• 수산해양교육연구
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• 제22권2호
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• pp.180-194
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• 2010

Coastal sand dunes are dynamic and fragile buffer zones of sand and vegetation where the following three characteristics can be found: large quantities of sand, persistent wind capable of moving sand, and suitable locations for sand to accumulate. The functional properties of coastal sand dunes include the roles in sand storage, underground freshwater storage, coastal defense, and ecological environment space, among others. Recently, however, the integrity of coastal dune systems has been threatened by development, including sand extraction for the construction industry, military usage, conversion to golf courses, the building of seawalls and breakwaters, and recreational facility development. In this paper, we examined the development mechanisms and structural/format types of coastal sand dunes, as well as their functions and value from the perspective of coastal engineering based on reviews of previous researches and a case study of a small coastal sand dune in the Nakdong river estuary. Existing data indicate that there are a total of 133 coastal sand dunes in South Korea, 43 distributed on the East Sea coast (32 in the Gangwon area, and 11 in Gyeongsangbuk-do), 60 on the West Sea coast (4 in Incheon and Gyeonggi-do, 42 in Ghungcheongnam-do, 9 in Jellabuk-do, and 5 in Jellanam-do), and 30 on the South Sea coast (16 in Jellanam-do, 2 in Gyeongsangnam-do, and 12 in Jeju).

• Journal of Ecology and Environment
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• 제47권3호
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• pp.103-116
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• 2023

Background: This study analyzed the physiological adaptations of a woody plant, Vitex rotundifolia, in Goraebul coastal sand dunes from May to September 2022. Environmental factors and physiological of plants growing under field and controlled (pot) conditions were compared. Results: Photosynthesis in plants growing in the coastal sand dunes and pots was the highest in June 2022 and July 2022, respectively. Chlorophyll fluorescence indicated the presence of stress in the coastal sand dune environment. The net photosynthesis rate (P_N) and Y(II) were highest in June in the coastal sand dune environment and July in the pot environment. In August and September, Y(NPQ) increased in the plants in the coastal sand dune environment, showing their photoprotective mechanism. Chlorophyll a and b contents in the pot plant leaves were higher than those in the coastal sand dune plant leaves; however, chlorophyll-a/b ratio was higher in the coastal sand dune plant leaves than in the pot plant leaves, suggesting a relatively high photosynthetic efficiency. Carotenoid content in the coastal sand dune plant leaves was higher in August and September 2022 than that in the pot plant leaves. Leaf water and soluble carbohydrate contents of the coastal sand dune plant leaves decreased in September 2022, leading to rapid leaf abscission. Diurnal variations in photosynthesis and chlorophyll fluorescence in both environments showed peak activity at 12:00 hour; however, the coastal sand dune plants had lower growth rates and Y(II) than the pot plants. Plants in the coastal sand dunes had higher leaf water and ion contents, indicating that they adapted to water stress through osmotic adjustments. However, plants growing in the coastal sand dunes exhibited reduced photosynthetic activity and accelerated decline due to seasonal temperature decreases. These findings demonstrate the adaptation mechanisms of V. rotundifolia to water stress, poor soils, and high temperature conditions in coastal sand dunes. Conclusions: The observed variations indicate the responses of the V. rotundifolia to environmental stress, and may reveal its survival strategies and adaptation mechanisms to stress. The results provide insights into the ecophysiological characteristics of V. rotundifolia and a basis for the conservation and restoration of damaged coastal sand dunes.

• 한국지형학회지
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• 제24권2호
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• pp.1-13
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• 2017

Massive coastal sand dunes are distributed in Ui-island, Shinan-gun. The sand dunes in Ui-island is worth studying, in terms of preserving natural environment without anthropogenic impacts. In this study, we surveyed geomorphological processes of the sand dune based upon measuring of geometric properties, grain size analysis, and OSL(Optically Stimulated Luminescence) age dating. The sediments of the dune consist mainly of well sorted medium sand with about 250$\mu$m. Based on spatial distribution of sand dunes, we found that they are formed by northwest monsoon during winter, and sands are supplied from Seongchon area in northern UI-island. According to OSL age dating, the sand dunes were deposited from $0.07{\pm}0.01ka$ to $0.17{\pm}0.04ka$. This result shows that the transformation of the dune due to the sand movement by wind was active during the last 100-200 years. The aerial photograph indicates that the dimension of the largest sand dune has decreased since 1945. Further research is needed to get more detailed information on geomorphic changes of sand dunes in UI-island.

• 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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• 제27권2호
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• pp.47-64
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• 2020

The Baengnyeongdo-island, located at the northernmost point of the west coast, has developed several coastal landforms. Although the coastal landforms of Baengnyeongdo-island are widely used as a tourism resource, a lot of academic research has not been conducted. In this study, particle size analysis, XRF, and OSL age dating were performed on the BR sandy deposits to find out the formation of coastal sand dunes on Baengnyeongdo-island. Based on the physicochemical properties, the BR section was divided into three parts; BR-A, BR-B and BR-C. First, about 56ka, which corresponds to the MIS 3, fine sand was deposited and forms the BR-C section. Second, the BR-B which located middle part of BR section, showed reversed age stratigraphy. The BR-B was interpreted as reworked sediments based on sedimentary facies and chemical weathering intensity. And, the BR-A composed of fine and medium sands was formed in middle Holocene. This research has significance in that it finds out the paleo sand dunes formed in Pleistocene. This study can contribute to understanding coastal sand dune development on the west coast.

• Journal of Ecology and Environment
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• 제35권3호
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• pp.167-175
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• 2012

Coastal sand dune systems are particularly fragile and threaten the environment. However, these systems provide fundamental ecosystem services to the nearby urban areas, acting, for example, as protective buffers against erosion. In this paper, we attempt to classify the biotope types of coastal sand dune ecosystems and select an index for the assessment of the conservation value. The types of biotopes are categorized based on the vegetation map; floras are examined in order to research the effects of hinterlands on coastal sand dunes. In addition, a naturalization rate and an urbanization index for each biotope type in hinterlands are analyzed. In the ecosystem of coastal sand dunes, the urbanization index and naturalization rate shows a higher value in sand dunes with areas of road, residential, and idle land in farm villages, rice fields, and fields. On the contrary, a lower value in the urbanization index and naturalization rate is present when typical biotope types, such as sand dune vegetation and natural Pinus thunbergii forests, are widely distributed. Based on these results, urbanization index and naturalization rate should be used as critical indices for the assessment of the ecosystem of costal sand dunes.

• 한국측량학회지
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• 제35권1호
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• pp.11-22
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• 2017

In recent years, coastal dune erosion has accelerated as various structures have been developed around the coastal dunes. A land cover map should be developed to identify the characteristics of sand dunes and to monitor the condition of sand dunes. The Korean Ministry of Environment's land cover maps suffer from problems, such as limited classes, target areas, and durations. Thus, this study conducted experiments using RGB and multispectral images based on UAV (Unmanned Aerial Vehicle) over an approximately one-year cycle to create a land cover map of coastal dunes. RF (Random Forest) classifier was used for the analysis in accordance with the experimental region's characteristics. The pixel- and object-based classification results obtained by using RGB and multispectral cameras were evaluated, respectively. The study results showed that object-based classification using multispectral images had the highest accuracy. Our results suggest that constant monitoring of coastal dunes can be performed effectively.

• Journal of Species Research
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• 제11권1호
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• pp.61-66
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• 2022

Three localities of coastal sand-dunes along the western coastline of Korea: Sindu-ri, Sinhap-ri, and Jaeun-do, were surveyed for the lepidopteran fauna. This survey resulted in the records of five species new to Korea: a species of Cosmopterigidae, Cosmopterix flavidella Kuroko, 2011, based on eight specimens from Sinhap-ri and Jaeun-do; a species of Tortricidae, Noduliferola abstrusa Kuznetzov, 1973, based on five specimens from Sinhap-ri and Jaeun-do; a species of Pyralidae, Maliarpha borealis Sasaki, 2012, based on four specimens from Sindu-ri; and two species of Erebidae, Ectoblemma rosella Sugi, 1982 and Metachrostis miasma (Hampson, 1891), based on one specimen for each from Jaeun-do. Three genera, Noduliferola Kuznetzov, 1973, Maliarpha Ragonot, 1888 and Ectoblemma Sugi, 1982, are introduced for the first time to the Korean fauna. Two species, Noduliferola abstrusa and Maliarpha borealis, are suggested as the indicator species for coastal sand-dunes. The superficial and genital features of the five species found from this study are described and illustrated. A photograph of the female genitalia of Ectoblemma rosella is provided for the first time.

• 한국지형학회지
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• 제28권1호
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• pp.51-66
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• 2021

This study shows that coastal sand dunes are negatively affected by coastal forests. In South Korea, planting pine trees on the dunes has been carried out to stabilize the dune landscapes and protect residential areas from coastal disasters since the 20th century. However, this strategy could reduce the resilience of dunes. In this study, we selected three monitoring sites with automated weather stations to compare the geomorphological and environmental characteristics between tree-covered and grass-covered dunes at Sohwang-ri, Boryeong-si, Chungnam Province for three years. In addition, we monitored the rates of erosion and deposition using eight pins along the dune crests. We found that the forest affected both wind velocity and direction, resulting in decreased blown sand supply to the dunes in front of the forest. The velocity of the strong winds faster than 5 m/s diminished to 10%-30% of the control sites, and the direction of northwesterly wind were skewed to the north by about 6°. Sand deposition occurred at about 15-20 m away from the pine forest and the amount was only 1/10 of the deposition within the grass-covered dunes. This study suggests that planting trees in coastal dunes is an undesirable strategy with negative impacts on the landscape management.

• 한국지반신소재학회논문집
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• 제23권3호
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• pp.31-42
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• 2024

해안사구는 해안사빈의 모래가 바람에 의해 운반 및 퇴적으로 형성되어 생태계 보전 및 자연재해 보호의 역할을 한다. 해안사구의 침식에 대한 자가회복력에도 불구하고 해안사구의 면적이 지속적으로 감소하고 있어 논의가 필요하다. 미생물을 활용한 탄산칼슘 형성(microbially induced carbonate precipitation, MICP) 기술은 지반의 강성과 강도를 증진시키는 친환경적 방법으로, 본 논문에서는 MICP 기술의 해안사구 침식 저감성에 대해 논의하였다. 풍동 시험기가 해안사구의 침식 거동을 모사하기 위해 사용되었다. 무처리 모래와 MICP 처리 모래를 준비하여 침식 실험을 수행하였다. 3차원 스캐너를 통해 침식 전후의 표면 변화를 관측하여 침식 거동과 침식성 정수를 분석하였다. 염산 세척을 통해 MICP 처리된 모래의 고결도를 정량화 하였다. 실험 결과, MICP 처리가 높을수록 고결도와 강도가 올라가고, 그로 인해 침식 저항성이 증진되었다. 이 논문에서는 풍력에 의한 전단응력과 물에 의한 전단응력 간의 불일치를 발견하고 이를 해소하기 위하여 보정계수를 제안하였다. 본 연구를 통해 MICP 기술의 해안사구의 침식 저감 가능성을 확인하였다.