• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.66-78
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• 2011

It is getting difficult to manage water resources in South Korea because more than half of annual precipitation is concentrated in the summer season and its intensity is increasing due to global warming and climate change. Artificial recharge schemes such as well recharge of surface water and roof-top rainwater harvesting can be a useful method to manage water resources in Korea. In this study, potential artificial recharge site is evaluated using geographic information system with hydrogeological and social factors. The hydrogeological factors include annual precipitation, geological classification based on geological map, specific capacity and depth to water level of national groundwater monitoring wells. These factors were selected to evaluate potential artificial recharge site because annual precipitation is closely related to source water availability for artificial recharge, geological features and specific capacity are related to injection capacity and depth to water is related to storage capacity of the subsurface medium. In addition to those hydrogeological factors, social aspect was taken into consideration by selecting the areas that is not serviced by national water works and have been suffered from drought. These factors are graded into five rates and integrated together in the GIS system resulting in spatial distribution of artificial recharge potential. Cheongsong, Yeongdeok in Gyeongsangbuk-do and Hadong in Gyeongsangnam-do, and Suncheon in Jeollanam-do were proven as favorable areas for applying artificial recharge schemes. Although the potential map for artificial recharge in South Korea developed in this study need to be improved by using other scientific factors such as evaporation and topographical features, and other social factors such as water-curtain cultivation area, hot spring resorts and industrial area where groundwater level is severely lowered, it can be used in a rough site-selection, preliminary and/or feasibility study for artificial recharge.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.413-420
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• 2008

The phytosociological study was carried out to investigate the structural characteristics of paddy levee vegetation in South Korea. The vegetation data of total 59 releves were analyzed by the Zurich-Montpellier school's method. 6 syntaxa (3 associations and 3 communities) of paddy levee were recognized : Echinochlo-Digitaretum ciliaris ass. nov. hoc., Artemisia princeps-Erigeron annus community, Imperata cylindrica v. koenigii community, Glycine soja-Humulus scandens community, Miscantheum sinensis f. purpurascens ass. nov. hoc,, Polygonetum thunbergii Lohm. et Miyawaki 1962. Detrended correspondence analysis(DCA) showed that Artemisia princeps-Erigeron annus community and Imperata cylindrica v. koenigii community were positively correlated with soil hardness. Polygonetum thunbergii Lohm. et association and Miscantheum sinensis f. purpurascens ass. nov. hoc. was intimately correlated with high soil total nitrogen.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.6
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• pp.808-820
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• 2006

In regard to indoor air quality patterns, the government introduced various polices that were about managing and monitoring quality of indoor air as a major assignment, and also executed 'Indoor Air Quality Management Act' which was presented in the May, 2004. However, among the multi-usage facilities controlled by the Act, the school was not included yet. This study goal was to investigate PM 10 pollution patterns of the high school classrooms using a pattern recognition method based on cluster analysis and disjoint principal component analysis, and further to survey levels of inorganic elements in May, June, and September, 2004. A hierarchical clustering method was examined to obtain possible objects in pseudo homogeneous sample classes by transformation raw data and by applying various distance. Following the analysis, the disjoint principal component analysis was used to define homogeneous sample class after deleting outliers. Then three homogeneous Patterns were obtained as follows: the first class had been separated and objects in the class were considered to be sampled under semi-open condition. This class had high concentration of Ca, Fe, Mg, K, Al, and Na which are related with a soil and a chalk compounds. The second class was obtained in which objects were sampled while working air-conditioners and was identified low concentration of PM 10 and elements. Objects in the last class were assigned during rainy day. A chalk, soil element and various types of anthropogenic sources including combustions and industrial influenced the third class. This methodology was thought to be helpful enough to classify indoor air quality patterns and indoor environmental categories when controlling an indoor air quality.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.997-1000
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• 2008

Strength development of concrete subjected to cold weather is generally delayed due to its low temperature. In case of soil nailing method, it is necessary to apply the shotcrete. However, the shotcrete placement under low temperature experiences retardation of strength development due to delayed hydration reaction. Therefore, in this paper, the use of fine particle cement which is produced through particle classification in cement manufacturing process, is discussed to enhance the strength development of the shotcrete under low temperature. According to the results, the concrete containing 100% of fine particle cement had excellent strength development even at $-9^{\circ}C$ of temperature and at 5days, it reached design strength with PE film curing. It is thought that more than 70% of fine particle cement can secure required strength of the shotcrete even at low temperature condition.

• Korean Journal of Environment and Ecology
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• v.11 no.4
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• pp.462-468
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• 1998

Vegetational data from 25 quadrats of Quercus mongolica communities at Hangyeryong and Paekdamsa area in Soraksan National Park were analysed by applying two multivariate methods: two-way indicator species analysis(TWINSPAN) for classification and canonical correspondence analysis(CCA) for ordination. The forest vegetation of Quercus mongolica community was classified into Quercus mongolica-Tilia amurensis, Quercus mongolica-Abies holophylla, Quercus mongolica-Styrax obassis, and Quercus mongolica-Quercus serrata groups according to the TWINSPAN. The relationships between the distribution of dominant groups according ot the TWINSPAN. The relationships between the distribution of dominant groups for forest vegetation and soil condition in Quercus mongolica communities were investigated by analysing elevation and soil nutrition gradients. Quercus mongolica-Tilia amurensis group was distributed in the high elevation and poor nutrition area of total nitrogen and C.E.C., Quercus monholica-Abies holophylla group was distributed in the high elevation and good nutrition area of total nitrogen and C.E.C., Quercus mongolica-Styrax obassia group was distributed in the medium elevation and poor nutrition area of total nitrogen and C.E.C., while Quercus mongolica-Quercus serrata group was distributed in the low elevation and poor nutrition area of total nitrogen and C.E.C.. The dominant factors influencing community distribution were elevation, total nitrogen and C.E.C..

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.250-262
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• 2015

This study aims to investigate the characteristics of the vegetation structure in the sectin stretching between the Jilmoi wetlands and the Donghae Observatory and to set the criteria for the basic data for a management plan including restoration afterwards. 12 plots($10m{\times}40m$, $20m{\times}20m$) were set up to analyse the vegetation structure. The analysis of the classification by TWINSPAN and ordination by DCA, importance percentage and property, distribution of diameter of breast height, growth increments of major woody species, species diversity and the physicochemical properties of soil were all analyzed. Vegetation classes were divided into 3 communities, which are community I (Pinus densiflora community), community II (Quercus mongolica community) and community III (Quercus mongolica-Tilia amurensis community). The P. densiflora community declined when competing with Q. mongolica and Fraxinus rhynchophylla and Q. mongolica competed with T. amurensis on an understory layer in Q. mongolica community. Q. mongolica competed with T. amurensis on both canopy and understory layers in Q. mongolica-T. amurensis community. P. densiflora declined and it was assumed to succeed to F. rhynchophylla or T. amurensis through Q. mongolica based on the importance percentage and distribution of the diameter of the breast height of small and middle sized trees. The age of P. densiflora was between 47 to 51 years old and Q. mongolica was 61years old. T. amurensis was 61 years old and the growth of Q. mongolica slowed a little. As the result of Shannon's index of species diversity, community I ranged from 0.9578 to 1.1862, community II ranged from 0.7904 to 1.2286 and community III ranged from 0.8701 to 1.0323. The contents of organic matter and cation were low compared to uncultivated mountain soil and it were analysed to be inappropriate for tree growth.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.14-20
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• 2009

Classification of land uses and analysis of nitrogen isotope fractionation in groundwater nitrate were carried out to examine its contamination sources in Jeju province. ${\delta}^{15}N$ values of urea (hydrolyzed with urease), ammonium sulfate, compost, water from septic tank were -1.7, -5.8, +14.1, and +24.0‰, respectively. Urea, when it was directly distillated, showed -16.5‰. Based on these ${\delta}^{15}N$ values, sources of nitrate could be classified as originated from chemical fertilizers with ${\delta}^{15}N$ values below +5‰ and as from animal manure or municipal waste with ${\delta}^{15}N$ values over +10‰. Results of ${\delta}^{15}N$ analysis of 33 wells showed that most wells had the chemical fertilizers as their dominant contamination source. However, some wells were contaminated by other sources: animal wastes or municipal wastes. Some wells were also contaminated by the combined sources of nitrate. It was also demonstrated that ${\delta}^{15}N$ analysis could be a useful tool even in the case where no apparent contamination source is found.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.3
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• pp.29-45
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• 2022

For biodiversity conservation, the importance of beta-diversity which is changes in the composition of species according to environmental changes has become emphasized. However, given the systematic investigation of species distribution and the accumulation of large amounts of data in the Republic of Korea(ROK), research on the spatialization of beta-diversity using them is insufficient. Accordingly, this research investigated the applicability of the Generalized Dissimilarity Modeling(GDM) to ROK, which can predict and map the similarity of compositional turnover (beta-diversity) based on environmental variables. A brief overview of the statistical description on using GDM was presented, and a model was fitted using the flora distribution data(410,621points) from the National Ecosystem Survey and various environmental spatial data including climate, soil, topography, and land cover. Procedures and appropriated spatial units required to improve the explanatory power of the model were presented. As a result, it was found that geographical distance, temperature annual range, summer temperature, winter precipitation, and soil factors affect the dissimilarity of the vegetation community composition. In addition, as a result of predicting the similarity of vegetation composition across the nation, and classifying them into 20 and 100 zones, the similarity was high mainly in the central inland area, and tends to decrease toward the mountainous areas, southern coastal regions, and island including Jeju island, which means the composition of the vegetation community is unique and beta diversity is high. In addition, it was identified that the number of common species between zones decreased as the geographic distance between zones increased. It classified the spatial distribution of plant community composition in a quantitative and objective way, but additional research and verification are needed for practical application. It is expected that research on community-level biodiversity modeling in the ROK will be conducted more actively based on this study.

• Journal of Soil and Groundwater Environment
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• v.27 no.6
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• pp.22-36
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• 2022

Water resources in Jeju Island are dependent virtually entirely on groundwater. For groundwater resources, drought damage can cause environmental and economic losses because it progresses slowly and occurs for a long time in a large area. Therefore, this study quantitatively evaluated groundwater level fluctuations using principal component and cluster analyses for 42 monitoring wells in Jeju Island, and further identified the types of groundwater fluctuations caused by drought. As a result of principal component analysis for the monthly average groundwater level during 2005-2019 and the daily average groundwater level during the dry season, it was found that the first three principal components account for most of the variance 74.5-93.5% of the total data. In the cluster analysis using these three principal components, most of wells belong to Cluster 1, and seasonal characteristics have a significant impact on groundwater fluctuations. However, wells belonging to Cluster 2 with high factor loadings of components 2 and 3 affected by groundwater pumping, tide levels, and nearby surface water are mainly distributed on the west coast. Based on these results, it is expected that groundwater in the western area will be more vulnerable to saltwater intrusion and groundwater depletion caused by drought.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.4
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• pp.58-69
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• 2018

The purpose of this study was to present specific standards for landscape planning and construction applicable to landscaping areas in various historical sites. The results are as follows: First, the types of historical sites are classified according to their preservation status and processing techniques, and the classification according to their status is divided into those that have been buried underground, such as those that have been exposed to the ground, such as buildings and structures, and those that have a reputation or a record of the sites. The classification according to the wartime processing technique was classified by such techniques as closures that isolate the site, penetration that can be seen on the site, and overlays where a separate protection facility is installed on the site. Second, the principles of landscape planning for display of historical sites are divided into the items that make up the historical site, surface treatment of the sites, tree planting, and installation of facilities. If the site is not a circular space, the area separating the space by different materials between the components is required. In the event that preservation of the historical site is required, it is deemed desirable to use the soil, and to do so, the use of grasses and shrubs is effectively considered to be effective. The introduction of plants and plants should be considered according to the nature of the space. Depending on the area and nature of the monument, the facility is required to take a cautious approach by reviewing its influence on the landscape and the additional excavation of the monument. Third, the readjustment method derived as a result of looking at the landscaping principle in the historical site space was classified as conservation of status, installation of protection facilities, burial, restoration, relocation, and reproduction. Preservation of the status quo is essential for limited landscape planning and should not affect the prototype of existing relics. The protection facility shall be installed where necessary to protect the relics, and when the soil is formed, the surface treatment shall be required to remove trees that could damage the site and prevent soil and soil oil from being lost after the site. The restoration shall establish a landscaping plan according to the circular preservation based on the clues to the circle. The transfer requires a landscaping plan to create an environment similar to the outer space of an existing site and should be able to highlight the value or location of the original site. The reenactment should have a landscaping plan to revive the landscape and atmosphere of the past for the now-defunct remains. Fourth, landscaping can simultaneously satisfy the preservation of excavation sites and the increase in exhibition effects. In order to protect the traces of the past and vitalize the site of the ruins today, specific measures are required, the creation of a park for historical sites that preserve the functions and value of the relics, and the formation of a shape of linked contents can be suggested as alternatives.