• 한국지형학회지
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• 제25권2호
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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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• 제24권1호
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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.

• 한국지형학회지
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• 제25권4호
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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.

• 한국환경생태학회지
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• 제37권5호
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• pp.403-414
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• 2023

본 연구는 강원도 강릉시에 위치한 하시동·안인사구 생태경관보전지역에서의 생태계서비스 평가와 증진방안 마련을 위하여 시행되었다. 연구방법으로 신속평가 도구를 이용한 생태계서비스 평가를 바탕으로 환경지속성지수 분석하였고, SWOT 분석을 통하여 생태계서비스 증진방안을 마련하였다. 하시동·안인사구 생태경관보전지역의 생태계서비스 평가 결과를 바탕으로 분석한 환경지속성지수는 조절서비스, 문화서비스, 지지서비스 모두 50% 미만으로 낮게 평가되었다. 특히 문화서비스, 지지서비스가 부족한 것으로 나타났다. 이러한 결과를 바탕으로 하시동·안인사구 생태경관보전지역의 생태계서비스 증진 방안을 마련하기 위하여 SWOT 분석을 시행하였다. 강점을 기회로 활용(SO전략), 강점을 이용한 위협요인 최소화(ST전략), 강점을 보완하기 위하여 기회를 활용(WO전략), 약점을 보완하고 위협을 최소화(WT전략)하는 생태계서비스 증진방안 6가지를 도출하였다. 향후 하시동·안인사구 생태경관보전지역에서 생태계서비스 증진사업을 추진할 때 현재 훼손된 지역의 복원과 향후 침식 등으로 인한 피해 방지 등 제시한 문제를 극복하고 이를 통하여 생태계서비스를 증진시켜 하시동·안인사구 생태경관보전지역의 가치를 높일 필요가 있다.

• 환경생물
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• 제25권4호
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• pp.356-362
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• 2007

충남 태안군 일대 4곳의 해안사구 지역에서 자생하는 9종의 사구식물 연관 근권세균 다양성을 2003년 10월부터 2004년 3월까지의 기간 동안 3차례에 걸쳐 denaturing gradient gel electrophoresis (DGGE) 기법을 이용하여 조사하였다. 그 결과 한 밴드가 계속 모든 시료에서 우점하는 것으로 나타났으며, DNA 염기서열 분석에 의하여 Lysobacter enzymogenes와 가장 유사한 것으로 나타났다. 기타 주요 밴드들은 Pseudomonas와 Bacillus 속의 균주들로 동정되었다. L. enzymogenes가 9종의 식물 모두에서 지역이나 조사시기에 관계없이 우점적으로 나타난 것은 이전의 클론 분석을 통한 결과와 일치한다 (Lee et al. 2006a). Bacillus에 속한 밴드들이 모든 조사에서 출현하였으며, Pseudomonas 속 밴드들은 2003년 12월 조사에서 두드러졌다. DGGE 분석만으로는 Lysobacter가 사구식물에 가지는 중요성을 파악할 수는 없으나 건강한 개체에 지속적으로 발견되는 것으로 보아 Lysobacter의 존재는 식물에 긍정적인 영향을 가지는 것으로 사료된다.

• Computers and Concrete
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• 제32권6호
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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.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2008년도 제49회 학술심포지움 및 국제학술대회
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• pp.21.1-21.1
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• 2008

• 한국환경복원기술학회지
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• 제8권6호
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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.

• 한국지형학회지
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• 제18권3호
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• pp.83-92
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• 2011

본 연구는 경상북도 동해안에서 가장 규모가 큰 영덕군 고래불 모래해안을 대상으로, 사빈과 해안사구의 지형 기복 및 해안 퇴적물의 특성과 변화를 분석하였다. 모래의 입도를 분석한 결과, 고래불 해안은 강원도 동해안과는 달리, 여름을 제외한 대부분 계절에 파랑과 연안류가 북류하면서 사빈의 모래 이동과 퇴적을 유발하였고, 여름에는 남북간의 흐름이 둔화되거나 남류가 발생하는 것으로 나타났다. 사빈에서는 여름철에 태풍이나 폭풍으로 인한 침식작용이 발생하였고 상대적으로 조립의 모래가 퇴적되는 것으로 나타났으며, 가을철과 겨울철에는 모래의 퇴적이 활발하게 발생하는 것으로 분석되었다. 해안사구의 전면부에서는 모든 계절에 해풍에 의해 모래가 퇴적되었으며, 특히 겨울철에 퇴적작용이 가장 활발하였다.

• 한국환경생태학회지
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• 제26권4호
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• pp.576-587
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• 2012

임자도 대광사구의 현존상관식생은 해안 방풍림으로 조성된 곰솔군락이 가장 넓게 분포하고 아까시나무군락, 갯그령군락, 띠-갯그령군락, 통보리사초군락, 갯쇠보리군락, 띠군락, 갈대군락, 띠-산조풀군락이 띠모양 또는 파편화로 분포하였다. 조사지점 74개소에 대해 식물사회학적 방법으로 자료를 수집 및 분석한 결과, 대광사구식생의 종조성은 7개군락, 5개군으로 총 10개 식생단위로 유형화되었다. 7개 군락은 곰솔군락, 갯그령군락, 아까시나무군락, 해당화군락, 갯쇠보리군락, 통보리사초군락, 산조풀군락으로 구분되었으며, 곰솔군락의 하위단위로 고사리군, 갯그령군, 곰솔전형군의 3개군과 산조풀군락의 하위단위로 갈대군, 산조풀전형군의 2개군으로 구분되었다. 종의 해안선으로부터 대상분포는 갯그령 - 통보리사초, 좀보리사초 - 갯완두 - 갯메꽃 - 순비기나무, 갯완두, 갯쇠보리 - 해당화 순으로 나타났다. 종단면을 분석한 결과, 전사구의 초본식생의 폭이 넓고, 전사구 전면부의 경사가 완만하며, 사구열이 많고, 구조물이 없는 유형이 사구의 침식에 덜 취약하고, 회복에 유리한 것으로 나타났다.