent years. These activities may impact the benthic environment and result in changes in benthic communities, but little information is available on the extent and direction of these changes. We investigated whether there have been changes in the dominant macrobenthic species and benthic community over the last decade, and explored the relationship between environmental variables and spatial patterns of macrobenthic community structure. We sampled macrobenthos and recorded environmental variables in the coastal habitats of Inchon in March and June 2004. In total, 212 macrobenthic species were recorded during this study, predominately crustaceans $(34{\%})$, mollusks $(32{\%})$ and polychaetes $(21{\%})$. The mean density of macrobenthos was $1,393\;ind./m^{2}$.The most abundant species was Amphioplus japonicus $(20.5{\%})$, followed by Heteromastus filiformis $(14.4{\%})$, Theora fragilis $(8.2{\%})$ and Ampharete sp. $(4.0{\%})$. Over the past decade the dominant macrobenthic species in this area shifted. Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among three regions: the middle part of the sampling area (B), site 8 (C) and other sites (A). Mean density varied significantly among the three regions, but no differences in the number of species and diversity (H') were observed. The distribution of the macrobenthic community was affected by environmental variables such as percentage sand content and sediment kurtosis. Species that were important in different areas included A. japonicus in region A, Raeta puchella in region B and T. fragilis in region C. The important species in regions B and C were filter-feeding bivalves, and the abundance of these species may be related to the increase in percentage sand content. We suggest that the sediment composition (percentage sand content) may be an important factor in determining the dominant species and structure of the macrobenthic communities in coastal Inchon. Long-term monitoring programs are necessary to understand ongoing changes in the benthic communities of this area.

Mitigation for the anti-function in caused by Saemangeum reclamation (새만금간척에 따른 미티게이션)

  • 신문섭
    • Proceedings of the Korean Society of Agricultural Engineers Conference
    • /
    • 1999.10c
    • /
    • pp.169-174
    • /
    • 1999
  • The reclamation area of Saemangeum (Kunsan) located between 126$^{\circ}$10' -126$^{\circ}$50'E and and 35$^{\circ}$35'N -36$^{\circ}$05'N at the western coast of Korea. The construction of the 33km sea dike is building in the Saemangeum area. When the construction of the sea dike in the coastal region takes plase, there exists a certain amount of soil which is diffused by the tidal current. Behavior of the soil diffusion usually depends on its intrinsic characteristics, bathymetry, construction method and used mchinery. The amount of soil at the construction acts as a pollutant which is the cause of changing the marine environment. When the soil material is diffused , it may form a layer which obstructs the light passing into the sea and causes the extinction or alteration of the living beings on the sea bottom. The settlement of soil material could change the sea bottom deposit. The purpose of MITIGATION is to harmonize the development and the conservation of environment, to restrict environmental destruction and to reproduce the enviroment damaged by the construction in the coastal region. The purpose of this study is to find the method by which we minimize the anti-function of development in the coastal region. Tide and tidal current are calculated using a two-dimensional numerical model before the construction of sea dike in Saemangeum Bay. The numerical results are compared well with field observations. On the basis of these results, we caculated the tide and tidal current after the construction of the sea dike in order to investigate the change of the tide and tidal current after the construction of the sea dike. Moreover, we calculated the tide and tidal current after the construction of submerged breakwater in order to preserve the enviornmental condition of creature habitat . We compared the tide and tidal current before and after the construction of submerbed breakwater, to investigate the possbility of MITIGATION in the fisheries.

  • PDF

A Prediction on the Wetlands Change of Suncheon Bay by the Sea Level Rise (해수면 상승에 따른 순천만 습지 변화 예측)

  • MOON, Bora;KIM, Dong-Myung;LEE, Suk-Mo
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.29 no.3
    • /
    • pp.627-635
    • /
    • 2017
  • Sea level rise caused by climate change has become a global issue. Sea level rise seems to be an important factor of the research for coastal areas as it affects topography and vegetation of coasts and especially for the plan of coastal wetlands restoration which needs to be carried out for a long term, it has to be considered sufficiently. The coastal wetlands in Korea was damaged by the land reclamation project but recent concerns on the restoration have increased as its value is evaluated highly. Suncheon Bay had also reclaimed from wetlands to rice field once however this site is very active for restoration nowadays. This study estimated an effect according to sea level rise by 2100, reappearing the none dike condition of Suncheon Bay so that it can be taken account of a future plan of wetland restoration. The Sea Level Affecting Marshes Model(SLAMM) was selected as predicting model. The input data such as DEM(Digital Elevation Model), slope, wetlands category, sea level rise senario, tidal range and accretion rate was applied for the simulation. The results showed a decrease in tidal flat, an increase in sea area and a change of the rice field to transitional salt marsh consistently by 2100. These results of this study could be used as baseline data in the future plan of ecological restoration in Suncheon Bay.

Investigation and Analysis of Shoreline Change using DGPS - Focusing on the Gangnung City Shore in Gangwondo - (DGPS를 이용한 해안선 변화 조사 및 분석 - 강원도 강릉시 연안을 중심으로 -)

  • Lee, Hyung-Seok;Kim, In-Ho
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.10 no.2
    • /
    • pp.1-10
    • /
    • 2007
  • The tendency of erosion and accretion of the coast has occurred by the wanton development of a shore so that establishing the plans of nature preservation and development according to shoreline change is in demand. In this study, six DGPS positioning are executed in the periodic interval of about 2 months to choose coastal area of Gangnung, Gangwon-do and the observation data which is post-processed about 50cm accuracies on the Gangnung regular service is compared with digital map in 1998 and digital chart in 2006. Comparing DGPS values with shoreline of digital map, we know that erosion has occurred locally around training dike placed in Gangmun harbor and in southern Namhangjin, many accretions has happened near the breakwater of Namhangjin region and partial accretion is occurring in the other area. Therefore DGPS which is an acquisition method suitable for GIS data input is in use to collect the horizontal data and it could be used effectively to measure the shoreline change of time series through the long-term continuous observation by the coastal development.

  • PDF

A Study on the Setting Criteria and Management Area for the National Ecological Network (광역생태축 구축을 위한 기준 및 관리지역 설정 연구)

  • Jeon, Seong-Woo;Chun, Joung-Yoon;Seong, Hyeon-Chan;Song, Won-Kyong;Park, Ji-Hee
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.13 no.5
    • /
    • pp.154-171
    • /
    • 2010
  • This study was performed to show criteria of a National Ecological Network (NEN) for South Korea and it was a part of a study of ecological network for broad areas on national land showed by Ministry of Environment of Korea. After 1970s, many european countries presented methods and criteria not on individual protected area but on networking among many habitats. The PEEN (Pan European Ecological Network) and NATURA 2000 are results of those. In South Korea, concepts and mapping metheods of ecological network was studied but those were not applied to the whole national land because the equality and local specialities were not reflected. So, in this study, we presented the criteria composed of forest, river, wildlife and coastal evaluation items in conservation ecology and showed the mapping method which can applied to the national land. After the evaluation on land area which composed of forest, river and wildlife axis. Core areas were $30,616km^2$, buffer zone were $21,870km^2$ and each accounted for 31% and 22% of the national land. Except for Taebaeck-Gangwon region, whole region's core areas were accounted for 20~30% of it and buffer zone were accounted for 20~25% of it, so these can be applied to the national land with equality and local specialities. Forest axis and river axis were clearly linear and connected, but the wildlife axis was dispersed in point form. Therefore, to apply the NEN, a detailed habitat map is important and the interconnected implementation of forest, river, wildlife, and coastal axis is required.

Shoreline Change Before and After Breakwater Extension at the Gungchon Port, Geundeok-myeon, Samcheok-si, Gangwon-do (강원도 삼척시 근덕면 궁촌항 방파제 확장 전, 후의 해안선 변화)

  • Kim, Young-Jae;Hwang, Sangill;Yoon, Soon-Ock
    • Journal of The Geomorphological Association of Korea
    • /
    • v.26 no.2
    • /
    • pp.29-38
    • /
    • 2019
  • This study tries to reveal influence of artificial structure construction on shoreline change using DSAS 4.3. Before breakwater extension at the Gungchon Port, beaches at the study area were dominated by long-term erosion and especially, severe shoreline retreat was prevailed at the Wonpyeong Beach that is opened to offshore. During 2 years after the extension leading formation of shadow zone, the Gungchon Beach was rapidly developed due to sand supply to the shadow zone and then stabilized. The shadow zone only affected the northern part of the Wonpyeong Beach, while beaches from the southern part of the Wonpyeong Beach to the Munam Beach was little affected. Beach nourishment and groin construction led beach development at the northern part of the Wonpyeong Beach, while beach erosion from the southern part of the Wonypeong Beach to the Munam Beach was caused by the groin. This study suggests that sufficient consideration before coastal structure construction should be made regardless of purposes.

Interannual Variabilities of Sea Surface Temperature and Sea Level Anomaly related to ENSO in the Tropical and North Pacific Ocean System (열대 및 북태평양에서 ENSO와 관련된 표층수온과 해면고도의 경년 변동성)

  • Kim, Eung;Jeon, Dong-Chull
    • Ocean and Polar Research
    • /
    • v.30 no.3
    • /
    • pp.313-324
    • /
    • 2008
  • In order to understand the variation of ENSO-related oceanic environments in the tropical and North Pacific Ocean, spatio-temporal variations of sea surface temperature anomaly (SSTA) and sea surface height anomaly (SSHA) are analyzed from distributions of complex empirical orthogonal functions (CEOF). Correlations among warm pool variation, southern oscillation index, and ocean surface currents were also examined with respect to interannual variability of the warm pool in western tropical Pacific. Spatio-temporal distributions of the first CEOF modes for SSTA and SSHA indicate that their variabilities are associated with ENSO events, which have a variance over 30% in the North Pacific. The primary reasons for their variabilities are different; SST is predominantly influenced by the change of barrier layer thickness, while SSH fluctuates with the same phase as propagation of an ENSO episode in the zonal direction. Horizontal boundary of warm pool area, which normally centered around $149^{\circ}E$ in the tropics, seemed to be expanded to the middle and eastern tropical regions by strong zonal currents through the mature phase of an ENSO episode.