• Microbiology and Biotechnology Letters
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• 제36권4호
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• pp.268-275
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• 2008

In order to develop the multi-functional rhizobacteria that can exert positive effect on the growth of plants growing in the coastal sand dune located along East Coast of Korea, rhizospheral bacteria of 11 different plants from this area were isolated 1,330 rhizobacteria. Among these, 23 strains were able to produce auxin and had spectrum of antagonism toward various phytopathogenic microbes. To know the mechanism of this antifungal activity, these 23 strains were subjected to further analyses; 19 strains of these produced siderophore as determined by color reaction on CAS-blue plate, 4 strains produced antifungal cellulase as judged by color change on CMC-Congo red plate, 17 strains were able to utilized insoluble phosphate salts, also determined by clear zone formation on PVK medium. Identification of the strain was assigned to all 23 strains by l6s rDNA sequence analysed, and all were identified to be in the genus of Bacillus and Pseudomonas. One strain of these, denoted Pseudomonas fluorescens IB4-14, showed ACC deaminase activity which is known to be involved in the resistance of environmental stress such as salt and drought. Also, P. fluorescens IB4-l4 showed the germination stimulation and roots growth promoting activity on the in vivo assay of Lysimachia mauritiana Lam. (spoonleaf yellow loosestrife).

• Journal of Forest and Environmental Science
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• 제30권4호
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• pp.383-392
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• 2014

In this study, we investigated the Fukiage sand dunes of southern Kyushu, Japan. We surveyed the status of recovery of coastal Japanese black pine forests damaged by pine wilt disease and their disaster prevention capability. We placed two transects: Transect 1, in an area that was severely damaged (80-90% damage rate) by pine wilt disease, and Transect 2, in an area that was mostly undamaged (<10% damage rate). Then, we installed survey lines, carried out vegetation surveys, and measured the depth and pH of humus soil. The survey lines were placed perpendicular to the coastline from the top of the fore-dune to the inland area, and divided into five 50 m sections. Before the point 100 m inland from the top of the fore-dune, the number of invasive hardwoods and of Japanese black pines were small because of the poor growth environment in both transects. Past the 100 m point, the species and number of Japanese black pines and broad-leaved trees increased further inland because the growth environment improved. In addition, the recovery metrics of tree height, diameter at breast height, age, and number in Transect 1 were much lower than those in Transect 2, and the basal area of broad-leaved trees and the depth of humus soil in Transect 1 were lower than in Transect 2, and the soil pH of humus soil in Transect 1 was higher than that of Transect 2. The shape ratio of the Japanese black pine forests indicated that they were insufficient for disaster prevention. Therefore, in order to fully promote the disaster prevention capability of coastal Japanese black pine forests, we should not only focus on prevention of pine wilt disease but also undertake continuous control efforts taking into consideration the sound growth environment such as appropriate density and soil management and removal of invasive broad-leaved trees.

• Journal of Wetlands Research
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• 제22권2호
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• pp.66-72
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• 2020

The coastal sand dunes have transitional characteristics of marine and inland ecosystems, and they have abundant biodiversity. This study investigated flora and vegetation and analyzed the landscape structure at seven beaches in Busan metropolitan city. As a result, the vascular species of the coastal sand dunes in Busan were identified as 178 taxa of 140 families. Vegetation landscape was damaged to the extent that no natural vegetation was found in 4 of 7 beaches (57%). The coastal dune vegetation was dominated by the Carex pumila community and Carex kobomugi community. The halophyte and invasive alien species were classified into 18 taxa (10% of all species) and 40 taxa (22% of all), respectively. The vegetation that made up the largest area was the Phragmites communis community of the salt marsh, and the species number of halophyte increased as the wetland area increased. This means that the maintenance and management of salt marshes is important to conserve the unique plant diversity of the region.

• International Journal of Industrial Entomology and Biomaterials
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• 제22권2호
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• pp.65-74
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• 2011

The Scarites aterrimus (Coleoptera: Carabidae), is one of the carabid beetles dwelling exclusively on coastal sandy dunes. Habitat deterioration and equivalent activity have greatly concerned population declines in several species dwelling on the coastal sandy dunes. As a first step to establish long-term conservation strategy, we investigated the nation-wide magnitude and nature of genetic diversity of the species. As a first step, we sequenced a portion of mitochondrial COI gene, corresponding to "DNA Barcode" region (658 bp) from a total of 24 S. aterrimus individuals collected over nine sandy dunes belonging to four Korean provinces. The sequence analysis evidenced moderate to low magnitude of sequence diversity compared with other insect species distributed in Korean peninsula (0.152% to 0.912%). The presence of closely related haplotypes and relatively high gene flow estimate collectively suggest that there had been no historical barriers that bolster genetic subdivision. Population decline was postulated on the basis of several missing haplotypes that are well found in the species with a large population size. This interpretation is consistent with field observation of small population size in the coastal sandy dune habitats. The highest genetic diversity estimates were found in the coastal sand dune population of Seogwipo, Jeju Island, justifying a prior attention to the population, in order to sustain overall genetic diversity of the species. Further scrutinized study might be required for further robust conclusion.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.763-766
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• 2008

This study was investigated to the conditions of coastal disaster prevention forests in coastal sand dune in Korea. As a result new planed area were about 250.05ha of 576 sites and average area per site is about 0.43ha. Therefore, it is necessary to readjust it in 1 ha/site for standard of new plan area and 10 ha/year for establishment quantity. In addition, the maintenances methods for about 1,479 ha in the forested area of coastal disaster prevention forest and the basic investigations for forests close to coastal were carried out as soon as possible.

• Journal of Life Science
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• 제18권10호
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• pp.1355-1359
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• 2008

Endophytic fungi predominantly inhabit grasses, and produce a variety of beneficial metabolites for plant growth, as well as help their hosts against pathogens and herbivores. Current study was focused on plant growth promoting activity of endophytic fungi inhabited in the roots of sand dune grasses. We collected 49 fungal isolates from the roots of four most common sand dune grasses and screened them for their growth promoting capacity. Results showed that 37 fungal isolates (75.5%) promoted plant height and shoot length of waito-c rice, 11 fungal isolates (22.5%) suppressed it, while 1 fungus (2%) showed no effect on the growth attributes. The fungal strain Gibberella fujikuroi, along with distilled water and Czapek broth medium, were taken as control for this experiment. It was concluded that a major proportion of endophytic fungi inhabited in the sand dune plants produce metabolites, and thus help in growth and development of the host plant.

• Wind and Structures
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• 제30권4호
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• pp.433-450
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• 2020

The strong turbulence characteristic of typhoon not only will significantly change flow field characteristics surrounding the large-scale wind turbine and aerodynamic force distribution on surface, but also may cause morphological evolution of coast dune and thereby form sand storms. A 5MW horizontal-axis wind turbine in a wind power plant of southeastern coastal areas in China was chosen to investigate the distribution law of additional loads caused by wind-sand coupling movement of coast dune at landing of strong typhoons. Firstly, a mesoscale Weather Research and Forecasting (WRF) mode was introduced in for high spatial resolution simulation of typhoon "Megi". Wind speed profile on the boundary layer of typhoon was gained through fitting based on nonlinear least squares and then it was integrated into the user-defined function (UDF) as an entry condition of small-scaled CFD numerical simulation. On this basis, a synchronous iterative modeling of wind field and sand particle combination was carried out by using a continuous phase and discrete phase. Influencing laws of typhoon and normal wind on moving characteristics of sand particles, equivalent pressure distribution mode of structural surface and characteristics of lift resistance coefficient were compared. Results demonstrated that: Compared with normal wind, mesoscale typhoon intensifies the 3D aerodynamic distribution mode on structural surface of wind turbine significantly. Different from wind loads, sand loads mainly impact on 30° ranges at two sides of the lower windward region on the tower. The ratio between sand loads and wind load reaches 3.937% and the maximum sand pressure coefficient is 0.09. The coupling impact effect of strong typhoon and large sand particles is more significant, in which the resistance coefficient of tower is increased by 9.80% to the maximum extent. The maximum resistance coefficient in typhoon field is 13.79% higher than that in the normal wind field.

• Journal of the Korean Society for Marine Environment & Energy
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• 제19권3호
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• pp.218-226
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• 2016

Field observations were used to study the characteristics and influence of groundwater level fluctuations on vegetation development on the natural beach of a sandy barrier island, in the Nakdong River estuary. The spatial/temporal fluctuations of the groundwater level and the interactions with the external forces (weather, ocean wave and tide) were analyzed. The results indicated that when it rains the groundwater level rises. During summer, when precipitation intensity is greater than 20 mm/hour, it rose rapidly over 20 cm. Subsequently, it fell gradually during periods of no precipitation. Seasonal characteristics indicated that the groundwater level was high during the summer rainy season and tended to fall in the winter dry season. The time-averaged groundwater level, observed from the four observations over 3 years (2012-2014), was about 1.47 m, higher than mean sea level (M.S.L.). It was shown that the average annual groundwater level rises toward the land rather than showing intertidal patterns observation. Differences in the presence or absence of a coastal sand dunes affected the progress of vegetation. In other words, in environments of saltwater intrusion where the groundwater level varies, dependent on the distance from the shoreline and bottom slope, sand dunes can be provided to affect soil conditions and groundwater, so that vegetation can be grown reliably.

• Journal of the Korean Geographical Society
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• 제47권4호
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• pp.474-489
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• 2012

Last review papers on Korean geomorphology and physical geography had been published in 1997 and 2000 respectively. A proposal to publish a book on Korean geomorphologists' achievement resulted in series of review papers in Journal of the Korean Geomorphological Association. This article aims to summarize these papers and introduce their findings to foreign scholars. On remarkable achievement is a fierce debate on the effectiveness of traditional mountain concept to explain the shape of Korean peninsula, which made the public's understanding of geomorphology widen to the general public. Reflecting public demands, concerns for the effects of coastal facilities on coastal erosion and conservation mind and scientific researches for the coastal sand dunes have increased so much. Geomorphological hazards such as debris flow attracted many concerned scientists, and geotourism-related papers in scientific journals increased thanks to the designation of first geopark in Korea. Research papers submitted to the famous foreign academic journals are increasing in numbers these days.

• Journal of Life Science
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• 제20권9호
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• pp.1373-1377
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• 2010

Coastal sand-dune plants can survive very effectively with the help of various microbes, especially ecto- and endomycorrihizae. Penicillium citrinum KACC43900 was screened according to growth promoting activity on sand-dune plants Calystegia soldanella and Ischaemum anthephoroides. In this study, coastal sand-dune plants were treated with a fungal culture filtrate of endophytic fungus P. citrinum KACC43900 to confirm the promotion of plant growth. C. soldanella and I. anthephoroides were used as representative coastal sand-dune plants, and their shoot length, plant length, and dry weight were analyzed. The shoot lengths of control C. soldanella and I. anthephoroides were 8.60 cm and 8.12 cm, and those of samples treated with fungal culture filtrates of C. soldanella and I. anthephoroides for 20 days were 16.30 cm and 10.56 cm, respectively. The plant lengths of control C. soldanella and I. anthephoroides were 14.90 cm and 14.80 cm, and those of samples treated with fungal culture filtrates of C. soldanella and I. anthephoroides for 20 days were 24.06 cm and 17.06 cm, respectively. The dry weight of C. soldanella and I. anthephoroides treated with fungal culture filtrates of C. soldanella and I. anthephoroides for 20 days were 0.163 g and 0.032 g, respectively. It was shown that the growth of shoots in C. soldanella and I. anthephoroides was promoted, 89.54% and 29.60%, by culture filtrate of P. citrinum KACC43900.