• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.45-56
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• 2021

In order to understand the tide and current around the sea route of Jinhae and Masan passages, tide measurement and 2D numerical model experiments of tidal current and residual flow were carried out. Tide is composed of 84% of semi-diurnal tide, 11% of diurnal tide and 4% of shallow water tide, respectively. Phase lags of the major components for the tide around the study area have little differences. The flows are reversing on the whole, but have rotational form around Jamdo Island, south of Masan passage in spring tide and Ungdo Island, north of Masan passage in middle and neap tide. Current flows the speed of 50 cm/s in the sea areas near small islands, 5 cm/s in Jinhae harbor, Hangam bay and near Jinhae industrial complex and 20-30 cm/s in Jinhae passage, Budo channel and Masan passage. Tide-induced topographical eddies are formed near small islands, but few eddies exist and the flow rate of less than 5 cm/s tidal residual current formed in Jinhae and Masan passages. The flows in Jinhae and Masan passage give a good condition for a passage into Jinhae and Masan harbor.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.3 no.2
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• pp.84-96
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• 2022

Most of the islands of Korea are distributed in the South and West Sea, and it consists of independent small stream. As a result, the fish community that inhabits the island's stream is isolated from the mainland and other island. This study utilized a Self-Organizing Map (SOM) and a random forest model to analyze the relationship between environmental variables and fish communities inhabiting islands in South Korea. Through the SOM analysis, the fish communities were divided into three clusters, and there were differences in biotic and abiotic factors between these groups. Cluster I consisted of sites with relatively larger island areas and a higher number of species and population. It was found that 15 out of 16 indicator species were included. Meanwhile, the remaining clusters had fewer species and populations. Cluster II, especially, showed the lowest impact from physical variables such as water width and depth. As a result of predicting the species richness using the random forest model, physical variables in habitats, such as stream width and water depth, had a relatively higher importance on species richness. On the other hand, forest area was the most important variables for predicting Shannon diversity, followed by maximum water depth, and gravel. The results suggest that this study can be used as basic data for establishing a stream ecosystem management strategy in terms of conservation and protection of biological resources in streams of islands.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.109-114
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• 2009

Although island is great worth in ecology, environmental conservation and important territory as a national land for developing the marine, the bottom of the sea and also ecological studying field for the ages to come, it has not been managed because of lack of a scientific surveying. In the case of a cadastral record, inaccessible islands have not been registered in current cadastral record because of the limit of surveying technology in 1910. Therefore, a scientific investigation and systematic management about unregistered islands are necessary. But, a airborne laser scanning system is possible to acquire an accurate positions with digital images about inaccessible islands. Therefore, scientific detection of unregistered islands became possible. This paper presented the results of the shoreline extraction around the Heuksan island using Lidar data and the detection of unregistered islands comparing the cadastral map to the ortho-image. Also, we presented the extraction technique of unregistered islands by calculating their positions and areas. As a result, we extracted effectively 16 unregistered islands around the Heuksan island.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.5
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• pp.432-449
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• 2009

In this study, the effects of high-resolution land cover on the simulation of near-surface meteorological fields were evaluated in two different coastal regions using Weather Research and Forecasting (WRF) model. These analyses were performed using the middle classification land cover data upgraded by the Korean Ministry of Environment (KME). For the purpose of this study, two coastal areas were selected as follows: (1) the southwestern coastal (SWC) region characterized by complex shoreline and (2) the eastern coastal (EC) region described a high mountain and a simple coastline. The result showed that the application of high-resolution land cover were found to be notably distinguished between the SWC and EC regions. The land cover improvement has contributed to generate the realistic complex coastline and the distribution of small islands in the SWC region and the expansion of urban and built-up land along the sea front in the EC region, respectively. The model study indicated that the improvement of land cover caused a temperature change on wide areas of inland and nearby sea for the SWC region, and narrow areas along the coastal line for the EC region. These temperature variations in the two regions resulted in a decrease and an increase in land-breeze and sea-breeze intensity, respectively (especially the SWC region). Interestingly, the improvement of land cover can contribute large enough to change wind distributions over the sea in coastal areas.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5_2
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• pp.176-185
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• 2010

This study aimed to clarify meanings of Palkyung(八景) in different regions which can be considered as the prototype of the region's cultural landscape and also to confirm the change process by pointing out landscape characteristics and finally, to provide a foundation for the regions to establish their own identities, so they could be provided against the changes from developments in other areas. The relationship between the characteristics of landscape values and the components of 32 Palkyung in 4 places those are Gogunsan, Wido, Gunsan and Byunsan under Saemankeum area have been analyzed and evaluated from operational point of view to clarify the structure of the landscape concept. Some important differentiation points would be the sunset of the West Sea, sailing boats and the sceneries related to fishing as they are in the West Sea Islands and the coastal regions; and it clearly reflects the local customs and the characteristics of the landscapes. Each of Gogunsan, Wido and Gunsan Palkyung has 2 distance views with 4km of visible area while Byunsan Palkyung has only 1; and it is considered that because it is mountain area. Most of the Byunsan Palkyung has close range views except for Seohaenakjo and there are around 4 close range views in other areas. There were 4 landscape dominated influence areas each in Gunsan and Byunsan, which means that there are comparatively more close to middle range views. Moreover, each region contains 2 to 3 views of psychological influence but as mentioned, Byunsan has only 1 view of psychological influence. Therefore it is very important and valuable thing to consider the scenic relationship, preservation and reconstruction of Palkyung when planning the project.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.6
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• pp.189-203
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• 2023

This study analyzed potential breeding sites for black-faced spoonbills on 70 non-breeding, uninhabited islands in Incheon, Korea, in order to suggest potential breeding sites for black-faced spoonbills, whose breeding population has recently been increasing. By comparing the environmental characteristics of breeding and non-breeding areas identified through a literature search, we developed a discriminant to identify potential breeding areas for black-faced spoonbills. Among a total of eight environmental variables(Island area, distance from land, distance to mudflat, distance to rice field, distance to sea route, depth of water, mudflat area, rice field area), the variables that influenced the selection of breeding sites for black-faced spoonbills were average water depth, tidal flat area, and paddy field area. As a result of discriminant analysis of breeding islands using these variables, the accuracy was found to be quite high at 80%. As a result of applying the developed discriminant to non-breeding islands located in the Incheon region, a total of 9 islands(Yongrando, Goseokdo, Beolyeom, Joreumseom, Goeriseom, Hambakdo, Moido, Bigajido, Ahyeom) were identified as potential breeding grounds for spoonbills. The research results can be used as basic data for future management of black-faced spoonbill breeding sites and selection of alternative habitats.

• Journal of the Korean Institute of Navigation
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• v.18 no.3
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• pp.19-30
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• 1994

By use of the recent tropical cyclones' data in the Northwest Pacific Ocean, the occurrence frequency and region of typhoon as well as the features of the monthly mean track were analyzed. As the result of this study, (1) mean occurrence frequency of typhoon per year is 27.5, and 68% of total typhoons were formed in July to October and shown the highest frequency in August. (2) The ave-rage duration of typhoons is 8.5 days, and super typhoon which maximum sustained surface wind speeds is more than 130 knots occurs most frequently in October and November. (3) The highest frequency ap-pears around the Caroline, Mariana and Marshall Islands, and in wintertime, typhoon occurs in lower lati-tude comparing with those in summertime. (4) The typhoon track depends upon the distribution of pres-sure system and steering current in neighbouring areas. The mean track of typhoon can be classified into three types such as westward-moving type, northward-moving type and abnormally moving type. The west-ward-moving typhoons make landfall on the southern China by way of the South China Sea in June and July, on mid-part of China in August and September, and on Indo-china Peninsula in October and Novem-ber. The northward-moving typhoons approximately move on north~northwestward track to $20~30^{\circ}N$ from the occurrence region, then recurve to the East Sea through Korean Peninsula and Kyushu Island in June and July, to the Noth Pacific Ocean along the Japanese Islands in August and September and to the North Pacific Ocean through the seas far south off the Japan in October and November.

• Ocean and Polar Research
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• v.38 no.4
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• pp.259-270
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• 2016

Sea Surface Salinity (SSS) observations from the Aquarius satellite in the East Sea show large systematic biases mainly caused by the surrounding lands and Radio Frequency Interferences (RFI) along the descending orbits on which the satellite travels from the Asian continent to the East Sea. To develop a technique for correcting the systematic biases unique to the East Sea, the least square regression between in situ observations of salinity and the reanalyzed salinities by HYCOM is first performed. Then monthly mean reanalyzed salinities fitted to the in situ salinities are compared with monthly mean Aquarius salinities to calculate mean biases in $1^{\circ}{\times}1^{\circ}$ boxes. Mean biases in winter (December-March) are found to be considerably larger than those in other seasons possibly caused by the inadequate correction of surface roughness in the sea surrounded by the land, and thus the mean bias corrections are performed using two bias tables. Large negative biases are found in the area near the coast of Japan and in the areas with islands. In the northern East Sea, data sets using the ascending orbit only (SCIA) are chosen for correction because of large RFI errors on the descending orbit (SCID). Resulting mean biases between the reanalysis salinities fitted to in situ observations and the bias corrected Aquarius salinities are less than 0.2 psu in all areas. The corrected mean salinity distributions in March and September demonstrate marked improvements when compared with mean salinities from the World Ocean Atlas (WOA [2005-2012]). In September, salinity distributions based on the corrected Aquarius and on the WOA (2005-2012) show similar distributions of Changjiang Diluted Water (CDW) in the East Sea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.3
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• pp.112-124
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• 2016

In order to see the spatio-temporal distribution patterns of macrobenthic fauna in subtidal areas of Nakdong River estuary, benthic fauna samples were collected seasonally at 8 sites in subtidal areas of Nakdong River estuary from February, 2013 to November, 2015. Sandy sediment facies was found in the southern part of the barrier islands in Nakdong River estuary while muddy sediment facies occupied at sites in offshore areas. The bottom salinity of the study area was measured greater than 30 psu during the study period. The mean species richness and density were estimated as 266 species and $859ind\;m^{-2}$, respectively. Polychaete worms were the most abundant fauna group, and four polychaete species such as Goniada maculata, Sternaspis chinensis, Magelona japonica, and Heteromastus filiformis occurred as dominant species in this study area. Pseudopolydora kempi known as an opportunistic species occurred dominantly only in August, 2013. From the multivariate analyses, the macrobenthic fauna in the subtidal area of the Nakdong River estuary could be divided into 2 assemblages that each occupied sites near barrier islands and offshore areas by sediment facies.

• ALGAE
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• v.21 no.2
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• pp.235-243
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• 2006

Benthic sediment samples ranging from poorly aggregated sand to complex, stratified mats were collected from six hypersaline ponds from March and July 1995 in the British Virgin Islands. Assemblages were analyzed with respect to species composition and abundance within visibly distinct layers in each mat sample. In individual ponds there was no apparent association between changing depth and the development of the benthic mats. Some species were present in all samples (e.g. Oscillatoria sp.) while others were restricted to single sites (e.g. Johannesbaptistia pellucida). Primary species included Microcoleus chthonoplastes, Phormidium spp., Coccochloris stagnina, and purple sulfur bacteria. Quantitative analysis of community structure included cluster and principal component analysis. Samples from individual ponds were often clustered; however, this was subject to seasonal variation. Mats collected in March were generally thicker and contained more layers than those in July. Variation among sites was not explained by the measured variation in environmental factors such as average pond salinity, depth, and oxygen concentration (mg/L). This study provides a detailed analysis of mat communities in hypersaline ponds and compares them with similar mat communities from other areas.