• Korean Journal of Environment and Ecology
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• v.26 no.5
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• pp.707-718
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• 2012

This study was conducted to monitor 4 years of changes in the vegetation structure starting from 2007 when restoration began and propose vegetation management ideas for the riparian ecological restoration areas in the purchased land around Nakdonggang(River). The study was conducted in each of 15 locations ($208,342m^2$) in the riparian ecological restoration areas in November 2007, September 2008, October 2009 and September 2010. The analysis results of the changes in planting species and population showed that, in the case of trees, Acer pseudo-sieboldianum, Quercus acutissima, Acer ginnala, Quercus aliena, Quercus variabilis indicated relatively little changes in their numbers and Quercus dentata, Cornus walteri, Morus alba, Styrax obassia, Sorbus alnifolia var. macrophylla indicated a 100% withering rate. Most shrubs withered due to the oppressive pressure of herbs and climbing plants. The planting density decreased over 4 years on average 28 plants/$100m^2$ to 20 plants/$100m^2$ to 16 plants/$100m^2$. Shortly after the restoration, The the amount of growth was reduced by restoration stress. however as time goes on after the restoration tended to stabilize. The changes in the basal area showed a decrease from $507.1cm^2/100m^2$ in 2007 right after restoration to $301.8cm^2/100m^2$ in 2008 and afterwards showed an increasing trend by going to $324.9cm^2/100m^2$ in 2009 and $372.7cm^2/100m^2$ in 2010. To improve the planting structure of the riparian ecological restoration area, the selection of tree species that have been considered for soil moisture and the differentiation of suitable planting structures that have been considered for local conditions were needed.

• Journal of the Korean Wood Science and Technology
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• v.2 no.3
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• pp.3-16
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• 1974

One of the disadvantages of. wood and wood products is their hydroscopicity or dimensional instability. This is responsible for the loss of green volume of lumber as seasoning degrade. Dimensional stabilization is needed to substantially reduce seasoning defects and degrades and for increasing the serviceability of wood products. Recently, considerable world-wide attention has been drawn to the so-called Wood-Plastic Composites by irradiation-and heat-catalyst-polymerization methods and many research and developmental works have been reported. Wood-Plastic Composites are the new products having the superior mechanical and physical properties and the combinated characteristics of wood and plastic. The purpose of this experiment was to obtain the basic data for the improvement of wooden materials by manufacturing WPC. The species examined were Mulpurae-Namoo (Fraxinus, rhynchophylla), Sea-Namoo (Carpinus laxiflora), Cheungcheung-Namoo (Cornus controversa), Gorosae-Namoo (Acermono), Karae-Namoo(Juglans mandshurica) and Sanbud-Namoo (Prunus sargentii), used as blocks of type A ($3{\times}3{\times}40cm$) and type B ($5{\times}5{\times}60cm$), and were conditioned to about 10~11% moisture content before impregnation in materials humidity control room. Methyl methacrylate (MMA) as monomer and benzoyl peroxide (BPO) as initiator are used. The monomer containing BPO was impregnated into wood pieces in the vacuum system. After impregnation, the treated samples were polymerized with heat-catalyst methods. The immersed weights of monomer in woods are directly proportionated to the impregnation times. Monomer impregnation properties of Cheungcheung-Namoo, Mulpurae-Namoo and Seo-Namoo are relatively good, but in Karae-Namoo, it is very difficult to impregnate the monomer MMA. Fig. 3 shows the linear relation between polymer retentions in wood and polymerization times; that is, the polymer loadings are increasing with polymerization times. Furthermore species, moisture content, specific gravity and anatomical or conductible structure of wood, bulking solvents and monomers etc have effects on both of impregnation of monomer and polymer retention. Physical properties of treated materials are shown in table 3. Increasing rates of specific gravity are ranged 3 to 24% and volume swelling 3 to 10%. ASE is 20 to 46%, AE 14 to 50% and RWA 18 to 40%. Especially, the ASE in relation to absorption of liquid water increases approximately with increase of polymer content, although the bulking effect of the polymerization of monomer may also be influential. WPCs from Mulpurae-Namoo and Cheungcheung-Namoo have high dimensional stability, while its of Karae-Namoo and Seo-Namoo are-very low. Table 4 shows the mechanical properties of WPCs from 6 species. With its specific gravity and polymer loading increase, all mechanical properties are on the increase. Increasing rate of bending strength is 10 to 40%, compression strength 25 to 70%, ;impact bending absorbed energy 4 to 74% and tensile strength 18 to 56%. Mulpurae-Namoo and Cheungcheung-Namoo with high polymer content have considerable high increasing rate of strengths. But incase of Karae-Namoo with inferior monomer impregnation it is very low. Polymer retention in cell wall is 0.32 to 0.70%. Most of the polymer is accumulated in cell lumen. Effective. of polymer retention is 58.59% for Mulpurae-Namoo, 26.27% for Seo-Namoo, 47.98% for Cheungcheung-Namoo, 25.64% for Korosae-Namoo, 9.96% for Karae-Namoo and 25.84% for Sanbud-Namoo.

• Journal of Forest and Environmental Science
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• v.17 no.1
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• pp.1-17
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• 2001

Forming a part of "Cooperative Practical Study for the Modernization of the Management of National Forest", this study was conducted to provide overall ecological information for the natural regeneration of major tree species on the basis of community structural attributes in the deciduous forest ecosystem. Followings are summarized characteristics of the natural regeneration for the selected tree species. Betula costata : Although large number of seeds are dispersed by wind, they require mineral soils to germinate. Thick litter layer could be an obstacle to germinate. After germination, the seedling requires large amount of light for successful establishment. Acer mono : Characterized by high shade tolerance and weak drought resistance, the seedling should be overcasted with more than 50% of canopy coverage. High stand density should be maintained to produce good quality of timber. The potential of coppice may be high. Ulmus laciniata : Since this species needs high rate of troll moisture and light, around 60% of canopy coverage should be maintained to retain moisture and incoming light. The competition with other vegetation should be removed for the favor of successful seedling establishment. Fraxinus mandshurica : This species requires moist mineral soils to germinate. After germination, the seedling needs large amount of light and moisture for successful establishment. Site preparation should be applied to reduce competition with weedy vegetation. Fraxinus rhynchophylla : Interval of large seed crops may be highly varied. Thick litter layer could be an obstacle to germinate. Site preparation should be applied to reduce competition with weedy vegetation so as to achieve successful seedling establishment. Quercus mongolica : Including the difficulty of seed supply by the consumption, thick litter layer and mountain bamboo cover could be the obstacle to germinate. More than 50% of relative light intensity is necessary to achieve successful seedling establishment. Kalopanax pictus : Thick litter layer could be an obstacle to germinate. The seedling needs large amount of light and moisture for successful establishment. Abies holophylla : In spite of high shade tolerance, the growth rate in sapling stage may be extremely slow. Cornus controversa : Seeds (drups) are consumed and dispersed by animals, tending to be not sufficient in seed supply. This species requires large amount of light for successful germination and seedling establishment. Tilia amurensis : The difficulty of seed supply might be expected with low seed purity and double dormancy. Since thick litter layer could be an obstacle to germinate, the species requires moist mineral soils for successful germination. The potential of coppice may be extremely high.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.289-300
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• 2013

Forest vegetation of Hyangjeokbong (1,614 m) in Deogyusan National Park is classified into mountain forest vegetation and flatland forest vegetation. Mountain forest vegetation is subdivided into deciduous broad-leaved forest, valley forest, coniferous forest, subalpine coniferous forest, shrub forest, grassland forest, afforestation and etc., while riparian forest was found under the category of flatland forest vegetation. Including 122 communities of mountain forest vegetation and 2 communities of riparian forest, the total of 124 communities were researched; the distributed colonies classified by physiognomy classification are 42 communities deciduous broad-leaved forest, 37 communities of valley forest, 8 communities of coniferous forests, 6 communities of subalpine coniferous forest, 3 communities of shrub forest, 1 communities of grassland forest, 21 afforestation and 4 other communities. As for the distribution rate for surveyed main communities, Quercus mongolica, Quercus serrata, Quercus variabilis communities account for 47.02 percent of deciduous broad-leaved forest, Fraxinus mandshurica community takes up 57.48 percent of mountain valley forest, Pinus densiflora community holds 77.53 percent of mountain coniferous forest holds, and Taxus cuspidate-Abies koreana community takes up about 50 percent of subalpine coniferous forest. Mountain shrub forest and mountain grassland forest vegetation are concentrated mainly on the top of Hyangjeokbong and the ridge connecting the top and Jungbong. Meanwhile, riparian forest vegetation comprises 0.024% of the whole vegetation area in a study area. In conclusion, minority species consisting of Quercus mongolica, Quercus serrata, Quercus variabilis, Fraxinus mandshurica, Cornus controversa, Pinus densiflora, Abies koreana and Taxus cuspidata are distributed as dominant species of the uppermost part in a forest vegetation region in Deogyusan National Park. In addition, because of vegetation succession and climate factors, numerous colonies formed by the two species are expected to be replaced by Quercus mongolica, Carpinus laxiflora and Fraxinus mandshurica which are climax species in the area. However, in respect of subalpine coniferous forest, the distribution rate of deciduous broad-leaved forest seems to increase gradually due to global warming and artificial disturbance.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.5
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• pp.13-21
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• 2014

This study generated regression models to quantify storage and annual uptake of carbon from five native landscape tree species through a direct harvesting method, and established essential information to estimate carbon reduction effects from urban greenspaces. Tree species for the study included the Chionanthus retusus, Prunus armeniaca, Abies holophylla, Cornus officinalis, and Taxus cuspidata, which are usually planted in cities of middle Korea, but for which no information on carbon reduction is available. Ten tree individuals for each species were sampled reflecting various stem diameter sizes at a given interval. The study measured biomass for each part including the roots of sample trees to compute total carbon storage per tree. The annual carbon uptake per tree was quantified by analyzing the radial growth rates of stem samples at breast height or ground level. Regression models were developed using diameter at breast height (dbh) or ground level (dg) as an independent variable to easily estimate storage and annual uptake of carbon per tree for each species. All the regression models showed high fitness with $r^2$ values of 0.92~0.99. Storage and annual uptake of carbon from a tree with dbh of 10 cm were greatest with C. retusus (20.0 kg and 5.9 kg/yr, respectively), followed by P. armeniaca (17.5 kg and 4.5 kg/yr) and A. holophylla (13.2kg and 1.8 kg/yr) in order. A C. officinalis tree and T. cuspidata tree with dg of 10 cm stored 9.3 and 6.3 kg of carbon and annually sequestered 3.2 and 0.6 kg, respectively. The above-mentioned carbon storage equaled the amount of carbon emitted from gasoline consumption of about 23~35 L for C. retusus, P. armeniaca, and A. holophylla, and 11~16 L for C. officinalis and T. cuspidata. A tree with the diameter size of 10 cm annually offset carbon emissions from gasoline use of about 6~10 L for C. retusus, P. armeniaca, and C. officinalis, and 1~3 L for A. holophylla and T. cuspidata. The study breaks new ground to easily quantify biomass and carbon reduction for the tree species by overcoming difficulties in direct cutting and root digging of urban landscape trees.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.150-157
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• 2006

The aim of the present study was to investigate the effect of combined extract of safflower seed with herbs on the improvement of blood glucose, lipid peroxides, lipids in the plasma and liver of strpetozotocin-induced diabetic rats. Rats in the experimental group were orally administered with combined extract of safflower seed (100 mg, 200 mg/kg B.W.) with herbs (Ophiopogon japonicus Ker-Gaqler, Glycyrrhiza uralensis Fisch, Mori Folium, Poria cocos, Rehmannia glutinosa, Eriobtrya japonica, Aralia continentalis Kitagawa, Zizyphus jujuba var, Cornus officinalis, Paeonia suffruticosa, Trichosanthes kirilowii Maxim and Schizandra chinensis Baill) for 4 weeks. Body weight gain and food efficiency ratio were significantly lower in diabetic groups than those of control group. These were no protective effect of the supplementation of combined extract of safflower seed with herbs. Concentration of blood glucose was significantly higher in the diabetic groups than those in the control group. Blood glucose concentration was remarkably lower supplementation of combined extract of safflower seed (200 mg/kg B.W.) with herbs. There was no significant difference of plasma lipid peroxides among experimental groups, while liver lipid peroxides of diabetic group was significantly higher in control group. But supplementation of combined extract of safflower seed with herbs was induced markedly lower in liver lipid peroxides in diabetic rats. Diabetic groups had markedly higher levels in triglycerides, LDL-cholesterol and atherogenic index, while had lower HDL-cholesterol level. Triglyceride levels of plasma and liver were significantly lower with combined extract of safflower seed with herbs. But total cholesterol, phospholipid and free fatty acid were no differing significantly among experimental groups.

• Korean Journal of Ecology and Environment
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• v.49 no.1
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• pp.31-41
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• 2016

Deutzia paniculata is an endemic species to the Korean Peninsula. Despite of importance for conservation, the population structure and habitat characteristics of D. paniculata have not been determined yet. We analyzed the ecological characteristics of the species based on the literature review and field survey. Field survey was conducted on May to October 2014 during which 11 quadrats of size $15{\times}15m$ were studied in six regions. Each of the quadrats were further divided into $5{\times}5m$ small quadrats and population characteristics were recorded. The population and habitat characteristics were analyzed, including species abundance (density and coverage), demographic attributes (flowering rates and fruiting plants), vegetation (structure, species composition), light availability (transmitted light and canopy openness) and soil characteristics (temperature and humidity). We found that D. paniculata mainly distributed in Gyeongsangdo (including Taebaek in Gangwondo) along a broad elevational range of 290~959 m (mean: 493 m) above sea level. In preferred habitat the species grows within the slope range of $7^{\circ}$ and $35^{\circ}$ with the average of $16^{\circ}$. D. paniculata was generally distributed on talus deposits and low adjacent slopes. The average number of individual plants per small quadrat was 12.5 with the mean density $0.5stems\;m^{-2}$. The vegetative reproduction was frequent in D. paniculata and mean flowering rate was as low as 15%. Altogether 138 taxa were found in whole observation area with the dominant tree species mainly spring ephemerals, such as Cornus controversa (importance value: 25.5%) and Fraxinus rhynchophylla (importance value: 15.8%). Although, C. controversa usually grows on steep slopes and F. rhynchophylla mostly distributed at high-altitudes, however, both species distributed in disturbed environments and among talus deposits. Thus based on our results, we concluded that D. paniculata is a disturbance-prone species, primarily existing in habitats subjected to natural disturbances, such as floods. The species occurs less at anthropogenically disturbed sites, thus there is no apparent threat to the populations and habitat of D. paniculata.

• Korean Journal of Ecology and Environment
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• v.48 no.1
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• pp.51-60
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• 2015

Forest vegetation of Youngbong (1,094 m) in Woraksan National Park is classified into mountain forest vegetation. Mountain forest vegetation is subdivided into deciduous broad-leaved forest, mountain valley forest, coniferous forest, riparian forest, afforestation and other vegetation. Including 84 communities of mountain forest vegetation and 7 communities of other vegetation, the total of 91 communities were researched; mountain forest vegetation classified by physiognomy classification are 39 communities deciduous broad-leaved forest, 26 communities of mountain valley forest, 6 communities of coniferous forests, 2 communities of riparian forests, 11 afforestation and 7 other vegetation. As for the distribution rate for surveyed main communities, Quercus mongolica, Quercus variabilis communities account for 40.879 percent of deciduous broad leaved forest, Fraxinus mandshurica - Cornus controversa community takes up 25.627 percent of mountain valley forest, Pinus densiflora community holds 75.618 percent of mountain coniferous forest holds. In conclusion, minority species consisting of Quercus mongolica, Pinus densiflora, Quercus variabilis, Fraxinus mandshurica, and Quercus serrata are distributed as dominant species of the uppermost part in a forest vegetation region in Woraksan National Park. In addition, because of vegetation succession and climate factors, numerous colonies formed by the two species are expected to be replaced by Quercus mongolica, Quercus variabilis and Fraxinus mandshurica which are climax species in the area.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.580-589
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• 2015

The artificially grown forests of larch, planted in accordance with the nationwide afforestation policy in the 1970s, are located inside national parks. This study intended to induce a forestation system by which the forests develop into an ecologically healthy and broadleaved ecosystem with broad species diversity. For this, the aspects of natural regeneration of broadleaves from 2010 to 2013 after thinning by density (30%, 50%, and 70%) in 2009 were surveyed using the larch forest in the Woljeong Temple region inside Odaesan National Park. There were no trees that were larger than 2 cm in in diameter at breast height among the trees recently introduced between 2012 and 2013. A significant number of herbs have been introduced to the subsurface alongside young arboreal trees species such as Bumalda bladdernut, Acer triflorum, Cornus controversa etc and shrubs. However, many woody species did not survive the competition with herbs and repeated withering and regeneration. The number of woody species generated within the 30% cutting area was 440 species in 2013 and this figure has been increasing twofold each year. The number of woody plants within the 50% cutting area also showed an upward tendency and most plants did not survive in the competition with herbs and Sasa borealis and withered in only 1 ~ 2 years after generation. Unlike other thinning areas, the 70% cutting area showed 608 broadleaved trees, reflecting a decrease from 748 trees in 2012. This appeared to be attributed to the luxuriance of S. borealis and the sharp increase of fatsia following the inflow of total sunlight to the forest floor. Herbs were hardly generated due to the influence of S. borealis. Regarding the density for thinning at 50% or upper height, the forest treatment division shall maintain a proper density in the course of inducing artificial forestation of larch into natural broadleaved forests considering the luxuriance of sasa borealis and herbs due to the inflow of total sunlight to the forest floor.

• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.284-294
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• 2011

This study was conducted to investigate the flora of habitats distributed with Allium victorialis var. platyphyllum populations in the South Korea. The vascular plants were surveyed 4 times from March 2009 to June 2010. The flora of studied area was listed as 214 taxa; 64 families, 142 genus, 181 species, 2 subspecies, 30 varieties, 1 forma. According to the specific plant species by classes, class I has 17 taxa; 15 families, 16 genus, 15 species, 2 varieties. Class II has 16 taxa; 13 families, 16 genus, 15 species, 2 varieties. Class III has 20 taxa; 16 families, 19 genus, 18 species, 2 varieties. Class III has 20 taxa; 16 families, 19 genus, 18 species, 2 varieties. Class IV has 23 taxa; 20 families, 23 genus, 19 species, 4 varieties. Class V has 2 taxa; 2 families, 2 genus, 2 species. Rare plant was 12 taxa; 9 families, 11 genus, 10 species, 2 varieties. Endemic plant was 21 taxa; 17 families, 19 genus, 18 species, 3 varieties. Endangered plant was not present in study area. It was considered that the ecosystem was probably stabilized for nothing of naturalized species and ecosystem disturbance species there. The characteristics of growth environments in the habitats with Allium victorialis var. platyphyllum were considered to be related to valley species and subalpine species such as Actinidia polygama, Cornus controversa, Rhododendron brachycarpum and Sorbus commixta.