• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.1-14
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• 1979

The fertility which is the combined factor is one of the important capability determiants of paddy soils. In this study, we aimed at attaining a quantitative evaluation of soil fertility and further establishing an objective fertility classification on the basis of the fertility evaluation. The samples used in this series studies were collected from Korean paddy field. They include deltas, flood plains, coastal plains, valley plains, fans and low terraces. On the basis of correlation analysis, factor analysis was applied to a set of 15 variables. As a result of factor analysis, five mutually independent and clearly definable fertility component factors were extracted from the 15 variables for the whole 90 surface soil samples. The fertility status of each sample soil could be objectively designated by the score of the five factors. As a means of summarizing the information obtained, taxonomic distances between all pairs of the samples were computed from these five factor scores further to be subjected to numerical taxonomy. Seven fertility groups were formulated, each of which was characterized by one or more of the fertility components. As this fertility classification was based on the present state of soil properties, it would be useful in pointing to the proper direction of further fertility amelioration and improvement for each group to enhance potential productivity of Korean paddy fields.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.254-259
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• 1991

The present study was carried out to investigate the effect of nitrogen(urea) application on the seasonal change in pH content of Bray No.1-P, organic matter, and exchangeable cations along the grassland soil profile and further to provide the fundamental information for optimizing the rate of fertilizer application to grassland. Soil samples were taken 20cm intervals upto 100cm soil depth in spring(May 26), summer(July 27), and autumn (October 18) of 1990. The obtained results are summerized as follow 1. In spring and summer, soil pH at 0-20cm soil depth of 28kg N/10a treatment was lowered by 0.7 and 1.0 in comparison with those the same soil depth of 0 kg N/10a treatment and the tendency in pH decrease during all season at the soil depth below 20cm was in the order of summer>spring>autumn. 2. Although Bray No.1-P content at the soil depth 0-20cm of 28kg N/10a treatment was lowered by 20ppm compared to 0 kg N/10a treatment in summer, there was no great difference in its content between 0kg N/10a and 28kg N/10a treatment at all soil depth in spring and summer. In autumn, its content at soil depth below 20cm of 28kg N/10a treatment was higher than that of in summer. 3. Organic matter content at 0-20cm soil depth of 0 and 28kg N/10a treatment in autumn was slightly lowered and on the whole there was very little change in it by soil depth and nitrogen application. 4. The calcium content of 0 and 28kg N/10a treatment was also slightly lowered by increase in soil depth and Mg and K contents were below 0.4 and 0.2 me/100g during all seasons, respectively. 5. Positive correlations were shown among the $NH_4-N$ content and pH, organic matter, Ca and Mg of 0 kg N/10a treatment, however, there was negative correlation ($r=-0.534^{*}$) between $NO_3-N$ content and pH of 28kg N/10a treatment in summer.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.4
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• pp.234-241
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• 2000

Organic farming (OF) is regarded as alternative farming types against general farming system for sustainable agriculture, recently. However, there is little information on effects of OF on soil properties and watershed condition. In order to determine the effects of OF on soil properties, 36, 10 and 8 sites of organic farming (OF) fields of plastic film houses, paddy and orchard were selected in the national scale, respectively, to evaluate their chemical properties and phosphorus distributing characteristics. The average organic matter (OM) contents in organic farming fields were with $44g\;kg^{-1}$ in plastic film houses, $26g\;kg^{-1}$ in paddies and $39g\;kg^{-1}$ in orchard soils higher than the average OM contents in conventional farming (CF) soils. Available phosphates were accumulated to 986 in plastic film house soils and $754mg\;kg^{-1}$ in orchard soils, respectively, over the optimum range. Furthermore, total P (T-P) reached to $2.973mg\;kg^{-1}$ in plastic film houses and $2303mg\;kg^{-1}$ in orchards in OF soils. It could be attained by applying repeatedly low N/P ratio of manure-based compost. In two types of soils inorganic P was dominant with the ratio of 62~80% of T-P, and then residual and organic Ps followed. However. residual-P was dominant in paddy soils with the rate of 50% of T-P. Fractionation of soil extractable P showed that Ca-P was dominant with about $1,330mg\;kg^{-1}$ in upland soils in OF fields, which is affected by high soil pH of over 6.0. However. Fe-P of extractable P was dominant in paddy soils. Water-soluble P was very high with 65 and $26mg\;kg^{-1}$ in plastic film house and orchard soils in OF. From this results. OF regarded as an environment-friendly farming system may cause serious soil deterioration by accumulated phosphorus and may also cause water pollution.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.376-383
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• 2003

To utilize composts more efficiently, combining composts with fertilizer to meet crop requirements is an appealing alternative. A pot experiment was conducted to study the effect of application rate of composted pig manure blended with fertilizer on the availability and loss of fertilizer-N. Chinese cabbage (Brassica campestris L. cv. Samjin) plants were cultivated for 30 and 60 days. 15N-Labeled urea ($5.24\;^{15}N\;atom\;%$) was added to soil at $450mg\;N\;kg^{-1}$, and unlabeled compost ($0.37\;^{15}N\;atom\;%$) was added at 0, 200, 400, and $600mg\;N\;kg^{-1}$. The amount of plant-N derived from urea was not affected by compost application at rate of $200mg\;N\;kg^{-1}$. However, compost application at 400 and $600mg\;N\;kg^{-1}$ significantly (P<0.05) increased plant assimilation of N from urea irrespective of sampling time, probably because of physicochemical changes in the soil properties allowing urea-N to be assimilated more efficiently. The amount of immobilized urea-N increased with increasing rate of compost application at both growth periods, as the results of increased microbial activities using organic C in the compost. Total recovery of urea-N (as percentage of added N) by Chinese cabbage and soil also increased with increasing rate of compost from 71.5 to 95.6% and from 67.0 to 88.2% at the 30- and 60-days of growth, respectively. These results suggest that increasing rate of compost blending increases plant uptake of fertilizer-N and enhances immobilization of fertilizer-N, which leads to decrease in loss of fertilizer-N. However, information about the fate of immobilized N during future crop cultivation is necessary to verify long-term effect of compost blending.

• Weed & Turfgrass Science
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• v.3 no.2
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• pp.71-77
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• 2014

Surveys of weed species in paddy fields were conducted in Korea to identify weed occurrence from June to September 2013. Total 3,434 sites of paddy fields in 155 City/Gun, eight Provinces were investigated. From the nation-wide survey, 90 weed species in 28 families were identified and classified to 52 annuals, 3 biennials and 35 perennials. Based on the occurrence ratio, the most weed species belonged to Poaceae (18 species). 17, 8 and 6 weed species belonged to Cyperaceae, Scrophulariaceae and Polygonaceae, respectively, and these 49 weed species in the most four families accounted for 54% of total weed occurrence. The most dominant weed species in Korean paddy fields were Echinochloa spp. (17.4%), followed by Monochoria vaginalis (12.4%), Eleocharis kuroguwai (7.8%), Bidens tripartite (9.27%), Scirpus juncoides (6.2%) and Sagittaria sagittifolia (6.1%). This information could be useful for estimation of future weed occurrence, weed population dynamics and establishment of weed control methods in paddy fields of Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.3
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• pp.241-258
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• 1998

The experimental demersal trawl surveys to provide the essential information for the assessment, management and utilization of commercially important fish stocks in the southern waters of Korea were carried out during five research cruises between October 1996 and October 1997 by the training ship “KAYA” of Pukyong National University. The biological sampling was conducted by using the trawl net with a cover net of 36 mm in mesh size at 64 planned trawl stations during daylight to identify the biological characteristics of fish. Each catch was standardized into catch per unit of time and the catches at each trawl station were sorted, weighed and counted by species. The changes in catches of each fish species and the shifts in dominant species by seasions and sampling regions in the research area were analyzed, and the abundance of fish was estimated from the relationship between the trawl catches and the volume of the water column sampled by demersal trawls. The results obtained can be summarized as follows : 1. During the 64 demersal trawls conducted in the southern waters of Korea, 129 species including 112 species of fishes, 8 species of Cephalopoda and 7 species of Crustacea, were identified Also, during the 1996 and 1997 trawl surveys in the reseach area, a large number of commercially important species with small differences in proportion was found. me proportion of Japanese horse mackerel which comprised 19.8% of the total catch by weight was highest, followed by chub mackerel(15.0%), swordtip squid(9.0%), redwing searobin(6.2%), konoshiro gizzard shad(6.1%), Japanese flying squid(5.8%), silver pomfet(5.1%), blackmouth goosefish(5.1%), etc. Swordtip squid, Japanese flying squid, blackmouth goosefish and blackthroat seaperch were among the dominant species in all seasons with a relatively high and stab1e proportion(3.6~9.0%), and were widely distributed in the entire southern water of Korea. 2. The catch rates by cover net varied at 0.7~91.9% by weight of the total trawl catch by codend and cover net at 64 planned trawl stations and the mean catch rate was 44.4%. Species comprising a major portion of the catches by cover net mainly were swordtip squid, konoshiro gizzard shad, the juveniles of Japanese horse mackerel, blackthroat seaperch and chub mackerel, etc. 3. The distribution density of fish in terms of biomass per unit volume which derived from the catch data by 63 bottom trawl hauls in the southern waters of Korea ranged from 17.9 $\times$ 10-6 to 1,440.9 $\times$ 10-6kg/m3 with the mean value of 153.8 $\times$ 10-6 kg/m3. These fish densities varied between seasons, location of sampling stations and sea conditions. From these results, it is worth noting that the catch composition of multispecies and the increased occurrence of small fish in the southern waters of Korea may also result in new problems in determining the total allowable catch(TAC) levels for economically important species.

• The Korean Journal of Food And Nutrition
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• v.19 no.2
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• pp.183-192
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• 2006

The purpose of this study was to investigate the performance of elementary school dietitians in terms of nutrition education in the northern portion of Gyeonggi province. Self-administered questionnaires were given to 50 dietitians who have worked in elementary schools with self-operation food service, and 35(70%) dietitians returned the questionnaires. The results are summarized as follows: no students took part in nutrition education as a regular course, but all dietitians performed nutrition education in passive ways, such as 'using home correspondence'(39.0%), 'bulletin board/poster'(22.0%), 'using the internet'(13.4%) and 'indirectly through a classroom teacher'(12.2%). Most respondents performed nutrition education 'one time/month'(66.0%) or 'one time/week'(20.0%). The respondents thought that suitable teaching times for nutrition education were 'during a related subject'(35.5%), 'during lunch time'(22.6%) rather than 'during an independent subject'(16.1%). Most of the dietitians(94.3%) did not perform nutrition counseling because of 'a lack of opportunity'(72.7%) and 'workload'(27.3%). Additionally 88.6% of respondents did not have the time of for nutrition counseling for parents because 'am not a teacher'(56.7%) and 'workload'(30,0%). Information sources for nutrition education were mainly 'internet'(71.4%) and 're-educationa1 materials'(17.1%). They possessed instructional materials in the forms of 'printed materials'(35.1 %), 'exhibition/bulletin board'(31.2%), and 'electrical materials'(33.8%), 'but did not have 'solid materials' such as food models and dolls. Generally they had mostly 'leaflets'(82.9%), 'bulletins'(68.6%), 'internet'(57.1%), and 'CDs'(57.1%). Preferences for instructional materials used were 'printed materials'(46.2%), 'exhibition/bulletin board'(36.5%), and 'electrical materials'(17.3%) 'Leaflets'(80.0%) were mainly used; 'CD'(17.1 %) use was low compared to the proportion possessing CDs. The topics frequently chosen by the subjects for nutrition education were 'table manners'(82.9%), 'basic concepts of food and nutrition'(80.0%), and 'proper food habits'(80.0%), but the topics helpful for practical use, such as 'how much do I eat'(20.0%) and 'nutrition labeling'(37.1%), were not included frequently. The respondents thought that 'eating only what they like'(60.0 %), 'intake of processed foods'(17.8%), and 'obesity'(17.8%) were the most common nutritional problems among elementary school children. They also thought that establishing a regular course for nutrition education was an effective way to cut down on these nutritional problems. In conclusion, nutrition education programs that are combined with effective instructional materials and practical topics should be developed. Additionally, it is recommended that dietitians act as teachers who participate in regular courses as soon as possible.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.132-141
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• 2012

This current survey was conducted to examine consumer attitudes toward factors determining beef purchasing and improving distribution systems. The frequency of beef purchasing was shown to reflect social and economic status, where inhabitants in large cities, such as Seoul, with higher salaries showed a higher frequency. In addition, consumers that were in their forties bought beef more frequently than consumers that were in their twenties. Consumers in Seoul and the megalopolis with a monthly income of higher than 200 million won preferred to purchase meat from department stores and discount markets. In contrast, people in small cities with lower incomes tended to buy meat from butcher shops and brand shops. In a question regarding unsatisfaction factors of retail beef, individuals that were in their thirties with a high income had concerns associated with packaging problems. For people under thirty with low income, the consistency of quality and price were the prime concerns. In regards to the beef grading system, consumer response varied between inhabitants, monthly income and age group, where consumers from small cities that were in their twenties and forties with a low income had a negative viewpoint. For the differential beef distribution system, housewives between the ages of 30 and 40 from a small city with an income higher than 200 million won had a positive response; however, a large number of consumers were not familiar with this system. The most demanding beef cuts were in the following order: loin, flank and rib. In addition, the most important factors determining purchasing beef were as follows: price, breed and portion.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.648-660
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• 1997

The study was conducted to investigate children's attitudes toward food advertisement on children's television programs. A total of 868 subjects were selected from two KangNam and KangBook elementary schools (4, 5, 6th graders). First, it was reviewed food ads. On children's television program on 3 channels between 5∼7 pm from April to July in 1997. Among the total television commercials, 58% were food product ads.. Among the advertised food, the largest number of ads. was for beverages (21.6%) and the next was for cookies (19.7%), followes by sharbet and ice cream (19.5%), fast food (12.4%), cereal (5.5%) and milk and milk products (2.9%). This review revealed that the mostly advertised food are high in calorie, fat and sugar. Secondly, it was conducted a survey. The results of the survey were as follows: weekly average TV watching hours per child: 13.5. 50.8% of the children watched children's program on TV. 83.9% of the subjcts answered that they get their information about new food through TV ads.. 59.2% of children tried to buy the food advertised on TV program. The relationship between TV food ads. and health, 49.4% of the children answered that advertised food were not good for one's health. When we asked them to choose between advertised and non-advertised food, they preferred the advertised ones, such as cookies, beverages, fast food restaurants and cereals (p＜0.001). The results of this study suggest that children's purchasing and selecting of food were influenced by TV food advertisement. Therefore, education is needed which will help children's make responsible, informed consumers choices.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.850-856
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• 2013

This study was conducted to determine the effects of physical treatments for quality of wet noodles. Noodles were being tried with a microwave (for 1 min), an autoclave (for 30 or 50 min), and both autoclave and microwave (for 30/1 min or 50/1 min). The results showed that the pH levels were slightly decreased after treatments of autoclave and autoclave/microwave. The moisture contents were considerably decreased as compared to the control except autoclave (50 min). After all treatments, the lightness was decreased in all samples, but, redness was increased (except microwave) and the yellowness was increased after autoclave (50 min) and autoclave/microwave (50/1 min). Texture was increased as compared to the control except microwave. In the sensory evaluation, the noodles treated with microwave, autoclave (50 min), and autoclave/ microwave (50/1 min) showed a high score in overall preference. From these results, both the autoclave and microwave methods can be applied to the wet noodles without diminishing its quality to a great extent.