• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.699-706
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• 2001

This study was conducted to evaluate the effectiveness of basic oxygen furnace (BOF) slag as soil conditioner in a nursery and two natural forests. The BOF slag was applied at rates of 0, 4, 8, and 12 t/ha for seedbed nursery of three tree species-Pinus densiflora, Larix leptolepis and Amorpha fruticosa; and 0, 10, 20, and 40 t/ha for Pinus densiflora natural forests located at two sites. In case of the nursery study, the significant increase in soil pH and contents of Ca, Mg, $SiO_2$, Fe and Mn was noticed after six months of the BOF slag application. Dry weight of Pinus densiflora seedlings with BOF slag treatments was lower compared with that of control. There were no significant differences among treatments in dry weight of Larix leptolepis seedlings. Dry weight of Amorpha fruticosa seedlings, which are deciduous species and grow rapidly at seedling stage, increased significantly and T/R ratio decreased as BOF slag rate increased. The differences of effects of BOF slag application on the seedlings of tree species may be attributed to the differences of optimum pH range of the species. In Pinus densiflora natural forests, there were no significant differences in soil pH and contents of $SiO_2$, Fe and Mn among the treatments, but these values became higher as BOF slag rate increased. Contents of Ca in soil became significantly higher as BOF slag rate increased. There were no significant differences among treatments in net production of mature Pinus densiflora trees, but BOF slag rate of 10ton/ha showed the highest net production. Young Pinus densiflora trees at the plots of BOF slag rate of 10 t/ha showed significantly higher root collar diameter growth rate and twig net production than those of other treatments. It may be given as a conclusion that BOF slag application in nursery and forest soil increased soil pH and contents of Ca, $SiO_2$, Fe and Mn in soil and they showed the ability of BOF slag to be used as a soil conditioner in strongly acid soil.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.1-9
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• 1994

This study focuses on forest fires attributed to cigarette light, the main source of wild fires, by examining the characteristics of the fire types. It aims to present useful data for preventive measures. Statistics show that the average length of cigarette butts left after smoking is 30mm excluding filter for domestic cigarette smokers. Also the average thickness of litter layer in forests is 58.2mm throughout the nation. The value varies according to how often leaves were trodden by hikers : the accumulation amount of Mt. Sunchi. which is relatively protected from human disturbances, is 29.6% more than that of Mt. Kye-Ryong National Park. Aged trees such as Pznus rzgidu, Quercus acutissima and Larix leptolepis have relatively large inflammable contents, 2.43kg in 15 year-old stand and 2.55kg in 10 year-old stand. This study found out the following fact with regard to the start of lighting and the out-break of fire. Fire breaks out within five minutes in the sample(C), in which Zoysza gaponica and Populus X tomentiglandulosu has been tramped when the sample has 2~6 percent of moisture contents. Coniferous trees such as Pinus rigida and Larzx leptolepis do not burn easily while leaving charcoal. In contrast, deciduous trees with Zoysia japonzca and Populus X tomentiglandulosu are quick to catch fire. As a result of the experiments, it is proved that cigarette light is a very dangerous cause of wild fire especially for dry grass like Zoysia gaponica.

• Korean Journal of Environment and Ecology
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• v.12 no.3
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• pp.236-241
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• 1998

This study was to compare soil characteristics among Quercus mongolica communities that characterize the boreal-temperate deciduous forest in Korea. The classification of Quercus mongolica community and soil sampling were carried in Mt. Odae and Mt. Jungwang in Kangwondo from April of 1991 to October of 1994. The study area was classified as 5 Quercus mongolica communities with Braun-Blanquet method as follows; Quercus mongolica - Abies nephrolepis, Quercus mongolica - Acer pseudosieboldianum, Quercus mongolica - Lindera obtusiloba, Quercus mongolica - Acer mandshuricum, and Quercus mongolica - Carpinus cordata communities. Quercus mongolica - Abies nephorolepis community had the most shallow depth of A horizon(5cm) among communities, and root penetration was mainly from 0 to 10cm soil depth, and they had a dry soil moisture condition. Depth of A horizon of Quercus mongolica - Lindera obtusiloba and Quercus mongolica - Acer mandshuricum communities was about 20cm, and root penetration was mainly from 0 to 20cm soil depth, and they had a slightly dry soil moisture condition. Quercus mongolica - Acer mandshuricum, and Quercus mongolica -Carpinus cordata communities had the deepest depth of A horizon(35cm) and root was well developed over 45cm, and they had a moderately-slight dry soil condition. The soil organic matter, total N, exchangeable Ca, Mg and K concentration and CEC was the greatest in Quercus mongolica-Acer mandshuricum community and Quercus mongolica-Carpinus cordata community among communities. Quercus mongolica - Abies nephyolepis community had the smallest soil organic matter, total N, and CEC among communities. There were large differences among Quercus mongolica communities by soil properties and the result may be due to different habitat positions in the landscape among communities.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.2
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• pp.61-71
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• 2009

Most deciduous trees in temperate zone are dormant during the winter to overcome cold and dry environment. Dormancy of deciduous fruit trees is usually separated into a period of rest by physiological conditions and a period of quiescence by unfavorable environmental conditions. Inconsistent and fewer budburst in pear orchards has been reported recently in South Korea and Japan and the insufficient chilling due to warmer winters is suspected to play a role. An accurate prediction of the flowering time under the climate change scenarios may be critical to the planning of adaptation strategy for the pear industry in the future. However, existing methods for the prediction of budburst depend on the spring temperature, neglecting potential effects of warmer winters on the rest release and subsequent budburst. We adapted a dormancy clock model which uses daily temperature data to calculate the thermal time for simulating winter phenology of deciduous trees and tested the feasibility of this model in predicting budburst and flowering of Niitaka pear, one of the favorite cultivars in Korea. In order to derive the model parameter values suitable for Niitaka, the mean time for the rest release was estimated by observing budburst of field collected twigs in a controlled environment. The thermal time (in chill-days) was calculated and accumulated by a predefined temperature range from fall harvest until the chilling requirement (maximum accumulated chill-days in a negative number) is met. The chilling requirement is then offset by anti-chill days (in positive numbers) until the accumulated chill-days become null, which is assumed to be the budburst date. Calculations were repeated with arbitrary threshold temperatures from $4^{\circ}C$ to $10^{\circ}C$ (at an interval of 0.1), and a set of threshold temperature and chilling requirement was selected when the estimated budburst date coincides with the field observation. A heating requirement (in accumulation of anti-chill days since budburst) for flowering was also determined from an experiment based on historical observations. The dormancy clock model optimized with the selected parameter values was used to predict flowering of Niitaka pear grown in Suwon for the recent 9 years. The predicted dates for full bloom were within the range of the observed dates with 1.9 days of root mean square error.

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.649-663
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• 1998

The clarify the ecological properties, and to predict change of understory vegetation of mt. Nam Park, population dynamics and interspecific competition of D. smilacinum and D. viridescens, which grow in understory of deciduous broad-leaved forest and pseudo-annuals, were studied from May 20 to May 30 1998. The depth of litter layer, soil moisture content, soil organic matter and soil texture were surveyed in 18 populations (15 D. smilacinum populations and 3 D. viridescens populations). Mean litter layer of d. smilacimum population was thinner than that of D. viridescens populations). Mean litter layer of D. smilacnum population was thinner than that of D. viridescens population. The contents of soil moisture and organic matter of D. smilacinum population were lower than that of D. viridescens population. The D. smilacinum growed in broad range of soil texture but D. viridescens in loamy soil. Because D. smilacinum could tolerate more broad range of soil moisture and soil texture than D. viridescens, the former covered the herb layer in earlier stage and the latter introduced in later stage when rhizome could grow easily. The numbers of individual in two marginal parts were smaller than that in center in same D. smilacinum patch. And the total numbers of individuals grown in (10 ${\times}$ 10)cm were from 0 to 12. The rhizome (subterranean runner) weight, rhizome length, root weight, shoot weight, lea weight and leaf number per subquadrat (cell) increased along the number of individual, that is, increased from marginal part to center. But rhizome weight and rhizome length per individual were vice versa. Therefore, the individuals in marginal part reproduced longer and stronger asexual propagules than that in center. The distribution pattern of D. smilacinum was contageous and that of D. viridescens was random or regular. Therefore, population growth of former was independent on density and that of latter was dependent on density. The distributions of size-class showed normal curves in two population, but the curves based on data of total dry weight showed positive skewness and those of leaf number showed negative skewness The correlation coefficient (CC) values between the properties of each organ were high in two population and significant at 0.1% level. The CC values of D. viridescens were higher of the two. Therefore, the former allocated the energy to each organ stable. The rhizome depth of d. viridescens was 2 times deeper than that of D. smilacinum. And rhizome length and weight of D. viridescens were longer (2 times) or heavier (4 times) than those of D. smilacinum. The patch size of D. viridescens increased 60 cm per year and that of D. smilacinum 30 cm. On this results, the intrinsic increase velocity of d. viridescens patch was 2 times faster than that of d. smilacinum, therefore, on the competition, the former had an advantage over D. smilacinum. The reason why d. viridescens defeated D. smilacinum resulted from that the leaf area of former was 4 times broader than that of latter. in Mt. Nam Park, it was thought that two disporum Population would change with the 3 thpes of environmental change as followings. First, no human impact and increase of soil moisture content resulted in increase of D. viridescens population. Second, mild human impact and similar condition of soil moisture content resulted in slow increase or no changes of D. smilacinum and d. viridescens population. Third, severe human impact and dry condition resulted in decrease or vanishment of two disporum populations.

• Korean Journal of Environmental Biology
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• v.37 no.1
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• pp.109-118
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• 2019

This study was carried out to investigate the vegetation of wetland and terrestrial lands in Jangdo wetland conserved area in Korea and to analyze the characteristics of the vegetation changes in the recent years. From the plant community, there were evergreen broad-leaved forests of the Machilus thunbergii, Castanopsis cuspidata, and Machilus thunbergii-Castanopsis cuspidata communities. Moreover, there were deciduous broad-leaved forests of the Salix koreensis, Mallotus japonicus, Mallotus japonicus-Pueraria thunbergiana and Celtis sinensis communities. Additionally, there were shrub forests of the Rosa multiflora-Rubus hirsutus, grassland of Molinia japonica-Miscanthus sacchariflorus and Miscanthus sacchariflorus-Imperata cylindrica communities, and plantation forest of the Pseudosasa japonica community. The area of the wetland vegetation (15%) was much narrower than that of the terrestrial land vegetation (85%). Comparing these results with those of the past 10 years, the wetland plant communities decreased by one-third and the proportion of neutral or dry plant communities increased. In order to mitigate landization succession of the wetland and maintain native wetland vegetation in this area, the expansion of the Salix koreensis community must be controlled to a suitable scale. In addition, it is urgently required to remove the invasive non-wetland plants, such as Pseudosasa japonica and Pueraria thunbergiana.

• Journal of Wetlands Research
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• v.25 no.3
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• pp.196-204
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• 2023

Eleutherococcus gracilistylus is a designated rare plant by the Korea Forest Service, a deciduous broad leaf shrub native to the Gotjawal region, Jejudo. This study aimed to analyze the growth responses of E. gracilistylus to three environment factors such as light, moisture, and organic matter, and measure its ecological niche breadth. Based on these results, an attempt was made to identify suitable environmental conditions. E. gracilistylus exhibited increased above-ground length, leaf area, and plant leaf weight under intermediate conditions of light availability(L3, 50% of natural light), rather than very high or very low light conditions. Moisture availability and organic matter availability showed variations in growth responses in terms of leaf count and plant leaf weight. Under moisture availability, growth was favorable under or below intermediate conditions (M3, 240ml), while under organic matter availability, growth response was better above intermediate conditions (N3, 12%). Ecological niche breadth showed in the light factor(0.951), the moisture factor(0.977), and the organic matter content one(0.964). These results indicate that the preferred habitat of E. gracilistylus is somewhat shady, slightly dry, and has a lot of nutrients, and that the environmental factor that has the greatest impact on growth is the amount of light, which is considered to be a priority consideration for habitat management in its native area.

• Journal of Korea Foresty Energy
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• v.17 no.1
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• pp.8-22
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• 1998

The phytomass and productivity of the evergreen needle pines(Pinus densiflora and Pinus rigida) and of the deciduous broad- leaved oaks(Quercus acutissima, Quercus variabililis and Quercus mongolica) in the watershed forests of South Han River, central part of Korea was estimated by the allometry. The allometic relations between D$^2$H and dry weight of stem(Ws), branches(Wb) and leaves(Wl) of these forests were as follows: Pinus densiflora community : logWs=0.58482D$^2$H-0.42417 logWb=0.6234D$^2$H-1.2321 logWl=0.2247D$^2$H-0.09359 Pinus rigida community : logWs=0.9218D$^2$H-1.4692 logWb=1.0064D$^2$H-2.2278 logWl=0.6275D$^2$H-1.1715 Quercus acutissima community : logWs=0.96659D$^2$H-1.56975 logWb=0.86315D$^2$H-2.17944 logWl=0.79876D$^2$H-1.97137 Quercus variabilis community : logWs=0.4753D$^2$H＋0.20026 logWb=0.5725D$^2$H-0.92006 logW1=0.61649D$^2$H-1.4288 Quercus momgolica community : logWs=0.5526D$^2$H-0.1228 logWb=0.5188D$^2$H-0.9787 logWl=0.7754D$^2$H-2.6273 From the above formulae, the phytomass of Pinus densiflora was estimated to be much as 1,200,000 ton, Pinus rigida 610,000 ton, Quercus acutissima 289 ton, Quercus variabilis 2,800ton and Quercus mongolica 570,000 ton in the surveyed area, respectively. Accordingly, the phytomass of Pinus densiflora forest was occupied about 43.9 % in toto and was higher thanthose of other forests. The phytomass of watershed forests belonging to Degree 8 and Degree7 divided by degree of green naturality(DGN) was 74,000 ton and 2,000,000 ton, resfectively. Accordingly, the watershed forests in South Han River were mainly composed of Pinus densiflora and Quercus mongolica forests belonging to Degree 7.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.4
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• pp.183-189
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• 2000

This study was carried out to analyze ecophysiological responses for seedling of Quercus serrata, Quercus mongolica and Quercus variabilis that are the typical species of deciduous broadleaved forests in Korea. And executed experiments in the climatic control room to provide necessary information to ecological forest management and methods of natural regeneration through the analysis of seedling responses. The details of experimental analysis were growth processes of 4 months after seeding that vary with the condition of three light intensity[relative light intensity(RLI) 8%, 20%, 52%] and three soil moisture[water suction(WS) Ψ=100 hPa, Ψ=280 hPa, Ψ=330 hPa] gradient, growth factors after harvesting and the nutrition condition of leaves. The results of this study are followings: 1) Early growth was prosperous after germination for the species which have more weight of acorn. 2) The formation of lammas shoot was favourable with Q. variabilis and Q. mongolica. And the rate of the occurrence was the highest in the RLI 20%, and it was remarkably reduced in the RLI 8%. 3) As the height growth of seedling of all 3 species were greater in the RLI 20% and 8% than that of the RLI 52%, they showed strong shade tolerance. 4) The increase of light intensity promoted the diameter at root collar growth, and development of main and lateral roots with all 3 species. 5) It showed that the increase of light intensity in the experimental radiation condition raised special leaf area weight(mg/cm$^2$) and leaf area productivity(mg/cm$^2$). Consequently, these resulted in the increase of leaf thickness and total dry biomass per the unit area of leaf. 6) As the increase of light intensity, the minerals contents of leaves such as N, P and K were lowered, and the increase of soil moisture resulted in the increase of P, K, Ca and Mg.