• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.251-258
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• 2007

Airborne Lidar (light detection and ranging) can be an effective alternative in forest inventory to overcome the limitations of conventional field survey and aerial photo interpretation. In this study, we attempt to develop methodologies to identify individual trees and to estimate tree height from airborne Lidar data. Initially, digital elevation model (DEM) data representing the exact ground surface were generated by removing non-ground returns from the multiple-return laser point clouds, obtained over the coniferous forest site of rugged terrain. Based on the canopy height model (CHM) data representing non-ground layer, individual tree heights are extracted through pseudo-grid method and moving window filtering algorithm. Comparing with field survey data and aerial photo interpretation on sample plots, the number of trees extracted from Lidar data show over 90% accuracy and tree heights were underestimated within 1.1m in average at two plantation stands of pine (Pinus koraiensis) and larch (Larix leptolepis).

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.41-54
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• 2011

Tree roots can enhance soil shear strength and slope stability. However, there has been a limited study about root reinforcement of major tree species in Korea because of some experimental difficulties. Thus, this study was conducted to analyze the performance of Japanese larch (Larix kaempferi) and Korean pine (Pinus koraiensis) which are two common plantation species in Korea. Profile wall method was used to measure the spatial distribution of root system and its diameter within 15 soil walls of Japanese larch stand and 13 soil walls of Korean pine stand in Taehwa University Forest, Seoul National University, Korea. Root tensile properties of each species were assessed in the laboratory, and root reinforcements were estimated by Wu model. The study observed that the number and cross-sectional area (CSA) of root in both species could tend to decrease with soil depth. Especially, CSA were well-fitted to exponential functions of soil depth. Mean root area ratios (RAR) were 0.03% and 0.10% for Japanese larch and Korean pine, respectively. Estimated root reinforcement from Wu model were, on the average, 4.04 kPa for Japanese larch and 12.26 kPa for Korean pine. Overall, it was concluded that root reinforcement increased the factor of safety (Fs) of slope for small-scale landslide as the result of two-dimensional (2-D) infinite slope stability analysis considering vegetation effects.

• Korean Journal of Ecology and Environment
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• v.47 no.3
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• pp.135-145
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• 2014

The mountain forest vegetation of Gyebangsan (1,577 m) in Odaesan National Park is classified into deciduous broad-leaved forest, mountain valley forest, coniferous forest, subalpine coniferous forest, subalpine deciduous forest, plantation forest, and other vegetation which includes Actinidia argute community and agricultural land. As for the number of communities distributed in the each forest vegetation which were categorized by the physiognomy classification, deciduous broad-leaved forest had 33 communities, mountain valley forest 41 communities, coniferous forest 8 communities, subalpine coniferous forest 4 communities, subalpine deciduous forest 2 communities, plantation forest 6 communities and other vegetation 4 communities. Regarding the distribution rate of communities in the vegetation, in the deciduous broad-leaved forest. Quercus mongolica community accounted for 80.226% with $30,909,942.967m^2$, followed by Quercus variabilis community of 2.771% with $1,067,479.335m^2$. 55.463% of deciduous broad-leaved forest in the Gyebangsan had Quercus mongolica as a dominant or second dominant species. In the mountain valley forest, Fraxinus rhynchophylla - Juglans mandshurica community accounted for 10.955%. And there were ten mixed communities having Fraxinus rhynchophylla and upper layer at a similar level of coverage, taking up 32.776%. In the coniferous forest, Pinus densiflora and the community living with Pinus densiflora accounted for 100%, showing that the coniferous forest has the community with Pinus densiflora as a dominant species at upper layer. For other vegetation, subalpine coniferous forest had a total of four communities including Abies holophylla - Quercus mongolica community, and accounted for 4.980% of vegetation area of Odaesan National Park. Two communities including Betula ermani - Cornus controversa community were found in the subalpine deciduous forest, taking up 0.006% of total vegetation area of Odaesan National Park. Regarding plantation forest, Larix leptolepis was planted the most with 51.652%, followed by Betula platyphylla var. japonica with 38.975%, and Pinus koraiensis with 7.969%. These three species combined accounted for 98.565%. In conclusion, the forest vegetation found in the Gyebangsan of Odaesan National Park has Quercus mongolica as a dominant species at the top layer. A lot of other communities related with this species are expected to be quickly replaced due to vegetation succession and climatic causes. Therefore, Quercus mongolica is expected to become the main species in the deciduous broad-leaved forest, Fraxinus rhynchophylla, Juglans mandshurica and Fraxinus mandshurica in the mountain valley forest. Around the border line between deciduous broad-leaved forest and mountain valley forest, highly humid valley area is expected to be quickly taken up by Cornus controversa and Fraxinus mandshurica, and the slope area by Quercus mongolica. However, in the subalpine coniferous forest, the distribution rate of deciduous broad-leaved trees is expected to increase due to climate warming.

• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.208-219
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• 2020

Forest thinning brought the large variation to forest ecosystem including environment and animal. Our study was result of long-term monitoring for ground-dwelling arthropod communities after thinning in forest ecosystem. In this study, we conducted field study on plantation forest in Chuncheon, Korea in 2018, and compared with previous study data (2006 and 2008). We found that the effect of thinning was still existent 10 years later from thinning with difference of habitat environment(depth of ground organic matter, coverage rate of ground vegetation and canopy). And ground-dwelling arthropod communities showed changes of abundance and taxa at the study area and thinning conditions. Ground-dwelling arthropod communities in 2018 were dominant in the order of Diptera, Hymenoptera, Coleoptera (Insecta), Araneae (Arachnida) and Collembola (Collembola). Among the conditions of thinning, Araneae (Arachnida), Coleoptera and Hymenoptera (Insecta) showed amount of abundance in heavy thinning. And Collembola (Collembola) and Diptera (Insecta) were most common in area of light thinning. In 2018 ground-dwelling arthropod communities, abundance of Diptera and Coleoptera (Insecta) and Isopoda (Crustacea) were decreased although Hemiptera and Orthoptera (Insecta) were increased than 2008 arthropod communities. Arthropod communities in 2018 were more similar with those in 2008 (after thinning) than with those in 2006 (before thinning).

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.725-740
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• 2014

To figure out the vegetation situation in the ridge of the Naknam-Jeongmaek, six intensive survey sites were selected considering environmental factors and human interferences, 132 quadrats (area $100m^2$) were installed to survey appearing species of trees and major environmental factors, and the characteristics of vegetation structures were analyzed. The surveyed plots were divided into six groups according to the analysis of classification by TWINSPAN; Quercus mongolica-Q. variabilis community, Pinus densiflora-Q. dentata community, Chamaecyparis obtusa community, Q. mongolica-P. densiflora community, P. densiflora-P. thunbergii community, P. koraiensis community, Rhododendron spp.-Lespedeza cyrtobotrya community. P. densiflora-Q. dentata community, Q. mongolica-P. densiflora community, and P. densiflora-P. thunbergii community are expected to be succeeded by deciduous oaks because the power of deciduous oaks is strong in their lower layer. C. obtusa community, P. densiflora community, and Rhododendron spp.-L.cyrtobotrya community are artificial forests that were artificially formed and are expected to be maintained in the current state for some time because the dominance value of planted species of trees is high. Most vegetations in Naknam-Jeongmaek were secondary forests or artificial forests formed for forest tree production and forestation for erosion control. In particular the top regions and hilly sections of the mountain were mostly dominated by deciduous oaks such as Q. mongolica, Q. variabilis showed some P. densiflora community competing with deciduous oaks. On the other hand, low sections and regions adjacent to the city showed severe artificial interference since exotic species such as P. thunbergiil, C. obtusa, P. koraiensis, and Rhododendron spp. were planted.

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.35-50
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• 1999

The relationship between floristic composition and soil environmental conditions was investigated in the forest vegetation of Mt. Paekun. The forest vegetation unit of Mt. Paekun was divided into six plant communities by Zurich-Montpellier method, such as Quercus mongelica community (Typical subcommunity, Rhododendron schlippenbaohii subcommunity), Q. variabilis community, Fraxinus rhynchophylla community, Pinus densiflora community, Larix Eeptolepis community and Pinus koraiensis community. Q. mongolica community group was distributed at the altitude over 500 meter, Q. variabilis and P. densiflora communities appeared on the southwestern slope at the altitudes of 600 ~ 700 m and 290 ~ 700 m. However, L. leptolepis and P. koraiensis plantation were distributed at lower altitude, on hillside or around homestead. The DBH class distribution of dominant species in each community showed that Q. mongolica had 10.9 individuals/a at 6~10 cm class, Q. variabilis 2.5 individuals/a at 11~15 cm class, P. densiflora 1.8 individuals/a at 26~30 cm class, F. rhynchophylla 3.3 individuals/a at 2~5 cm class, and L. leptolepis 5.9 individuals/a at 11~ 15 cm class. Q. mongolica and Q. variabilis communities showed a stable bell-shaped pattern of distribution. The contents of organic matters and soil water, and cation exchange capacity of the soil increased, and the pH decreased as the altitude gets higher increased altitude at the each communities. The contents of the soil water and organic matters of the forest soil collected in Q. mongolica community were in the 17.81% to 51.20% and 5.51% to 14.90%, respectively. These tendency is similar to the contents of N, P and K, but those of Ca, Mg, and CEC was lower than in other communities. Cation exchange capacity was suspected to be correlated to the pH. The hypothetical successional sere of the forest vegetation of Mt. Paekun is as follows: Pinus densiflora community longrightarrowQ. variabilis community longrightarrowQ. mongolica community.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.1
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• pp.58-68
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• 2015

This study compares the wind stability of Larix kaempferi (Lamb.) Carr., Pinus koraiensis Sie. & Zucc. and Abies holophylla Maxim. to understand and inform wind risk management of these plantation trees at Daegwallyeong, Korea. Temporary square plots of $20m{\times}20m$ ($400m^2$) were laid out, and DBH (Diameter at Breast Height) and height for trees greater than 10 cm in DBH were measured by species. A total of 15 plots with 5 plots each in L. kaempferi, P. koraiensis and A. holophylla stands were sampled at random. Among the species, A. holophylla and P. koraiensis have comparatively lower h/d (Height/DBH) ratios than L. kaempferi. These results indicate that the former two species are more wind firm than the latter species. About 9% of the L. kaempferi trees have higher h/d ratios than the critical threshold limit 80. These trees are vulnerable to wind damage and should be removed in the next thinning regime. The analysis of variance detected a significant difference (p < 0.05) in the h/d ratios and Gini coefficient indicating species differences and DBH size variation, respectively. Gini coefficient was 16.4% in A. holophylla, 15.9% in P. koraiensis and 14% in L. kaempferi stands indicating limited DBH size variation. Lower h/d ratios are attributed to thinning in these stands and tree morphological differences. To increase wind firmness, low thinning should concentrate to remove trees with the h/d ratio above 80 coinciding at the time of stand distinction phase. Forest managers and practitioners should measure and maintain h/d ratios of trees below the critical threshold limit of 80 through stand density management. Variable density thinning approach should be tested to increase tree DBH sizes of the even-aged stands.

• Journal of Korean Society of Forest Science
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• v.47 no.1
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• pp.37-43
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• 1980

This study have done to get the basical information that would be useful to make the ecological planting, selection of suitable species and weeding plan by the relation between the leading shoot elongation of several species and the climatic factors in the plantation. Sampling measurement have been done in the trial forest of Korean German Forest Management Project located in Joil-ri, Samnam-myeon and Ichcon-ri, Sangbug-myeon, Ulju-gun. The former is in lowland at 100m latidude and the latter is in highland of 600 m latitude. The elongation of leading shoot has been measured in the plantation with 10 days interval from the beginning of March in 1979 and the climatic datas has gotten in the weather station closed to the plantation. 1. The change of air temperature and rainfall in each measuring site is like Fig 1. and 2. The similar temperature in 600 m high latitude is coming about 10 days latter than 100 m latitude. 2. Genus pine as Pinus thunbergii, P. rigida, P. rigitaeda. P. koraiensis and P. taeda begin their leading shoot growth during March and air temperature in that time is around $6^{\circ}C$. In highland their beginning of leading shoot elongation has been found out 10 days latter than lowland. However Abies, Larix and Picea has shown to open their leading shoot during May, 40 days late in comparing with genus pine, and then temperature is making around $15^{\circ}C$. But Cryptomeria, Chamaecyparis and Cedrus deodora has shown their leading shoot opening in March in lowland and May in high land. The reason of late opening, specially in highland, seems to be the influence of winter frost. 3. Most of leading shoot elongation of genus pine has finished during the end 10 days of April and May under range of air temperate $10^{\circ}C$ and $20^{\circ}C$ and other species has finished most of their elongation during the end 10 days of May and June with air temperature range of $18^{\circ}C$ to $20^{\circ}C$. So the suitable season of weeding works show to genus pine in May and other species in June. 4. The leading shoot growth of genus pine has started earlier and closed earlier too than other species and, when over than $20^{\circ}C$ air temperature, their growth is decreasing quickly. Pices abies as well show to be decreased suddenly in over than $20^{\circ}C$ temperature. Other species show the similar trend when over than $22^{\circ}C$. This reason is considered as high temperature of summer season. 5. Annual elongated days of leading shoot of Picea abies is 50 days, Abies hollophylla 70 days, and more than 85 percentage of shoot growth of Pinus koraiensis and Larix leptolepsis are growing during 70 dys as well. The shoot growing days of Chamaecyparis, P. rigida, P. rigitaeda, P. taeda and P. shunbergii show longer period as over than 120 days. 6. The shoot elongation times per year of Abies and Picea has closed as one times and Genus pine is continuring their elongation more than two times. But Cryptomeria, Chamaecyparis, Cedrus deodora and Larix show one or two times elongation depending on the measuring site. The reason of continuring elongation more than than two times seems to be influenced by the temperature in summer season except the genetical reason. 7. Depending on the above results, as the high temperature in summer season could give the influence to grow the leading shoot in the plantation, this would be the considering point on the ecological planting and selection of the suitable species to the slope aspect. The elongation pattern by the season show to be the considering point too to decide the the weeding and fertilizer dressing time by the species.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.125-135
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• 2022

In this study, growth changes of the diameter at breast height (DBH), height, basal area, volume, and biomass of Korean white pine (Pinus koraiensis Siebold & Zucc.) on a plantation were examined via long-term monitoring. In addition, this study was performed to provide the basic data for timber production in line with DBH class by comparing the growth of the relative DBH size. Growth characteristics according to DBH class were analyzed by categorizing trees into five classes based on sorted DBH rankings: class I (1%-20%; upper 20%), class II (21%-40%), class III (41%-60%), class IV (61%-80%), class V (81%-100%; lower 20%). A total class (0%-100%) was also used. Total increment and mean annual increment (MAI) were calculated using data from nine measurements taken over 39 years. Tree characteristics based on average values and stand characteristics based on unit area per hectare were examined. According to the total increments of variables, the differences in DBH, basal area, volume, and biomass among classes I-V increased over time, whereas the height difference did not continually increase. According to MAI, the maximum DBH value was 0.92 cm·yr^-1 at age 23 in class I, whereas the maximum value in all trees was 0.69 cm·yr^-1 at age 17. The maximum value of height MAI for class I was 0.52 m·yr^-1 at age 23, whereas that for all trees was 0.49 m·yr^-1 at age 20. In terms of basal area, volume, and biomass growth at tree-and stand-level, the maximum MAI of class I and all trees was not observed during the measurement period. Therefore, additional long-term monitoring data are required to determine the maximum MAI of the variables.

• Journal of Korean Society of Forest Science
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• v.80 no.1
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• pp.54-71
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• 1991

To classify and analyze the forest communities and their structures, the vegetation in Mt. Joghe was investigated from July, 1980 to August, 1989. The results obtained are as follow ; 1. A total of 750 kinds of vascular plant(49 orders, 122 families, 434 genera, 627 species, 1 subspecies, 111 varieties and 11 forma)were observed in Mt. Ioghe. The newly observed plant species were Dioscorea quingueloba, Spiranthes sinensis, Cephalanthera falcata, Angelica gigas, Clematis patents, Paeonia obovata, Hibiscus mulabilis, Ainsliaea acerifolia, Dictamnus dasycarpus, Cynachum ascyrifolia, Vaccinium koreanum, Erythrortium japonicum, Indigofera kirilowii (17species), Broussonetia kazinoki var, humillis, Euonymus, fortunei var. radicans, Juniperus communis var, nippnnica, Callicarpa japonica var. radicans, Joniperus communis var. rzipponica, Callicarpa japonica var. taquetii (4 varieties) and L indera obtusiloba for. billosum (1 forma). 2. The life spectrum of flora in Mt. Joghe was classified into $CH-D_1-R_5-e$ type. Distribution area was identical to Southern type by Nakai, Lee, and Yim. A few subtropical species were also observed. 3. Simpson's species diversity index(Ds) was 0.9 and Shannon-Weiner's diversity index (H') was 1.004. These indice suggest that the vegetation in Mt. Joghe is of complicated forest communities. 4. Pte-Q was 1.81 which was higher than the nationwide mean of 1.68. Urbanization Index (UI) was 28.75 for naturalized plant species, and 17.49 for exotic woody plant species, which were similar to those of Mt. Baekun and Mt. Naejang. 5. The forest vegetation of Mt. Joghe was grouped in 3 vegetation types : 7 natural plant Communities dominated by Quercus serrat, Quercus acutissima, Quercus variabilis, Carpinus laxiflora, Pinus derasiflora and Platycarya strobilacea, 8 substitutional plant communities Styrax japonica, Stewartia koreana, Lindera erytlrrocarpa, Zelkova serrata, Rhtrs chinensis, Controversa, and Frzrxirtus manrlshurica, and 7 plantation Communities composed of Pinus koraiensis, Pinus rigida, Magnolia nbnvata, Chamecyparis obkrsa, Larie ieptolepis, Castanea crenata and Cryptomeria japonica. 6. Actual vegetation maps and profile diagrams were made by phytosocialogical classification. 7. As the important and unique species in Mt. Joghe, Lindera sericea, Penicaria tilitorme, Hex macropoda, Hex macropoda for. pseudo-macropoda, Steroartia koreana, Adenopkora palustris and Corylop.,is coreana, which were also seported by Lee(1977), Kim and Yark(1989), were identified and Vaccinium coreanum, Cremastra appendiculinium, Juniperus comminis van. nipponica, Cephalanthera falcata, Broussortetia kazinoki var. humilis, paeonia obovata, Deutzia prunifolia, Dictamnus dasyarpus, Angelica gigics and Bupleurum falcatum were odditionally observed.