• Journal of The Geomorphological Association of Korea
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• v.25 no.2
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• pp.63-80
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• 2018

The purpose of this study was to investigate the physicochemical characteristics and formation age of sand dunes in the Okjukdong and Dajindong, Daecheong Island. As a result, most of the sand deposited in Okjukdong were composed of medium sized sand with moderately well sorted. The $SiO_2$ and $Al_2O_3$ accounted for a very high proportion of these deposits. There were some differences in characteristics between the sands in the dune and beach, whereas similar characteristics were observed among the materials (OJ-B, OJ-C and OJ-D) in the dune. In case of Dajindong, heterogeneous geochemical characteristics were found in the lower point. It was estimated that this was due to the influence of Daejin-dong black beach. Age dating results showed that uncovered dunes in Okjukdong were deposited $0.44{\pm}0.02$ ~ $0.50{\pm}0.02ka$, and sand depositsin Dajindong were formed $0.16{\pm}0.01$ ~ $0.18{\pm}0.01ka$. In both Okjukdong and Dajindong, sand deposits estimated to be formed 70 years ago, therefore it can be estimated that sand movement was active throughout the area from about hundred years ago. In this study area, the growth of sand dunes has been active in recent several decades or hundred years. It seems that there were different regions where deposits predominated over time. The source of dune sand was also different from time to time. Since the windbreak forest was established, the natural growth of sand dunes was limited, and sand nourishment was carried out by period. Therefore, in order to protect and continuously utilize coastalsand dunesin Daecheong Island, it is necessary to prepare conservation plan.

• Ocean and Polar Research
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• v.24 no.1
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• pp.79-86
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• 2002

It was found that 14 coastal habitats in South Korea have comparetively natural vegetation. The habitats were classified into three types - intertidal flats, sand dunes, and estuaries. There were four intertidal flats, five sand dunes and five estuaries. Except for Cynodon dactylon and Tetragonia tetragonoides, all of the main halophytes and sand dune plants were found in the habitats. These two species were mainly distributed on the southern coast. This study identified coastal vegetation, such as pure stands of Suaeda japonica on intertidal flats, mixed halophyte communities around the high-water mark, pure stands of Vitex rotundifolia on stable sand dunes, mixed communities dominated by Carex kobomugi on unstable sand dunes, and pure stands of Phragmites communis in estuaries. The types of coastal vegetation may depend on sediment types, the inundation time of seawater and the stability of sediments.

• Journal of The Geomorphological Association of Korea
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• v.25 no.4
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• pp.37-47
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• 2018

Coastal sand dunes have been regarded as natural defenses to protect hinterland from disasters such as storm surge and typhoons. However, many dunes are not well-deserved in South Korea because of imprudent land development or inappropriate measures after coastal erosion. Lately, beach nourishment and dune reinforcement are emphasized as the effective and environmentally sustainable solution for the coastal protection. They are regarded good strategies to keep landscapes for a time, with little side effects. However, there is little knowledge on the construction methods including proper design and time plans for the best results.In addition, the effects of dune reinforcement in the field should be tested.In thisstudy, we performed sand filling in an eroded dune scarp and surveyed topographic changes in the beach-dune system, which is located along Dasa-ri coast, Chungnam Province, South Korea. Using a network RTK-GPS and drone-based aerial photographs, we analyzed the temporal and spatial changes in the area, before and after the reinforcement. As a result, the dune reinforcement seems to be helpful to mitigates the coastal erosion and to prevent the coastline retreat at least for one year.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.403-414
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• 2023

This study aimed to evaluate the ecosystem services and environmental sustainability index(ESI) of the Hasidong-Anin coastal sand dune ecological and landscapes conservation area using rapid assessment tools. As a result, the analysis of the environmental sustainability index, derived from the evaluation of ecosystem services in the Hasidong-Anin coastal sand dune ecological and landscapes conservation area, revealed that regulating services, cultural services, and supporting services were all rated below 50%. Especially, cultural and supporting services were identified as lacking. With these results, a SWOT analysis was conducted to develop strategies for enhancing ecosystem services in the Hasidong-Anin coastal sand dune ecological and landscapes conservation area. Six approaches were formulated, involving leveraging strengths as opportunities (SO strategy), minimizing threats using strengths (ST strategy), utilizing opportunities to address weaknesses (WO strategy), and mitigating weaknesses and threats (WT strategy). In the future, when promoting projects to enhance ecosystem services in the Hasidong-Anin coastal sand dune ecological and landscapes conservation area, it will be essential to address issues such as the restoration of currently damaged areas and prevention of future erosion-related damages. This will lead to an elevation of the value of the Hasidong-Anin coastal sand dune ecological and landscape conservation area.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.356-362
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• 2007

The rhizobacterial diversity associated with 9 native plant species inhabiting coastal sand dunes in Tae-an area, Chungnam Province, was studied using the denaturing gradient gel electrophoresis (DGGE) fingerprinting analysis over three times from October 2003 to March 2004. One dominant band commonly occurred in all of the rhizosphere samples, which was identified as that of Lysobacter enzymogenes. The other common bands included those derived from species of Pseudomonas and Bacillus. It was notable that L. enzymogenes was dominant in all of the 9 plant species and such dominance was consistent throughout the whole sampling period, which confirms the previous study by Lee et al. (2006a). The Bacillus bands were detected in all of the three samplings, and those of Pseudomonas were notable in the samples of December 2003. By the DGGE analysis alone, the significance of Lysobacter to the sand dune plants is not clear. However, considering their presence in healthy plants and the dominance in all plant species, Lysobacter may have positive roles in the survival or growth of the plants in sand dune area.

• Computers and Concrete
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• v.32 no.6
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• pp.595-606
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• 2023

Dune sand (DS) has been widely used as a partial replacement for regular sand in concrete construction. Therefore, investigating its mechanical properties is critical for the analysis and design of structural elements using DS as a construction material. This paper presents a comprehensive investigation of the mechanical properties of DS concrete, considering different replacement ratios and strength grades. Regression analysis is utilized to develop strength prediction models for different mechanical properties of DS concrete. The proposed models exhibit high calculation accuracy, with R² values of 0.996, 0.991, 0.982, and 0.989 for cube compressive strength, axial compressive strength, splitting tensile strength, and elastic modulus, respectively, and an error within ±20%. Furthermore, a stress-strain relationship specific to DS concrete is established, showing good agreement with experimental results. Additionally, nonlinear finite element analysis is performed on concrete-filled steel tube columns incorporating DS concrete, utilizing the established stress-strain relationship. The analytical and experimental results exhibit good agreement, confirming the validity of the proposed stress-strain relationship for DS concrete. Therefore, the findings presented in this paper provide valuable references for the design and analysis of structures utilizing DS concrete as a construction material.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.21.1-21.1
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• 2008

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.6
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• pp.59-68
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• 2005

This study was carried out to investigate soil properties, ordination, and vegetation of the coastal sand dune in Sinduri, Taean-Gun. 1. The Orobanche coerulescens and Ixeris repens that are a peculiar species were found in Sinduri coastal sand dune and the Salix purpurea var. japonica that is an endemic species of korea was found in that place. The plant communities was categorized into seven groups, such as Rosa rugosa community, Vitex rotundifolia communit, Carex kobomugi community, Imperata cylndrica var. koenigii community, Carex pumila community, Artemisia capillaris community, and Calamagrostis epigeios community. 2. The soil organic matter, total nitrogen, available phosphorous concentrations, and cation exchange capacity were lower in the study sites than in forest soil of seashore. There was little difference in soil exchangeable Ca, Mg, and K concentrations between in the study site and in the forest soil of seashore. The soil pH was ranged from 5.69 to 7.63. The soil texture in the study site was sand or loamy sand. 3. The results of the correlation between Sinduri coastal sand dune community and environmental factor are as follows; the soil pH was the most effect to the community distribution, and CEC, total nitrogen, soil organic matter, and the amount of silt in soil have some correlation with community distribution. 4. The results of the correlation between Sinduri coastal sand dune community and soil characteristics are as follows; the Calamagrostis epigeios community was found in area that have high soil moisture content; the Rosa rugosa community was found in area that have high soil CEC, organic matter concentration, and total nitrogen concentration, and low soil pH; the Vitex rotundifolia community, Carex kobomugi community, and Artemisia capillaris community were found in area that have low soil CEC, organic matter concentration, and total nitrogen concentration, and high soil pH; the Imperata cylndrica var. koenigii community and Carex pumila community were found in area that have medium soil CEC, organic matter concentration, total nitrogen concentration, and soil pH.

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.83-92
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• 2011

The properties and changes of geomorphic relief and coastal deposits were analyzed at Goreabul sand beach in Yeongdeok-gun, the largest that in east coast of Kyungsangbuk-do Province. As the result of grain size analysis, in almost season except summer, the sands mainly deposited in Goraebul sand beach because longshore current drift northward contrary to Gangwon-do east coast, and summer longshore current is weak or change direction to south ward. Sand beach mostly came form erosion owing to typoon and storm and was deposit more coarse sand in the summer, and was produced deposition actively in the fall and winter. Front side of sand dune came from deposition on sand every season by sea breeze, especially in the winter.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.576-587
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• 2012

As being actual physiognomical vegetation on Daegwang sand dune in Imjado, the widest area is occupied by Pinus thunbergii community planted as windbreak forest whereas those communities such as Robinia pseudoacacia community, Elymus mollis community, Imperata cylindrica var. koenigii - Elymus mollis community, Carex kobomugi community, Ischaemum antephoroides community, Imperata cylindrica var. koenigii community, Phragmites communis community, Imperata cylindrica var. koenigii - Calamagrostis epigeios community occupy as band shape or patch. According to the result of the data collected and analyzed based on phytosociological method regarding 74 plots of survey area, the species composition of Daegwang sand dune vegetation is classified total 10 vegetation units comprises 7 communities and 5 groups. The 7 communities are classified into Pinus thunbergii community, Robinia pseudoacacia community, Rosa rugosa var. rugosa community, Ischaemum antephoroides community, Carex kobomugi community, Calamagrostis epigeios community, and the sub-units of Pinus thunbergii communities are classified into 3 groups of Pteridium aquilinum var. latiusculum group, Elymus mollis group, Pinus thunbergii topical group and the sub-units of Calamagrostis epigeios communities are classified into 2 groups of Phragmites communis group, Calamagrostis epigeios tipical group. The zonation of vegetation from coastal line indicated with the order of Elymus mollis - Carex kobomugi, Carex pumila, Lathyrus japonicus - Calystegia soldanella - Vitex rotundifolia, Lathyrus japonicus, Ischaemum antephoroides - Rosa rugosa var. rugosa. According to the analysis result of longitudinal section, it was found to be those types with wide width herbaceous vegetation of foredune, smooth slope of foredune, lots of dune ridges with no structure were less vulnerable to erosion of sand dune and advantageous to its recovery.