• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.5
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• pp.57-67
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• 2019

Water-Birds are the birds that occupy the highest proportion in Korea, inland wetlands and reservoirs provide them with a good environment as habitat, but their habitats have been losing because of thoughtless development. Therefore, artificial plant islands in reservoirs are important for improving habitat environment and providing food resources. However, there are no research and standards on the built and management of artificial plant islands. So this study is to find out the density of bird using artificial plant island as habitat through monitoring using UAV focus on the Cheonho-reservoirs located in Seobuk-gu, Cheonan-si(Middle Chungcheong Province). Further, the correlation analysis with environmental factors was conducted to determine the effect of artificial plant islands as habitats for water-birds. The supervised classification of the three-time images taken by the drone identified 244 white-billed ducks and 46 mandarin ducks. The utilization rate was different for each photographed date, and more individuals were identified in wet artificial plant islands than dry ones. As a result of analyzing the utilization follow environmental factors, the distance from the trail showed a significant correlation, and the other factors did not have a statistically significant effect. This study is the first case of the UAV monitoring method of the water-birds using artificial plant islands in the reservoir, and can be used as the basic data for the built and management.

• Proceedings of the Korean Geotechical Society Conference
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• 1992.10a
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• pp.95-106
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• 1992

The paper presents general engineering properties of soft marine sediments and related geotechnical problems associated with construction of artificial islands. Both of the data from foreing and domestic sources are utilized. The selection of soil improvement methods are also discussed.

• Proceedings of the Korean Geotechical Society Conference
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• 1992.10a
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• pp.11-26
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• 1992

An attempt has been made to summarize some of the unique geotechnical problems encountered during construction of a few large man-made islands recently completed off the coast of Osaka Bay, Japan. Large settlements appear to be the most serious problem both during and after construction. Settlements due to consolidation of a thick layer of soft alluvial clay that constitutes seabed seem to virtually cease within a relatively short period of time when vertical drains are installed adequately prior to fill placement. Settlements due to compression of underlying thick diluvial deposits consisting of layers of stiff clays interbedded with coarse-grained soils, however, continue over a prolonged period of time and call for special provisions for structures built on the artificial islands to cope with relatively large future settlements. Although accurate settlement prediction is not possible, it is both technically and economically feasible, nevertheless, to construct large-scale islands. Partjcularly attractive and promising is creation of sizable new areas for various purposes, immediately adjacent to highly-developed, densely-populated cities situated along the coast such as those around Osaka Bay.

• Ocean and Polar Research
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• v.36 no.4
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• pp.353-365
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• 2014

Artificial islands, installations and structures have been used as a major means for ocean development and management since the early 20th century. The International legal regime to regulate the man-made offshore structures also have evolved and the UN Convention on the Law of the Sea (UNCLOS) acts as a basic international instrument for that purpose. Although the Convention includes more detailed provisions on man-made offshore structures, there are some legal issues regarding jurisdiction of coastal State on the man-made offshore structures in the Exclusive Economic Zone (EEZ) or on the Continental shelf. For this reason, this article begins by reviewing the 1958 Convention on the Continental shelf and the UNCLOS by focusing on the EEZ and the Continental shelf regime governing the man-made offshore structures. It next examines some controversial international legal issues that have emerged from the regulation of man-made offshore structures in the EEZ or on the Continental shelf. This is followed by a review of the Korean domestic laws regulating artificial islands, installations and structures in the EEZ or on the continental shelf. Finally, it closes by summarizing the findings of the above examinations, and suggests some recommendations for future works.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.25-35
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• 2001

This study aims to find out the growth characteristics of riparian plants on the artificial floating islands (AFI). Three types of experiments were performed. The vegetation growth were compared by the plant-supporting materials; natural cotton mat, coir mat on the AFI or in the water, and natural soil at the waterfront. Major findings are; 1. The survival rate of riparian plants was 100% on both coir-mat and cotton-matislands, which implies that we may substitute cheaper cotton for expensive coir-mat. 2. Both natural cotton mat and coir mat were good for the growth of plants. Especially, the natural cotton mat was good for Sparganium stoloniferum and Miscanthus sacchariflorus, and the coir mat was good for Typha latifolia. 3. The growth rate of stem and root showed difference between the stem-removed plants and stem-remaining plants. As a whole, the growth rate of stem-removed plants was bigger than the one of stem-remaining plants. 4. The growth rate of plants showed difference between those grown on the AFI and those grown in the water. The growth rate of plant on the AFI was bigger than the one in the water. 5. The growth rate of plants on the AFI was bigger than the one on the natural soil at the waterfront.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.1
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• pp.57-66
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• 2001

The floating islands have been constructed for the water quality improvement and the biodiversity conservation in an disturbed aquatic ecosystem. We made floating islands consisted of a special float and substrates of coconut fibers implanted with four emergent macrophytes such as Phragmites australis, Zizania latifolia, Iris pseudoacorus, Typha angustifolia. Vegetation structure and plant growth were compared between on the floating islands and on ground in order to select suitable plants for the construction of floating islands. Emergent-macrophytic vegetation on the floating islands showed lower coverages and higher plant biodiversity due to natural introduction of various hydrophytes and hygrophytes. Shoot density was increased on floating islands except for Zizania latifolia. From the point of coverage and density of plants, Phragmites australis and Iris pseudoacorus were suitable for floating islands. Total biomass of emergent macrophytes was decreased on the floating islands. The belowground/aboveground biomass ratio of floating islands was higher than that of the ground. Out of planted macrophytes, Iris pseudoacorus with a high belowground/aboveground biomass ratio could be evaluated a suitable plant for the floating islands because a plenty of its root is profitable to adapt with the nutrient-limited environment of floating islands.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.1
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• pp.1-7
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• 2002

The effects of floating islands on the changes in phytoplankton community structure were investigated in a small artificial pond. The floating islands planted with various emergent macrophytes covered 35% of total water surface area of the pond. Total 17 genera and 25 species of phytoplankton were found in the pond, of which Dinophyceae was 1 genera and 1 species, Cyanophyceae 1 genera and 1 species, Bacillariophyceae 6 genera and 8 species, and Chlorophyceae 9 genera and 15 species. Dominant phytoplanktons under floating islands were changed from Aphanizomenon sp. as a Cyanophyceae to Golenkinia radiata, Kirchneriella contorta and Micractinium pusillum as a Chlorophyceae for 56 days after the construction of floating islands on July 24, 2001. The changes of dominant phytoplanktons of the control without floating islands were similar to those under floating islands in July and August, but Aphanizomenon sp. was rapidly increased in the control sites in September. About 99% of the cell number of Aphanizomenon sp. was disappeared for a month after construction of floating islands. Species diversity of phytoplankton under the floating islands of Iris pseudoacorus was higher than those of other macrophytes as well as the control without floating islands. The cell numbers of Cyanophyceae and Chlorophyceae were fewer under the floating islands of I. pseudoacorus than those of other macrophytes. Our results showed that the floating islands could be a useful eco-technique for the control of water bloom by Cyanophyceae and Chlorophyceae in a pond ecosystem.

• Strategy21
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• s.42
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• pp.154-195
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• 2017

This paper is to analyse conflict between the US and China over the South China Sea and Korea's responses. To this end the paper is composed of 6 chapters titled instruction; the current status of South China Sea sovereignty disputes; changes in US and Chinese maritime security strategies and the strategic values of the South China Sea; key issues and future prospects for US-China conflicts in the South China Sea; South Korea's security and diplomatic responses; and conclusion. The recent East Asian maritime security issue has evolved into a global issue of supremacy between the US and China, beyond conflicts over territorial disputes and demarcation among the countries in the region. China is pursuing offensive ocean policy to expand economic growth. The core of the maritime order that the United States intends to pursue is the freedom of navigation in the oceans and the maintenance of maritime access. China is making artificial islands in the South China Sea, claiming the sovereignty of these islands, building strategic bases in East Asia, and securing routes. The United States has developed several "Freedom of Navigation Operations" to neutralize the declaration of the territorial sea surrounding Chinese artificial islands. We can not be free from marine conflicts in the South China Sea and the East China Sea. Regarding the South China Sea dispute, it is expected that the strategic competition and conflict between the two countries will intensify due to China's failure to make concessions of core interests and adherence to the US compliance with international norms. In the midst of conflict over the South China Sea, we need a harmonious balance between our alliance security and economic diplomacy. We must continue our efforts to strengthen the ROK-US alliance but not to make China an enemy. Considering the significant impacts of the oceans on the survival and prosperity of the nation, we must continue to develop our interest in the oceans, appropriate investments and tactical strategies.

• Proceedings of the Korean Geotechical Society Conference
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• 1992.10a
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• pp.3-10
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• 1992

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.3
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• pp.190-200
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• 2022

In this study, the island's land-use and land-cover change (LULCC) is analyzed in South Korea using remotely sensed land cover data(Globeland 30) acquired from 2000 to 2020 to meet the requirement of providing practical information for forest management. Analysis of LULCC between the 2000 and 2020 images revealed that changes to agricultural land were the most common type of change (7.6% of pixels), followed by changes to the forest (5.7%). The islands forests maintain 157,246 ha (42.2% of the total island area). Land cover types that changed to the forest from grasslands were 262 islands, while reverse cases have occurred on 421 islands. These 683 islands have a possibility of transition and disturbance. The artificial land class was newly calculated in 22 islands. The forests, which account for 42.2% of the 22 island area, turned into grassland, and 27.8% of agricultural land and grassland turned into forests. The development of artificial land often affects developed areas and surrounding areas, resulting in deforestation, management of agriculture, and landscaping. This study can provide insights concerning the fundamental data for assessing ecological functions and constructing forest management plans in islands ecosystems.