• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.398-407
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• 2021

This study intended to identify causes of poor tree vigor in the Hanbando coastal forest by investigating its geographical environment, climate condition, soil physicochemical characteristics, and growth condition of Pinus thunbergii. It divided the forest into an area with poor tree vigor or dead standing trees and a control area with good tree vigor and examined them separately. The survey showed that stand density was significantly higher in the area with poor tree vigor. In contrast, the crown width in the area with good tree vigor was wider. The number of dead standing trees and the stand density showed a negative correlation. The stand density and diameter at breast height (DBH), tree height, crown height, and crown width also showed a negative correlation. The result indicated that, as the tree's stand density increases, the crowns of individual trees overlapped and the lower branches died. Then crown height and crown width decreased, and the number of leaves and photosynthesis was reduced, leading to lower tree height and weaker growth of breast diameter. As a result, tree vigor weakened, and combined with environmental pressures from the lack of moisture and nutrients in coastal soil and salty wind, P. thunbergii in coastal areas is expected to die massively. Although the causes of dead standing trees and poor tree vigor of P. thunbergii in the Hanbando coastal forest are complicated, poor management of adequate tree density in response to the growth of P. thunbergii is the primary cause. The secondary cause is external environmental pressures, including unfavorable soil conditions and salty and strong wind that obstruct the growth of P. thunbergii.

• Journal of Korean Society of Forest Science
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• v.24 no.1
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• pp.25-44
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• 1974

In the present paper I described the results of the observations made on the visual characteristics such as the annual ring width and summerwood percentage of Pinus koraiensis Sieb. et Zucc. grown at out university forest. The results of the study are as follows: Characteristics of annual ring width and summerwood percentage 1. The range of dispersion of annual ring width and summerwood percentage are respectively 0.5-6.5mm and 5-50% on the normal wood and its arithmetic mean values are each 3.0mm and 24% on all sample trees. 2. The values of annual ring width of heart wood are larger than that of sapwood but on the contrary the values of summerwood percentage of heartwood are smaller than that of sapwood. On the other hand variations of these values are distingushed on the heartwood. 3. The values of annual ring width due to the parts of stem with crown. with clear length and at bottom showed that the largest values are given at the parts of stem with crown. But on the contrary the summerwood percentage values are largest at the parts of stem at bottom on all sample trees. 4. The values of annual ring width and summerwood percentage depending on the stand sides are not obvious. Horizontal and vertical variations of annual ring width and summerwood percentage 5. It was recognized that horizontal (radial direction) variations of annual ring width and summerwood percentage indicated two different patterns (the region of large fluctuation and that of small fluctuation) in a tree stem. These boundaries are seemed to appear at the parts of 12-15 annual rings from pith. 6. According to the increase of height in tree the values of annual ring width increase but the values of summerwood percentage gradually decrease. 7. But vertical variations of annual ring width and summerwood percentage on the sapwood are divided into two different parts (region of increased or decreased upwards and that of remained constant in successive height) in a tree stem and these limits are seemed to appear at the 7m of height in trees. Relations between annual ring width and summerwood percentage 8. The modes of summerwood percentage related with annual ring width are seemed to appear almost in the definite range (10-25%). 9. The relations between annual ring width and summerwood percentage show a highly negatine correlation on all sample trees.

• Korean Journal of Environment and Ecology
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• v.4 no.1
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• pp.63-68
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• 1990

User's impacts on trail deteriorations and edge vegetation were studied in Sokri Mountain National Park in 1990. The entire width, bare width and maximum depth of trail as the trail condition were significantly greater on the more heavily used trail. Deteriorations of trail which were surveyed at the total of 52 were significantly different from those of non-deteriorated points. The dominant trees in the crown layer of trail edge are as follows. According as the altitude rises, the changes happen from Quercus serrata to Quercus variabilis, Pinus densiflora, and to Quercus mongolica at Joongsajaam course, and from Pinus densiflora, Quercus variabilis to Quercus mongolica at Birosanjang course. And Stephanandra incisa, Symplocos chinesis for. pilosa show high relative dominant value at Joongsajaam course, Lindera obtusiloba, Fraxinus sieboldiana show one at Birosanjang course.

• Ecology and Resilient Infrastructure
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• v.10 no.3
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• pp.51-63
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• 2023

Riverine tree management is crucial in realizing a balance between flood control and ecological preservation, which requires an accurate assessment of the impact of trees on river water elevations. In this study, eight different formulas for evaluating vegetation roughness considering the drag force acting on trees, were reviewed, and the characteristics and applicability of these methods were evaluated from a practical engineering perspective. The study compared the characteristics of vegetation roughness measurement methods for calculated roughness coefficients at different water depths and analyzed factors such as effects of tree canopy width, tree density and diameter, and tree stiffness coefficient, and water level estimation results. A comparison of roughness coefficients at the same water depths revealed that the Kouwen and Fathi-Moghadam formulas and the Fischenich formula yield excessive drag coefficients compared to other formulas. Factors such as channel geometry, tree diameter, and tree density showed varying trends depending on the formula but did not exhibit excessive outliers. Formulas considering the tree stiffness coefficient, such as the Freeman et al.'s formula and the Whittaker et al.'s formula, showed significant variations in drag coefficients depending on the stiffness coefficient. When applied to small- and medium-sized virtual rivers in South Korea using the drag coefficient results from the eight formulas, the results indicated a maximum increase in water level of approximately 0.2 to 0.4 meters. Based on this review, it was concluded that the Baptist et al., Huthoff et al., Cheng, Luhar, and Nepf's formulas, which exhibit similar characteristics and low input data uncertainties, are suitable for practical engineering applications.

• Korean Journal of Environment and Ecology
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• v.5 no.1
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• pp.91-103
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• 1991

Use impacts on environmental deteriorations of trail and campsite were studied in Chirisan National Park in 1991. The entire width, bare width and maximum depth of trail as the trail condition were significantly greater on the more heavily used trail. Trail conditions, especially altitude, entire width and maximum depth of deteriorated points which were surveyed at the total of 82 were significantly different from those of non-deteriorated points. On the ridge trail, the damaged are more severe than Class 4 reaches about 34,000$m^2$ and use impacts on campsite and deterioration were also accelerated. The dominant trees of the upper layer in trail edge vegetation are changed from Carpinus tschonoskii to Quercus serrata, Carpinus laxiflora and to Quercus mongolica, Carpins laxiflora at Hwaeomsa trail, and from Quercus serrata to Quercus mongolica at Piagol trail. Also Lespedoza maximowiczii, Symplocos chinensis, Deutzia prunifolia, Weigela Subsessilis appear as the dominant lower species at Hwaeomsa trail, L. maximowiczii, S. chinensis, Stephanandra incisa, Rhododendron schlippenbachii for Piagol trail.

• Korean Journal of Environment and Ecology
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• v.10 no.1
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• pp.49-57
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• 1996

To figure out the relation between the shade hours and the landscape tree growth in the apartment housing areas, the present sizes and planting positions of 4 tree species in Gwacheon-si apartment housing areas were surveyed. Then, shade hours were analyzed and the data were analyzed by simple linear regression method. As a whole, the R$^{2}$ was too low to generalize the regression equation. Therefore, it was presumed that the gravity of shade hours in landscape tree growth in this sample site was relatively lower than that of any other environmental factors. However, it was presumed that the characteristics of shade intolerant and tolerant tree were turned up, because Pinus strobus showed a low negative correlation with shade housm and Acer palmatum and Magnolia denudata showed a low positive correlation with shade hours generally. And, it was proved that the statistically significant cases were the tree diameter at root collar and tree sidth of Acer palmatum and tree width of Magnolia denudata with shade hours showing a low correlation coefficient less than 0.4.

• Korean Journal of Environment and Ecology
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• v.13 no.2
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• pp.118-128
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• 1999

우리 나라 남서부에 위치한 변산반도내에 자생하고 있는 꽝꽝나무군락지의 천이에 관한 장기적인 모니터링과 보전관리를 위한 기초자료를 제공하기 위하여 서식환경 및 생육실태 등을 조사 분석한 결과를 요약하면 다음과 같다. 꽝꽝나무군락의 분포면적은 270m2로성목 123그루와 치수 약 170그루가 자라고 있다. 꽝꽝나무군락지 내부에는 총 21과 31속 30종 6변종 1품종(총 37분류군)의 관속식물이 서식하고 있다. 꽝꽝나무 성목의 평균 수고는 1.0m, 평균 수관폭은 동서 방향 112.3cm 남북 방향 91.3cm이었다. 꽝꽝나무의 평균 엽길이는 10.2mm, 평균 엽폭은 6.9mm, 평균 엽병길이는 1.7mm 평균엽면적은 0.47$\textrm{cm}^2$로서 좀꽝꽝나무로 표기하는 것이 타당하다고 사료된다. 꽝꽝나무 성목은 모두 개화하였으며 꽃은 모두 암꽃이었다.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.12-20
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• 2008

Radial and vertical variations of relative crystallinity and crystallite width of cellulose within stems of three softwoods (Pinus densiflora S. et Z., P. koraiensis S. et Z, P. rigida Mill.) grown in Korea were examined by an X-ray diffraction method. The mean of relative crystallinity was 61.7% in P. koraiensis, 60.6% in P. densiflora and 49.4% in P. rigida. The degree of crystallinity in earlywood and latewood increased with the age from pith to about 10~15 years, and then remained almost constant value. The relative crystallinitiy of latewood was slightly higher than that of earlywood. The relative crystallinity in P. densiflora was a little lower at the base of stem, but no significant difference by height was shown in P. koraiensis and P. rigida. The crystallite widths in the stems were 2.8 to 3.0 nm, but were not significantly different in earlywood and latewood by height. In conclusion, the relative crystallinity appeared to be a useful index for separating juvenile wood from adult wood in the softwoods of P. densiflora, P. koraiensis, and P. rigida grown in Korea.

• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.241-251
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• 1994

Use impacts on environmental deteriorations were studied on the four major trails and a campsite of Tokyuksan National Park in 1993. The entire width, bare width, maximum depth and slope of trail as the trail condition were significantly greater on the more heavily used trail. Percentages of rock-exposed, deepening, root-exposed points as the deterioration types of trail which were surveyed at the total of 106 points were higher and trail conditions were significantly different from those of non-deteriorated points. On the Paekryon trail, the damaged area more severe than Class 4 reaches about 910$m^2$/km and the use impact and deterioration on campsites were accelerated. The dominant trees of the the upper and lower layer in trail edge vegetation could be Quercus serrata and Acer pseudo-sieboldianum for Paekryon trail, Q. mongolica and Tripterigium regelii for the other trails. A. pseudo-sieboldianum, Q. serrata, Rhus trichocarpa, Fraxinus sieboldiana, Lespedeza maximowiczii, Symplocos chinensis for Pilosa were classified for tolerant species to use impacts.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.168-179
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• 1993

Use impacts on environmental deteriorations of trail were studied on the three major trails of Sobaeksan National Park in 1992. The entire width and bare width of trail as the trail condition were significantly greater on the more heavily used trail. Maximum depth of trail was not so great in spite of steeper grade of trail in comparison with the other National Parks. Percentages of deepening. rock-exposed. diverged points as the deterioration types of trail which were surveyed at the total of 105 points were high and trail conditions were significantly different from those of non-deteriorated points. On the Ridge trail. the damaged area more severe than Class 4 reaches about 10,335$m^2$ and the deterioration is accelerated. The dominant trees of the the upper layer in trail edge vegetation are changed from Q. mongolica. Aar mono to Q. mongolica for Huibang trail. and from Pinus densiflora. Q. mongolica to P. densiflora and to Q. mongolica for Biro trail as altitude increases. Rhododendron schlippenbachii. Weigelu subsessilis. Salix hulteni. Rubus crataeglfolius were classified for tolerant species and R. coreanus. Vaccinium koreanum for intolerant species to use impacts. Highly competetive species on the Ridge trail were grouped R. schlippenbachii. W. subsessilis. Rubus crataegifolius and Symplocos chinensis for. pilosa.