• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.55-64
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• 2000

This study was carried out to analyze the characteristics of pH and electrical conductivity(EC) at each stand and soil depth by the artificial acid rain sprinkling in the upper watershed of Mt. Palgong and furthermore to clarify the relationships between forest soil and water purification function. The results obtained in the experimental sites of Quercus acutissima and Larix leptolepis were summarized as follows ; 1. The average soil pH at each soil layer(0~5cm, 0~10cm, 0~20cm in depth) were 4.8, 4.3 and 4.5 for the Quercus acutissima soil and 5.15, 5.19 and 5.21 for the Larix leptolepis soil. The soil pH of Larix leptolepis stand was higher than that of Quercus acutissima stand. In addition, the deeper soil depth was, the higher soil pH was. 2. The soil solution pH of Larix leptolepis stand was higher than that of Quercus acutissima stand. It was due to the high soil pH of Larix leptolepis stand itself and the difference of humus layer thickness. 3. It took time to show the pH buffer capacity of forest soil after application of artificial acid rain in the forest soil. The pH value of soil solution in each experimental site was maximum at this time and then did not increase pH value any more. 4. Soil solution EC increased slowly with pH 3.0 treatment, but it decreased slowly with pH 5.0 treatment over time. It was assumed that the amount of the leached cation and the ions leading buffer action changed at the stands with ranges of acidity treatment. 5. From the trend of soil solution EC at each soil depth, it seemed that the water buffer capacity of the forest soil increased as the soil depth increased.

• Korean Journal of Environmental Agriculture
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• v.31 no.2
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• pp.137-145
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• 2012

BACKGROUND: Along with the surplus rice production, introduction of upland crop cultivations into newly reclaimed tidal areas has gained public attentions in terms of farming diversification and farmers income increase. However, its impacts on the surroundings have not been well studied yet, especially associated with nutrient balance from reclaimed upland cultivation. The objective of this study was to investigate water and nutrient balance during winter barley cultivation as affected different fertilization methods. METHODS AND RESULTS: TN and TP balance for three different plots treated by livestock compost, chemical fertilizer, and no application were monitored during winter green barley cultivation (2010-2011) at the NICS Kyehwa experimental field in Jeonbuk, Korea. Nutrient content in soil and pore water near soil surface appeared to increase, while sub-soil layer remained similar with no fertilization plot. Livestock compost application appeared to increase organic matter content in surface soil compared to chemical fertilization. Crop yield was the greatest with livestock compost application (10.6 t/ha) followed by chemical fertilization (6.9 t/ha) and no application (1.8 t/ha). The nitrogen uptake rate was also greater with livestock compost (52.4%) than chemical fertilizer (48.1%). Phosphorus uptake rate was much smaller (about 7.0%) compared to nitrogen. Nutrient loss by surface and subsurface runoff seemed to be minimal primarily due to small rainfall amount during the winter season. Most of the remaining nutrients, particularly phosphate seemed to be stored in soil layer. Phosphate accumulation appeared to be more phenomenal in the plot applied by livestock compost with higher phosphorus content. CONCLUSION: This study demonstrated that livestock compost application to tidal upland may increase barley crop production and also improve soil fertility by supplying organic content. However, excessive phosphorus supply with livestock compost seems likely to cause a phosphate accumulation problem, unless the nitrogen-based fertilization practice is adjusted.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.994-1001
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• 2008

Freundlich isothermal adsorption parameters, applicable to such biofilter-model as process-lumping model(Lim's model), for sterilized granular activated carbon(GAC), sterilized compost and sterilized equal volume mixture of GAC and compost were obtained and were compared each other, assuming that adsorbents are enclosed by water layer, in order to construct robust process-lumping biofilter model effective for wide-range of hydrophilic volatile organic compounds(VOC). In this investigation 0.04, 0.08, 0.12, 0.16, 0.2, 0.4, 0.8 and 1.0ml of ethanol were added to three kinds of adsorbent-media and were placed at $30^{\circ}{\cdots}$ under the wet condition of the media, which was the same as biofilter operating condition, until the adsorption reached the condition of equilibrium before each adsorbed amount of ethanol was obtained. Then adsorption capacity parameters(K) and adsorption exponents of Freundlich adsorption isotherm equation, which simulates the adsorbed amount of ethanol equilibrated with the ethanol concentration of the condensed water in the pore of the media, were constructed for sterilized granular activated carbon(GAC), sterilized compost and sterilized equal volume mixture of GAC and compost as (0.7566 and $5.070{\times}10^{-7}mg-ethanol/mgmedia/(mg-ethanol/m^3)^{0.7566}$), (0.8827 and $1.000{\times}10^{-8}mg-ethanol/mgmedia/(mg-ethanol/m^3)^{0.8827}$) and (0.5688 and $5.243{\times}10^{-6}mg-ethanol/mgmedia/(mg-ethanol/m^3)^{0.5688}$), respectively. These Freundlich isothermal adsorption parameters were applicable to the adsorption characteristics of biofilter media enclosed with bio-layer. The order of magnitude of the ratio of ethanol-air/water partition coefficient and toluene-air/water partition coefficient was almost consistent to that of ethanol-adsorbed amounts in this experiment with compost and in the investigation of Delhomenie et al. on toluene-adsorption to wet compost.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.39-50
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• 2014

This paper reviews the results of recent observations in the Yeonsuri valley of Mt. Youngmun during springtime (March to May) in 2012. Automated weather stations were installed at twelve sites in the valley to measure temperature and 2, 3 dimensional wind. We examined temporal and spatial characteristics of temperatures and wind data. The Yeonsuri valley springtime average temperature lapse rate between the top and bottom of the entire period is $-0.44^{\circ}C/100$ m. It can be changed by the synoptic weather conditions, the lapse rates is greatest in order of clear days ($-0.48^{\circ}C/100$ m), rainy ($-0.41^{\circ}C/100$ m) and cloudy days ($-0.40^{\circ}C/100$ m). In the night, the temperature inversion layer (thermal belt) and the cold pool are formed within the valley. In addition, we measured temperature and wind distribution from the bottom to 3.5 m, the cold layers existed up to 1.5 m, which were affected by ground mixed layer. The results will provide useful guidance on agricultural practices as well as model simulations.

• Korean Journal of Poultry Science
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• v.17 no.3
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• pp.167-177
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• 1990

In order to investigate an effect of the feed restriction on the laying performance, 208 White Leghorn strain layer of 36 week-old were divided to 4 groups of 52 birds each and raised for 1 week of previous feeding and for the subsequent 3 weeks of experimental restricted feeding. The egg production, daily egg mass and feed efficiency of four groups of birds fed daily 100g, 95g, 90f and 85g of a commercial diet, respectively, which were compared with those of the original 2879 birds fed l13g of diet per day as control. During 3 weeks of experimental restricted feeding, period, daily body weight nam was decreased linearly as the degree of restriction increased in birds fed 100, 95, 90 and 85g of diet. Hen day egg production, egg weight and daily egg mass was linearly related to the diet intake level. then feed intake(x, g day$^{-1}$ ) showed a positive regression equations with the henday egg production(y, % ), egg weight(y, g egg$^{-1}$ ) and egg mass(y, g bird$^{-1}$ ) as y＝38.75＋0.3753$\times$(r＝0.503, n＝15), y＝48.2＋0.08868$\times$(r＝0.835, n＝ 15) and y＝15.69＋0.2786$\times$(r＝0.597, n＝15), respectively. Feed efficiency was increased to a plateau in birds fed 95g of diet. The estimated energy utilization for egg production was reached to a plateau in birds fed 95g of diet and the highst protein utilization was shown in birds fed 90g of diet anions birds fed graded levels of diet. And the feed restriction did not affect on the egg shell contents, while protein contents of egg were shown a trend to be increased and lipids and cholesterol contents of eggs was decreased according to the diet intake lowered. The results suggested that the improved feed efficiencies of birds restricted under 16% of diet(above 95g of diet) will be due to increased energy and protein utilization for egg production and feed restriction above 16% will be aboided. In the range from 113g to 95g of diet feeding, the crude profit was increased as the feed restricted in the case of egg price 600 won kg$^{-1}$ and feed price 200 won kg$^{-1}$ .

• Journal of Wetlands Research
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• v.17 no.2
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• pp.124-129
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• 2015

In order to get as ecological basic data for river restoration, vegetation investigation was conducted in natural river and analysed it synecological methods, such as ordination cluster. 29 plant communities units were identified and the major dominant plant communites were Quercus mongolica community, Pinus densiflora community, Populus davidiana community, Q. variabilis community and Prunus sargentii community. River vegetations were classified into ravine and gorge forest type and riverine softwood forest type. Ravine and gorge forest was dominanted by hardwood which located in steep slope and in high elevation, and riverine softwood forest by softwood, salix spp. Naturality was an important criterion for the selection of rivers, so many of the selected rivers are located in the upper stream and mid stream rather than the lower stream, where more human intervention is involved. Plant communities were consisted of hardwood forest(44 plots, 92%) and softwood forest(4 plot, 8%), respectively. PCA with total layer data showed 5 groups of communities: Q. mongolica community group, Prunus sargentii community group, Pinus densiflora community group, Prunus sargentii community - Pinus densiflora community group and the rest communities group. PCA with tree layer showed 3 groups: Q. mongolica community group, Prunus sargentii community group, and the rest community group. Cluster analysis also a showed a similar communities group to PCA ordination, but Magnolia sieboldii community and Prunus sargentii community were distinguished from the PCA result. From the result, it can be concluded that the plant communities of riparian be divided into hardwood and softwood forest by statistical techniques. It was appropriate to plant species such as Quercus mongolica, Pinus densiflora, Populus davidiana, Quercus variabilis and Prunus sargentii, at levee zone and high water level. And Sliax spp. were appropriate for planted plants at waterfront and low water level. The herb species to be planted on the floodplain were recommanded in the species composition co-occurred with the woody species.

• Journal of Veterinary Clinics
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• v.28 no.5
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• pp.486-496
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• 2011

A special mesenchymal tissue layer called perichondrium has a chondrogenic capacity and is a candidate tissue for engineering of cartilage. To overcome limited potential for chondrocyte proliferation and re-absorption, we studied a method of cartilage tissue engineering comprising chondrocyte-hydrogel pluronic complex (CPC) and cultured perichondrial cell sheet (cPCs) which entirely cover CPC. For effective cartilage regeneration, cell-sheet engineering technique of high-density culture was used for fabrication of cPCs. Hydrogel pluronic as a biomimetic cell carrier used for stable and maintains the chondrocytes. The human cPCs was cultured as a single layer and entirely covered CPC. The tissue engineered constructs were implanted into the dorsal subcutaneous tissue pocket on nude mice (n = 6). CPC without cPCs were used as a controls (N = 6). Engineered cartilage specimens were harvested at 12 weeks after implantation and evaluated with gross morphology and histological examination. Biological analysis was also performed for glycosaminoglycan (GAG) and type II collagen. Indeed, we performed additional in vivo studies of cartilage regeneration using canine large fullthickness chondrial defect model. The dogs were allocated to the experimental groups as treated chondrocyte sheets with perichondrial cell sheet group (n = 4), and chondrocyte sheets only group (n = 4). The histological and biochemical studies performed 12 weeks later as same manners as nude mouse but additional immunofluorescence study. Grossly, the size of cartilage specimen of cPCs covered group was larger than that of the control. On histological examination, the specimen of cPCs covered group showed typical characteristics of cartilage tissue. The contents of GAG and type II collagen were higher in cPCs covered group than that of the control. These studies demonstrated the potential of such CPC/cPCs constructs to support chondrogenesis in vivo. In conclusion, the method of cartilage tissue engineering using cPCs supposed to be an effective method with higher cartilage tissue gain. We suggest a new method of cartilage tissue engineering using cultured perichondrial cell sheet as a promising strategy for cartilage tissue reconstruction.

• Parasites, Hosts and Diseases
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• v.29 no.3
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• pp.245-258
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• 1991

In order to determine the antigenic localization in the tissues of the adult Metagonimus yokegawai, immunogoldlabeling method was applied using serum immunoglobulins (IgG) of cats which were infected with isolated metacercariae from Plecoglossus altivelis. The sectioned worm tissue was embedded in Lowicryl HM 20 medium and stained with infected serum IgG and protein A gold complex (particle size: 12 nm) , It was observed by electron microscopy at each tissue of the worm. The gold particles were observed on the tegumental syncytium as well as cytoplasm of tegumental cells and epithelial lamella of the caecum. The gold particles were not observed on the basal lamina of the tegument, interstitial matrix of the parenchyma, the muscle tissue and mitochondria of the tegument. The gold particles were specifically labeled in the secretory granules in the vitelline cells. They were also labeled on the lumen of bladder and egg shell. The above findings showed that antigenic materials in the tissue of adult worms were specifically concentrated on the tegumental syncytium as well as cytoplasm of tegumental cells and epithelial lamella of the caecum.

• Journal of the Korean Geotechnical Society
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• v.34 no.2
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• pp.19-32
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• 2018

During the process of gas hydrate extraction in the deep seabed, fine diatom particle migration occurs, which causes the seabed slope failure and the productivity deterioration of the gas hydrate. Therefore, a study related with the changes of the ground characteristics due to the fine particle migration is required. The objective of this study is to investigate the change of hydraulic properties of sand due to the migration of fine diatom particle in sandy soils. In order to simulate the sediments of the Ulleung basin gas hydrate in the East Sea, fifteen sand-diatom mixtures that have different diatom volume fractions (DVF) are prepared. During the falling head permeability tests, the coefficients of permeability are measured according to the DVF. In addition, for the simulation of the fine diatom particle migration, constant head permeability tests are conducted by applying the hydraulic pressures of 3 kPa, 6kPa, and 9 kPa on a specimen composed of two layers: a specimen with 50% DVF in upper layer and a specimen with 0% DVF in lower layer. Furthermore, the coefficient of permeability and the electrical resistivity of the migration zone are measured during the constant head permeability test. The falling head permeability tests show that the coefficient of permeability decreases as the DVF of the specimen increases. In addition, the gradient of the coefficient of permeability curve decreases in the DVF range of 10%~50% compared with that of 0%~10%, and increases above 50% in DVF. The result of constant head permeability tests shows that the coefficient of permeability decreases and electrical resistivity increases in the migration zone due to the fine diatom particle migration. This study demonstrates that fine diatom particle migration reduces the permeability of the soils and the behavior of the migration zone due to the fine diatom particle migration may be estimated based on the reversal relationship between the coefficient of permeability and the electrical resistivity.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.211-230
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• 2016

Detailed mapping along the Keumwang fault reveals a complex history of multiple brittle reactivations following late Jurassic and early Cretaceous ductile shearing. The fault core consists of a 10~50 m thick fault gouge layer bounded by a 30~100 m thick damaged zone. The Pre-cambrian gneiss and Jurassic granite underwent at least six distinct stages of fault movements based on deformation environment, time and mechanism. Each stage characterized by fault kinematics and dynamics at different deformation environment. Stage 1 generated mylonite series along the Keumwang shear zone by sinistral ductile shearing during late Jurassic and early Cretaceous. Stage 2 was a mostly brittle event generating cataclasite series superimposed on the mylonite series of the Keumwang shear zone. The roundness of pophyroclastes and the amount of matrix increase from host rocks to ultracataclasite indicating stronger cataclastic flow toward the fault core. At stage 3, fault gouge layer superimposed on the cataclasite generated during stage 2 and the sedimentary basins (Umsung and Pungam) formed along the fault by sinistral strike-slip movement. Fragments of older cataclasite suspended in the fault gouge suggest extensive reworking of fault rocks at brittle deformation environments. At stage 4, systematic en-echelon folds, joints and faults were formed in the sedimentary basins by sinistral strike-slip reactivation of the Keumwang fault. Most of the shearing is accommodated by slip along foliations and on discrete shear surfaces, while shear deformation tends to be relatively uniformly distributed within the fault damage zone developed in the mudrocks in the sedimentary basins. Fine-grained andesitic rocks intruded during stage 4. Stage 5 dextral strike-slip activity produced shear planes and bands in the andesitic rocks. ESR(Electron Spin Resonance) dates of fault gouge show temporal clustering within active period and migrating along the strike of the Keumwang fault during the stage 6 at the Quaternary period.