• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.2
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• pp.139-147
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• 2010

This study monitored a variety of marine fish communities in artificial reefs unit of the total 5 types (Dice type, Octagonal turtle type, Two-stage tube type, Gazebo type, Tetrapod type) which are located in the marine ranching at Jeju island by scuba diving in May, July, October and December 2009. Underwater photographing was accomplished at total 3 phases (condition of artificial reefs photographing, concentric circle movement photographing and line transect photographing). The preservation condition of artificial reefs facility was very good, and the dominant species were Chromis notatus, Sebastes thompsoni, Oplegnathus fasciatus and Halichoeres poecilopterus. Fish abundance was high in May and June, and low in October and December, 2009. Chromis notatus was dominant at the all types of artificial reefs, Halichoeres poecilopterus for Gazebo type and Tetrapod type of artificial reefs, and Sebastes thompsoni for Dice type, Octagonal turtle type and Two-stage tube type of artificial reefs.

• Journal of Navigation and Port Research
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• v.35 no.9
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• pp.755-763
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• 2011

Recently, extreme tsunami waves generated by submarine earthquake have caused tremendous damages to the coastal cities and ports. Strong seiche oscillations and runups are observed in specific sea areas around the world. Although no frequent impacts to the coast of Korean peninsula, there exist some important events in the east of Korea in the past. This study focuses on two historical events and recalculate with different fault and rupture mechanism for prediction considering the recent trend of submarine earthquake. The present study of the 1983 Akita tsunamis demonstrates the multi-scale resonance along continental coasts. Together with the Nankai tsunami for inland sea, we have confirmed the inland sea resonance surrounded by islands in defining the impact along the coast. Coherence and wavelet analyses for deducing a predominant period and time frequency are useful in reasoning the inundation. The resonance modes, which are largely independent of the tsunami source, allow identification of at-risk communities and infrastructure for mitigation of tsunami hazards. Furthermore, understanding of the resonance and the predicted runups for the site of power plant and industrial complex in the east coast of Korea would allow better preparation for the future disasters.

• Ocean and Polar Research
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• v.41 no.4
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• pp.251-263
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• 2019

We investigated the mesozooplankton community structure during autumn in the southern Yellow Sea. Mesozooplankton density generally ranged from 352 to 2,954 ind. m^-3 and varied according to different sampling stations. The copepod Paracalanus parvus s.l. and its copepodites dominated in the communities, corresponding to 57.3% in density of the total. Surface and water-column averaged salinity were positively correlated with density of total mesozooplankton, copepods and a few dominant species, and the tunicate Thalia rhomboides was negatively related to chlorophyll-a concentration. The mesozooplankton community of the study area was divided into three groups according to the cluster analysis using species composition and density: one in the northern coastal region, another in the northern offshore region, and the other in the south. The most significant indicator species for each of the groups were Labidocera euchaeta in the northern coastal region, T. rhomboides in the northern offshore region, and Themisto sp. juveniles in the south. This study provides recent data on the characteristics of the mesozooplankton community in the southern Yellow Sea, which may be valuable for gaining a better understanding of changes in the pelagic ecosystem of the Yellow Sea.

• Wind and Structures
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• v.31 no.4
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• pp.335-350
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• 2020

In coastal residential communities, especially along the coastline, flooding is a frequent natural hazard that impacts the area. To reduce the adverse effects of flooding, it is recommended to elevate coastal buildings to a certain safe level. However, post storm damage assessment has revealed severe damages sustained by elevated buildings' components such as roofs, walls, and floors. By elevating a structure and creating air gap underneath the floor, the wind velocity increases and the aerodynamics change. This results in varying wind loading and pressure distribution that are different from their slab on grade counterparts. To fill the current knowledge gap, a large-scale aerodynamic wind testing was conducted at the Wall of Wind experimental facility to evaluate the wind pressure distribution over the surfaces of a low-rise gable roof single-story elevated house. The study considered three different stilt heights. This paper presents the observed changes in local and area averaged peak pressure coefficients for the building surfaces of the studied cases. The aerodynamics of the elevated structures are explained. Comparisons are done with ASCE 7-16 and AS/NZS 1170.2 wind loading standards. For the floor surface, the study suggests a wind pressure zoning and pressure coefficients for each stilt height.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.2
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• pp.28-36
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• 2012

Forests are one of the basic assets nearest our daily lives that provide the foundation of life necessities, culture and even survival. These assets pervade local residents' lives as culture and the necessities of life, and they will be handed down to posterity. Therefore, this study was conducted to carry out a field survey on old trees, plant communities and forests in the southern coastal areas in Korea, where not many surveys were not conducted on the forest cultural assets, further examining a possibility that some of the trees should be designated as law-protected. As for the survey of plants, this study investigated 80 different spots of old trees, plant communities and forests, located in 11 cities and counties in Gyengnam Province and Jeonnam Province adjacent to the southern coast of Korea. To measure the health and actual maintenance conditions of old trees and plant communities objectively, the standard of judgment was established through the brain storming of experts. As a result of the field survey, out of all the old trees and plant communities that are not law-protected, this study selected old trees and plant communities that are in good health and likely to pass the standard of designating law-protected trees according to the Established Rule 574 of the Korea Forest Service Regulation. As for the plant community and old trees likely to be law-protected, this study judged that the torreya forest in Naneum Li, Namhae and old trees in 13 spots, in cluding so-called 'Couple Pine Tree' in Pyeongsa Li, Hadong, have a high possibility of being designated as a law-protected plant community and old trees. As for the species of old trees, there were 3 zelkova serrata trees, 3 celtis sinensis persoon trees, 2 pinus densiflora trees, 1 castanopsis cuspidata tree, 1 salix chaenomeloides tree and 1 machilus thunbergii tree found in the survey areas. Overall, this study judged that those old trees and plant communities require a national systematic maintenance by being designated as law-protected ones, and their values should be handed down to posterity as our forest cultural assets.

• Journal of Ecology and Environment
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• v.42 no.3
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• pp.120-127
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• 2018

Background: Cakile edentula (Bigelow) Hook. is a successful invader that has been propagating globally. In Korea, Cakile edentula was found in 2008 for the first time, in the east coast of Korean peninsula. Based on site surveys conducted thereafter, Cakile edentula has propagated in the east coast from Goseong to Jeongdongjin, Gangneung and in the west coast of city of Hwaseong of Gyeonggi-do Province, and Taeangun County of Chungcheongnam-do Province. Results: Cakile edentula has infiltrated into four different vegetation communities (syntaxa) (Calystegio soldanellaeSalsoletum komarovii Ohba, Miyawakiet Tx.1967; Elymo-caricetum Kobomugi Miyawaki 1967; Carex pumila; and Calystegia soldanella) belonging to phytosociological classes of saltwort (barilla) and coastal glehnia. Cakile edentula competes with dominant species such as the saltwort (barilla) and beach morning glory, causing qualitative changes in species composition. It also affects local ecosystems through its competition with indigenous species, causing destruction of the traditional landscape. Conclusions: However, competition of Cakile edentula with indigenous species and the resulting replacement of such species are limitedly reported. Potential competitors with Cakile edentula have not been found yet. In Northeast Asia, qualitative changes realized in local ecosystems due to invasion of Cakile edentula are significantly noticeable. These necessitate proper controls for this invasive alien species to protect and preserve coastal dune areas.

• 한국해양학회지
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• v.19 no.1
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• pp.68-81
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• 1984

To characterize community structure and distribution of phytoplankton, cluster analyses are performed on quantitative data of phytoplankton collected from the southwestern sea of Korea in early summer, 1980. The cluster analysis shows that the phytoplankton of the study area consists of three distinct characteristic communities, representing different water masses. The species of the first community, predominant in the southwestern coastal were of the main land, are mostly neritic and cold water diatoms. The second community consists of neritic and oceanic diatoms, a few flagellates and an euglenoid. These species are predominant in the vicinity of Jeju Island with warm and high saline waters which seems to be a branch of the Kuroshio Current. The species of the last community, consisting primarily of small-sized dinoflagellates, are predominant in the rest part of the study area with warm and low saline water. Addition, the vertical distributions of phytoplankton and environmental factors show that high concentration of phytoplankton cells, chlorophyll-a and dissolved oxygen are observed near the seasonal pycnocline in the off-coastal area. Fraction of nanoplankton take the above 90% of the total cell concentration in the surface mixed layer of off-coastal area where the seasonal pycnocline develops in summer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.849-855
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• 2016

The community composition and distribution of fish species in the middle of the Yellow Sea were investigated in summer from 2008 to 2014. A total of 72 demersal fish species from 46 families and 17 orders were collected. The most common species were Larimichthys polyactis, Engraulis japonicus, and Chaeturichthys hexane, which accounted for 72.0% of the total number of individuals while Liparis tanakai, Larimichthys polyactis, and Lophius litulon accounted for 67.8% of the total biomass. A cluster analysis based on the Bray-Curtis similarity revealed that the fish community fell into three groups, according to latitude. Principal Component Analysis (PCA) and correlation analysis showed that variation in bottom water temperature could act as an indicator of variation in community structure and abundance of the dominant species. Characteristics of fish communities, such as the number of species, the total number of individuals ($/km^2$), and biomass ($/km^2$), were highly correlated with bottom water temperature and depth.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.103-108
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• 2003

This study examined the coastal sand dune vegetation before and after the construction of an embankment on Anmado Island in order to compare vegetation in relation to the development of islands. A total of 24 species distributed on the sand dunes. 18 species were found to be in common before and after the construction of the embankment, which included Vitex rotundifolia, Imperata cylindrica var. koenigii, Zoysia sinica, etc. The species which were not found in this survey included Rumex japonicus, Setaria viridis, Portulaca oleracea, Artemisia japonica, Poiygonum aviculare, etc, and new species included Arena fatua, Carex boottiana, Lycium chinense, Leonurus sibiricus, Torilis japonica, Solanum carolinense, etc. The washing away of sand brought about the changes in habitat and the increase in naturalized plants, which included Oenothera odorata, Lepidium apetalum, Bidens bipinnata, Erigeron canadensis, Datura stramonium, Xanthium strumarium, Arena fatua, Solanum carolinense etc. In addition, the disturbance to this habitat led to the changes in vegetation. The main plant communities in the surveyed site were classified as Vitex rotundifolia-Imperata cylindrica var. koenigil community, Zoysia sinica-Calystegia soldanella community and Messerschmidia sibirica community. The sand dune vegetation on Anmado Island changed with regard to the community and the composition of species after the construction of the embankment, due to the sand being severely eroded. While Vitex rotundifolia community and Commelina communis community were found before the construction of the embankment, they were replaced by Vitex rotundifolia-Imperata cylindrica var. koenigii community, Zoysia sinica-Calystegia soldanella community and Messerschmidia sibirica community, after the construction of the embankment.

• Journal of The Geomorphological Association of Korea
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• v.24 no.1
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• pp.105-116
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• 2017

This article is written in the viewpoint of landscape ecological geography. The coast of South Chung-chong Province will make new characters of region in the development strategies program. This study is to describe geomorphological landscapes of South Chung-chong Province relating with it's environment based on the coast. Although landforms constitute prominent landscape features as tidal flats and rock cliff do, it is nonetheless the features such as beaches, sanddunes, and coastal plains that have various ramifications for human communities. Tidal flats, beaches and coastal sanddunes are special in that their formation is attributable to the combined action of tidal flows, waves and winds. To some extent, the erosion of sand has been a global phenomenon. Human impact are involved. The influence of globalization and expansion of liberal trade appears in regions variously. Individual regions need to secure its competitiveness in the world market. Regions are not value-neutral abstract conception, but must be informal commercialized characters of region. The coast of South Chung-chong Province has experienced rapid and dramatic changes. In industrial times, the middle of west coast Korea turned into a major reclamation at larger scale. Reclaimed land was based on location of industry and mechanized agriculture. The west coast highway and bridges between island and land contributed to the development of west coast transportation. As information society matured, trend and value are changing. Environment and ecology emphasize and rediscover the value of tidal flats and sanddunes. The west coast region now receives attention as eco-tour and sustainable course.