• Journal of Korea Water Resources Association
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• v.36 no.6
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• pp.893-899
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• 2003

In this study, a realtime bridge scour monitoring system was installed and operated to measure the real scour depths in relatively hard and rocky bottom. And riverbed change at before and after flood was investigated by GPR(Ground Penetrating Radar) to check the rationality of measured values. As the result of this study, it was revealed the inaccuracy of equilibrium scour depth estimation through the bridge scout equations because most of the equations do not reflect the differences of geological characteristics, evaluated the real scour depths considering both bed and flow conditions.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.311-316
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• 2012

Fusarium root disease can be a serious problem in forest and conservation nurseries in the western United States. Fusarium inoculum is commonly found in most container and bareroot nurseries on healthy and diseased seedlings, in nursery soils, and on conifer seeds. Fusarium spp. within the F. oxysporum species complex have been recognized as pathogens for more than a century, but attempts to distinguish virulence by correlating morphological characteristics with results of pathogenicity tests were unsuccessful. Recent molecular characterization and pathogenicity tests, however, revealed that selected isolates of F. oxysporum are benign on Douglas-fir (Pseudotsuga menziesii) seedlings. Other morphologically indistinguishable isolates, which can be virulent, were identified as F. commune, a recently described species. In a replicated greenhouse study, inoculating Douglas-fir seedlings with one isolate of F. oxysporum prevented expression of disease caused by a virulent isolate of F. commune. Moreover, seedling survival and growth was unaffected by the presence of the F. oxysporum isolate, and this isolate yielded better biological control than a commercial formulation of Bacillus subtilis. These results demonstrate that an isolate of nonpathogenic F. oxysporum can effectively reduce Fusarium root disease of Douglas-fir caused by F. commune under nursery settings, and this biological control approach has potential for further development.

• ALGAE
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• v.27 no.4
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• pp.269-281
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• 2012

Marado is a small rocky island located off the south coast of Jeju Island and acts as the first gateway of the Kuroshio Current to Korean coastal ecosystems. This island is one of the most unpolluted and well preserved sea areas around the Jeju coast. We extensively observed macroalgal assemblages of species and functional forms in the intertidal and subtidal zones through four seasons on Marado, Jeju Island, Korea to demonstrate the seasonality of vertical distribution patterns and biomass. A total of 144 species (14 Chlorophyta, 40 Phaeophyta, and 90 Rhodophyta) were identified in quadrats and were analyzed seasonally and vertically to define the variation patterns. The annual mean biomass of macroalgae was $2,932.3g\;wet\;wt\;m^{-2}$ and the highest value was recorded in spring and the lowest was in winter. The annual dominant species by biomass was Ecklonia cava followed by Sargassum fusiforme, S. macrocarpum, Amphiroa galapagensis, Chondria crassicaulis, and S. thunbergii. Obvious biomass zonation patterns of macroalgal species were detected in relation to tidal height and depth. Macroalgal biomass, diversity index (H'), and community dynamics were the highest in the shallow subtidal zone. Species number was higher in the subtidal than in the intertidal zone and similar throughout the entire subtidal zone. Our results provide revealing insights into the distribution patterns of macroalgal assemblages in an unpolluted sea area around Jeju Island.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.13 no.2
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• pp.207-221
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• 2002

Wolaksan is a national park which has beautiful scenery with exposed rocks. The mountain is 1097 meters high and has 3 tops which are Jungang(the center), Arae(the lower part), Jjokduri. The highest point of the vertical cliff is 150m from the earth and the total circumferences of three tops is about 4km. These tops are easy to break by grains because they are from sedimentary rocks. Wolaksan is a bad mountain because the area is a Mosikjuk rocky area. However, the area around Wolaksan is thicky wooded and has many achievements and it makes good scenery. From top to southeastern, there are vertical cliff, The tops are originally from one but these are divided by partial weathering corrosion. The slide of path to Wolaksan is about 70。. The lower part of the mountain from Shinroksa to top has a gentle slope but there are a steep slope from the middle. Especially, the area has many rocks. The rocks of Wolaksan are almost granitic-gneiss or metamorphic rocks so it often fall down. Because of these fallen rocks, its valleys have great landscapes. The size of rock is less than 60cm. The landscapes of valleys such as Songgye, Dukju, Yonghwa are the main natural tourism resources.

• Journal of Korean Society of Forest Science
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• v.94 no.2 s.159
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• pp.117-120
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• 2005

This study was conducted to estimate population size and investigate habitat characteristics for the conservation and management of Amur goral Nemorhaedus caudatus raddeanus in DMZ (Demilitarized Zone) of Gangwon Province in South Korea from November 2003 to May 2004. The Amur gorals counting were carried out by assistance of military soldiers who guards the southern boundary of DMZ. Four hundred sixty individuals were estimated as total population size in DMZ of Gangwon Province. Deciduous forest, rocky area and coniferous forest were dominant land cover types in habitat of Amur goral. DMZ and its vicinity of Gangwon Province are very important areas for the conservation of this species. It is needed to establish management plan for the conservation of Amur goral and their habitats in DMZ.

• Korean Journal of Ichthyology
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• v.12 no.1
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• pp.20-24
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• 2000

The blenniid fish, Istiblennius dussumieri (Valenciennes) was reported on the basis of six specimens collected from rocky shores on the Yokonami Peninsula, Kochi Prefecture, southern Japan. This species was characterized by wavy, dusky stripes on its dorsal fin, 14 pectoral fin rays, 38 to 42 vertebrae, branched supraorbital cirrus, finger-like nasal cirrus, seven to ten vertical, dark bands on the body and canines absent on both jaws. Although the occurrence of this species may be due to larval transport by the Kuroshio Current, this is the first record of I. dussumieri from Japan represents a remarkable northern range extension of the species in the western Pacific Ocean.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.149-162
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• 2004

This study was performed to evaluate the effect of freeze-dried bone graft on space-making capacity and bone formation in the procedure of guided bone regeneration with titanium reinforced ePTFE membrane. After decortication in the calvaria, GBR procedure was performed on 8 rabbits with titanium reinforced ePTFE membrane filled with human FDBA(Rocky Mountain Tissue Bank,Aurora Co., USA). Decortication was performed to induce the effect of bone forming factor from bone marrow. The animals were sacrificed at 2 weeks, 4 weeks, 8 weeks and 12 weeks after the surgery. Non-decalcified specimens were processed for histologic analysis. πle results of this study were as follows: 1. Titanium reinforced-ePTFE membrane was biocompatable and capable of maintaining the space-making. 2. FDBA particle was surrounded with connective tissues but there was no evidence on new bone formation. 3. FDBA particle resorbed continuously but it remained until 12weeks after the surgery. Within the above results, TR-ePTFE membrane could be used effectively for Guided bone regeneration but It was assumed that FDBA does not appear to contribute to bone formation.

• ALGAE
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• v.31 no.1
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• pp.41-48
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• 2016

The clonal seaweed Chondrus crispus (Rhodophyta, Gigartinales) forms extensive stands at low intertidal elevations on wave-sheltered rocky shores of the North Atlantic. This study investigates if this bushy alga acts as a foundation species in such habitats. The abundance (percent cover) of C. crispus, all other algae, and invertebrates was measured in 390 quadrats spanning 350 km of coast in Nova Scotia, Canada. In these low-intertidal habitats, fucoid algae are the largest organisms and can form extensive canopies, but their cover was unrelated to benthic species richness and to C. crispus cover. Species richness, however, increased with C. crispus cover from low to intermediate cover values, showing little change towards full C. crispus cover. Species composition (a combined measure of species identity and their relative abundance) differed between quadrats with low (0-1%) and high (60-100%) cover of C. crispus. High C. crispus cover was associated to more invertebrate species but fewer algal species than low C. crispus cover. However, the average abundance of algal and invertebrate species occurring in both cover groups was often higher under high C. crispus cover, contributing to a higher average richness at the quadrat scale. Overall, only 16% of the observed variation in species richness was explained by C. crispus cover. Therefore, this study suggests that C. crispus acts as a foundation species but with a moderate influence.

• ALGAE
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• v.22 no.3
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• pp.209-219
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• 2007

Marine algal flora and community structure of medicinal seaweeds were examined at Kkotji of Taean Peninsula, Korea from May 2005 to January 2006. Seventy-nine seaweeds including 42 medicinal algae and one marine plant were identified. Sargassum thunbergii was the representative alga occurred at all seasons and shore levels. The dominant medicinal seaweeds were perennial S. thunbergii, Neorhodomela aculeata, and Corallina pilulifera, and ephemeral Monostroma grevillei, Porphyra yezoensis, and Ulva pertusa. Their vertical distribution were N. aculeata – P. yezoensis, M. grevillei, and U. pertusa – C. pilulifera from high to low intertidal zone. The average biomass of medicinal seaweeds varied from 34.17 g m–2 in spring to 56.41 g m–2 in summer. At Kkotji shore, the opportunistic species (Enteromorpha, Ulva, and Cladophora) and turf-forming algae (Caulacanthus okamurae and Gelidium divaricatum) were easily observed. Such fast growing ESG II (ecological state group) was 87.50% and slow growing perennial algae, ESG I was only 12.15%. Also, diversity index (H’) and dominance index (DI) indicate that the seaweed community of Kkotji is unstable. Therefore, Kkotji rocky shore should be more protected from human activities such as turbulence and eutrophication in order to maintain species diversity and abundance of medicinal seaweeds.

• The Korean Journal of Malacology
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• v.24 no.3
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• pp.199-203
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• 2008

Thirty one marine molluscan species were added to the malacofauna of Dokdo Island, Korea based on the samples collected from April 2006 to August 2008 with SCUBA diving. As a result, one hundred six marine molluscan species were recorded from Dokdo Island hitherto.