• The Korean Journal of Mycology
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• v.41 no.4
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• pp.292-294
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• 2013

In February 2010, the grayish fungus was found on Neofinetia falcata at Namsa-myeon, Yongin city, Gyeonggi-do, Korea. The symptoms start mainly on the leaves and stems, and the infected stems were rotten. Many conidia appeared on the lesions under humid condition. Colonies were grayish brown color and sclerotial formation was observed on potato dextrose agar (PDA). Conidia were mostly ellipsoidal to ovoid in shape, hyaline, one-celled, and $5.3-16.5{\times}3.8-11.0{\mu}m$ in size. Based on morphological characteristics and pathogenicity, the causal fungus was identified as Botrytis cinerea Pers. This is the first report of gray mold on N. falcata caused by B. cinerea in Korea.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.83-89
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• 1999

Butterhead lettuce was grown hydroponically in a plant factory during summer season. To decrease the occurrence of tipburn and increase productivity, optimum cultivars, substrates, gully slope and height, and the amount of irrigation were evaluated in this experiment. Cultivars ‘Rex’ and ‘Flandria’ showed higher productivity with less tipburn as compared to the others in spite of lower growth rates and appeared to be suitable cultivars during summer season. Cocopeat showed high productivity due to superior physio-chemical characteristics. Appropriate gully slope which makes nutrient solution easy to flow was shown to be 1 to 2%. The amount of irrigation was appropriate at 2$\ell$/gully. Higher growth of the butterhead lettuce observed when the bed was at a lower position. Low bed was thought to be good for lettuce growth with proper humidity and average temperatures.

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.117-122
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• 2019

City parks play an important role in reducing the air pollution and mitigating the city heat island effect caused by global warming. However, from July 2020, restricted parks over 20-year will be partially lifted due to sunset regulation on parks. As a result, the government and local governments have been making efforts to revitalize parks, such as creating ecological parks and securing park sites. However, building winds generated by high-rise buildings constructed around ecological parks in the city may cause discomfort to pedestrians and threaten the ecosystems of plants and animal that live in ecological parks. There are no clearly proposed as standards for wind environment assessment in Korea, but also it has been rarely studied on pedestrian wind environment. In this study, wind environment studies have been reviewed to find the important parameters related to wind environment assessment. Further, wind climate analysis using wind data obtained by Seoul meterological station was performed to examine the possibility of applicability of the wind environment assessment on the city ecological parks.

• 한국해양학회지
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• v.12 no.2
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• pp.57-66
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• 1977

Chlorophyll concentrations of phytoplankton were determined by 5 meters interval from surface to bottom layers in Yeongil Bay water of Korea, late October 1973. The contents of phytoplankton chlorophyll decreased outward from the inner part to the entrance of the Bay. It seemed to be caused by incoming land waters which are rich in nutrients. And vertical distribution pattern of the chlorophyll showed three layer zones in the middle and outer parts, and two layers in the inner part of the Bay. These phenomena suggest that there are two different water masses, the one is bottom cold water originated from offshore, the other is surface warm water. And they are mixed together in the middle layer The correlationship between the contents of chlorophyll a and chlorophyll c represented perfect positive relation with coefficient of r 0.999 from the extracted data. In general, chlorophyll a percent-content of total chlorophyll varied in the range of 14.64∼19.83% (mean value; 18.74%) and chlorophyll c content was about as much as four times compared with chlorophyll a content.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.3
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• pp.105-112
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• 2017

Construction and urban development projects that drove urbanization were perceived as a main culprit that disturbs environment and ecosystems, including urban heat island, air pollution and a decrease in species diversity in urban area, as they do not consider natural environment and adopt consistent development behaviors and rapidly degrade the ecology of development sites. In order to build a sustainable green wall system, design process is configured as follows based on basic technology development direction, climate environment elements, climate design technology elements suggested earlier. Each part of required technology element is codified systematically and a sound Korean-style green wall system design direction will be suggested.

• The Korean Journal of Zoology
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• v.32 no.3
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• pp.221-231
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• 1989

The histochemical characteristics of the cutaneous mucous glands and its fine structure of the Korean fire bellied toad, Bombina orientolis Boulenger, were studied with light and electron microscopes. The mucous glands of the toad are simple alveolar gland, and are composed of inner glandular epithelial cells and outermost myoepithelial cells. Histochemical studies suggest that main secretory materials released from the mucous glands might be acid mucopolysaccharides which is more abundant in the ventral skin than in the dorsal skin. The scanning electron microscopic observation showed that the morphology of the opening sites of the gland duct is similar to the morphology of stomata on the plant leaves. Glandular epithelial layers of the mucous glands are composed of two cell types, the mucous secreting cells and the mitochondria rich cells. The mucous secreting cells could be classified according to the morphology and inner textures of cytoplasm and those characteristics were seemed to be related to the degree of maturation of the cells. Furthermore the mucous within the mucous secreting cells appears to be synthesized in the rough endoplasmic reticulum.

• Korean Journal of Environment and Ecology
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• v.23 no.2
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• pp.135-142
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• 2009

To investigate the vegetation structure of mountain ridges ranging from Sebong to Gwaneumbong 23 plots($400m^2$) set up with random sampling method were surveyed. Two groups of Pinus densiflora community, Pinus densiflora-Quercus variabilis-Quercus serrata community were classified by cluster analysis. Pinus densiflora, Quercus variabilis, Quercus serrata, Carpinus laxiflora, and Quecus mongolica were found as a mostly dominant woody plant species in the ridge area from Sebong to Gwaneumbong. In the future, the importance percentage of Pinus densiflora might be decreased, but those of Quercus variabilis, Quercus serrata, Carpinus laxiflora, and Quecus mongolica might be increased. High positive correlations were proved between Quercus variabilis and Fraxinus sieboldiana, Acer palmatum and Ilex macropoda, Cornus kousa and Platycarya strobilacea, Sorbus alnifolia and Carpinus laxiflora, and relatively weak negative correlations were proved between Pinus densiflora and Carpinus laxiflora, Fraxinus sieboldiana and Carpinus laxiflor, Quecus mongolica and Sorbus alnifolia, Ilex macropoda and Sorbus alnifolia. Species diversity index(H') of investigated groups was ranged $0.665{\sim}1.169$.

• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.346-353
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• 2013

Objectives: The goal of this study is to identify the distribution of the foliar fluorine content of vegetation surrounding the area where hydrofluoric acid was accidently released in Gumi, Gyeongsangbuk-do on September 27, 2012. In addition, it also aims to estimate the concentration of hydrogen fluoride in the air on the day of the accident. Methods: Samples of plant leaves were collected on October 7, 2012 within 1 km from the site where the accident occurred. These samples were analyzed for soluble fluorine ion with an ion selective electrode. The ambient concentration of hydrogen fluoride was calculated using the fluoride content in the plant via the dose-rate equation (${\Delta}F$=KCT). Results: The arithmetic and geometric means of the concentrations were 2158.2 and 1183.7mg F $kg^{-1}$ for leaves and, 2.4 and 1.1 ppm HF for the air, respectively. The highest concentration of hydrogen fluoride in the air was 14.7 ppm, which is higher than the maximum concentration reported by the government (1 ppm) and the exposure limit (ceiling, 3 ppm). The concentrations of both fluorine and hydrogen fluoride decreased with increasing distance from the accident site and showed a significant decrease outside of a 500m radius from the site (p <0.05). Conclusions: The area around the accident site was highly polluted with hydrogen fluoride according to the results of this study. Considering the persistency of hydrogen fluoride in the environment, long-term monitoring and environmental impact assessment should be pursued.

• Ocean and Polar Research
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• v.35 no.4
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• pp.415-425
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• 2013

In order to understand phytoplankton and bacterial distribution in tropical coral reef ecosystems in relation to the mangrove community, their biomass and activities were measured in the sea waters of the Chuuk and the Kosrae lagoons located in Micronesia. Chlorophyll a and bacterial abundance showed maximal values in the seawater near the mangrove forests, and then steeply decreased as the distance increased from the mangrove forests, indicating that environmental conditions for these microorganisms changed greatly in lagoon waters. Together with chlorophyll a, abundance of Synechococcus and phototrophic picoeukaryotes and a variety of indicator pigments for dinoflagellates, diatoms, green algae and cryptophytes also showed similar spatial distribution patterns, suggesting that phytoplankton assemblages respond to the environmental gradient by changing community compositions. In addition, primary production and bacterial production were also highest in the bay surrounded by mangrove forest and lowest outside of the lagoon. These results suggest that mangrove waters play an important role in energy production and nutrient cycling in tropical coasts, undoubtedly receiving large inputs of organic matter from shore vegetation such as mangroves. However, the steep decrease of biomass and production of phytoplankton and heterotrophic bacteria within a short distance from the bay to the level of oligotrophic waters indicates that the effect of mangrove waters does not extend far away.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.205-214
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• 2013

In Yeongsan River estuary, located in the southern West Coast, a dike was constructed in December 1981. After the construction of a dike, discharge mechanism of fresh water has been changed, the water quality and chlorophyll-a are expected to be influenced by fresh water discharge. We investigated temporal and spatial variations and long-term trend of phytoplankton biomass (chlorophyll-a) and environmental factors. The concentrations of nutrient and chlorophyll-a were generally high in summer and the concentrations were increased toward downstream. Surface/bottom salinity difference was negatively correlated with salinity in surface water but positively with nutrient and chlorophyll-a. TN, TP and DIN concentrations were generally increased over 10 years. This study can provide information for better management of water quality for Youngsan River estuary.