• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.5
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• pp.105-112
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• 2017

In order to analyze the effect of street trees on human thermal sensation(thermal comfort) in summer, microclimatic data were measured and analyzed at sunny and shaded locations of two deciduous broadleaf and three broadleaf evergreen species of street trees. As a result, the mean differences by species in air temperature, relative humidity and wind speed were small: $0.2{\sim}1.5^{\circ}C$, 0.9~5.3% and $0.1{\sim}0.5 ms^{-1}$, respectively, but the mean difference in the mean radiant temperature was great, $27.1^{\circ}C$. In the results of physiological equivalent temperature(PET) and universal thermal climate index(UTCI), which are human thermal sensation(thermal comfort) indexes, the shaded locations by the trees showed mean reduction rates of 21.2~31.3% in the PET compared with the sunny location, which are equivalent to 1.5~2.5 levels of thermal perception. Also, 12.7~20.0% in the UTCI was reduced by the trees' shadows, which is equivalent to 1~1.5 levels of heat stress. In addition, although the broadleaf evergreen trees had 5% greater mean reduction in PET than that of the deciduous broadleaf trees, the Zelkova serrata that belonged to the deciduous broadleaf trees showed the equivalent thermal reduction effect as the broadleaf evergreen trees because of the high density of branches and leaves. Therefore, the mean radiant temperature and the density of the crown(branches and leaves) were the main influences in thermal modification by these street trees in summer.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.229-236
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• 2018

Pesticides are widely sprayed by the growers in street trees and planting areas which include urban forests, community forests and city parks to control pests. Spraying pesticides not only affect the people who sprayed but also affect the unspecified citizens who's are exposed to pesticides sprayed trees by contact or inhalation. A few studies have been conducted to measure the amount of pesticides in forest area but no studies have been conducted to measure the pesticide amount in tree in public living space. So, in our study, we investigated the amount of pesticides in cotton gloves, in leaf residue, and respiratory exposure for a certain period of time after applying Fenitrothion EC to Korean boxweed tree (Buxus Koreana) to know the safety time of pesticides after spraying. We found that, up to 4d, there was no significant difference of the amount of Fenitrothion on leaves. But the amount of pesticides on gloves was significantly higher on 1h ($510.1{\mu}g$) and 24h ($405.4{\mu}g$) than 48h ($45.0{\mu}g$) after spraying. The amount of pesticides on inhalation was also significantly higher in 1 h ($0.2{\mu}g$) and 24 h ($0.1{\mu}g$) than 48 h after spraying. After 48h, we did not find pesticides amount in inhalation. Thus, we was considered necessary to pay attention to 48h after spraying of pesticide Fenitrothion.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.439-445
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• 2009

Species richness (number of species) of the butterfly community in the Gwangneung forest, Korea, was estimated using data of the long-term butterfly monitoring, which had been carried out 291 times in the Korea National Arboretum or forest area of Gwangneung from 1998 to 2008. Abundance of each butterfly species was monitored using the line-transact method. In the present study, 13,333 butterflies belonging to 112 species were observed. Species accumulation curve and species richness was obtained using a software, EstimateS. The species accumulation curve shows an increase tendency even at 291 survey times, implying the possibility of the presence of a few unfound species. However, values of species richness estimated by the seven estimators were stabilized around 240-250 survey times. Species richness estimated by the estimators ranged from 120 species to 141 species with 128 species in average. However, the figure estimated by the previous studies since 1958 was 148 species. We estimated the reasonable scale of species richness on the base of recent analysis on the change of butterfly species. Species richness of the Korea National Arboretum was higher than that of natural forest and of plantation. However, species richness of butterfly was not different between natural forest and plantation. It is likely that increase of grasslands and habitat diversity in arboretum led to the increase of species richness of butterfly community.

• Korean Journal of Plant Resources
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• v.37 no.1
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• pp.22-34
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• 2024

Recently, in several regions of Korea, we discovered the occurrence of Sagina micropetala Rauschert and S. procumbens L. All the plants of the genus Sagina growing in Korea are 5-merous and belong to the sect. Spergella. However, the two taxa we discovered belong to the sect. Saginella and are 4-merous. In addition, morphological characteristics such as sepals during the fruiting season and seeds were significantly different from those of species of the genus Sagina that occur in Korea. To clearly identify these species, we compared and observed their primary morphological characteristics using illustrated books and literature. Morphologically, S. micropetala exhibits the following traits: pubescence along the leaf margin, horizontally spreading sepals with red margins, and convex protrusions on the seed surface. In contrast, S. procumbens can be distinguished by its pedicels, which are curved during the flowering season and erect during the fruiting season. This plant also has broadly ovate sepals with white or yellowish-green margins, and flat seed surface protrusions. In terms of molecular analyses, 19 samples of Sagina were divided into two clades (S. micropetala and S. procumbens), confirming the taxonomic identity of the Sagina spp.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.100-117
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• 2010

This study analyzed vegetation structure of natural monuments Koelreuteria paniculata community in search of a conservation and management plan. Plant sociological analysis of Koelreuteria paniculata community indicates that it can be classified into Achyranthes japonica subcommunity and Rhodotypos scandens subcommunity and Trachelospermum asiaticum var. intermedium subcommunity. While Koelreuteria paniculata community of Ahnmyeondo is composed of sub tree layer and herb layer, those of Pohang and Wando are composed of tree layer, Sub tree layer, shrub layer, herb layer. The results of tree vitality analysis showed that those in Ahnmyeondo appeared to be relatively low when compared to those in Pohang and Wando-gun. This can be understood in two different aspects: disease and insects vulnerability due to a relatively simple structure and lack of competitive species, and decreased vitality / natural branch losses due to crown competition arising from high density. The result of soil characteristics analysis showed that soil texture, soil pH, organic matter, $p_2O_5$, exchange positive ion were sufficient for tree growth while total nitrogen was not, so that discretion would be needed for fertilizer application. As there were damages of disease and inscet, but only for 10~15% of the entire area; it still requires consistent preconsideration. The study suggests the management methods for preservation of Koelreuteria paniculata community. First, securing designated areas is necessary in order to minimize environment deterioration due to surrounding development. Especially, for sections with decreased areas, expansion of designated areas through land purchase should also be considered. Second, artificial interference may affect the livestock. Therefore, monitoring of artificial interference is necessary, based on which protection projects must be conducted. Third, from analysis of young plants which influence the maintenance mechanisms of Koelreuteria paniculata community, a decrease compared to the prior year was observed; investigation is needed. Therefore, an active management policy through status examination of livestock such as germination and young plants is necessary.

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.229-233
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• 1981

This study was to investigate ornamental trees injuries at the Tobong ornamental tree farm, which is located in Uichongpu City, Kyonggido. The injury was caused by $SO_2$ gas from the smoke of the vicinal factories. The results obtained are as follows: 1 The total concentration of sulfur in leaves was increased with incerased degree of injury The most severe injuries were found at the distance between 70-120m from the western boundary of the Tobong ornamental 4ree farm with a highest concentration of total sulfur at $0.5-0.6\%$. This means the injuries caused by the acute injury and the temperature changes. 2. Significant differences were found between normal and injured portion of the same trees in Juniperus chinensis. 3. Anatomical study of the leaf tissues, showed the plasmolysis occured both in spongy and epidermal cells, leading to shrinkage and destruction. An intercellular space and stomatal periphery became wider.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.1-8
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• 2001

The 90% methanol extracts of eight magnoliaceae plants were collected and tested the cytotoxicity against SK-OV-3 and SiHa cells. Also six pure compounds such as magnonol, honokiol, dihydroxybiphenyl ether, linodenine, anonaine, asimilobine which were previously isolated from Magnolia obovata Thunb. were evaluated the cytotoxicities and their mechanism study using the Lactate dehydrogenase assay(LDH) and FACScan analysis system. Of the tested six compounds, magnonol, honokiol, dihydroxybiphenyl ether showed high cytotoxicities against human cancer cell lines, SK-OV-3 and SiHa cells. In addition, one of the plausible mechanisms of their antitumor activities suggested that they could induce the early stage of apoptosis. For the quantitative analysis, the methanol extractives were fractionated with chloroform, ethylacetate, $H_2O$ and then the ethylacetate fraction was chromatographed on silica gel using n-Hexane ; Acetone(4:1, v/v) as eluent. This fraction was subjected for the quantitative analysis in the HPLC system. The result suggested that the methanol extractives of Magnolia obovata Thunb. contained with magnonol, honokiol, dihydroxybiphenyl ether, 0.9%, 0.3% and 0.24%, respectively.

• The Korean Journal of Quaternary Research
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• v.15 no.1
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• pp.53-61
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• 2001

To examine the effects of El Nino-Southern Oscillation (ENSO) on the tree growths of central Korea, tree rings of Korean pine(Pinus koraiensis) , Japanese red pine (Pinus densiflora) and yew (Taxus cuspidata) were analyzed. Korean pine and red pine samples were collected from 4 and 7sites in Sorak Mountain ranges, respectively ; yew from one site in Sobaek Mountain. Correlations between ring-width and monthly temperature data showed generally positive relationships for the Korean pine and yew chronologies, but negative ones for the red pine chronologies. In the analysis of correlation between ring-width and monthly S0 index data, only one Korean pine chronology at the lower Hangaerung valley site, and one red pine chronology at Baekdamjang shelter site showed significant relationships ; negative with April SOI for the former and positive with previous August-September SOI for the latter. The other chronologies at higher elevation sites did not indicate any significant correlations with SOI.

• Korean Journal of Environment and Ecology
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• v.35 no.5
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• pp.548-557
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• 2021

Cypripedium japonicum Thunb. is an endemic plant in East Asia, distributed only in Korea, China, and Japan. At the global level, the IUCN Red List evaluates it as "Endangered Species (EN)," and at the national level in Korea, it is evaluated as "Critically Endangered Species (CR)." In this study, we investigated the characteristics of the age structure and the sustainability of the population based on the data obtained by demographic monitoring conducted for seven years in the natural habitat. C. japonicum habitats were observed in 7 regions of Korea (Pochoen, Gapyeong, Hwacheon, Chuncheon, Yeongdong, Muju, Gwangyang), and 4,356 individuals in 15 subpopulations were identified. The population size and structure differed from region to region, and artificial management had a very important effect on the size and structural change of the population. Population viability analysis (PVA) based on changes in the number of individuals of C. japonicum showed a very diverse tendency by region. And the probability of population extinction in the next 100 years was 0.00% for Pocheon, 10.90% for Gwangyang, 24.05% for Chuncheon, and 79.50% for Hwacheon. Since the above monitored study sites were located within the conservation shelters, which restricted access by humans, unauthorized collection of C. japonicum, the biggest threat to the species, was not reflected in the individual viability. So, the risk of extinction in Korea is expected to be significantly higher than that estimated in this study. Therefore, it is necessary to reflect population information in several regions that may represent various threats to determine the extinction risk of the C. japonicum population objectively. In the future, we should expand the demographic monitoring of the C. japonicum population known in Korea.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.1
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• pp.27-35
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• 1988

Size characteristics of three widely used landscape trees were analized to establish a methodology of size prediction as time Passes. Tree height, tree width, stem diameter(breast or surface), canopy length and tree age were measured directly and indirectly(by using photograph), and the data were analized by using regression analysis through PC-SAS. The results are summarized as follows : 1. Zelkova serrata MAKINO showed relatively slow growth rate and the tree form was changed as aged. Size predictions were available by using the regression equations listed below : Surface diameter = 0.8293 x AGE Tree height = 0.4109(0.8293 x AGE) - 0.0039(0.7273 x AGE)$^2$Tree width = 0.3240(0.8293 x AGE) - 0.0024(0.1293 x AGE)$^2$Canopy length = 0.1337(0.8293 x AGE) - 0.0020(0.7293 x AGE)$^2$2. Pinus strobus L. showed relatively fast growth rate and the tree form did not change much as aged. Size predictions were available by using the regression equations listed below. Breast diameter = 0.756 x AGE Tree height = 0.7695(0.756 x AGE) - 0.0164(0.75\ulcorner x AGE)$^2$Tree width = 0.4331(0.756 x AGE) - 0.0079(0.75\ulcorner x AGE)$^2$Canopy length = 0.1365(0.756 x AGE) - 0.0032(0.75f x AGE)$^2$ 3. In case of Magnolia denudata DESROUX, tree form was determined relatively earlier than the other two species. Si2e predictions were available by using the regression equations listed below : Surface diameter = 0.88 x AGE Tree height = 0.5412(0.88 x AGE) - 0.0110(0.88 x AGE)$^2$ Tree width = 0.3752(0.88 x AGE) - 7.0061(0.88 x AGE)$^2$Canopy length = 0.1110(0.88 x AGE) - 0.0022(0.88 x AGE)$^2$ This study aimed to find a way to predict size change of landscaping plants. This methodology will be applied to a wide range of landscape plants to provide practical data to landscape designers.