• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.257-266
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• 2006

Studies were carried out to evaluate the effect of liquid pig manure on the production of Japanese millet, the chemical characteristics of pasture soil and leaching water. The study was undertaken from June to September 2005. Randomized complete block design was used to allot four treatments: T1 (no fertilizer), T2 (N : 200 kg/ha, p : 150 kg/ha, K : 150 kg/ha), T3 (liquid pig manure containing 1.7% DM 200 kg N/ha) and T4 (liquid pig manure containing 7.0% DM 200 kg N/ha). Leaching water was sampled at 21 August (1st time), 9 September (2nd time) and 26 September (3rd time), 2005, respectively. No significant differences in the dry matter yield of Japanese millet was found among the four treatments, whereas the plant lengths of Japanese millet were higher in the T2, T3 and T4 than in T1 (p<0.05). Nitrogen, P and K uptake of J. millet tended to be influenced by application of chemical fertilizer or 7.0% DM liquid pig manure compared with T1 or 1.8% DM liquid pig manure. The organic matter (OM) content of soil was higher in T2, T3 and T4 than in T1. Na content was highest in T3 among the four treatments. $NO_{3^-}N\;or\;NH_{4^-}N$ content in leaching was not different among the four treatments. $SO_4$ content in leaching water sampled in 1st time was high in T4, but in T3 from 3rd time (p<0.05). Cl, Mg and Na contents were high in leaching water sampled in the 1st time from T4, whereas high in those from T3 in 2nd or 3rd time. Results show that the application of a high DM liquid pig manure is not better for producing Japanese millet and improving the properties of pasture soil than a low DM liquid pig manure. However, the contents of $SO_4$, Cl, Mg and Na in leaching water sampled in 1st time were high in a high DM liquid pig manure.

• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.157-168
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• 2020

The sensitivity of forest soil to acidification in the Republic of Korea (ROK) was evaluated based on pH_H2O, cation exchange capacity (CEC), and base saturation (BS). Sensitivity to acidification was categorized into three grades: adequate level (AL, pH ≧ 4.2, CEC ≧ 15cmol/kg, BS ≧ 15%), caution level (CL, at least one indicator is below AL), and severe Level (SL, all three indicators are below AL). Soil samples were collected from the 65 stationary monitoring plots (40 × 40 ㎢), distributed throughout ROK. Only 19% of soil samples were classified as AL, while 66% and 15% were CL and SL, respectively. The median of pH_H2O, CEC, BS, and Ca/Al indicator in AL soils was pH 4.64, 20.7cmol/kg, 29%, and 6.3, respectively. Moreover, BC_ex (K⁺, Mg²⁺, Ca²⁺) and available phosphorus (AP) concentration compared with a threshold value and molar ratio of BC_ex and AP to total nitrogen (TN) was high. This indicates that AL soils have a good nutrient condition. The molar Ca/Al ratio, an indicator for toxicity of exchangeable aluminum (Al_ex), was more than 1, indicating no negative impact of Al_ex on plant growth. On the contrary, the median of pH_H2O, CEC, and BS in SL soils was pH 4.02, 13.2cmol/kg, and 10%, respectively. The Ca/Al index was less than 0.6, which indicates that negative impacts of Al_ex on plants were high. Furthermore, both the concentration of BC_ex in SL soils and the BC_ex/TN ratio were the lowest among the three acidity degrees. This shows that SLsoils can be degraded by soil acidification compared with less acidic soils.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.203-210
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• 2001

In order to environmentally use wood chips manufactured from low valued forest resources by forest tendering, wood chips were used for the evaluation on chips characteristics, decomposition capability of organic wastes, and field experiment and determination of conditions for decomposer. Bioclusters manufactured by Cryptomeria japonica, commercially available wood chips in Japan, showed higher pore ratio, water reservation and water resistance, and higher cellulose content with lower hot water solubles than domestic wood chips. The useful size of wood chips for swine manure decomposition was 10 (length) ${\times}$ 5 (width) ${\times}$ 2 (thickness) mm, and cellulose contents and alkali solubles of Pinus densiflora and Populus tomentiglandulosa were similar to those of bioclusters. According to the decomposition ratio depending on wood species, it was ordered as Pinus densiflora > Pinus koraiensis > Cryptomeria japonica. The swine manure decomposition ratio depending on treatment hours by Pinus koraiensis was constant with the ratio of 15 to 16 g per hour by 1 kg of chip, indicating of daily swine decomposition amount of 390 kg by 1 ton of chips which was equal to the amount of daily swine manure production by 70 swines. Analyzing by long term used wood chips during 40 days treatment, the treated wood chips characteristically showed stable total nitrogen content, suitable pH, high accumulation of inorganic contents such as calcium, phosphorus, potassium and sodium, and no odor. During winter, the inner temperature of decomposer was kept at $43^{\circ}C$, but air bubble was occurred due to high pH and viscosity of swine manure. The most appropriate mixing ratio between wood chips and swine manure was 1 versus 2 or 3, and at more than ratio 1 versus 3, ammonia gas was caused because of anaerobic fermentation status by high moisture content of wood chips. The mixing interval of decomposer was 3 mins. per hour for the best swine decomposition.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.184-192
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• 2007

This study was to evaluate ecological health of Sumjin River during April${\sim}$June 2006. The ecological health assessments was based on the Index of Biological Integrity (IBI), Qualitative Babitat Evaluation Index (QHEI), and water chemistry. For the study, the models of IBI and QHEI were modified as 10 and 11 metric attributes, respectively. We also analyzed spatial patterns of chemical water quality over the period of $2002{\sim}2005$, using the water chemistry dataset, obtained from the Ministry of Environment, Korea. In Sumjin River, values of IBI averaged 33 (n= 12), which is judged as a "Fair${\sim}$Good" condition after the criteria of Barbour at al. (1999). There was a distinct spatial variation. Mean IBI score at Site 5 was estimated as 40, indicating a "Good" condition whereas, the mean at Site 3 was 23, indicating a "Poor${\sim}$Fair" condition. Habitat analysis showed that QHEI values in the river averaged 109 (n=6), indicating a "Marginal" condition after the criteria of Harbour et al. (1999). Values of BOD and COD averaged 1.3 mg $L^{-1}$ (scope: $0.9{\sim}1.8$ mg $L^{-1}$) and 3.3 mg $L^{-1}$ (scope: $2.8{\sim}4.0$ mg $L^{-1}$), respectively during the study. It was evident that chemical pollutions by organic matter were minor in the river. Total nitrogen (TN) and total phosphorus (TP) averaged 2.5 mg $L^{-1}$ and 0.067 mg $L^{-1}$, respectively, and the nutrients did not show large longitudinal gradients between the upper and lower reach. Overall, dataset of IBI, QHEI, and water chemistry suggest that river health has been well maintained, compared to other major watersheds in Korea and should be protected from habitat disturbance and chemical pollutions.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.785-792
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• 2006

The characteristics of alcohol fermentation using sweet persimmon juice were studied in static fermentation in an effort to develop new types of functional wine. The yeast strain Saccharomyces cerevisiae KCCM 12650 was selected for use in the fermentation of sweet persimmon juice. Attempts were made to modify the sweet persimmon juice in order to find suitable conditions for alcohol fermentation. The modified sweet persimmon juice (pH 4.0) that was most suitable for alcohol fermentation contained $24^{\circ}Brix$ of sugar supplemented with sucrose as a carbon source and 0.5 g/L of $(NH_4)_2HPO_4$ as a nitrogen source. After 5 days of fermentation at $25^{\circ}C$, 12.8% of alcohol was produced from the modified juice and its pH was slightly decreased to 3.9. Browning of the wine was observed during storage due to the oxidation of phenolic compounds. The initial browning of 0.08% at $OD_{420}$ after fermentation increased to 0.40 during storage for 11 weeks at room temperature. The addition of $K_2S_2O_5$ was effective in delaying the browning of the wine. The browning of the wine decreased to 0.25 at $OD_{420}$ with the addition of 200 mg/L of $K_2S_2O_5$. The wine produced in this study contained some organic acids such as malic acid (6.82% g/L) and succinic acid (1.40 g/L), some minerals such as $K^+$ (947.8 mg/L) and $Mg^{2+}$ (36.4 mg/L), as well as soluble phenolics (779 mg/L of gallic acid equivalent). Schisandra fruit was added to the sweet persimmon juice during alcohol fermentation in order to improve the sour taste and flavor. The best sensory quality (taste, flavor, and color) was obtained by adding 0.5% schisandra fruit.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.324-332
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• 2014

In order to reveal the long-term variations of water quality in Jinhae Bay, water qualities had been monitored at 9 survey stations of Jinhae Bay during 2000~2012. The surface and bottom waters concentrations of chemical oxygen demand (COD), dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and chlorophyll-a (Chl.-a) were higher at the survey stations of Masan Bay than the stations of other Bays. Especially, station 1 which is located at the inner area of Masan Bay had the highest values in the concentrations of COD, DIN, and Chl.-a because there were terrestrial pollutant sources near the station 1 and sea current had not well circulated in the inner area of Masan Bay. In factor analysis, the station 1 also had the highest factor values related to factors which increase organic matters and nutrients in surface and bottom waters of Masan Bay. However, the stations (st.5, st.6, st.7, st.8, and st.9) of other Bays had lower values of the factors. In time series analysis, the COD concentrations of the bottom waters at 8 stations except for station 1 distinctly decreased. However, the COD concentrations of the surface waters showed no distinct decrease trends at all stations. In the concentrations of nutrients (DIN and DIP) of both surface and bottom waters, there were tremendous decrease trends at all stations. Therefore, these distinct decrease trends of the COD in bottom waters and the nutrients in surface and bottom waters of Jinhae Bay could have been associated with water improvement actions such as TPLMS (total pollution load management system).

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.285-294
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• 1999

Changes of chemico-physical properties and mturitiy during pig manure composting were analysed using three kinds of bulking agents with rice hull(T1), rice hull and extruding hull mixture (T2, 1:1, v/v), and extruding hull(T3). During composting process, temperature of T1, T2 and T3 were maintained over $50^{\circ}C$ for 31, 21, and 35 days respectively. Organic matter content of each treatment was decreased from 82.2%, 82.0%, and 82.8% to 70.5%, 68.9% and 69.7% and pH increased to 8.85, 9.91, and 8.80, respectively. Total nitrogen content of all treatments gradually decreased, but C/N ratio, phosphorous, and potassium content did not, show any changes during composting process. Both germination rate and early growth were tested using radish seeds for composting maturity. From those results, it was concluded that all treatments were stabilized after 45th day and extruding hull(T3) added compost was superior to others. The test of suppressive effect showed that all treatment have no effect against Fusarium oxysporum, Alternaria altemata, Botrytis cinerea. Compost supplemented with rice hull showed an inhibitory effect after 30th days, while compost supplemented with rice hull and extruding hull(T2) had an inhibitory effect during all period against Rhizoctonia solani. But treatment with extruding hull(T3) added compost did not have any inhibitory effect against Rhizoctonia solani. Only 63th samples in T1 and T2 treatment showed inhibitory effect against Colletoerichum gloeosporioides. However, T3 did not. Suppressive effect of extracts from 67 kinds of composts was investigated in vitro against plant pathogens, such as Fusauum oxysporum. Alternaria alternata, Colletotrichum gloeospoioides, Rhizoctonia solani, and Botrytis cinerea. Thirty two of them showed inhibitory effect against more than one phytopathogen, nine against one pathogen, four against two, six against three, six against four, and seven against five.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.232-238
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• 1999

Effects of animal manure application on the yield of crops were studied. Red pepper (1995) and Chinese cabbage (1996) were planted in pot with chicken, cow and pig manure application at $1.6mg\;ha^{-1}$, $3.2mg\;ha^{-1}$. Silage corn was grown in pot at 100%, 75%, 50% and 0%of recommended chemical fertilization rate among previously manure applied soils to predict the reduction of fertilizer. Results were as follows: Chemical properties of manure applied soils for two years were increased as pH 6.1~7.1, OM $17.1{\sim}23.7g\;kg^{-1}$, $P_2O_5$ $370{\sim}1.058mg\;kg^{-1}$, while those of chemical fertilizer applied soils were pH 5.8. OM $16.9g\;kg^{-1}$, $P_2O_5$ $249mg\;kg^{-1}$. Exchangeable cation and $P_2O_5$ content were increased in chicken manure applied soils than those in manure applied soils. Red pepper yield in manure applied pots was 121~192% compared to that in only chemical fertilizer applied pot. Effects of manure application was in the order of pig, chicken and cow manure. Chinese cabbage yield in manure applied pots was 55%~111% compared to that in chemical fertilizer applied pot. Effects of manure application were higher in red pepper than in Chinese cabbage. Fresh corn yield showed no significance between reducing 0% and 25% of recommend fertilization rate in previously manure applied plots, except in previously cow manure applied plots at $1.6mg\;ha^{-1}$. Fresh corn yield showed a positive correlation ($r=0.75^{**}$) with organic matter content and showed a positive correlation ($r=0.85^{**}$) with total nitrogen in untreated plot among previously manure applied soils.

• Journal of Animal Environmental Science
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• v.14 no.3
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• pp.201-210
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• 2008

Farmers directly spread the livestock manure compost on their arable land as an organic fertilizer. However, there are some difficult problems to solve. first, we are unsure of whether the livestock manure compost can meet the nutritional demand of plant. Second, application of the current powered livestock manure compost to crop land is very difficult work due to heavy weight of compost and its powdered shape. For this reason, this study was carried out to develope high quality pelletized livestock manure compost. In pelletizing process with composted manure, the optimal water content for pelletizing was around 30$\sim$40%. When rice bran was mixed with 5% as a bonding agent on volume basis, the pelletizing effect was remarkably improved. On a dry matter basis, the contents of N and P of manure compost were 1.31%, and 0.58%, respectively. After pelletizing, the contents of compost pelleted were 1.37% and 0.54%, respectively. The same parameters of pelletized compost made by screw type Instrument were 1.37% and 0.53%, respectively. The other hand, N and P content of pelletized compost made by pellet mill type instrument were 1.06% and 0.18%, respectively.

• Korean Journal of Remote Sensing
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• v.32 no.3
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• pp.221-234
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• 2016

In Korea, most industrial parks and major cities are located in coastal areas, which results in serious environmental problems in both coastal land and ocean. In order to effectively manage such problems especially in coastal ocean, water quality should be monitored. As there are many factors that influence water quality, the Korean Government proposed an integrated Water Quality Index (WQI) based on in situmeasurements of ocean parameters(bottom dissolved oxygen, chlorophyll-a concentration, secchi disk depth, dissolved inorganic nitrogen, and dissolved inorganic phosphorus) by ocean division identified based on their ecological characteristics. Field-measured WQI, however, does not provide spatial continuity over vast areas. Satellite remote sensing can be an alternative for identifying WQI for surface water. In this study, two schemes were examined to estimate coastal WQI around Korea peninsula using in situ measurements data and Geostationary Ocean Color Imager (GOCI) satellite imagery from 2011 to 2013 based on machine learning approaches. Scheme 1 calculates WQI using estimated water quality-related factors using GOCI reflectance data, and scheme 2 estimates WQI using GOCI band reflectance data and basic products(chlorophyll-a, suspended sediment, colored dissolved organic matter). Three machine learning approaches including Random Forest (RF), Support Vector Regression (SVR), and a modified regression tree(Cubist) were used. Results show that estimation of secchi disk depth produced the highest accuracy among the ocean parameters, and RF performed best regardless of water quality-related factors. However, the accuracy of WQI from scheme 1 was lower than that from scheme 2 due to the estimation errors inherent from water quality-related factors and the uncertainty of bottom dissolved oxygen. In overall, scheme 2 appears more appropriate for estimating WQI for surface water in coastal areas and chlorophyll-a concentration was identified the most contributing factor to the estimation of WQI.