• Journal of Korea Foresty Energy
• /
• v.23 no.2
• /
• pp.1-8
• /
• 2004

This study looked into the change of tree growth of seven forest growth monitoring plots which were set up at the Undulyeong Hongchungun Kangwondo, and was accomplished to offer the basic data for the forest administration calculating carbon storage and removal in the Undulyeong area. Annual height and DBH growth were slowly progressed in the Pinus koraiensis and Larix kaempferi stand which was young stand, but the growth rate of the other stands was lower than those young stand. The diameter class of the mixed forest and Qurcus mongilica stand was predicted to be similar to the now and Pinus koraiensis and Larix kaempferi stand was predicted to move now diameter class to the high diameter class because thickening growth speed of the those stands were rapid. Now the end of 2003, total carbon storage of the Undulyeong model forest increased 149,000TC$(2.7\%)$ compared with the previous year. Seeing by forest types, occupied broad-leaved forest$(50\%)$, mixed forest$(34\%)$ and coniferous forest. During in 2003, total carbon which was removed and stored according to growth of the forest was 156,813TC and net carbon removal(148,664TC) increased into 2,613TC$(1.8\%)$ compared with the previous year. Seeing by forest types, occupied coniferous forest$(3.3\%)$, mixed forest$(3.1\%)$, broad-leaved forest$(2.8\%)$. Resultingly, the Undulyeong model forest is acting to net removal resource when see as green-gas side and net carbon removal are showing the tendency to increase recently little by little.

• Journal of Korean Society of Forest Science
• /
• v.96 no.2
• /
• pp.160-169
• /
• 2007

The data used to develop distance-independent individual models for natural mixed forests were collected from 712 remeasured permanent sample plots (25,526 trees) of 10-year periodic from 1990 to 2000 in Baihe Forest Bureau of Changbai Mountains, northeast China. Based on analyzing relationship between diameter increment of individual trees with tree size, competitive status, and site condition, the diameter growth models for individual trees of 15 species growing in mixed-species uneven-aged forest stands, that have simple form, good predicting precision, and easily applicable, were developed using stepwise regression method. The main variables influencing on diameter increment of individual trees were tree size and competition, however, the site conditions were not significantly related with diameter increment. The tree size variables (lnDBH and $DBH^2$) were the most significant and important predictors of diameter growth existing in all 15 growth models. The diameter increment was directly proportional to tree diameter for each species. For the competitive factors in growth model, the relative diameter (RD), canopy closure (P), and the ratio of diameter of subject tree with maximum diameter (DDM) were contributed to the diameter increment at a certain extent. Other measures of stand density, such as basal area of stand (G) and stand density index (SDI), were not significantly influenced on diameter increment. Site factors, such as site index, slope and aspect were not important to diameter increment and excluded in the final models. The total variance explained by the final models of squared diameter increment ($R^2$) for all 15 species ranged from 35% to 72% and these results compared quit closely with those of Wykoff (1990) for mixed conifer stands. Using independent data set, validation measures were evaluated for predicting models of diameter increment developed in this study. The result indicated that the estimated precision was all greater than 94% and the models were suitable to describe diameter increment.

• Journal of Korean Society of Forest Science
• /
• v.99 no.5
• /
• pp.673-681
• /
• 2010

This study examined the biomass data estimated from different allometric models and calculated the mean aboveground biomass, mean belowground biomass and root/shoot ratio values according to the forest types and age classes. These mean values and the forest inventories in 2009 were used to estimate the aboveground and total biomass carbon storage in different forest types (coniferous, deciduous and mixed forests). The aboveground and total biomass carbon storage for all forest types in Korea were 350.201 Tg C and 436.724 Tg C. Over the past 36 years, plantations by reforestation programs have accounted for more than 70% of the observed carbon storage. The carbon storage in Korean forest biomass was 436.724 Tg C, of which 175.154 Tg C for coniferous forests, 126.772 Tg C for deciduous forests and 134.518 Tg C for mixed forests, comprising approximately 1/20 of the total carbon storage of the East Asian countries. The total carbon storage for the whole forest sector in Korea was 1213.122 Tg C, of which 436.724 Tg C is stored in forest biomass if using the ratio of carbon storage in different pools examined from the United States. Such large carbon storage in Korean forests is due mainly to active plantations growth and management practices.

• Journal of Ginseng Research
• /
• v.4 no.1
• /
• pp.16-30
• /
• 1980

In order to increase the production of ginseng, a cultural experiment was carried out under different types of natural forest condition. Seedlings were transplanted with three spacing (70,90 and plants per 1.62m2) under the broad leaved, needle and mixed forest. The obtained results are as follows. 1 Growth of aerial part of ginseng plant. 1) Vegetative growth under forest condition of very poor as compared with ordinary cultivation, but there was no significant in number of leaf and teasel. 2) Stem diameter and stem length under the different forest types were a little difference. However petiole length and number of leafet showed an increasing trend in broad leaved forest as compared with other forest types. 3) The withering date of aerial part of ginseng plant in the needle forest was later than of others. 2. Fresh weight of ginseng root per plant was decreasing in the order of broad leaved forest, needle and mixed forest, needle and sized forest respectively. However the root weight was much smaller than that of ordinary cultivated one. 3. No big difference was observed in the growth of both aerial and root among the planting density 4. Nitrogen content in ginseng root under forest was lower, but calcium content In root was higher than that of ordinary one. 5. Fat and fiber content of ginseng root under forest showed higher than that of ordinary one. 6. The saponin content of ginseng root grown under forest condition was higher than that of ordinary ginseng root. According to high performance liquid chromatogram of saponin, only difference from ordinary cultivated ginseng root was that ginsenoside Re showed higher peak than ginsenoside Rg1.

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.4
• /
• pp.346-357
• /
• 2013

In this study, it was conducted to produce wood pellets using domestic forest thinning residues and examine their quality according to Korean pellet quality standard. Raw materials were composed of larch and mixed broad leaves species. Based on the small-end diameter (6 cm), they were classified into four different types of raw materials such as LM (larch with middle diameter), LS (larch with small diameter), MM (mixed broadleaf with middle diameter), and MS (mixed broadleaf with small diameter). After crushing and drying process, wood pellets were produced by a ring-die type pelletizer using each raw material. Wood pellets made from four different types of raw materials were tested for their quality such as calorific value, moisture content, ash content, inorganic matters and so on. As results of quality analysis, the calorific values of all wood pellets were higher than 198 kcal/kg, and satisfied with the first grade of Korea wood pellet standard. The ash content was slightly increased after pelletizing. Mechanical durability of wood pellets was highly dependent on the types of raw materials. The quality differences among wood pellets were turned out due to different physical and chemical characteristics of raw materials even though the same pelletizing condition was applied.

• Journal of Korean Society of Forest Science
• /
• v.110 no.3
• /
• pp.431-439
• /
• 2021

The present study evaluated the antioxidant activity, skin wrinkle reduction, and whitening activity of Pinus koraiensiscone scale extracts made with three different solvents (ethanol, supercritical fluid, and a mixture of both). Total polyphenol content was 11.03 mg/g GAE in the supercritical fluid extractand 33.79 mg/g GAE in the 70% ethanol extract. Electron donating ability of 1,000 ㎍/mL extract was 13.60% in the supercritical fluid extract, 91.37% in 70% ethanol extract, and 71.62% in mixed solvent extract. SOD-like activities in 100 ㎍/mL extract using supercritical fluid, 70% ethanol, and mixed solvents were 16.49%, 21.84%, and 10.7%, respectively. The ABTS⁺ radical scavenging activities of 1,000 ㎍/mL extract were 38.19%, 80.23%, and 78.72%for supercritical fluid extract, 70% ethanol extract, and mixed solvent extract, respectively. Tyrosinase inhibitory activities in 1,000 ㎍/mL extract were 24.54%, 36.55%, and 15.23% for supercritical fluid extract, 70% ethanol extract, and mixed solvent extract, respectively. Elastase inhibitory activities in 1,000 ㎍/mL extract were 15.62%, 22.56%, and 26.64% for supercritical fluid extract, 70% ethanol extract, and mixed solvent extract, respectively. Skin astringent activity (81.23% with 5000 ㎍/mL extract) was only detected in the 70% ethanol extract. Supercritical fluid and mixed solvent extracts showed no such activity. Our analysis of Pinus koraiensiscone scale extracts show that the highest aggregate activity was found in the 70% ethanol extract, followed by mixed solvent and supercritical fluid extracts. Therefore, our results oppose the hypothesis stating supercritical extract has the highest total polyphenol content and antioxidant activity.

• Journal of Environmental Impact Assessment
• /
• v.20 no.4
• /
• pp.523-538
• /
• 2011

This study analyzes the changes in the surface area of each forest cover, based on temperature data analysis and satellite imagery as the basic methods for the impact assessment of climate change on regional units. Furthermore, future changes in the forest cover are predicted using the double exponential smoothing method. The results of the study have shown an overall increase in annual mean temperature in the studied region since 1990, and an especially increased rate in winter and autumn compared to other seasons. The multi-temporal analysis of the changes in the forest cover using satellite images showed a large decrease of coniferous forests, and a continual increase in deciduous forests and mixed forests. Such changes are attributed to the increase in annual mean temperature of the studied regions. The analysis of changes in the surface area of each forest cover using the statistical data displayed similar tendencies as that of the forest cover categorizing results from the satellite images. Accordingly, rapid changes in forest cover following the increase of temperature in the studied regions could be expected. The results of the study of the forest cover surface using the double exponential smoothing method predict a continual decrease in coniferous forests until 2050. On the contrary, deciduous forests and mixed forests are predicted to show continually increasing tendencies. Deciduous forests have been predicted to increase the most in the future. With these results, the data on forest cover can be usefully applied as the main index for climate change. Further qualitative results are expected to be deduced from these data in the future, compared to the analyses of the relationship between tree species of forest and climate factors.

• Journal of Forest and Environmental Science
• /
• v.32 no.3
• /
• pp.237-252
• /
• 2016

Improved knowledge of the environmental factors affecting the natural regeneration of tree species in limestone forest is urgently required for species conservation. We examined the environmental factors and tree species characteristics that are important for colonization in diverse forest stands growing on a limestone hill in northern Thailand. Our analysis estimated the relative influence of forest structure and environmental factors on the regeneration traits of tree species. We established sixty-four $100-m^2$ plots in four forest stands on the limestone hill. We determined the species composition of canopy trees, regenerating seedlings, and saplings in relation to the physical environment. The relationships between environmental variables and tree species abundance were assessed by canonical correspondence analysis (CCA), and we used generalized linear mixed models to examine data on seedling/sapling abundances. The CCA ordination indicated that the abundance of tree species within the mixed deciduous forest was closely related to soil depth. The abundances of tree species growing within the sink-hole and hill-slope stands were positively related to the extent of rocky outcropping; light and soil moisture positively influenced the abundance of tree species in the hill-cliff stand. Physical factors had a greater effect on tree regeneration than did factors related to forest structure. Tree species, such as Ficus macleilandii, Dracaena cochinchinensis, and Phyllanthus mirabilis within the hill-cliff or sink-hole stand, colonized well on large rocky outcroppings that were well illuminated and had soft soils. These species regenerated well under conditions prevailing on the limestone hill. The colonization of several species in other stands was negatively influenced by environmental conditions at these sites. We found that natural regeneration of tree species on the limestone hill was difficult because of the prevailing combination of physical and biological factors. The influence of these factors was species dependent, and the magnitude of effects varied across forest stands.

• Journal of agriculture & life science
• /
• v.43 no.6
• /
• pp.19-27
• /
• 2009

This study was carried out to obtain the basic model to estimate damage degree from the correlation analysis between forest fire and site environment factors and to clarify the restoration trends thorough multi-temporal survey by observing species diversity followed by various treatments at damaged forest area over time. From the derived model, the damage degree of forest fire was higher in the area of dense coniferous stands composed of simple story at the elevation of about 100m and 200m, and on steeper slope area over 30 degree. As results of this study, fire damaged trees are needed to cut down and a mixed stand with deciduous and coniferous species from the same area is desirable for the future species composition on fire damaged forest. Thus, site characteristics, local species, and mixed stands are the main consideration to enhance the vegetation recovery.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.2 no.1
• /
• pp.38-47
• /
• 1999

The mixed rural city is adjusting to change by urbanization. The recent landcover change in mixed rural city is an important factor that changes structure and function of regional ecosystem. Landscape ecology is an integrated ecology widely available for environmental science such as nature conservation and sustainable land-use planning. As the concern about environmental quality rises, many studies are trying to create and conservate for biotop. The creation of biotop is related to the plan and management of the effective landuse because the important factor to change the structure and function of ecological area in the country. This study was carried out to establish the foundation of the landuse plan to analyze the change of landuse and to plan the scheme in creating biotop and landuse. We used the approach of ecological landscape and using landscape indices with RS(Remote Sensing) and GIS(Geographic Information System) technology, spatio-temporal variations of areas and distribution of forest patches were examined in the Sunghwan in Chonan from 1985 to 1996. A result of this study showed that the area of forest and paddy decreased by urban sprawl. The size of patch in the forest and agriculture had been smaller and irregular form, heterogeneity of size of forest and agriculture patches within sub-basin was increased, pattern of forest and agriculture patches decreased the corridor and network from 1985 to 1996.