• Korean Journal of Soil Science and Fertilizer
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• v.28 no.4
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• pp.312-318
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• 1995

To investigate the effect of N split application on the increasing ratio of yield and the yield of rice, urea and slow-releasing complex for sideband placement of fertilizer were applied in Jeonbuk series of Honam plain area. Increasing ratio of yield by N split application was higher in puddled drill seeding (PDS) than flooded direct seeding surface (FDSS) under split application of 40-0-30-30% and 70-0-0-30% at basal, 3 leaf, 5 leaf and panicle initiation stage, respectively. It was also higher in LCU application of 70 % of total urea amount than urea application but was not different between two methods of seeding in urea application. Nitrogen ratio transfered to rough grain of rice was higher in FDSS than PDS, errespective of methed of split application, except for the split application of 0, 40, 30 and 30% N fertilizer at basal, 3 leaf, 5 leaf and panicle initiation stage, respectively. Nitrogen amount outflowed by artificial drainage for paddy field drying in a day after application of fertilizer was 1,134g/10a in PDS. $NH_4-N$ incerased higher in PDS than FDSS under split application of urea, while was versa under LCU application.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.339-346
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• 1986

A study on eutrophication in the downstream of the Nakdong River was conducted from October 1983 to September 1984. Nutrients concentration of the samples in this area was usually high and the nitrogen ratio to the phosphorus was as very high as $63.5{\sim}119.6$. The concentration of nutrients was in the range of $0.22{\sim}173{\mu}g-at/l$ for ammonia nitrogen, $26.7{\sim}187{\mu}g-at/l$ for nitrate nitrogen, $1.07{\sim}8.22{\mu}g-at/l$ for nitrite nitrogen, $58.7{\sim}231{\mu}g-at/l$ for total inorganic nitrogen and $0.44{\sim}4.43{\mu}g-at/l$ for phosphate phosphorus. The concentration of chlorophyll-a was in the range of $1.8{\sim}75.2\;mg/m^3$. Correlationship between concentration of nutrients and chlorophyll-a was not found. The concentrations of total suspended solid were in the range of $10.7{\sim}45.9\;ppm$, and $16.2{\sim}35.2\%$ of the total suspended solid was consisted of volatile suspended solid. According to the state of lacustrine nutrition, the state of the downstream of Nakdong River was equivalent to the eutrophication state in term of chlorophyll-a and inorganic nitrogen, and mid-nutritional state in term of phosphate.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.642-648
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• 2012

To evaluate the water quality in Juksancheon constructed wetlands for treating non-point source pollution, the removal rates of nutrients in water and the total amounts of T-N and T-P uptakes by water plants were investigated. Chemical characteristics of T-N and T-P in sediment were investigated. The concentrations of BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), SS (Suspended Solids), T-N and T-P in inflow were 0.07~1.47, 0.60~2.65, 0.50~4.60, 1.38~6.26 and $0.08{\sim}0.32mg\;L^{-1}$, respectively. The removal rates of BOD, COD, SS, T-N, and T-P were -10, 51, 66, -3 and 5%, respectively. The maximum amount of T-N uptake by water plants in August was $368.7mg\;plant^{-1}$ in the $2^{nd}$ treatment stage by Nymphoides peltata, $1314.6mg\;plant^{-1}$ in the $3^{rd}$ treatment stage by Iris pseudacorus, $1160.4mg\;plant^{-1}$ in the $4^{th}$ treatment stage by Nymphaea tetragona GEORGI, respectively. The maximum amount of T-P uptake by water plants in August was $121.7mg\;plant^{-1}$ by Nymphoides peltata in the $2^{nd}$ treatment stage, $268.7mg\;plant^{-1}$ by Iris pseudacorus in the $3^{rd}$ treatment stage and $212.0mg\;plant^{-1}$ by Nymphaea tetragona GEORGI in the $4^{th}$ treatment stage, respectively. Organic matter contents in sediments were not different. Contents of T-N and T-P in sediments were higher in spring. Microbial biomass C:N:P ratios in sediments in spring, summer, autumn and winter were 117~140:1~4:1, 86~126:5~6:1, 68~101:2~6:1 and 47~138:2~4:1, respectively. We could conclude that Juksancheon constructed wetlands show high removal efficiencies of COD and SS. However, improvements of management in winter season should be considered to improve the removal efficiencies of pollutants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1103-1108
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• 2005

A new type of surimi gel was prepared by adding the crab paste to the original Alaska pollock surimi, and its characteristics were determined. With increased addition of crab paste to the surimi, moisture $(81.3\;to\;79.1\%)$ and protein content $(12.2\;to\;11.6\%)$ of surimi gels slightly decreased while ash content increased compared to commercial surimi gel. Color values of surimi gels were decreased in lightness (L value, 67.3 to 63.5) but increased in redness (a value, -3.5 to 7.14). Thus, crab paste-added surimi gel was a little darked reddish product. Maximum values of breaking force and deformation of $10\%$ added surimi gel were 568g and 13.1mm, respectively. Sensory scores on color and flavor increased according to the increasing of additional ratios, whereas texture scores was maximum at $10\%$ added surimi gel. From the results of physical properties and sensory evaluation, desirable additional ratio was $10\%$. Total amino acid content (11,435 mg/100g) of $10\%$ added surimi gel was approximately $5\%$ less than non-added surimi gel, and major amino acids were aspartic acids, glutamic acid, leucine and lysine. Exceptionally, cysteine content of $10\%$ added surimi gel was 2 times higher than control (surimi gel without crab paste). Calcium and phosphorus contents of $10\%$ crab paste-added surimi gel were 172:4mg/l00g and 234.6 mg/100g, respectively, and their ratio (1:1.4) was in the optimal range in the body absorbtion efficiency.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.87-95
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• 2006

Nutritional quality of accelerated salt-fermented anchovy sauce using shrimp processing byproduct as fermenting aids was characterized and compared with commercial anchovy sauce. Four types of sauces were fermented with 0 and $10\%$ addition of shrimp byproducts ($24{\pm}2^{\circ}C$, for 270 days), and 20 and $30\%$ addition of those ($24{\pm}2^{\circ}C$, for 180 days), respectively. Extractive nitrogen content (1,431 to 1,569 mg/100g) of anchovy sauces increased as additional ratios of shrimp byproduct increased. According to the results of ommission test, the taste of all anchovy sauces was influenced by the content of free amino acids, such as mainly glutamic acid and aspartic acid. Regardless of additional ratios of shrimp byproducts, all sauces were similar in total amino acid content ($9,848\~10,324$ mg/100 g), which were 2 times higher compared to that of the commercial sauce. Proline, valine and histidine contents of sauces tend to decrease as the additional ratios of shrimp byproducts increased, whereas methionine, isoleucine, leucine, phenylalanine and lysine contents increased. Increase of some amino acids and mineral content of sauces by increasing of additional ratios was due to release from shrimp byproducts. Sensory evaluation showed that scores of color, flavor and taste of the sauce added with $20\%$ shrimp byproducts_were significantly higher than those of other sauces (p<0.05). In the useful utilization aspects of seafood processing byproducts, shrimp byproducts were good resource for accelerated fermentation and nutritional improvement in preparation of fish sauce.

• Applied Biological Chemistry
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• v.17 no.3
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• pp.219-234
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• 1974

A series of experiments was conducted to study the behavior of the phosphorus added to the soils having the high phorphorus fixing capacity derived from volcanic ash in Cheju Island. Soil samples were taken from different depths of 0-10, 10-30, and 30-50cm in six citrus orchards where heavy application of phosphate fertilizer has been practised. Various forms of phosphorus were determined and phosphorus adsorption experiments were performed. The results obtained can be summarized as follows: 1. The content of inorganic phosphorus fractions determined by the method of Chang and Jackson was: water soluble P

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.20-27
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• 1983

A series of laboratory experiment was conducted to find out the chemical composition, characterization of humic substances by physical and chemical methods and reaction of Na-pyrophosphate, $Ca(OH)_2$ and rice straw with albumin on the degradation of soil organic matter in the volcanic ask soils of the Jeju Island. Results obtained were summarized as follows: 1. The contents of organic matter, available silicon, active iron and aluminum concentration in volcanic ash the soils were remarkably higher but available phosphorous was comparatively lower than the mineral soils. In volcanic ash soil, the contents of potassium, calcium and magnessium were higher in upland soil than that of forest soil. The ratios of active $Al^{{+}{+}{+}}/Fe^{{+}{+}}$, C/P and $K/Ca^+$ Mg were apparently high in volcanic ash soils while that of $SiO_2$/O.M. was high in mineral soil. 2. The carbon/nitrogen ratio in humin, humic acid content in organic matter, and carbon contents of humin in total carbon of soil organic matter were apparently higher in the volcanic ash soils than in the mineral soils, The total nitrogen and fractions of acid or alkali soluble nitrogen were remarkably high in volcanic ash soils while mineralizable nitrogen ($NH_4$-N and $NO_3$) contents were high in mineral soils. 3. The values of K600, RF and log K were also higher in volcanic ash soils than those in mineral soils, and the absorbance in the visible range were high and color was dark in the soil of which humification was progressed Extracted humic acid from volcanic ash soil was less reactive to the oxidizing chemical reagent and was persistance to the acid or alkali hydrolysises. 4. The major oxygen-containing functional groups in humic substances of volcanic ash soils were phenolic-OH alcoholic-OH and carboxyl groups while those in mineral soil were methoxyl and carbonyl groups. 5. Absorption spectra of alkaline solution of humic acid ranged from 200 nm to maxima 500 nm. Visible spectra peaks of from humic substances in the visible region were recognized at 350, 420, 450 and 480 nm. Only one single absorbance peak was observed in the visible region at 362 nm for Heugag series and two absorbance Peak were also at 360 nm and 390 nm for Yeungrag series. 6. Evolution of carbon as $Co_2$ was increased with addition of Na-pyrophosphate in Namweon and Heugag series, and "priming effects" took place on the soil organic matter decomposition by addition of rice straw with albumin in Ido series.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.464-469
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• 2006

This study was conducted to evaluate a knowledge on food components of muscle and adductor muscle of pearl oyster (Pinctada fucata martensii) as pearl processing byproducts. The concentrations of mercury and chromium as heavy metal were not detected in both pearl oyster muscle and adductor muscle, and those of cadmium and lead were 0.06 ppm and 0.11 ppm in only pearl oyster muscle, respectively. Thus, the heavy metal levels of pearl processing byproducts were below the reported safety limits. The volatile basic nitrogen (VBN) content and pH of pearl oyster muscle were 11.6 mg/100g and 6.31 and those of abductor muscle were 8.6 mg/100 g and 6.33, respectively. It was concluded that pearl oyster muscle and adductor muscle might not invoke health risk in using food resource. The contents of crude protein (16.5%) and total amino acid (15,691 mg/100 g) of adductor muscle were higher than those of muscle (11.2% and 10,131 mg/100 g) and oyster (12.1% and 11,213 mg/100 g) as a control. The contents of calcium and phosphorus were 95.4 mg/100 g and 116.0 mg/100 g in muscle, 75.2 mg/100g and 148.1 mg/100 g in adductor muscle, respectively. The calcium level based on phosphorus was a good ratio for absorbing calcium. The free amino acid contents and taste values were 635.5 mg/100 g and 40.2 in muscle, and 734.9 mg/100 g and 24.1 in adductor muscle, respectively, but that (882.8 mg/100 g and 40.2) of oyster was higher than those of pearl processing byproducts. Based on the results of physicochemical and nutritional properties, pearl oyster muscle and adductor muscle can be utilized as a food resource.

• The Korean Journal of Mycology
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• v.7 no.1
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• pp.13-73
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• 1979

These studies were conducted to investigate nutrient sources and supplementary materials of synthetic compost media for Agaricus bisporus culture. Investigation were carried out to establish the optimum composition for compost of Agaricus bisporus methods of out-door fermentation and peakheating with rice straw as the main substrate of the media. The incidence and flora of harmful organisms in rice straw compost and their control were also studied. 1. When rice straw was used as the main substrate in synthetic compost as a carbon source. yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw, and the total nitrogen content was high in rice straw compost. 2. Since the morphological and physico-chemical nature of Japonica and Indica types of rice straw are greatly dissimilar. there were apparent differences in the process of compost fermentation. Fermentation of Indica type straw proceeded more rapidly with a shortening the compost period, reducing the water supply, and required adding of supplementary materials for producing stable physical conditions. 3. Use of barley straw compost resulted in a smaller crop compared with rice straw. but when a 50%, barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. 4. There were extremely high positive correlations between yield of Agaricus bisporus and the total nitrogen, organic nitrogen, amino acids, amides and amino sugar nitrogen content of compost. The mycerial growth and fruit body formation were severely inhibited by ammonium nitrogen. 5. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. 6. The supplementation of organic nutrient activated compost fermentation and increased yield of Agaricus bisporus. The best sources of organic nutrients were: perilla meal, sesame meal, wheat bran and poultry manure, etc. 7. Soybean meal, tobacco powder and glutamic acid fermentation by-products which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. B. When gypsum and zeolite were added to rice straw. physical deterioration of compost due to excess moisture and caramelization was observed. The Indica type of straw was more remarkable in increase of yield of Agricus bisporus by addition of supplementing materials than Japonica straw. 9. For preparing rice straw compost, the best mixture was prepared by 10% poultry manure, 5% perilla meal, 1. 2 to 1. 5% urea and 1% gypsum. At spring cropping, it was good to add rice bran to accelerate heat generation of the compost heap. 10. There was significantly high positive correlation (r=0.97) between accumulated temperature and the decomposition degree of compost during outdoor composting. The yield was highest at accumulated temperatures between 900 and $1,000^{\circ}C$. 11. Prolonging the composting period brought about an increase in decomposition degree and total nitrogen content, but a decrease in ammonium nitrogen. In the spring the suitable period of composting was 20 to 25 days. and about 15 days in autumn. For those periods, the degree of decomposition was 19 to 24%. 12. Compactness of wet compost at filling caused an increase in the residual ammonium nitrogen. methane and organic acid during peak heating. There was negative correlation between methane content and yield (r=0.76)and the same was true between volatile organic acid and yield (r=0.73). 13. In compost with a moisture content range between 69 to 80% at filling. the higher the moisture content, the lower the yield (r=0.78). This result was attributed to a reduction in the porosity of compost at filling the beds. The optimum porosity for good fermentation was between 41 and 53%. 14. Peak heating of the compost was essential for the prevention of harmful microorganisms and insect pests. and for the removal of excess ammonia. It was necessary to continue fer mentatiion for four days after peak heating. 15. Ten species of fungi which are harmful or competitive to Agaricus bisporus were identified from the rice compost, including Diehliomyces microsporus, Trichoderma sp. and Stysanus stemoites. The frequency of occurrance was notably high with serious damage to Agaricus bisporus. 16. Diehliomyces microsporus could be controlled by temperature adjustment of the growing room and by fumigating the compost and the house with Basamid and Vapam. Trichoderma was prevented by the use of Bavistin and Benomyl. 17. Four species of nematodes and five species of mites occured in compost during out-door composting. These orgnanisms could be controlled through peakheating compost for 6 hours at $60^{\circ}C$.