• Journal of Ecology and Environment
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• v.37 no.1
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• pp.13-19
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• 2014

The effect of different turnover time of water on the decomposition of emergent macrophyte litter (Zizania latifolia Griseb.) was investigated using a microcosm experiment. Microcosm treatment represented different turnover time of water; 1, 2, 4 and 8 weeks. The litterbags from each treatment were retrieved every 2 weeks until the 8th week and the water simultaneously sampled with the litterbag. The dry weight and the content of major cations in the litter, and the content of available N, P, and major cations in the water were analyzed. Dry weight loss after 8 weeks indicated the lower decay rates under the condition of short turnover time of water. Major cations from the litter and the water showed that the leached amounts of K and Mg from the litter were highest in the 2nd week and dramatically decreased from the 4th week. The dynamics of available nitrogen and phosphorus in the water showed that as the water turnover time was getting longer, the amounts of available nitrogen and phosphorus remained higher. These results suggest that wetlands with longer turnover time of water could maintain the increased nitrogen and phosphorus and no outflow of the nutrients could cause eutrophication problem.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.86-92
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• 2012

To promote the practical use of livestock manure compost (LC) for paddy rice cultivation, the fertilization efficiency of nutrients in LCs was investigated compared to that of chemical fertilizer. This experiment was conducted at rice field in Hwaseong, Korea, with 6 treatments by each of 3 kinds of tested LCs, cattle manure compost (CaC), swine manure compost (SwC) and chicken manure compost (ChC). The treatments consisted of 3 application levels of LCs and 3 chemical fertilizer treatments having the same application levels with LCs. $NH_4$-N content in soil became higher according to the increase in the urea application rate, while it became lower in LC plots than in urea plots, and statistically had no significant difference among LC plots. There was a close relationship between phosphate fertilization rate and the increment of soil available phosphate content after experiment resulting y = 0.1788x - 6.169 ($R^2=0.9425$) when applied fused superphosphate fertilizer, and y = 0.0662x - 2.689 ($R^2=0.9315$) when applied LC at the equivalent rates to phosphate input (x: phosphate application rate, kg $ha^{-1}$, y: increment in soil available phosphate content, mg $kg^{-1}$). And from these two equations, the correlation on the phosphate application rate between fused superphosphate fertilizer and LC could be obtained as y = 2.7056x - 52.492 (x: $P_2O_5$ application rate of fused superphosphate, kg $ha^{-1}$, y: $P_2O_5$ application rate of LC, kg $ha^{-1}$). Plant height, number of tillers, nutrients uptake by rice, and rice yield showed higher levels in N 100% and N 150% application plots of chemical fertilizers, while every LC plots exhibited lower values and no significant difference among them. Relative nitrogen fertilization efficiencies of LCs compared to urea was 12.3% for CaC, 8.8 for SwC and 24.6 for ChC, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.33-39
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• 2009

The practice of supplying nutrients for paddy soil with sustaining human health and ecological soundness is to utilize indicators considering soil chemical reactions. The long-term basis experiment of fertilizer and amendment of paddy soil and an experiment of yield response of soil types on nitrogen level from 2000 till 2002were used to search indicators of nutrient supplying capacity related to soil chemical reactions. Chemical reactions of paddy soil was composed of dissociating and/or adsorbing nutrients and of decomposing soil organic matter (SOM) into $H^+$, $e^-$, $CO_2$ in paddy soil. The indicators of nutrient supplying capacity, which were established by considering soil chemical reactions, were SOM or soil protein for nitrogen and available phosphate for phosphorus and cation exchangeable capacity (CEC) and exchangeable potassium for potassium. Korea has used fertilizer recommendation equations established with the indicators of nutrient supplying capacity for paddy soil.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.5
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• pp.466-472
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• 2016

The objectives of the study were to analyze the various nutrient contents of ready-to-use-supplemental-food (RUSF) developed with Eastern African ethnic plants and compare them with commercially available supplemental food (CASF) for infants. RUSF was made with three African plants, including Ficus sur, Amaranthus caudatus, and Prosopis juliflorafa and locally available food ingredients in DR Congo and Ethiopia and was cooked at $180^{\circ}C$ for 20 min in a conventional oven. Macronutrients were analyzed by the AOAC method. Contents of 17 amino acids were analysed with amino acid analyzer, and vitamin $B_1%$ niacin, vitamin $B_6$, and vitamin C were analyzed with HPLC. Isomers of vitamin E were analyzed by GC-FID. The price of RUSF was 0.133 USD per 100g. Contents of macronutrients were not significantly different between developed RUSF and CASF. Results of amino acid analysis showed that most amino acid contents were similar or higher in RUSF compared with CASF. However, glutamic acid and lysine contents were less in RUSF than in CASF. Vitamin E and vitamin $B_1$ contents were more than five times higher in RUSF (22.40, 6.26 mg/100 g, respectively) than in CASF (4.00, 0.80 mg/100 g, respectively). Niacin was about three times higher while vitamin $B_6$ was almost 20 times higher in RUSF than in CASF. However, ascorbic acid was significantly lower in RUSF (3.43 mg/100 g) than in CASF (42.08 mg/100 g). Our study found that the developed localized RUSF showed higher nutrient contents in most micronutrients analyzed except for ascorbic acid. Out of 17 amino acids, glutamic acid and lysine contents in RUSF were less than in CASF. Therefore, further study is needed in order to improve these nutrients contents.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.5
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• pp.105-113
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• 2018

In this study physical and chemical characteristics of rice straw ash (RSA) were analyzed in agricultural by-products such as the characteristics of soil pH, electric conductivity (EC), total phosphorus (T-P), available phosphate (Avail-P), and cation exchange capacity (CEC). The results showed that RSA is of mainly C in 95.74% and followed by Si > Al > P > Mg > K > Ca. The pH of RSA was high near 11 and the T-P concentration was $2,322.38{\pm}10.35mg/kg$. The specific surface area of RSA was $123.50m^2/g$, which was much lower than that of biochar. The X-ray diffraction (XRD) analysis indicated that RSA were C and Si based crystalline. TCLP and KSLT test results implied that the heavy metal concentrations were below the environmental standards and would not impose the risks. T-P concentration increased from $225.59{\pm}12.69mg/kg$ to $593.39{\pm}17.36mg/kg$ along with RSA mixing ratio to soil from 0% to 15%. Both pH and EC values were increased with the increase of RSA ratio. The changes in Avail-P and CEC were not when RSA mixing ratio was 1%. whereas the Avail-P concentration was slightly increase when the mixing ratio was more than 5%. Additional investigation considering receiving soil characteristics based on the results of this study would help effective application of RSA to soil.

• Journal of Nutrition and Health
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• v.40 no.2
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• pp.172-181
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• 2007

This study was performed to evaluate served menu in Korean temples. Among available temples in the nation, 34 temples were carefully selected considering location and the gender characteristics. A five consecutive day menu was collected to analyse by interview between Jan 2004 and Aug 2004. Mean energy content of menu was 1633.8 kcal, with 67.3% of energy supplied by carbohydrate, 14.8% by protein and 17.9% by fat. Beans and bean products were the major contributing dishes for most nutrients. Contents of most nutrients except energy, protein and vitamin B were higher than RDA. Nutrient adequacy ratio (NAR) were 0.9-1.0 and mean adequacy ratio (MAR) was 0.9 for temples. Total number of dishes from menu was 7.3. Dietary variety score (DVS) was 26.4 and buddhist monk temples offered more diverse foods than buddhist nun temples. KDQI (Korean diet Quality Index), overall diet quality index were 0.67 and those of buddhist nun temples were better than those of buddhist monk temples. From the result of this study it was concluded that the temple diet is nutritionally well balanced, rich in dietary fiber and low in cholesterol. So it can be a healthy diet for the modern person. This is the very first study attempting the nationwide investigation of temple diet in Korea. It will be used as fundamental data to improve quality of diet to prevent modern chronic disease.

• Nutritional Sciences
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• v.7 no.2
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• pp.88-91
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• 2004

New Dietary Reference Intakes (DRIs) forthe United States and Canada have recently been set for both macronutrients and micronutrients, and are likely to be of interest to health professionals in Korea as well. DRIs are now available for nutrients that did not have Recommended Dietary Allowances set in the past (amino acids, n-3 and n-6 fatty acids, total fiber, added sugar, choline, boron, nickel, and vanadium). Furthermore, the units for the DRIs do not always match those traditionally carried on food composition tables (FCTs). FCT developers will also need to consider carrying new variables to allow the calculation of folate intake in $\mu$g of dietary folate equivalents, vitamin E intake as mg of a-tocopherol (not as mg of a-tocopherol equivalents), and vitamin A intake as $\mu$g of retinol activity equivalents (not as $\mu$g of retinol equivalents). Because the new recommendations for upper levels of intake sometimes refer to a specific form or source of a nutrient, nutrients occurring in foods must be separated from added or supplemental forms for vitamin E, niacin, and folate; pharmacological magnesium must be carried as a separate variable; and preformed vitamin A must be separated from vitamin A from carotenoids. For more information on the DRIs, see: www.nap.edu.

• 한국해양학회지
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• v.12 no.1
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• pp.13-32
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• 1977

In order to determine the distributional ecology, and to investigate factors influencing these features, the diatom communities in plankton at depths of one, twenty-five, fifty, and seventy five meters in the area were studied and measured over a fifteen month of period. Measurements of environmental factors including temperature and salinity and algal nutrients such as phosphate, silicate, nitrate, and ammonia were also made at the same depths and locations. The results indicate that the size of diatom communities and the species population changes were heavily dependent upon to season and location parameters as well as nutrient concentrations and hydrographic factors. Major factors influencing population distributions varied with principal species responsible for dominant species and species sucession. Two distinct distributional patterns in total diatom crop were observed in the study area. Maximum standing crop observed during spring and/or summer were related to the concentration of nutrients available at the onset of the spring bloom on a large scale. On a small scale, however, the distributions of total diatom standing crops were significantly correlated with both season/location factors and with hydrographic parameters as well. Vertical stratification of diatoms was observed only in the presence of the thermocline in the water column. Within the study area there was some seasonal consistancy in the composition of the species groups. However, some species association in these environments may vary with the change of season.

• Journal of environmental and Sanitary engineering
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• v.6 no.2
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• pp.17-31
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• 1991

The effects of environmental agents on health are great concern for all. It was recognized that each human has differential susceptibility to environmental effects. Susceptibility are changed by many factors includin gdevelopmpntal processes, genetic factors, nutritional stratus, preexisting disease conditions, life style and personal habits. Of all factors nutritional factors seem to be the area most modifiable. Consequently, It is an area that must be more thoroughly evaluated. In this paper, nutrient and environment interactions are reviewed briefly with published literatures. This paper deals with the influence of micronutrients(energy, protein and fat), Vitamins (vitamin 4, vitamin B-complex, vitamin C, vitamin D and vitamin I) and Minerals(calcium, iron, selenium, zinc and other minerls) on environmental effects. The role of arch nutrient was assessed in modifyine the expression of environmental pollutant toxicity with available litertures. In each nutrient section, the effect of environment was considered in following agents : heavy metals(lead, cadmium, mercury, silver and etc), inorganic agents(nitwits, sulfite, fluoride and etc), organic agents(benzene, carbon tatra-chloride, aflatoxin, auto dye, dialbrin etc), Irritant gas(ozone, carbon monooxide and etc), physical agents(X-irradiation, ultra violet, temperature and noise) and insectcides. The extent to which nutritional status modifies environmental effects 3nd its converse, how envirollments affects nutritional status is very complex. In deed, at the present time there are more than 50 chelnical/phycical agents that affect the nutrient metabolism and/or have their toxicity either directly diminished or enhanced by nutrients of those agents, small number of agents for each nutrients have sufficient evidence to warrant any reasonable degree of confidence in their hypothesized associtation. With these information at this present time it is hard to conclude that the recommended dietary allowance for each nutrient should be reconsidered.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.5
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• pp.160-170
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• 2003

A pilot study was performed to examine the feasibility of intermittent slow sand filtration for agricultural reuse of reclaimed water. The effluent of biofilter for 16-unit apartment was used as influent to the slow sand filtration system at 0.6 $m^3$/day loading rate using 15 seconds spray in every 10 minutes on the about 1 $m^2$ surface area and 0.5 m depth. The influent concentrations of total coliform (TC), fecal coliform (FC) and E. coli were in the range of 10.000 MPN/100 mL. and they were reduced to less than 1,000 MPN/100 mL after filtration with average of 320, 270, and 154 MPN/100 mL, respectively, showing over 95 % removal. Turbidity and SS were improved effectively and their average concentration was reduced to 0.8 NTU and 1.7 mg/L, respectively, and removal rate was about 50 %. Average BOD and COD concentrations were also reduced substantially to 2.6 and 25.8 mg/L with about 55 and 21 % removal rate, respectively. Nutrients removal was relatively low and removal rate for T-N and T-P was low however, remaining nutrients might be beneficial and less concerned in case of agricultural reuse. The concentration of biofilter effluent used in this experiment was in the range of secondary treatment effluent but slightly stronger than the one from existing wastewater treatment plants (WWTPs). Therefore, intermittent slow sand filtration might be also applicable to the effluent from WWTPs as long as its agricultural reuse is available. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, the intermittent slow sand filtration was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water. This paper is a preliminary result from pilot study and further investigations are recommended on the optimum design parameters before full scale application.