• Korean Journal of Organic Agriculture
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• 제21권4호
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• pp.753-767
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• 2013

Soil contamination has continuously increased worldwide, thus the remediation for the contaminated soils has risen steadily. However, the consideration of ecological safety for the remediated soils and their agricultural uses has been very limited. Therefore, this study was to investigate the influences of selected environmentally-friendly agricultural materials, organic by-product fertilizer (OF), charcoal (CC), and biochar (BC), as soil conditioners for improving poor chemical properties of fuel-oil removed soil by land farming technique. Two different remediated soils, remediated soil A (RSA) and remediated soil B (RSB), were selected. Soil texture of both RSA and RSB was sandy loam. The chemical properties of RSA and RSB were as follows: soil pHs of 8.5 and 8.7, soil organic matter contents of 7.4 and 5.5g $kg^{-1}$, total nitrogen contents of 0.26 and 0.10g $kg^{-1}$, available phosphorus concentrations of 7.2 and 4.4mg $kg^{-1}$, and exchangeable calcium concentrations of 14.8 and $11.7cmol_c$ $kg^{-1}$, respectively. Results of the properties were not reached for the optimal values for cultivating crops that were recommended by National Academy of Agricultural Science at Rural Development Administration in Korea. However, after applying OF, CC, and BC, the chemical properties of soils were selectively improved, which were that soil organic matter content and available phosphorus concentration increased, whereas the soil pH were not changed. In particular, the chemical properties were positively changed more with the application of 5.0% biochar. Thus, continuous management of the remediated soils with applying the eco-friendly agricultural materials can improve the quality of reme-diated soils.

• Korean Journal of Environment and Ecology
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• 제30권6호
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• pp.929-938
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• 2016

This study reviewed the external morphological characteristics of a rare species, Exochorda serratifolia S.Moore, in South Korea through a comparison of its previous records. Also, a distribution map of this species was made using previous data on flora and voucher specimens. Furthermore, the soil characteristics of Exochorda serratifolia S.Moore was analysed in order to determine the correlation between external morphological features and soil characteristics. At the study sites, soil organic matter, total nitrogen, available phosphates, exchangeable potassium, exchangeable calcium, exchangeable magnesium, cation exchange capacity and soil pH were found to be in the ranges of 3.25-29.83%, 0.15-1.14%, 3.0-156 mg/kg, $0.39-1.49cmol^+/kg$, $2.48-38.07cmol^+/kg$, $0.77-18.29cmol^+/kg$, $7.3-23.0cmol^+/kg$ and 4.6-7.1 respectively. The soil condition surrounding the population of Exochorda serratifolia S.Moore in Mt. Ap-san (Daegu) was found to have higher percentages of organic matter, total nitrogen, and cation exchange capacity than the soil condition of other populations. Moreover, the length of inflorescence and the number of flowers in this population were significantly higher than the populations studied in other areas (P < 0.001). We also identified a significant correlation between genetic, geographic distance and several morphological characteristics. A comprehensive review of various data on Exochorda serratifolia S.Moore such as external morphological characteristics, genetic structure, growth conditions, vegetation properties, and environmental characteristics is required to understand its growth characteristics and conserve this rare species.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제8권1호
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• pp.13-24
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• 1988

This paper is concentrated on the development of oxygen transfer system by U-tube deep shaft in biological fluidised bed process. The depth of the shaft is 32 m, it is composed of downcomer and riser. Not only flow pattern and oxygen transfer in the deep shaft but also oxygen limitation in biofilm and oxygen utilization in biological fluidised bed are investigated. In this investigation, driving force for liquid circulation in the deep shaft is affected by air injection depth and gas hold-up in downcomer. Flow pattern of the deep shaft is revealed to plug flow. When flow velocity in the deep shaft is maintained to 0.52 m/sec, $K_La$ value is peak at 25~30 m depth in riser. The efficiency of dissolved oxygen supply which passed from the deep shaft to biological fluidised bed is estimated to 56~81 % in the organic wastewater treatment using the deep shaft and when dissolved oxygen concentration is 9.2 mg/l and over, limiting factors of flux and substrate within biofilm are organic materials. Terefore, organic loadings could be increase without decreasing of BOD removal efficiency.

• Korean Journal of Soil Science and Fertilizer
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• 제35권2호
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• pp.77-86
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• 2002

Soil color characteristics were measured by a optical instrument, colorimeter, comparing with the conventional Munsell color chart and related to the chemical properties of soils. Total of the 67 experimental soils were taken from tobacco fields that located at Cheongwon, Enmseong, Boeun, Goesan, Jincheon, and Chungju countries in Chungbuk Province having the 29 soil series including Samgag. The values of L, a, and b measured by colorimeter were closely related with hue, value, and chroma of Munsell color chart, respectively, indicating the quantitative measurement of soil color characteristics. The standard deviations in measurement for L, a, and b values was smaller in soil sample passed by 0.5 mm sieve than 2 mm sieve, suggesting that soil particle size less than 0.5 mm was better condition for colorimeter measurement. The values of L and b measured by colorimeter showed a tendency to decrease as increase of soil moisture content but nearly on difference with moisture condition for the value of a. However, correlation coefficient between air dry samples and wet soil samples(soil moisture retension of -10 hPa) for measurements of L, a and b value were more than 0.9 showing the same tendency in measurement. Consequently, air dry soil passed by 0.5 mm sieve was recommended to desirable conditions for stable measurement by colorimeter. The measured values by colorimeter were significantly correlated with organic matter, CEC, exchangeable Ca and Mg, showing the highest correlation coefficient between L value and organic matter.

• Korean Journal of Environment and Ecology
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• 제24권5호
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• pp.566-574
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• 2010

This study was carried out for the purpose of understanding the situation of the urban forest and presenting basic data bases for a proper management plan through the analysis of forest vegetation and soil characteristics. In three representative urban forests of Deajeon, we analyzed the differences of vegetation and soil properties in each geological location. The indices of ecological health such as Species Diversity and Maximum Species Diversity are increasing in the order of Namseon Park, Wolpyung Park and Mt. Bomun; the first is in the center of the city, the second is well-conserved inner-city park and the third is in the border of the city. In the soil analysis of Namseon Park where human disturbance is strong, the surface fuel bed was very thin just 0.5cm and the soil was harder than the other two urban forests, the soil hardness was $0.5{\sim}3.7kg/cm^2$. All three urban forests showed low $pH_{1:5}$ under 5.0 except Robinia pseudo-acasia association of Wolpyung and low exchangeable cation level. These results say that the urban forests of Deajeon have been being acidified severely and the eluviation of exchangeable cation is proceeding. The organic matter and the available phosphate level was lower than the average level of Korean forest. It means that nutrition supply is not sufficient. In Daejeon urban forests, the management plan of urban forest is necessary according to the analysis result of vegetation and soil.

• Journal of Animal Science and Technology
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• 제54권5호
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• pp.349-354
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• 2012

In this experiment, two inclusion levels (15 and 30% of diets, as-fed basis) of brown rice (BR) were tested against a control diet with 0% BR (51% wheat flour of diet). Six female Miniature Poodles (8~9 months age, initial mean body weight of 3.5 kg) were assigned to treatments in replicated $3{\times}3$ Latin square design. Total tract digestibilities of DM, OM, CP, acid hydrolyzed fat and gross energy increased linearly (P<0.05), and observed digestible energy and metabolizable energy values also increased linearly (P<0.001 and P=0.007, respectively) with increasing BR inclusion levels. Wet and dry fecal output decreased linearly (P=0.001) with increasing BR inclusion levels in the diets. Linear (P<0.05) effects was observed in fecal score for dogs fed BR and fecal ammonia concentration increased linearly (P<0.05) in response to increasing BR inclusion level. It seems that the increase in fecal ammonia concentration may be partially related to the decrease in short-chain fatty acid concentration (P<0.01). This study clearly demonstrates that BR improves nutrients digestibility and fecal characteristics of dog.

• The Korean Journal of Ecology
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• 제25권3호
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• pp.145-152
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• 2002

Saussurea chabyoungsanica was recorded in new species by Lim Hyoung Tak in 1997. In order to understand the entity of new species, we investigated the new distribution sites, vegetation structure and soil environmental factors. Additionally discovered distribution sites of S. chabyoungsanica were Manduckbong, Mt. Sukbyoung, Mt. Duckhang, and Sukgaejae, which were located on ridge of the Taebaek Mountains. Those sites are typical limestone zones of Korea and among them Sukgaejae belongs to lower great limestone area and Manduckbong, Mt. Sukbyoung and Mt. Duckhang belong to upper great limestone area. According to the result of phytosociological study, plant communities of S. chabyoungsanica were classified by 1 Community group, 4 Communities and 2 Subcommunities; Carex humilis var. nana-Saussurea chabyoungsanica Community group in wide sense Quercus mongolica Community group, Lespedeza maximowiczii-Saussurea chabyounsanica Community, Galium kinuta-Saussurea chabyoungsanica Community, Salvia chanryonica-Saussurea chabyoungsanica Community, Zabelia coreana-Saussurea chabyoungsanica Community. Environmental factor analysis of habitat showed that the distribution site of S. chabyoungsanica was ridge of North aspect and displayed pH $7{\sim}8$ typical of limestone. Soil moisture content was high, whereas organic matter content was low. Considering its high occurrence in sites of $1{\sim}10cm$ in soil depth, and of $30{\sim}45%$ in relative light intensity, major distribution sites were outcrops and boundaries between shrubland and forest. After community division by vegetation structure in habitat of S. chabyoungsanica, we investigated characters of soil environment by community. As a result of PCA analysis of soil sample by community, it was possible to divide community by characters of soil environmental factor. The cumulative value of contribution rate represented in second dimension space was 73% and the major factors for that value were soil texture, organic matter content and field capacity.

• Journal of the Korean Society of Marine Environment & Safety
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• 제22권1호
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• pp.1-10
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• 2016

In this paper, an analysis of the inflowing pollution load of the rivers in Hampyeong bay showed the average organic matter pollution loads of BOD, COD, and TOC to be 79.7 kg-BOD/day, 144.06 kg-COD/day, and 93.0 kg-TOC/day, respectively. The inflowing organic matter pollution load was the heaviest in Sonbul dike, followed by Jupo bridge and Yangman complex. With regard to season, the load characteristics were outstanding in July, the rainy period in the summer. The average inflowing pollution loads of nutrients were 20.9 kg-DIN/day, 17.1 kg-DIP/day, 148 kg-TN/day, and 37.4 kg-TP/day A comparison of the inflowing nutrients loads for each river showed the load to be the heaviest in Yangman complex, followed by Baegok bridge and Jupo bridge. In the experiment on the material budgets of Hampyeong bridge conducted using a box model, the detention time of fresh water was found to be 52.4 days, with the bay displaying the characteristics of a so dissolved inorganic nitrogen (DIN) in the nutrients material budgets, ${\Delta}DIN$ values were found to be negative, indicating the tendency of consumption and open sea leak by photosynthesis to be higher than the nitrogen that flowed in. As for dissolved inorganic phosphorus (DIP), ${\Delta}DIP$ showed positive values, indicating a tendency for accumulation as the supply through organic matter decomposition, elution load of sediments, and inflowing load of the river turned out to be higher than the consumption by phytoplankton and outflow to open sea.

• The Korean Journal of Ecology
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• 제25권2호
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• pp.75-82
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• 2002

Saussurea chabyoungsanica was recorded in new species by Lim Hyoung Tak in 1997. In order to understand the entity of new species, we investigated the new distribution sites, vegetation structure and soil environmental factors. Additionally discovered distribution sites of S. chabyoungsanica were Manduckbong, Mt. Sukbyoung, Mt. Duckhang, and Sukgaejae, which were located on ridge of the Taebaek mountains. Those sites are typical limestone zones of Korea and among them Sukgaejae belongs to lower great limestone area and Manduckbong, Mt. Sukbyoung and Mt. Duckhang belong to uper great limestone area. According to the result of phytosociological study, plant communities of S. chabyoungsanica were classified by 1 Community group, 4 Communities and 2 Subcommunities; Carex humilis var. nana - Saussurea chabyoungsanica Community group in wide sense Quercus mongolica Community group, Lespedeza maximowiczii- Saussurea chabyoungsanica Community, Galium kinuta - Saussurea chabyongsanica Community, Saliva chanryonica - Saussurea chabyoungsanica Community, Zabelia coreana - Saussurea chabyoungsanica Community. Environmental factor analysis of habitat showed that the distribution site of S. chabyoungsanica was ridge of North aspect and displayed pH 7∼8 typical of limestone. Soil moisture content was high, whereas organic matter content was low. Considering its high occurrence in sites of 1∼10cm in soil depth, and of 30∼45% in relative light intensity, major distribution sites were outcrops and boundaries between shrubland and forest. After community division by vegetation structure in habitat of S. chabyoungsanica, we investigated characters of soil environment by community. As a result of PCA analysis of soil sample by community, it was possible to divide community by characters of soil environmental factor. The cumulative value of contribution rate represented in second dimension space was 73% and the major factors for that value were soil texture, organic matter content and field capacity.

• Journal of the Korean Institute of Gas
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• 제15권4호
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• pp.7-14
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• 2011

Using 20 L spherical explosion vessel and differential scanning calorimeter (DSC), an experimental investigation was carried on explosion characteristics and thermal decomposition of some reactive organic dust. As the result, the minimum explosion concentration of Benzoyl peroxide (BPO), Phthalic anhydride (PA) and 1-Hydroxybenzotriazol (HBT) exist between 10 and 15 g/$m^3$, which indicates that their explosion sensitivity are high. The maximum Kst values of HBT, PA and 97 % BPO are 251, 146 and 80 [$bar{\cdot}m/s$], respectively and the explosion severity of HBT is the explosion class of St-2. The flame velocity was also calculated from the combustion time of dust and flame arrival time to estimate the flame propagation characteristics in a closed vessel. The decomposition temperature and heat of decomposition reaction for 97 % BPO and HBT are $107^{\circ}C$ (1025 J/g), $214^{\circ}C$ (1666 J/g), respectively and it was found that these low decomposition temperature and high released heat affect the explosion characteristics.