• Asian Journal of Atmospheric Environment
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• v.7 no.1
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• pp.17-24
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• 2013

Fog deposition onto the cool-temperate deciduous forest around Lake Mashu in northern Japan was estimated by the inferential method using the parameterizations of deposition velocity and liquid water content of fog (LWC). Two parameterizations of fog deposition velocity derived from field experiments in Europe and numerical simulations using a detailed multi-layer atmosphere-vegetation-soil model were tested. The empirical function between horizontal visibility (VIS) and LWC was applied to produce hourly LWC as an input data for the inferential method. Weekly mean LWC computed from VIS had a good correlation with LWC sampled by an active string-fog collector. By considering the enhancement of fog deposition due to the edge effect, fog deposition calculated by the inferential method using two parameterizations of deposition velocity agreed with that computed from throughfall data. The results indicated that the inferential method using the current parameterizations of deposition velocity and LWC can provide a rough estimation of water input due to fog deposition onto cool-temperature deciduous forests. Limitations of current parameterizations of deposition velocity related to wind speed, evaporation loss of rain and fog droplets intercepted by tree canopies, and leaf area index were discussed.

• Natural Product Sciences
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• v.25 no.4
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• pp.354-357
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• 2019

Toxicodendron vernicifluum, also called as Rhus verniciflua is a deciduous tree belonging to Anacardiaceae family. Two new caffeoyl threonate esters, rhuseols A (1) and B (2), together with 5-O-(E)-caffeoylquinic acid methyl ester (3) were isolated from the leaves of T. vernicifluum. The structures of isolated compounds were established by using 1D and 2D NMR in combination with HR-ESI-MS. Compounds 1 - 3 showed DPPH radical scavenging effects with IC₅₀ values of 47.9, 107.8 and 15.4 μM, respectively. Taken together, these compounds might contribute to the antioxidant properties of the leaves of T. vernicifluum, which will be useful for various oxidative stress mediated diseases.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.193-200
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• 2008

We obtained quantitative information on leaf unfolding and leaf shedding by observing 45 species of cool temperate deciduous trees in an arboretum over 5 growing seasons. These trees were in leaf (the foliage period) for 207 days on average after 1 April; 50% of leaves had been shed by 192 days after 1 April. Duration from the start of leaf unfolding to 50% leaf shedding was 157 days on average. Leaf unfolding began 35 days on average after 1 April. For leaf unfolding to begin, a$ 51^{\circ}C{\cdot}day$ of cumulated daily mean air temperature above $5^{\circ}C$ from 1 January (modified Kira's warmth index) was needed. Fifty-nine days elapsed between initiation and the final stage of leaf unfolding. The period of net photosynthetic assimilation was 157 days. The species with succeeding- type leaf unfolding associated with the anemochore seed type dominated the early stage of succession, while the species with flush-type leaf unfolding tended to dominate the late stage of succession. Few species were found in regions where late frosts occur after the day when the cumulative temperature for leaf unfolding is achieved. Biological characteristics include time of leaf unfolding, which affects the life history of each species, so that each species occupies its own niche in the stand. We conclude that that leaf phenology, such as timing of leaf unfolding and leaf shedding, is one of the components of each species' ecological characteristics.

• Korean Journal of Ecology and Environment
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• v.51 no.4
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• pp.259-267
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• 2018

This study was conducted to confirm phenological response of main deciduous woody species in Korea according to elevated temperature. Based on seeds collected from the same place, 39 woody species were cultivated in field (control) and in greenhouse (treatment) that was maintained above base temperature ($4.8^{\circ}C$). And then, we observed phenotype change of leaves focused on phenological response and explained relation with their current distribution area. As a result, initiation period of leaves unfolding was 1st~3rd, May in control. It was 13, December~7, January in treatment. Period of leaves yellowing was 11~26, October in control. It was 30, October~13, November in treatment. Consequently, initiation period of leaves unfolding was faster by 119~140 days and period of leaves yellowing was slower by 3~32 days since elevated temperature. Period of leaves growth increased in treatment by 148 days than control. Quercus mongolica and Quercus serrata that cultivated in treatment was changed as evergreen trees which have grown up continuely during one year. Also, initiation period of leaves unfolding of Sorbus alnifolia in treatment was faster than in control. However, difference of the period between control and treatment was smallest. Because period of yellowing leaves was moved ahead. Phenological response of leaves according to elevated temperature had no relation of type of their current distribution area. This is the result of acclimation due to elevated temperature during the winter and suggests that the phenotype of leaves of 39 deciduous woody species is more sensitive to the current growth condition than to the past growth condition.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.725-728
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• 1998

Phytophthora crown rot of cymbidium was observed in Cheju island since June of 1996. The disease initiated at the basal portion of infected plant progressed upward to lower leaves. Soon after distinct water-soaking lesions appeared on lower leaves, the plant was wilted, blighted and died. Four orchid farms at Sogwipo out of 16 surveyed in the island were infected by the disease estimating 5~20% infection rates. The causal fungus was identified as P. palmivora based on following distinguishing characteristics. All isolates were heterothallic as A1 types and readily produced chlamydospores with cultural age. Sporangia were conspicuous papillate, ellipsoidal to ovoid, highly deciduous with short pedicels ca. 3~4 ${\mu}{\textrm}{m}$. Koch's rules were satisfied by a pathogenicity test and re-isolation of the fungus from inoculated plants. The pathogen has never been reported in Cheju island previously and its firstly recorded as the cause of Phytophthora crown rot of cymbidium in Korea.

• YAKHAK HOEJI
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• v.1 no.1
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• pp.2-4
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• 1948

Syringa oblata var dilatata (Nakai) Rehder is a oleaceous, deciduous shrub indigenous in the calcareous zones of Korea. The author researched the constituents of the leaves of the plant, especially the bitter principles which may be used as amara. According to the literature a bitter principle Syringin and Mannitol were isolated from the leaves of S. vulgaris L. And later on B. Power indicated that syringin and mannitol were widely distributed in oleaceous plants. The fresh leaves of the plant wer extracted with hot water, the filtered clear liquid was mixed with solution of lead acetate. The lead precipitate was filtered off and the filtered liquid was freed from lead by H$_{4}$S. The filtrate thus obtained was evaporated, and from the residue colorless needles, M. P. 166.deg., were obtained. It was soluble in water, in hot alcohol, and insoluble in ether and had a sweet taste. The results of the elementar analysis, M. P. and other characteristics agreed with that of d-mannitol. Finally it was proved to be identical with d-mannitol through conversion of it into Hexaacetyl mannitol, M. P. 124.deg., Triformal mannitol, M. P. 227.deg., Tribenzal mannitol, M. P. 224.deg., which exhibited no depression, when mixed with authentic specimens. The experiments to isolate bitter principles of the plant are in progress.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.86-86
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• 2020

The leaves of Staphylea bumalda (S. bumalda) as a deciduous tree distributed in Korea, China and Japan are used to treat respiratory diseases or inflammation. However, there is no scientific research on the immune-enhancing activity of S. bumalda leaves. Thus, in this study, we investigated the effect of water extracts from S. bumalda leaves (SBL) on the macrophage activity using mouse macrophage cells, RAW264.7. SBL increased production of immunomodulators such as NO, iNOS, IL-1β, IL-6, TNF-α and MCP-1 in RAW264.7 cells and activated phagocytic activity of RAW264.7 cells. Inhibition of TLR2 and TLR4 blocked SBL-mediated production of immunomodulators in RAW264.7 cells. In addition, SBL-mediated production of immunomodulators was attenuated by JNK inhibition in RAW264.7 cells. SBL increased JNK phosphorylation, while Inhibition of TLR2 and TLR4 blocked SBL-mediated JNK phosphorylation in RAW264.7 cells. These results are thought to be evidence that SBL activates JNK through stimulation of TLR2 and TLR4 in macrophage to induce the production of immunomodulators. In LPS-stimulated RAW264.7 cells, SBL inhibited over-production of immunomodulators. Summarizing the results, SBL showed immunostimulatory activity under normal conditions and immunosuppressive activity under LPS-induced excessive immune response conditions.

• Proceedings of the Microbiological Society of Korea Conference
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• 2002.10a
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• pp.100-105
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• 2002

The diversity of epiphytic bacterial communities on deciduous oak tree (Quercus dentate Thunb.) leaves was examined both in the natural forest area with a clean air and in the industrial estate to assess effects of acidic deposition to the phyllosphere using 16S rDNA sequence data. In addition, acid-tolerant epiphytic bacterial communities were compared. A total of 78 epiphytic and 444 acid-tolerant clones were obtained from clone libraries, resulting in 20 and 17 phylotypes by analysis of restriction fragment length polymorphism (RFLP) for PCR-amplified 16S rDNA products. A low bacterial diversity in both areas was found. As tree leaves grow older, bacterial diversities were slightly increased in the level of subphylum. The community structure of epiphytic bacteria in both areas in April consisted of only two subphyla, $\beta-and\;\gamma-Proteobacteria$. In August two additional subphyla in both areas were found, but the composition was a little different, Acidobacteria and Cytophaga-Flexibacter-Bacteroids (CFB) group in the industrial estate and a -Proteobacteria and CFB group in the natural area, respectively. Acidobacteria could be an indicator of epiphytic bacteria for acidic deposition on plant leaves, whereas a -Proteobacteria be one of epiphytic bacteria that naturally survive on leaves that are not affected by acidic deposition. The acid-tolerant bacterial communities in April were composed of two subphyla, $\gamma-Proteobacteria$ and Low G+C gram-positive bacteria in both areas, and in August a-Proteobacteria was added to the community just in the natural forest area. The direct influence of acidic deposition on the acid-tolerant bacterial phylogenetic composition could not be detected in higher taxonomic levels such as subphylum, but at narrower or finer levels it could be observed by a detection of Xanthomonadales group of $\gamma-Proteobacteria$ just in the industrial estate.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.123-128
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• 2003

This study was conducted to examine the water use efficiency (WUE) in five species of one-year-old seedlings grown in a field nursery in Mongolia. Larix sibirica and Pinus sylvestris are the most dominant coniferous species while Ulmus pumila is an important deciduous species known well-adapted in harsh conditions such as in semi-arid forests and Gobi desert regions. Caragana arborescens (Siberian pea shrub) and Hippophae rhamnoides are N-fixing shrubs in Mongolia. Thirty one-year-old seedlings were sampled from each of the five species (a total of 150 samples) and measured for net photosynthetic rate (Pn) and transpiration rate (E). The Pn and E were used to calculate and compare the WUE of each species. Pn differed significantly among the five species (p < 0.05). However, there was no significant difference in Pn between L. sibirica and H. rhamnoides (p > 0.05). C. arborescens showed the highest Pn whereas U. pumila did the poorest. E differed significantly among the five species (p < 0.05). L. sibirica and U. pumila showed considerably lower E than other species. Thus, WUE values of coniferous species such as L. sibirica and P. sylvestris were significantly greater than deciduous or shrub species such as U. pumila, C. arborescens and H. rhamnoides (p < 0.01). It may result that conifers showed relatively high water use efficiency than deciduous or shrub trees due to their lower transpiration rates, which resulted in morphological and physiological characteristics of their leaves. This may indicate that L. sibirica and P. sylvestris can be widely used for rehabilitation works in Mongolia attributed to their dominant distributions but also their high drought-resistance properties.

• Asian Journal of Atmospheric Environment
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• v.7 no.1
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• pp.8-16
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• 2013

The fog water chemistry and deposition in northern Japan were investigated by fog water and throughfall measurements in 2010. Fog water was sampled weekly by an active-string fog sampler at Lake Mashu from May to November. Throughfall measurements were conducted using rain gauges under three deciduous trees along the somma of the lake from August to October. The mean fog deposition rate (flux) was calculated using throughfall data to estimate the total fog water deposition amount for the entire sampling period. $NH_4{^+}$ and $SO{_4}^{2-}$ were the most abundant cation and anion, respectively, in the fog water samples. A mean pH of 5.08 in the fog water, which is higher than those in rural areas in Japan, was observed. The [$NH_4{^+}$]/[$SO{_4}^{2-}$] equivalent ratio in fog water was larger than 1.0 throughout the study period, indicating that $NH_3$ gas was the primary neutralizing agent for fog water acidity. The mean rate and total amount of fog water deposition were estimated as 0.15 mm $h^{-1}$ and 164 mm, respectively. The amounts of nitrogen and sulfate deposition via fog water deposition were corresponded to those reported values of the annual deposition amounts via rainfall.