• Animal Systematics, Evolution and Diversity
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• v.31 no.1
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• pp.42-45
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• 2015

A tri-spine horseshoe crab, Tachypleus tridentatus (Leach, 1819) was collected from a sandy beach of Udo Island of Jeju during the full moon tides in November 1997. Three spines on the posterior margin of the opisthosoma were characterized indicating that the specimen was T. tridentatus. This specimen was a female with the total length of 49.5 cm and prosoma width of 23.0 cm. Tachypleus tridentatus was the first record from Korean waters. A brief description and figures of the species were given. This finding indicates that Korea is included to the distribution range of the species.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5D
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• pp.655-662
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• 2009

The monitoring for analyzing coastline variations throughout many years is conducted in this study. Haeundae Beach is selected as a test area. We have collected RTK-GPS survey data, airborne LiDAR survey data from Sept. 2008 to 2005. We've done airborne LiDAR survey 2009 to 2006 and we would analyze coastline changes time series through interactive comparison analysis. The mean coastline distance of Haeundae shore is 1,347m (RTK-GPS) by airborne LiDAR survey (2 times). Coastline distance is decreased approximately 4.5% than mean distance in the November survey of 2008. We know right and left sides of the coastline are eroded and the center section shows us the littoral deposit of 3~7m toward sea. It turns out that the sand both sides is transported to the center section by a wave and tide and we know the coastline distance is getting smaller but the coastline width is getting longer like 2~7m.

• Korean Journal of Environment and Ecology
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• v.12 no.1
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• pp.91-101
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• 1998

Two large communities of Vicex rotundifolia were discovered for the first time at the beach of Pyonsanbando National Park. The growth environment and morphological characters of the communities were examined and analyzed to provide some basal data which would be helpful to establish measures for protection and to utilize the communities rationally. The results are as follows; The habitats of Vitex rotundifolia are located at Chakeundang beach of Kyokpo-ri and Kosapo beach of Woonsan-ni, Pyonsan-myon in Pyonsanbando National Park. The total area of this two communities was measured to be 2,755m$^{2}$ and 523m$^{2}$ of it was damaged. Two varieties, 49 species, 43 genera and 28 families as trees and shrubs were collected from inside of and the vicinal areas of the communities. Koelreuteria paniculata and Rosa rugosa were discovered and collected in these areas for the first time to be documented with the communities of Vitex rotundifolia. The largest individual of Vitex rotundifolia within the polulations reaches or 3.5cm in diameter at root collar and 6m in length of the runner on aboveground. The individuals of Vitex rotundifolia within the communities show good growth condition which the mean leaf length was measured to be 4.5cm, the mean leaf width 3.3cm, the mean leaf area 11.8cm$^{2}$ and the mean flower length 10.0cm. Vitex rotundifolia has been mostly recorded to be an evergreen shrub. But the present study discovered that it is rather deciduous.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.365-375
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• 2009

The growth characteristics of Pinus thunbergii windbreak forest around Goosipo Beach, Sangha-Myon, Gochang-Gun, Jeollabuk-Do have been investigated, and the results are summarized as follows. The soil in the site was light acid sand with pH 5.7, and the mean sodium concentration of soils was 1.42dS/m. The tree diameter, height, crown width, and shape ratio(Height/DBH) were better with tree density was coming lower. Especially, the rate of shape ratio under 60 was more in sites with low tree density. This demonstrated that the trees have grown more soundly when the tree density was lower. The direction of main winds and distribution ratio of tree inclination had a correlation. The inclined trees are seemed to be influenced by main winds when they were younger and by Typhoon partly. Eighty one vascular plant species were found in the sites, and more number of herbaceous plants (57 taxa) lived there than woody plants (24 taxa). And more plant species of dune were found at the site where dune have developed well. Some thinning works need at high tree density areas in order to ensure effects of coastal windbreak.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.2
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• pp.186-195
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• 2005

Topography of beach line is keeping stability for several years, their soil values have been maintained in balances. Install of coastal structures have caused deformation for beaches and acted as a function to structures. Therefore, quantitative prediction of beaches topography according to structure install is required to prevent the beaches deformation and progress proper coastal preservation work. In this study, we analyzed coastal changes caused by erosion and accretion according to development and drew up a cross-section to share 8 stations using coordinates and depth surveying in groin of Soheuksan island port. Elevation distribution and changes by observation period is calculated -0.30m~+0.20m after comparing results of five months in October 7, 2004 surveying results and fell into insignificance. We thinks periodic observation of coastal erosion and accretion take place for the season and long-term coastal changes in beaches width is analyzed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4B
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• pp.421-428
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• 2008

For last decades, the rapid coastal erosion process spreading along Korean peninsular has become a nuisance especially for tourism and local economy. Global warming and sea-level rise demand persistently new coastal protection strategies against the conventional methods using armored structures. In a view of this, Kweon et al. (2007) has proposed a new type of horizontal steel plates for an ideal candidate as eco-friendly detached breakwater systems for global warming era. The breakwater is composed of piles and horizontal porous plates that was devised for the optimized blockage effects and wave energy dissipations. This system provides outstanding performances as wave barrier and added advantages such as a rapid installation, an easy relocation, a perfect water circulation for the stagnation of pollutions in sheltered regions. The present experimental study focuses on the performance evaluations of the proposed system in wind wave conditions as a wave dissipator and reflector. The reflection, transmission, and energy dissipation of the random waves has been discussed in detail based on a newly proposed relation between wave steepness and a plate width normalized by wave length that are major factors affecting the wave transmission.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.319-328
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• 1997

To develop a beneficial microbial feed for the cultivation of rotifer, Brachionus plicatilis, an aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ was isolated from marine structure at Haeundae beach in Pusan, Korea. Feeding effects of Erythrobacter sp. $S\;\pi-I$ on the growth of rotifer were analyzed comparing to other feeds such as PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. Erythrobacter sp. $S\;\pi-I$ contained more linoleic acid $(C_{18:3\omega3})$ and oleic acid $(C_{18:1\omega9})$ and amino acids than PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. The rotifer fed on Erythrobacter sp. $S\;\pi-I$ showed better effects than those fed on other feeds in the individual growth, size and weight. Also, the rotifer especially contained more eicosapentaenoic acid $(C_{20:5\omega3})$ and docosahexaenoic acid $(C_{22:6\omega3})$ in case of Erythrobacter sp. $S\;\pi-I$ feeding than the other feeds. In case of the feed of PSB and baker's yeast docosahexaenoic acid $(C_{22:6\omega3})$ did not show. In amino acid analysis, the rotifer fed on Erthrobacter sp, $S\;\pi-I$ showed more amino acid content comparing to those fed on other diets. Especially, arginine, isoleucine, histidine, lysine, methionine, phenylalanine, threonine, which are essential amino acid for fish growth, showed high contents. These results suggested that the aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ would be a beneficial microbial teed for the cultivation of rotifer.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.237-237
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• 2015

The district of Marlborough has had more than its share of river management projects over the past 150 years, each one uniquely affecting the geomorphology and flood hazard of the Wairau Plains. A major early project was to block the Opawa distributary channel at Conders Bend. The Opawa distributary channel took a third and more of Wairau River floodwaters and was a major increasing threat to Blenheim. The blocking of the Opawa required the Wairau and Lower Wairau rivers to carry greater flood flows more often. Consequently the Lower Wairau River was breaking out of its stopbanks approximately every seven years. The idea of diverting flood waters at Tuamarina by providing a direct diversion to the sea through the beach ridges was conceptualised back around the 1920s however, limits on resources and machinery meant the mission of excavating this diversion didn't become feasible until the 1960s. In 1964 a 10 m wide pilot channel was cut from the sea to Tuamarina with an initial capacity of $700m^3/s$. It was expected that floods would eventually scour this 'Wairau Diversion' to its design channel width of 150 m. This did take many more years than initially thought but after approximately 50 years with a little mechanical assistance the Wairau Diversion reached an adequate capacity. Using the power of the river to erode the channel out to its design width and depth was a brilliant idea that saved many thousands of dollars in construction costs and it is somewhat ironic that it is that very same concept that is now being used to deal with the aggradation problem that the Wairau Diversion has caused. The introduction of the Wairau Diversion did provide some flood relief to the lower reaches of the river but unfortunately as the Diversion channel was eroding and enlarging the Lower Wairau River was aggrading and reducing in capacity due to its inability to pass its sediment load with reduced flood flows. It is estimated that approximately $2,000,000m^3$ of sediment was deposited on the bed of the Lower Wairau River in the time between the Diversion's introduction in 1964 and 2010, raising the Lower Wairau's bed upwards of 1.5m in some locations. A numerical morphological model (MIKE-11 ST) was used to assess a number of options which led to the decision and resource consent to construct an erodible (fuse plug) bank at the head of the Wairau Diversion to divert more frequent scouring-flows ($+400m^3/s$)down the Lower Wairau River. Full control gates were ruled out on the grounds of expense. The initial construction of the erodible bank followed in late 2009 with the bank's level at the fuse location set to overtop and begin washing out at a combined Wairau flow of $1,400m^3/s$ which avoids berm flooding in the Lower Wairau. In the three years since the erodible bank was first constructed the Wairau River has sustained 14 events with recorded flows at Tuamarina above $1,000m^3/s$ and three of events in excess of $2,500m^3/s$. These freshes and floods have resulted in washout and rebuild of the erodible bank eight times with a combined rebuild expenditure of $80,000. Marlborough District Council's Rivers & Drainage Department maintains a regular monitoring program for the bed of the Lower Wairau River, which consists of recurrently surveying a series of standard cross sections and estimating the mean bed level (MBL) at each section as well as an overall MBL change over time. A survey was carried out just prior to the installation of the erodible bank and another survey was carried out earlier this year. The results from this latest survey show for the first time since construction of the Wairau Diversion the Lower Wairau River is enlarging. It is estimated that the entire bed of the Lower Wairau has eroded down by an overall average of 60 mm since the introduction of the erodible bank which equates to a total volume of $260,000m^3$. At a cost of $$0.30/m^3$ this represents excellent value compared to mechanical dredging which would likely be in excess of $$10/m^3$. This confirms that the idea of using the river to enlarge the channel is again working for the Wairau River system and that in time nature's "excavator" will provide a channel capacity that will continue to meet design requirements.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.90-102
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• 2012

Sansuyucheop by Heojoobugun(虛舟府君) as the subject of this study is a 십이-width picture album by the eldest grandson of 11 generations for Goseong Lee family, Lee Jong Ak(李宗岳: 1726-1773), a figure having five habits(五癖) for ancient documents(古書癖), playing the gayageum(彈琴癖), flowering plant(花卉癖), paintings and calligraphic works(書畵癖) and boating(舟遊癖) etc., who boated with 18 relatives, and those by marriage from old home, home of mother's side, wife's home, and his home for 5 days Apr. 4 through 8, 1763, starting from Imcheonggak, through Yangjeong(羊汀), Chiltan(七灘), Sabin Auditorium(泗濱書院), Seonchang(船倉), Nakyeon(落淵), Seonchal(仙刹), Seonyujeong(仙遊亭), Mongseongak(夢仙閣), Baekwoonjeong(白雲亭) and Naeap Village(川前里), Iho(伊湖), Seoeodae(鮮魚帶) to the returning point, Bangujeong(伴鷗亭), cruised magnificent views around Banbyeoncheon called 'Andong 8 Gyeong' or 'Imhagugok', and whenever the boat anchored, appreciated the scenery at each point, and enjoyed and loved arts playing the geomungo. This study reached following findings through grasping physical, ecological, visual and aesthetic changes about the places, sceneries, plant elements and past and current scenery of the width pictures expressed at this Sansuyucheop. The refinement on the boat seeing the clear river water, white sand beach, fantastically-shaped cliffs expressed at this Sansuyucheop, exchanging poems and calligraphies, and enjoying the geomungo is a good example displaying the play culture of high-class in Joseon Dynasty. Also construction of Imha Dam and Andong Dam has caused serious visual and ecological changes, making us not enable to feel the original mood of the background spots such as Yangjeonggwabeom(羊汀過帆), Chiltanhuseon(七灘候船), Sasubeomjoo(泗水泛舟), Seonchanggyeram(船倉繫纜), Nakyeonmosaek(落淵莫色), Mangcheonguido(輞川歸棹), Ihojeongdo(伊湖停棹), but only discern then landscape or sentiment through the landscape described at the canvas. The 1st picture(Donghohaeram, 東湖解纜), and the 11th picture(Seoeobanjo, 鮮魚返照) of Heojoobugun's Sansuyucheop expressed trees thought to be fallen, brad-leaf tall trees, and the 9th picture(Unjeongpungbeom, 雲亭風帆) formed a pine forest called 'Gaeho(開湖)' by Uncheongong planting 1,000 pine trees with the village people in 1617. In addition, Seunggyeongdo expressed ever-green needle leaf trees at the natural topography, and fallen-leaf tall trees around the pavilion and building. Comparative consideration of Heojoobugun's Sansuyucheop and Shinam's Dongyusipsogi(東遊十小記) showed that the location of Samgok is assumed to be Macheon and Chiltan, so Imhagugok is assumed to start from Baekunjeong of Ilgok, Igok from Imcheon and Imcheon auditorium, Samgok from Mangcheon and Chiltan, Sagok from Sabin Auditorium of Sasoo, Ogok from Songseok, Yukgok from Sooseok of Seonchang, Chilgok from Nakyeonhyeonryu, Palgok from Seonchalsa and Seonyoojeong, and Gugok from Pyong Yuheo. This study can be significant in that it could clarify that Heojoobugun's Sansuyucheop is judged to be valuable in exquisitively expressing the coast of Banbyeon River, the biggest branch stream in the Nakdong River at the latter half of Joseon Dynasty, and as a vital diagrammatical historical data to make a comparative analysis of currently rarely-seen ancestors' life traces and landscape factors with present ones.