• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1049-1057
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• 2012

The study investigated the biochemical methane potential (BMP) assay of pig slurry supplemented with mixed methanogens and cellulolytic bacteria to improve anaerobic digestion for methane production. For the BMP assay, 7 different microbial supplementation groups consisted of the cultures of mixed methanogens (M), Fibrobacter succinogenes (FS), Ruminococcus flavefaciensn (RF), R. albus (RA), RA+FS, M+RA+FS, and control. The cultures were added in the batch reactors with the increasing dose levels of 1% (0.5 mL), 3% (1.5 mL) and 5% (2.5 mL). Incubation for the BMP assay was carried out for 60 days at $38^{\circ}C$ using anaerobic digestate obtained from an anaerobic digester with pig slurry as inoculum. In results, 5% RF and RA+FS increased total biogas up to 8.1 and 8.4%, respectively, compared with that of control (p<0.05). All 5% microbial culture supplements significantly increased methane production up to 12.1~17.9% compared with that of control (p<0.05). Total solid (TS) and volatile solid (VS) digestion efficiencies showed no relationship to the increased supplementation levels of microbial cultures. After incubation, pH values in all treatment groups ranged between 7.527 and 7.657 indicating that methanogensis was not inhibited during the incubation. In conclusion, the results indicated that both hydrolysis and methanogenesis stages for methane production in anaerobic batch reactors were influenced by the supplemented microorganisms due to the chemical characteristics of pig slurry, but only the 5% supplementation level of all microbial culture supplements used in the experiment affected methane production.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.354-364
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• 2020

This study was conducted to examine the potential of inducing salinity stress on cylindrical paper pot tomato seedlings to inhibit overgrowth. Potassium fertilizers, sulfate of potash (K₂SO₄), muriate of potash (KCl), and monopotassium phosphate (KH₂PO₄), were prepared as two solutions of (5 and 10) dS·m^-1 salinity level, respectively, to investigate the influence on tomato (Lycopersicon esculentum Mill.) seedling growth. We also investigated the adaptability and survivability of treated tomato seedlings with high-salinity potassium (10 dS·m^-1 KCl) to harsh environmental conditions (water deficit, low temperature, and storage conditions). Repeated addition of high-salinity level KCl, K₂SO₄, or KH₂PO₄ markedly decreased the dry matter of shoot and root, leaf area, and net assimilate rates (NAR) but increased the stem diameter of seedlings. Among the three sources, the relative growth rate of plant height (RGR_H) was most sensitive to KCl addition; increasing salinity levels of KCl solution decreased the RGR_H of seedlings. The compactness, which directly reflects the stocky growth index, increased in KCl or KH₂PO₄ treatments. After a week's water deficit, severely wilted seedlings were observed in control seedlings (untreated with KCl), but no wilted seedlings were observed in the KCl treated seedlings, and the relative water content (RWC) of the untreated seedlings significantly decreased by 23 %, while that of the pretreated seedlings only decreased by 8 %. The increase in ion leakage of KCl treated seedlings at low temperatures was less than that of untreated seedlings. Furthermore, there was far lower damage proportion on pretreated seedlings at (9, 12, and 15)℃ storage temperatures after 20 days, compared with on unpretreated seedlings. Our results suggest that high-salinity potassium fertilizer, especially KCl, is effective in preventing tomato seedling overgrowth, while it also improves tolerance.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.115-122
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• 2017

Objective of this research was to investigate the influence of lowered substrate pH on the reduction of bicarbonate injury in the vegetative growth of 'Ssanta' strawberry. The acid substrate was formulated by mixing sphagnum peat moss with pine bark (5:5, v/v) and the pH, EC, and CEC of the substrate were 4.07, $0.46dS{\cdot}m^{-1}$, and $91.3cmol^+{\cdot}kg^{-1}$, respectively. To adjust the pH of acid substrate, various amount of dolomitic lime [$CaMg(CO_3)_2$] were incorporated with the rate of 0 (untreated), 1, 2, 3, and $4g{\cdot}L^{-1}$. Then, mother plants were transplanted and grown with fertilizer solution containing $240mg{\cdot}L^{-1}$ of the $HCO_3{^-}$ and equal concentrations of essential nutrients to Hoagland solution. In growth of 'Ssanta' strawberry, fresh weight of mother plants were the highest in the treatment of $2g{\cdot}L^{-1}$ dolomitic lime such as 102.1 g followed by 94.7 g in $1g{\cdot}L^{-1}$, 91.2 g in $3g{\cdot}L^{-1}$, 75.7 g in $0g{\cdot}L^{-1}$ and 72.3 g in $4g{\cdot}L^{-1}$ treatments. The dry weight showed a similar tendency to fresh weight. At 140 days after transplanting, 5.8, 9.8, 11.8, 8.8, and 5.0 daughter plants were derived from each of the mother plants in the treatments of 0, 1, 2, 3, and $4g{\cdot}L^{-1}$ dolomitic lime, respectively. The highest occurrence of daughter plants were observed in the treatments $2g{\cdot}L^{-1}$ dolomitic lime. The substrate pH and bicarbonate concentration of 'Ssanta' strawberry seedlings in the 1 and $2g{\cdot}L^{-1}$ dolomitic lime treatments were maintained at a proper range such as 5.6 to 6.2. The micro-nutrient contents of above ground tissue in mother plants were the highest in $2g{\cdot}L^{-1}$ and the lowest in $4g{\cdot}L^{-1}$ dolomitic lime treatment. The above results indicate that incorporation rate of dolomitic lime in acid substrate with the pH of around 4 is $2g{\cdot}L^{-1}$ to raise the 'Ssanta' strawberry in propagation.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.51-56
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• 2015

The objective of this study was to evaluate the effect of silicate fertilizer on growth, physiology and abiotic stress tolerance of Chinese cabbage seedlings. Five silicate concentrations (8, 16, 32, 64, and 128mM) and control (non-treatment) were applied to Chinese cabbage seedlings twice a week. Three weeks after application of silicate treatment, seedlings were used for treating abiotic stresses and were assessed for growth and physiological characteristics. Growth parameters significantly increased in 8, 16, and 32mM treatments except 64 and 128mM. Total root surface area, total root length, and number of root tips increased in 8, 16 and 32mM treatments, but they decreased in treated seedlings with 64 and 128mM of silicate. The highest growth parameters and root morphology were observed in 8mM treatment. As for the effect on the seedling physiology, transpiration rates decreased while stomatal diffusive resistance increased to increasing silicate concentration. The application of silicate reduced the electrical conductivity, heating and chilling injury index at high and low temperatures. Silicate enhanced drought tolerance of Chinese seedlings by delaying the starting time of wilting point. The starting time of wilting point in the control was 3 days after discontinuation of irrigation, while in the 8, 64 and 128mM of silicate treatments were 4 days, and the 16 and 32mM treatments were 5 days. All plants were wilted after 5 days in control without irrigation whereas it showed in 8mM treatment after 6 days, in 16, 32, 64, 128mM treatments after 7 days.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.425-433
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• 2011

In order to obtain optimum pre-treatment methods and improve T-N and T-P removal efficiencies, removal rates of pollutants in small-scale livestock wastewater treatment apparatus with water plant filtration bed or activated sludge tank were investigated. Based on the results from the optimum pre-treatment in small-scale livestock wastewater treatment apparatus, removal efficiencies of pollutants in livestock wastewater treatment plant with water plant filtration and activated sludge beds. The removal rates of COD, SS, T-N, and T-P in effluent were 83, 89, 63 and 87% in small-scale livestock wastewater treatment apparatus with water plant filtration bed, respectively. The removal rates of COD, SS, T-N, and T-P in effluent were 96, 95, 86 and 92% in small-scale livestock wastewater treatment apparatus with activated sludge tank, respectively. For increasing the COD, SS, T-N, and T-P removals in small-scale livestock wastewater treatment apparatus, the water plant filtration and activated sludge beds are recommended. In livestock wastewater treatment plant with water plant filtration ($1^{st}$ treatment) and activated sludge ($2^{nd}$ treatment) beds, the concentrations of COD, SS, T-N, and T-P in effluent were 39, 15, 42 and $1mg\;L^{-1}$, respectively. It was shown that the concentrations of COD, SS, T-N, and T-P met acceptable effluent quality standard for livestock wastewater. Based on the above results, the removal rates of COD, SS, T-N, and T-P in effluent were over 99.8, 99.9, 99.2, and 99.9% in livestock wastewater treatment plant, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.937-943
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• 2011

In order to develop constructed wetlands for treating hydroponic wastewater in greenhouses, removal efficiencies and decomposition velocities of pollutants in constructed wetland were investigated for treating hydroponic wastewater. Removal rates of BOD, COD, SS, T-N and T-P in effluent in constructed wetlands were 88%, 79%, 92%, 64% and 92%, respectively. The decomposition velocities (K; $day^{-1}$) of pollutants in $1^{st}$ HF bed of constructed wetlands were higher in the order of SS ($0.54day^{-1}$) > BOD ($0.39day^{-1}$) > COD ($0.27day^{-1}$) > T-P ($0.26day^{-1}$) > T-N ($0.06day^{-1}$). In $1^{st}$ HF bed of constructed wetlands, the decomposition velocity of SS was rapid than that for BOD, COD, T-N and T-P in constructed wetland for treating hydroponic wastewater. The decomposition velocity (K; $day^{-1}$) of pollutants in $2^{nd}$ HF bed of constructed wetland were higher in the order of T-P ($0.52day^{-1}$) > BOD ($0.28day^{-1}$) > COD ($0.15day^{-1}$) > T-N ($0.06day^{-1}$) > SS ($0.10day^{-1}$). In $2^{nd}$ HF bed of constructed wetlands, the decomposition velocity of T-P was rapid than that for BOD, COD, SS and T-N in constructed wetland for treating hydroponic wastewater.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.434-441
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• 2011

To improve T-N and T-P removal efficiencies, removal efficiencies of pollutants in full-scale livestock wastewater treatment plant by natural purification method with water plant filtration and activated sludge beds were investigated under different re-injection rates and injection methods of livestock wastewater. The removal rates of COD, SS, T-N, and T-P in effluent in full-scale livestock wastewater treatment plant were in the order of 30% < 70% ${\leq}$ 100 % at different re-injection rates. The removal rates of pollutants in effluent in full-scale livestock wastewater treatment plant were higher as re-injection rate of livestock wastewater increased. Removal rates of COD, SS, T-N, and T-P by continuous injection were slightly higher than those by intermittent injection method in full-scale livestock wastewater treatment plant. Removal rates of COD, SS, T-N, and T-P by continuous injection method in full-scale livestock wastewater treatment plant with water plant filtration and activated sludge beds were 99.5, 99.8, 99.0 and 99.8%, respectively.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.66-77
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• 2019

The present study investigated pine trees, which forms a major plantation species in Korea, with the objective of improving the survival rate of pine trees after planting. Growth responses and characteristics were assessed by controlling the level of fertilizer application, which is a basic controlling the growth of pine seedlings, to identify the optimal fertilization treatment. Pine tree seedlings were grown in 104 containers and were examined 8 weeks after planting. Stem height and were measured at 4-week intervals. In terms of fertilization treatment for 1-0 pine seedlings, the treatment group with gradually-increasing fertilizer concentration ($500{\rightarrow}1000{\rightarrow}1000{\rightarrow}1000mg{\cdot}L^{-1}$) had the biggest increase in stem height and diameter at the root. The survey results indicated that the increased concentration treatment group and the gradually-increasing concentration treatment group had more growth compared with that in the fixed concentration treatment group. The gradually-increasing concentration treatment group ($500{\rightarrow}1000{\rightarrow}1000{\rightarrow}1000mg{\cdot}L^{-1}$) had the highest total dry matter production. Nine weeks after fertilization, the tips of the pine leaves turned yellow in the fixed concentration treatment group ($3000mg{\cdot}L^{-1}$). The same phenomenon was observed in the treatment group in which the concentration was increased to $2000mg{\cdot}L^{-1}$, and in the gradually-increasing concentration treatment group, when the concentration was raised up to $2000mg{\cdot}L^{-1}$. We concluded that the optimal fertilization conditions for producing healthy pine 1-0 seedlings involve fertilizing once a week with Multifeed 19 at $500mg{\cdot}L^{-1}$ during the seedling period, Multifeed 19 at $1000mg{\cdot}L^{-1}$ during the rapid growth period, and Multifeed 32 at $1000mg{\cdot}L^{-1}$ during the maturation period.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.3
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• pp.123-135
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• 2006

Spatial variability and distribution map of soil properties and the relationships between soil properties and crop yields are not well characterized in agroecosystems that have been land leveled to facilitate more cultivation of the new reclaimed sloping highland. Potato, onion, carrot, Chinese cabbage and radish were grown on the coarse sandy loam soil in 2004. Soil moisture content, soil penetration resistance and crop yield were sampled in the $10m{\times}50m$ field consisted of five plots. Sampling sites of each cultivation plot were 33 for the soil moisture, 11 for the soil penetration and 33 for the crop yield. The results of semivariance analysis, most of models were shown spherical equation. The significant ranges of each spatial variability model for the soil moisture, soil penetration and crop yield were broad as 33-35 meters in the potato cultivation plot, and that in the Chinese cabbage cultivation plot was narrow as 5-6 meters. The coefficient of variances (C.V.) of moisture, penetration and yield were various from 14 to 59 percents in five cultivation plots. The highest C.V. of potato yield was 59 percents, and that of the radish cultivation plot was as low as 14 percents. The required sample numbers for the determination of soil moisture content, soil penetration resistance and crop yield with error 10% at 0.05 significant level were ranged 8-40 for soil moisture, 7-25 for soil penetration and 424-4,678 for crop yield. The variogram and distribution map by kriging described field characteristics well so that the spatial variability would be useful for soil management for better efficiency and precision agriculture in the reclaimed highland.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.298-310
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• 2007

This study compared the correlation between the accumulated copper content in earthworms and the copper concentration rate of soil measured using several methods to extract heavy metals from soil. For the experiment, a microcosm soil test was carried out using copper contaminated soil from the vicinity of copper-roofed buildings and earthworms (Eisenia fetida). Soils from the study area were used to produce 6 treatments; control, 1C (contamination level with the lowest treated copper concentration rate), 2C, 4C, 8C, and 16C (contamination level with the highest treated copper concentration rate). Microcosm soil test using the 6 treatments proved that as the copper content in soil and the experiment time increased, the growth rate of and the accumulated copper concentration rate in earthworms increased as well. The degree of the increase corresponded to the order of the treated copper concentration levels in microcosm soils. Standard method of the ministry of environment and EPA method 3051 were used to obtain the copper concentration in soil and the total copper content in soil, respectively. The correlation coefficient (r) of 0.9875~0.9993 between the copper content extracted by the standard method and the total copper content shows high positive correlation. The correlation coefficient of the copper content in soil extracted by the standard method and the accumulated copper content in earthworms, and the correlation coefficient of the total copper content in soil and the accumulated copper content in earthworms were ranged from 0.9193 to 0.9728 and from 0.9282 to 0.9844, respectively, showing highly significant positive correlation. Due to the high correlation between the copper concentration in soil and the accumulated copper content in earthworms, it is concluded that earthworms are suitable to be used as biological indicator species or for bio-monitoring against copper contamination of soil.