• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.255-265
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• 1999

This study deals with forest soil characteristics and their effects on the trafficability of logging vehicles. The study area is the national experimental forest located in Kwangnung. This site has 20m length and is equally divided by 5 surveying ranges with 4m width, on which a tractor(FIATAGRI) attached with logging boogie can drive in 4 driving types, namely 1time-return unload, 1time-return with load of 780-790kg weight of 3 logs, 5 and 10times-return with same load. After one driving type on all surveying ranges, the soil hardness is surveyed 5 times with 3 several type tools, SHM-1 type, lang penetrometer(L-PNTM), and clegg impact soil tester(CIST). A disturbed degree of cover vegetation and sliding conditions of vehicle are also observed. As results, the soil type of the test site was SC by USCS and dry brown forest soil. The cover vegetation is gotten trambled under driving after 3-5 times-return, shrubs leaves are fully fallen and their bark are peeled, and after 10 times-return the cover vegetations were nearly disappeared. The test vehicle has neither slided nor was overthrown. The wheel tracks in the 1-3 ranges, of which unit weight(gd, gt) is high and soil moisture content(MC) is low, were only 1-2cm deep, but those in the 4-5 ranges, of which the gd, gt is low and the MC is high, were 5-7cm deep. In the soil hardness test, which was established in 5 test ranges by types of driving, the more driving times, the higher the hardness. The soil hardness surveyed by L-PNTM has changed slowly and that surveyed by SHM-1 type has risen sharply. In the ranges with higher specific gravity(Gs), higher unit weight, lower MC and higher liquid limit(LL) and plasticity index(PI) was the soil hardness high and the trafficability was good. In the ranges with opposite conditions, also in the ranges of the lower soil hardness, the trafficability must be not good, because the wheel track may be deep. The results from CIST attached with 4kg hammer was not better than expected. So it is recommended to use CIST with 2.5kg or 0.5kg hammer.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.233-240
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• 2017

This experiment was conducted to establish a cultivation system for sorghum in reclaimed soils. Pot experiments were used to test the effects on seedling establishment of sowing depth, soil water content, and soil salinity using seeds of Nampungchal-susu and Hwanggeumchal-susu in reclaimed soil. Field experiments were also conducted to examine differences in growth characteristics and yield production, by sowing time, and planting distance. The result of the pot experiment, examining seedling establishment at various sowing depths revealed that, it was the highest 76.7% when the seeds were sown at a depth of 3 cm. Seedling establishment did not differ with soil water content between 10~30 kpa and at 51~70 kpa. No effects of seed moisture absorption before sowing were observed. Seedling establishment showed no differences with soil salinity below $3.2\;dS\;m^{-1}$, but decreased with Salinity above $4.8\;dS\;m^{-1}$. In field experiments to assess the effects on seedling establishment ratio of sowing time, Nampungchal-susu was revealed to have a high seedling establishment ratio following sowing on June 15. Hwanggeumchal-susu did not exhibits effects of sowing time, on seedling establishment ratio but exhibited higher seedling establishment when in low soil salinity conditions than when sown in high soil salinity conditions. With respect to yield, the yield of the seeds sown on June 15 was higher by 13% for Nampungchal-susu and by 29% for the Hwanggeumchal-susu than that those sown on June 25. With respect to soil salinity, the yield at a soil salinity of $3.2dS\;m^{-1}$ was lower by 23% than that at $1.6dS\;m^{-1}$ or lower for Nampungchal-susu, and was lower by 30% Hwanggeumchal-susu. With respect to planting density, both breeds showed the highest yield at $60{\times}10cm$. These results suggest that a sowing time of June 15 and a seeding distance of $60{\times}10cm$ are appropriate for sorghum in reclaimed land.

• The Korean Journal of Ecology
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• v.27 no.5
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• pp.291-300
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• 2004

This study was carried out to investigate the relationship of occurrence and distribution of Eupatorium rugosum by forest types and soil characteristics in Mt. Namsan in Seoul, Korea. E. rugosum is designated as a harmful non-indigenous plant in ecosystem by the Natural Environment Conservation Act in Korea. E. rugosum grew along roadside and in valleys with some favorable light conditions. E. rugosum occurred in aggregations under Pinus densiflora and Robinia pseudoacacia communities. And it was sparse in forests of Quercus mongolica and P. koraiensis. The representative herb layer species were Oplismenus undulatifolius, and Parthenocissus tricuspidata in the E. rugosum communities. There was a significantly negative correlation between the coverage of E. rugosum and the coverage of tree layer. However, the result of ANOVA of E. rugosum coverage by dominant species of tree layers did not show a significant difference (p>0.05). The level of soil moisture content, organic content, and pH, was slightly higher in communities with E. rugosum than without, but it was statistically non-significant difference. However, it was found that the coverage of E. rugosum was very significantly negative correlated with the depth of top soil profile (litter and fermentation layer, p<0.05).

• Korean Journal of Plant Resources
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• v.33 no.5
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• pp.419-427
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• 2020

Ligusticum chuanxiong Hort. is included in Umbelliferae family, it is one of the Korean traditional medicinal plants as the roots have been used to treat diseases. In this study, the growth characteristics and active compound contents of L. chuanxiong were compared among the different forest sites. As a result, root diameter and root length of L. chuanxiong was the highest in Jeongseon. Also, the fresh weight and dry weight of L. chuanxiong were the highest in Jeongseon. The total content of active compound was 23.27 mg/g the highest in Bonghwa, and 21.59 mg/g in Jeongseon, 15.87 mg/g in Hamyang was accumulated. In this study compares three forest site for cultivating of L. chuanxiong in different climate zone that the best site to product yield were Jeongseon. In this sites were located in higher altitue and lower temperature than other sites, also there were shown that lower soil moisture contents and well-drained soil. It was shown yield and active compound contents of L. chuanxiong was influenced by micro-environment conditions like as altitude, temperature, soil conditions.

• Mycobiology
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• v.31 no.2
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• pp.105-112
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• 2003

Sclerotia of Grifola umbellata were cultivated by two methods such as burying and root inoculation methods. The sclerotia of G. umbellata produced by the burying method were $6.0{\sim}6.8{\times}3.4{\sim}4.6{\times}1.8{\sim}1.9cm$(Width$\times$Length$\times$Thickness) in size and $17.3{\sim}19.6g$ in weight, respectively. Their increase rate was $1.10{\times}1.12$ times. On the other hand, the sclerotia cultivated by the root inoculation method were $18.3{\sim}31.5{\times}12.5{\sim}26.4{\times}3.1{\sim}3.7cm(W{\times}L{\times}T)$ in size and $219.1{\sim}576.6g$ in weight, respectively. Their growth increment was $11.18{\sim}39.77$ times. The rhizomorphs of Armillaria mellea were developed with a high density under fallen leaves layer covering cultivation site, and distributed mainly between soil surface and soil depth of about 10 cm as well as colonized prominently on the inoculated wood logs. Fungal interaction between G. umbellata and A. mellea were observed mainly in the stage of white sclerotium of G. umbellata. The sclerotia of G. umbellata which were developed newly and harvested in the root inoculation method were twined with root hairs of host tree and rhizomorphs of A. mellea. The sclerotia of G. umbellata decomposing root hairs of host tree were confirmed through SEM examination. Physiochemical characteristics of soil in all cultivation sites had no significant differences. Soil pH were in the range of pH $3.98{\sim}4.40$. Organic matters were the range of $17.97{\sim}23.86%$ and moisture contents of soil were $12.00{\sim}18.20%$. Soil temperatures showed $12.9{\sim}13.8^{\circ}C$ in November and $22.0{\sim}23.9^{\circ}C$ in August, respectively. In conclusion, the root inoculation method seems to be a practical method for cultivating sclerotia of G. umbellata due to its many advantages such as simplicity of inoculation process, shortening of cultivation periods and facility of harvest.

• The Journal of Engineering Geology
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• v.21 no.3
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• pp.239-246
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• 2011

Upon encountering weathering soil at a construction site, it may be necessary to change the design and construction plans for geotechnical structures. When weathering soil is exposed to air, the weathering process proceeds rapidly, resulting in significant damage to geotechnical structures, particle defects, and an increase in moisture sensitivity. The management of weathering-soil compaction is challenging. Because the engineering properties of weathering-soils vary regionally, it is important to report the result of research into the regional characteristics of such soils. At two locations of granite gneiss in the Gansung area of Gangwon-do, geological studies were performed at 22 and 8 sites, respectively. At each site, test samples were collected for analysis by XRD and to measure particle size, consistency, and compaction. To evaluate the suitability of the material for road subgrade, we examined the interrelationship between CBR value and the uniformity coefficient, the 200 sieve passing ratio and the aggregate ${\geq}$ 2 mm) content. We found that for the weathered granite soil, aggregate sized > 2 mm has a significant effect on the CBR value. In addition, the mixing of aggregate sized > 2 mm with sub-quality soil improves the soil condition.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.3
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• pp.167-172
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• 1990

Some of soil properties already known were selected for the determination of their effect on soil moisture characteristics. Total number of 2,808 representative samples from all over Korea with the exception of Jeju Island were investigated. 1. Available water contents were 4.7 for S, 7.7 for LS, 13.2 for SL, 17.7 for L, 19.2 for SiL, 15.9 for CL, 14.5 for SCL, 18.7 for SiCL, 17.3 for SiC, and 14.9% for C, respectively. 2. Simple regression analysis showed that field capacity and available water content were most strongly associated with sand content in coarse-textured soils, and with organic matter content in fine-textured soils, whereas permanent wilting point was closely associated with clay content. 3. Available water was strongly associated with silt content and also significantly with field capacity, but either not at all or negatively with permanent wilting point. 4. Prediction equations for available water and field capacity were drown out from known soil properties, which can be used for each textural class.

• Journal of Environmental Science International
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• v.27 no.5
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• pp.291-297
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• 2018

Vertical farming systems offer many advantages in urban spaces. They have also been proposed as an engineering solution to increase the productivity per unit area of cultivated land by extending crop production in the vertical dimension. However, soil water retention is a major constraint affecting the plant environment. This study analyzed the effects of growth environment of Tropaeolum majus and Fragaria spp., on the vertical farming system, by using four different types of cover material types including sphagnum moss (Control), a shading net (S.N.), multi-layered fabric (M.L.F.), and non-woven fabric (N.W.F.). The volumetric soil moisture contents and plant characteristics were investigated from May to September 2014. Plant materials were individually cultivated in hanging baskets measuring $30{\times}17{\times}17cm$, filled with a mixture of soil and perlite, and placed at 1.5m height. Each treatment was performed in quadruplicate and consisted of five plants, amounting to a total of 20 plants. The analysis indicated that different covers were associated with multiple functions and soil water retention improvements may have a positive impact on the vertical farming system. The difference in soil water retention increased in the following order: M.L.F. > Control > N.W.F. > S.N.. Furthermore, the differences in plant height and survival rate increased in the following order: M.L.F. > Control > N.W.F. > S.N. Therefore, M.L.F yielded satisfactory good response for the vertical farming system of cover materials. Our results clearly demonstrate that vertical spaces represent an attractive alternative to urban farming and suggest that further increases in yield may be achieved via different cover materials in vertical farming using hanging baskets.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.725-735
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• 2011

This study was carried out to analyze the vegetation properties, soil characteristics, and ordination of Stewartia koreana community of Mt. Jirisan in Korea. The S. koreana community was classified into S. koreana-Quercus mongolica serrata community, S. koreana-Quercus mongolica community, and Typical community. In specific, S. koreana-Q. serrata community was classified into two subgroups such as Carpinus laxiflora subcommunity and typical subcommunity. The S. koreana community was found out to be located at an elevation of 409m to 1,604m. The Results of importance value on the S. koreana community consisted of the following in order: 75.47% of S. koreana, the highest, 21.83% of Q. serrata, 18.65% of Q. mongolica, 18.19% of Acer pseudosieboldianum, 10.56% of Rhododendron schlippenbachii, 10.36% of Styrax japonicus. In the targeted study sites, soil organic matter, total nitrogen, available phosphate, exchangeable potassium, soil moisture and soil pH were 3.15~39.1%, 0.37~11.7%, 0.9~45.4mg/kg, $0.09{\sim}1.48cmol^+/kg$, 19.28~55.47% and 4.08~5.65, respectively. The results of the correlation between communities and soil conditions of S. koreana community by DCCA ordination method are as follows: S. koreana-Q. serrata community was found in the highest elevation and followed in order S. koreana typical community, S. koreana-Q. serrata typical subcommunity, and C. laxiflora subcommunity.

• Journal of the Korean Geotechnical Society
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• v.39 no.12
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• pp.115-125
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• 2023

In this study, we evaluated the behavior of frozen soil using an electrical resistivity survey method-a nondestructive technique-and examined its characteristics through field experiments. Frozen soil was artificially prepared by injecting fluid to accelerate the freezing process, and naturally frozen soil was selected in a nearby area for comparison. A dynamic cone penetration test (DCPT) was performed to compare the reliability of the electrical resistivity survey, and time-domain reflectometry surveys were performed to assess the moisture content of the ground. Field experiments were conducted in February-when the atmosphere temperature was below freezing-and May-when the temperature was above freezing. This temperature-compensated method was used to determine reliability because the behavior of frozen soil depends on the underlying temperature. In the resistivity survey method, a section of high electrical resistivity was observed under freezing conditions due to the frozen water and converted into porosity. The converted porosity was compared with the porosity inferred from the DCPT, and the results showed that the measured electrical resistivity was valid.