• Journal of Conservation Science
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• v.34 no.6
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• pp.557-568
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• 2018

The manufacturing techniques were studied by investigating a precise analysis on wall structure, features of materials and the painting layer of the bracket mural paintings at Daeungbojeon Hall in Naesosa temple. The wall frame is a single-branch structure, and The mural paintings are composed of 3 layers which are a support layer, a finishing layer and a painting layer. The support layer and the finishing layer are an earth wall that sand and clay such as Quartz, Feldspar, and etc. are mixed. The support and the finishing layers have a combination of medium particle sand and smaller than fine particle sand in the approximate ratios of 0.8:9.2 and 6:4, respectively. Therefore, the aforementioned ratio of sand with medium or large particles is relatively higher in the finishing layer than the support layer. As a result of a precise analysis on the painting layer, it has a relatively thick ground layer for painting which is maximum $456.15{\mu}m$ by using Celadonite or Glauconite and the paintings were colored by using pigments such as Atacamite, Kaolinite or Halloysite, Oxidized steel, and etc. on it. The manufacturing style and the painting techniques of an earth wall are included in the category of the Joseon Dynasty style that have been studied up to now, but the facts that the finishing layer has a high content of sand and a middle layer and chopped straw have not been identified. These are remarkable points in terms of structure and materials, and can be crucial in the evaluation of the state of conservation of mural paintings or preparation of a conservation plan.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.62-77
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• 2011

Yi Sunsin's artifacts had been exhibited at Hyeonchungsa in Asan-si, Chungchungnam-do. These artifacts include Janggeom(Long swords), Okno(Jade ornament of Korea traditional hat), Yodae(Waist belt) and Dobae(Peach shaped wine cups) Gudae(Yodae's saucers). These were covered with dust and corroded due to long term display. Condition of these artifacts was examined for a re-opening of Yi Chungmugong Memorial Pavilion on 28 March 2011. Before conservation treatment of the artifacts, scientific analysis was conducted to identify the material of the artifacts. The result showed that the red paint on the hilt of the sword is composed of two layers. Pigments of two layers were found to be hematite and cinnabar mixed with red lead respectively. Mixed layer was assumed to have been applied recently. Also it was found that the blade of the sword was repainted using chrome yellow($PbCrO_4$). Considering the time limit, conservation treatment focused on stabilization of damaged area and prevention of futher risk during display.

• Korean Journal of Heritage: History & Science
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• v.49 no.4
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• pp.196-217
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• 2016

This study was conducted to identify the state of conservation of the national paper heritages and to seek ways of conservation management, focusing on regular monitoring directly performed by the government on the national movable cultural heritages. Subjects for the investigation were limited to investigations conducted by both the Cultural Heritage Conservation Center and the Artistic Heritage Division in 2014 and 2015. Paper heritages are easily affected by temperature, humidity, lighting, etc. due to the nature of the material and can easily be damaged by physical strength; therefore stable conservation environment is essential and regular investigation on movable cultural heritages conducted according to the Cultural Heritage Protection Act is necessary to protect from contamination, being torn, bending, friction, or loss. Losing a chance for timely proper treatment will bring irrevocable result therefore strict management is necessary; continuous monitoring is also needed after treatment. Analysis on the pigments, materials and structures, detailed investigation, data establishment for conservation of cultural heritages and regular investigation should be done. Detailed data on the national cultural heritages will be a base of more reasonable conservation management system for the national paper heritages and will realize continuous improvement on regular investigation practice.

• Korean Journal of Ecology and Environment
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• v.52 no.2
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• pp.81-93
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• 2019

Phytoplankton is one of the important primary producers providing organic matter through photosynthesis in aquatic environments. In order to determine a temporal and spatial variation in primary productivity after weir construction in the Nakdong River, we investigated carbon uptake rates using in-situ $^{13}C$ labeling experiments and identified algal communities contributing to primary productivity using HPLC-CHEMTAX analysis from October to December, 2017. The primary productivity gradually decreased from fall to early winter season ($249{\sim}933mgC\;m^{-2}d^{-1}$ in October, $64{\sim}536mgC\;m^{-2}d^{-1}$ in November and $60{\sim}274mgC\;m^{-2}d^{-1}$ in December, respectively). This is attributed to the temporally declining light intensity and the decreasing biomass and physiological activity of phytoplankton in winter. The contribution of diatoms to the phytoplankton community in the Nakdong River was approximately 63% at all the sampling sites and seasons, while the contribution of cryptophytes increased from 9% in October to 32% in November and December. The temporal changes in the primary productivity and the dominant phytoplankton species in the mid and downstream weirs of the Nakdong River was investigated for the first time, after construction of the weirs, and major environmental factors controlling the temporal variation in primary productivity and phytoplankton communities were identified in this study. We suggest that seasonal field investigations will provide further information on the major environmental factors which affect the annual variation of primary productivity and phytoplankton communities.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.351-363
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• 2018

In ornamental crops, the color and shape of flowers are one of the important traits. Generally, flower colors are determined by accumulating pigments such as carotenoids, flavonoids, and betalains. Among them, flavonoids are responsible for broad ranges of colors. Chrysanthemums are one of the most popular ornamental crops in the world, and there have been many efforts to change their flower color. In chrysanthemum flowers, cyanidin-based anthocyanin confers pink or red color, whereas terpenoid-based carotenoids are mainly responsible for yellow and green colors. However, blue colored chrysanthemums do not occur in nature. To date, there have been attempts to obtain blue or violet-colored chrysanthemum flowers through the introduction of a novel gene for accumulating delphinidin-based anthocyanins, while other studies have reported changing endogenous metabolites through the reconstruction of flavonoid biosynthesis. Since various transcription factors are involved in the regulation of flavonoid biosynthesis, it is important to understand not only the structural genes, but also the transcription factors required for the modification of flavonoid-based flower color. Therefore, in this paper, we describe the flavonoid biosynthetic pathway and its regulation, and review previous studies on the change in flower color through modification of flavonoid biosynthesis. This effort could be an important milestone in successfully achieving the modification of chrysanthemum flower color by means of plant biotechnology.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.2
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• pp.100-107
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• 2021

An agrivoltaic system (AVS) is a system of innovation that comprises productions of photovoltaic power and agricultural crops on the same area. However, the decline in crop yield will be fatally occurred because the pigments of crop absorbs less light energy under AVS. In addtion, the photosynthetic capacity of crop grown under the partial shading of AVS is not well reported. In this study, the electron transport rate (ETR) and non-photochemical fluorescence quenching (NPQ) of soybean and rice under the AVS in Boseong and Naju was investigated using chlorophyll fluorescence measurement. The ETR value of soybean and rice under AVS were not significantly differed by location. It represents that the photophosphorylation rate of the crops is not critically different. It means that the decreases in total photosynthesis under AVS were mostly affected by the amount of light absorbed by leaves. Under AVS the photosynthesis of crops will be lower than field crops grown in open fields. This is because the crops under AVS observed higher NPQ, which means that the available energy cannot distribute to photophosphorylation reaction.

• Korean Journal of Environmental Agriculture
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• v.40 no.1
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• pp.49-59
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• 2021

BACKGROUND: Soil salinity causes reduction of crop productivity. Rhizosphere microbes have metabolic capabilities and ability to adaptation of plants to biotic and abiotic stresses. Plant growth-promoting bacteria (PGPB) could play a role as elicitors for inducing tolerance to stresses in plants by affecting resident microorganism in soil. This study was conducted to demonstrate the effect of selected strains on rhizosphere microbial community under salinity stress. METHODS AND RESULTS: The experiments were conducted in tomato plants in pots containing field soil. Bacterial suspension was inoculated into three-week-old tomato plants, one week after inoculation, and -1,000 kPa-balanced salinity stress was imposed. The physiological and biochemical attributes of plant under salt stress were monitored by evaluating pigment, malondialdehyde (MDA), proline, soil pH, electrical conductivity (EC) and ion concentrations. To demonstrate the effect of selected Bacillus strains on rhizosphere microbial community, soil microbial diversity and abundance were evaluated with Illumina MiSeq sequencing, and primer sets of 341F/805R and ITS3/ITS4 were used for bacterial and fungal communities, respectively. As a result, when the bacterial strains were inoculated and then salinity stress was imposed, the inoculation decreases the stress susceptibility including reduction in lipid peroxidation, enhanced pigmentation and proline accumulation which subsequently resulted in better plant growth. However, bacterial inoculations did not affect diversity (observed OTUs, ACE, Chao1 and Shannon) and structure (principle coordinate analysis) of microbial communities under salinity stress. Furthermore, relative abundance in microbial communities had no significant difference between bacterial treated- and untreated-soils under salinity stress. CONCLUSION: Inoculation of Bacillus strains could affect plant responses and soil pH of tomato plants under salinity stress, whereas microbial diversity and abundance had no significant difference by the bacterial treatments. These findings demonstrated that Bacillus strains could alleviate plant's salinity damages by regulating pigments, proline, and MDA contents without significant changes of microbial community in tomato plants, and can be used as effective biostimulators against salinity stress for sustainable agriculture.

• Korean Journal of Remote Sensing
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• v.37 no.4
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• pp.699-717
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• 2021

South Korea is pushing for the advancement of crop production technology to achieve food self-sufficiency and meet the demand for safe food. A medium-sized satellite for agriculture is being launched in 2023 with the aim of collecting and providing information on agriculture, not only in Korea but also in neighboring countries. The satellite is to be equipped with various sensors, though reference data for ground information are lacking. Hyperspectral remote sensing combined with 1st derivative is an efficient tool for the identification of agricultural crops. In our study, we develop a system for hyperspectral analysis of the ground-based reflectance spectrum, which is monitored seven times during the cultivation period of three soybean crops using a PSR-2500 hyperspectral sensor. In the reflection spectrum of soybean canopy, wavelength variations correspond with stages of soybean growths. The spectral reflection characteristics of soybeans can be divided according to growth into the vegetative (V)stage and the reproductive (R)stage. As a result of the first derivative analysis of the spectral reflection characteristics, it is possible to identify the characteristics of each wavelength band. Using our developed monitoring system, we observed that the near-infrared (NIR) variation was largest during the vegetative (V1-V3) stage, followed by a similar variation pattern in the order of red-edge and visible. In the reproductive stage (R1-R8), the effect of the shape and color of the soybean leaf was reflected, and the pattern is different from that in the vegetative (V) stage. At the R1 to R6 stages, the variation in NIR was the largest, and red-edge and green showed similar variation patterns, but red showed little change. In particular, the reflectance characteristics of the R1 stage provides information that could help us distinguish between the three varieties of soybean that were studied. In the R7-R8 stage, close to the harvest period, the red-edge and NIR variation patterns and the visible variation patterns changed. These results are interpreted as a result of the large effects of pigments such as chlorophyll for each of the three soybean varieties, as well as from the formation and color of the leaf and stem. The results obtained in this study provide useful information that helps us to determine the wavelength width and range of the optimal band for monitoring and acquiring vegetation information on crops using satellites and unmanned aerial vehicles (UAVs)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.350-357
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• 2021

In the present study, the seed color of 200 common bean genetic resources was analyzed and located on the HTML color chart to classify these resources according to color characteristics. This classification method predicts the components of seed and may serve as a new method for efficiently using secured genetic resources. The imagary data of common bean exhibiting various seed colors were expressed using the HTML color chart. According to the proposed classification method, the seed color was distributed in seven categories: yellow-green, yellow, brown, red, white, gray, and indigo. In addition, the distribution of each seed color was according to its concentration. The distribution by concentration was the highest for red, whereas the distribution of gray and yellow-green was not concentration-dependent. As the dominant pigments based on color distribution, chlorophylls in yellow-green; carotenoids in yellow; and anthocyanins in brown, red, white, gray, and indigo significantly affected seed color. When expressed objectively, seed colors can be applied to the systematic management, breeding, and cultivation of genetic resources and can be useful for marketing or developing products of desired colors. This method can also be applied to other crops.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.340-354
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• 2021

The aim of this study was to investigate the spatial and temporal distribution of phytoplankton biomass and community composition in Jinhae Bay on the southern coast of Korea. Phytoplankton pigment analysis was conducted using ultra performance liquid chromatography (UPLC) were conducted from April to December 2019 at seven stations. Temperature, salinity, and dissolved oxygen (DO) and inorganic nutrients (dissolved nitrogen, dissolved phosphorus, and orthosilicic acid) were measured to investigate the environmental factors associated with the structure of phytoplankton community. Phytoplankton biomass (Chl-a) was the highest in July (mean 15.4±4.3 ㎍/L) and the lowest in December (mean 3.5±0.6 ㎍/L). Fucoxanthin was the most abundant carotenoid and showed a similar variation pattern to Chl-a, peridinin, and Chl-b. Phytoplankton community composition analysis showed that diatoms were a predominant group with an average abundance of 70 % whereas chlorophytes, cryptophytes, and dinoflagellates often appeared with lower averages. Further, the dominance of diatoms was closely correlated with water temperature and N:P ratio, which might be influenced by high temperatures in the summer and nutrient loading from the land. Additionally, freshwater and nutrient input by rainfall was estimated to be the most important environmental factor. Hence, the spatial and temporal variations in the composition of phytoplankton pigments and phytoplankton community were correlated with physicochemical and environmental parameters.