• Journal of Forest and Environmental Science
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• v.16 no.1
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• pp.17-33
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• 2000

The construction of a public cemetery in Kangnung city includes terraced graveyard with cutting or banking in mountain which has severe altitude differences with a slope of $30^{\circ}$. Therefore, there are scattered cutting and banking sections with vertical height more than 15m. Especially, if the slope failure or the loss of a graveyard happens after graveyard establishment due to surface flow and inflow around. it is difficult to repair, causing serious public censure. Accordingly, revegetation works were examined that need protection of slope. The specific content of the study was the selection of slopes requiring special care through blueprint and field investigation. the measurement of the physical property of slope and the situation of vegetative growth, the investigation of vegetation in slopes and the selection of vegetation. and the analysis of soil condition of slopes and the physical condition of slope sediment. On the basis of investigations some alternatives were proposed.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.515-521
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• 2013

The objective of this study was to estimate the changes of stand structure before and after applying the three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. This study has been conducted in the natural deciduous forests in Pyeongchang of Gangwon Province, Korea. Nine permanent sampling plots of 0.09 ha were established in the forests and each of the three silvicultural treatments was applied to three sampling points. Some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after applying the silvicultural treatments. In this study, a competition index was used to analyze the differences among structures of stands managed by three different silvicultural treatments. Hegyi's distance-dependent competition index was estimated and compared to analyze the differences of stand structures among the stands before and after silvicultural treatments. A method using a height angle $50^{\circ}$ from the base of the subject tree was adopted as the selection method of competitor trees. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand structure among the stands. The results revealed that competition status among trees in the stand seems to be improved after applying the silvicultural treatments. There are significant differences in the competition index between before and after silvicultural treatments for each stand. According to the evaluation of competition index, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments.

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.101-113
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• 2007

A landslide was occurred due to soil cutting for construction to expand the Donghae express highway in Dong-hae-City, Korea. The total area of the landslide was about $9,550m^2$ with 100 m of width and 87m of height. The landslide was occurred due to the internal factor of the unstable geological structure including the clay layer and the external factor of continuous heavy rainfalls. As the result of field instrumentation during the landslide, the horizontal displacement of the slope ground increases with increasing the accumulated rainfall by continuous rainfall during the rainy season. Also, the depth of sliding failure was decided by the horizontal displacement distribution during landslide occurrence. It makes sure that the horizontal displacement starts from the depth of sliding failure and the depth of sliding failure matches well with the location of the clay layer. As the slope stability analysis using Bishop's Simplified Method at the landslide area, the safety factor of slope during the rainy season was 0.53. This safety factor of slope was enough to trigger the landslide at this area. The depth of sliding failure obtained by analytical method matches well with the depth of the clay layer.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.4
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• pp.73-85
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• 1991

Rhododendron mucronulatum for. albiflorum, native species is a shrub that has white flowers on May to June, and rare species endangered by people's rash digging or cutting. But its physiological ecological characteristics and propagation method are not being known at all. Therefore, this study was executed to utilize this species as the planting material for landscaping by analysing its habitat environment and growth form, and also experimenting its seed and vegetative propagation, and it field culture and utilization. The results are as follows; 1. The elevation, gradient and direction of this species were 295-1,350m, 10-36$^{\circ}$, northwest respectively. It was found that the species is shade-liking plant that grows under forest cover of average 51.33%. 2. The soil pH and water content of its habitat were 5.4, 25.41% respectively. The organic matter content was 6.29% that was higher than 3.2%, the average organic matter content of forest soil in Korea. 3. Representative plant community within which this species was living was Quercus mongolica community, and its main neighboring species were Lindea obtusiloba, Fraxinus sieboldiana, Rhus trichocarpa, Rhododendron Schlippenbachii, Rododendron mucronulatum. 4. The leaf length and width of this species were 39.18mm, 12.60mm respectively. This result showed that generally its leaf size was larger than that of R. micranthum, R. yedoense var. poukhanense and R. mucronulatum var. ciliatum and smaller than that of R. mucronulatum and R. schlippenbachii. 5. The whole size of its pollen was, as 59${\times}$61$\mu\textrm{m}$, the largest of plants of Rhododendron family including R. mucronulatum and R. mucronulatum var. ciliatum. 6. The result of seed germination experiment at intervals of 5$^{\circ}C$ from 15$^{\circ}C$ to 30$^{\circ}C$ presented the highest germination rate of 94.7% at 20$^{\circ}C$ numerically, but high percent germination at all temperature levels without significant difference. And the seed of this plant proved to be sun-liking seed at requiring dormancy in germination. 7. Through seed germination experiment by treatment of growth regulators such as GA. Thiourea and Kinetin under dark condition, it was found that the effect of GA treatment on germination increase and acceleration was the highest. 8. In greenwood cutting, rooted rate by treatment of various concentration of IBA and NAA on clay and vermiculite bed was not wholly high, but 100ppm plots of both IBA and NAA of clay bed showed relatively good rooted rate. 9. As result of field culture experiment for finding out optimum growth temperature and light intensity, growth conditions such as height, number of leaves, fresh weight and chlorophyll contents were the best at night/day temperature of 20/25$^{\circ}C$ and under 1/2sun. Also, the photosynthetic rate was the highest at 25$^{\circ}C$. Accordingly, it was found that optimum temperature and light intensity for growth of this plant are 25$^{\circ}C$ (day temperature), 50% of natural light respectively.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.613-621
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• 2014

This study was conducted to estimate the changes of stand diversity before and after applying three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. Data were collected in the natural deciduous forests in Pyungchang of Gangwon Province, Korea. Nine permanent sampling plots of 0.09 ha were established in the forests and the each of silvicultural treatments was applied to three sampling plots, respectively. Some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after the silvicultural treatments. In this study, two different indices related to each of stand diversity indices such as contagion, DBH-difference, height-difference, and mingling were estimated and compared to analyze the differences of stand diversity among the stands before and after silvicultural treatments. As a result, total eight stand diversity indices were used to analyze the differences among structures of stands managed by three different silvicultural treatments. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand diversity among the stands. The results revealed that stand structures seem to be improved after applying the silvicultural treatments. There are significant differences in the stand diversity indices between before and after silvicultural treatments for each stand. According to the evaluation of stand diversity indices, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.297-304
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• 2012

The objective of this study was to estimate the changes of stand structure before and after applying the three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. This study has been conducted in the natural deciduous forests in Pyungchang of Gangwon Province, Korea. Three permanent sampling plots of 0.09 ha were established in the forests and the three silvicultural treatments were applied in 2008. For this study, some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after the silvicultural treatments. In this study, four stand structure indices were used to analyze the differences among structures of stands managed by three different silvicultural treatments. Contagion index, DBH-difference index, height-difference index, and mingling index were estimated and compared to analyze the differences of stand structures among the stands before and after silvicultural treatments. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand structure among the stands. The results revealed that all of the stand structure indices seem to be increased after applying the silvicultural treatments. There are significant differences in the stand structure indices between before and after silvicultural treatments for each stand. According to the evaluation of stand structure indices, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments. For attaining the specific goal of each stand types acquired by different silvicultural treatments, the frequencies and amounts of additional practices should be decided based on the changes of stand structure as time passed.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.388-394
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• 2007

To product the edible fresh shoots of Sedum sarmentosum in summer season, 4 local strains were cultivated with cutting propagation under 0, 30, 50, 70, 90% shading. Effect of shading on shoot growth, leaf chroma value, SPAD value, and bitterness were investigated at 35 days after cutting. Plant height, the number of node and leaf stem diameter in $30{\sim}90%$ shading were increased than in the control, and Pohang local strain had little-overgrowth shoot, thicker stem, a few brenches per shoot, and larger leaf compared to the other local strains. Fresh and dry weight under shading were increased than in the control, dry weight of pohang local strain was highest in 50% shading. Hunter L and b values were decreased out of proportion to higher shading rate. SPAD value in $50{\sim}90%$ shading was significantly lower than in the control. The bitterness of fresh shoot was decreased out of proportion to higher shading rate. In Summer season, producing the fresh shoot of S. sarmentosum was excellent in 50% shading, and Pohang local strain among 4 local strains was more stable and good in yield and quality under shading.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.513-520
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• 1991

The objective of experiment was to investigate the effects of seeding rate on forage yield and feed value, and to clarify the optimum seeding rate of rye in middle west area when cultured in paddy field. The field experiment treated with 5 levels of seeding rate was carried out at Yesan area in 1989. The plant height and the number of tillers per m' were increased but the dry matter rate was decreased as seeding rate increased. The fresh and dry weights of rye plant were increased as seeding rate increased. The highest yield was obtained from the harvest of May 15 and 25 in Yesan area. The TDN content and RFV were decreased by the increased seeding rate and delayed cutting date. The highest TDN yield was obtained from the seeding rate of 18kg/l0a and the next highest yield was obtained from the 23kg and 28kg/l0a seeding rate. The content of ENE, NEL, NEM, and NEG was decreased by the increased seeding rate and delayed cutting date. The highest ENE and NEL yields were obtained from the seeding rate of 23kg/l0a and May 15 harvest. The highest NEM and NEG yields were obtained from the seeding rates of 18kg/l0a and May 15 harvest, and of 18-28kg/l0a and May 5 harvest, respectively.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.195-204
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• 1999

To improve nut production and timber quality in a plantation, crown shape controls were suggested for Korean white pines (Pinus koraiensis) under age class III through the analyses of the crown shape controls for seed orchard trees in several species, of crown status of controlled and uncontrolled trees in a Korean white pine seed orchard, and of growth characteristics of plantation trees under age class III. For nut production from the small trees less than 8 m, modified leader type can be applied by cutting the central leader and all branches below 1 m and keeping 4~5 nodes with 3~4 whorled branches a node locating 1 m apart. Trees with a 4~8 m long trunk below the first living branch are shaped into trees for nut and timber production, which have a 4~8 m long knotless stem and a modified leader type crown with 4~5 nodes with 3~4 whorled branches a node at a distance of 1 m. Trees, showing the first living branch at or above 9 m from the surface, are pruned severely for timber production and result in a central leader type containing two fifths of the initial crown. It is advisable to remove the leader and the branches when collecting cones or after/during October to take advantage of easy labor and little resin while cutting. After stem cut, branches showing apical dominance are to be cut to control height when necessary. The removal of the uppermost node may be needed to control the crown shape several years after the initial stem-cut.

• Journal of Korean Society of Forest Science
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• v.82 no.3
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• pp.227-234
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• 1993

This study was carried out to seek for a most effective hastening method of seed germination by Pon-Pon treatment and asexual multiplication method by cutting in Zanthozylum piperitum. The results obtained in this study were as follows : 1. Cold moist stratification under the ground accompanied with Pon-Pon treatment was shown 74.3% of seed germination, which was the most effective one among pretreatment methods with significance at 1% level. 2. Height growth was shown continuous growth pattern and the maximum growth was shown during the period 1 July to 31 July, which corresponds 40.3% of total annual growth. 3. Although no noticeable difference among the kind of plant growth regulator in the rooting rate, there was difference among concentrations with significance at 1% level. 4. In the case of number of primary roots and T/R rate of rooted cuttings, treatment of plant growth regulators was significantly superior to control. 5. T/R rate in rooted cuttings was a high negative correlation (r=-0.7164) with the number of primary roots.