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A Practical Method to Quantify Very Low Fluxes of Nitrous Oxide from a Rice Paddy (벼논에서 미량 아산화질소 플럭스의 정량을 위한 실용적 방법)

  • Okjung, Ju;Namgoo, Kang;Hoseup, Soh;Jung-Soo, Park
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.285-294
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    • 2022
  • In order to accurately calculate greenhouse gas emissions in the agricultural field, Korea has been developing national-specific emission factors through direct measurement of gas fluxes using the closed-chamber method. In the rice paddy, only national-specific emission factors for methane (CH4) have been developed. It is thus necessary to develop those for nitrous oxide (N2O) affected by the application of nitrogen fertilizer. However, since the concentration of N2O emission from rice cultivation is very low, the QA/QC methods such as method detection and practical quantification limits are important. In this study, N2O emission from a rice paddy was evaluated affected by the amount of nitrogen fertilizer, by taking into account both method detection and practical quantification limits for N2O concentration. The N2O emission from a rice paddy soils affected by the nitrogen fertilizer application was estimated in the following order. The method detection limit (MDL) of N2O concentration was calculated at 95% confidence level based on the pooled standard deviation of concentration data sets using a standard gas with 98 nmol mol-1 N2O 10 times for 3 days. The practical quantification limit (PQL) of the N2O concentration is estimated by multiplying 10 to the pooled standard deviation. For the N2O flux data measured during the rice cultivation period in 2021, the MDL and PQL of N2O concentration were 18 nmol mol-1 and 87 nmol mol-1, respectively. The measured values above the PQL were merely about 12% of the total data. The cumulative N2O emission estimated based on the MDL and PQL was higher than the cumulative emission without nitrogen fertilizer application. This research would contribute to improving the reliability in quantification of the N2O flux data for accurate estimates of greenhouse gas emissions and uncertainties.

Comparison of Property Changes of Black Jujube and Zizyphus jujube Extracts during Lactic Acid Fermentation (흑대추와 일반 건조대추의 추출 및 유산발효과정 중 특성 변화)

  • Auh, Mi Sun;Kim, Yi Seul;Ahn, Seung Joon;Ahn, Jun Bae;Kim, Kwang Yup
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.10
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    • pp.1346-1355
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    • 2012
  • This study was carried out to investigate the characteristics of black jujube and Zizyphus jujube extracts during lactic acid fermentation. Both extracts were fermented using Lactobacillus fermentum YL-3. As a result, viable cell number rapidly increased until 24 hours, after which it gradually decreased. Before lactic acid fermentation, the $IC_{50}$ of black jujube, which was 0.014 mg/mL, was lower than that of Zizyphus jujube. Further, black jujube showed stronger antioxidant activity (374.21 mg AA eq/g) than Zizyphus jujube. Contents of total polyphenolics in both extracts were 15.46 mg/g and 13.61 mg/g, respectively, whereas contents of total flavonoids were 374.21 ${\mu}g/g$ and 64.25 ${\mu}g/g$. After lactic acid fermentation, there was no significant increase in DPPH or ABTS free radical scavenging activity. Total polyphenolic content of Zizyphus jujube decreased to 12.39 mg/g upon fermentation, whereas flavonoid content significantly increased to 291.58 ${\mu}g/g$. Further, polyphenolic and flavonoid contents of black jujube increased from 15.46 mg/g to 17.46 mg/g and from 374.21 ${\mu}g/g$ to 1,135.29 ${\mu}g/g$, respectively. These results demonstrate that 9-Times Steamed and Dried increased functional components. Especially, lactic acid fermented black jujube showed remarkably high antioxidant activity. These results confirm the potential use of lactic acid fermented black jujube as a valuable resource for the development of functional foods.

A survey on the nutrient intake and food consumption of the students at the dormitories, College of Agriculture, Seoul National University (서울대학교(大學校) 농과대학(農科大學) 남녀(男女) 기숙사생(寄宿舍生)의 영양섭취(營養攝取) 조사(調査))

  • Mo, Su-Mi;Han, In-Kyu;Kim, Ze-Uook;Lee, Chun-Yung;Kim, Ho-Sik
    • Applied Biological Chemistry
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    • v.7
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    • pp.92-104
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    • 1966
  • For the purpose of the better dietary management and to empahsize of importance in nutrition education for 552 students at the dormitories, College of Agriculture, Seoul National University, the dietary survey was conducted for each consecutive seven days, from March 7th to 13th at the boy's dormitory, from March 14th to 20th at the girl's dormitory, respectively. In comparison the average caloric and nutrient intake per caput per day at the both, girl's and boy's dormitory with the recommended dietary allowances for age of 25, the intake of calories and all nutrients except riboflavin were over the allowances for the boy, while the caloric intake by the girl was considerablly below the allowance. But it is meant that only 150 calories was actually deficient in comparison with the figure of the average energy consumption determined for the girls at the dormitory of the Sook-myung Woman's University, whose pattern of living was quite similar to those of the girls at this college. Except iron and ascorbic acid, all other nutrients were deficient for the girls. The calories in the form of protein of a diet taken by the boy was 12.9% and that by the girl was 12.8%. Protein quality of the diet taken by boy scored 70 while that by the girl scored 79. NDp Cal% of the diet taken by the boy was 7 and that by the girl was figured out to be 8. Therefore, calculated reference protein taken by the boy was 55.8 grams and that by the girl was 36.9%. Though it is generally recommended that at least 1/3 of the protein should come from animal sources, it was apparent by this survey that providing 1/5 of the protein from animal sources with remaining part of high quality vegetable protein foods in the adequate mixed diet would give satisfactory results for both girl and boy students. This was clearly demonstrated by the recommended reference protein and NDp Cal% met. Significant difference between boys and girls in the average consumption of seasonings was found. In consumption per day of seasonings, boy used 1.5 grams of red pepper powder which means they used 15 times more of red pepper than girls did. Kochujang was used 13 grams by boy-students which was as high as 21 times of that of the girl. Total salt intake by the boy was 34 grams while the girl consummed 23 grams. It is obviously recognized that boys prefer more peppery and salty flavor than girls do. To reduce the amount of protein consummed and to improve the quality of protein food, increase of riboflavin rich food and increase of fat intake in place of grain intake are recommendable to the boy. For the girl's diet, consumption of grains, particularly more intake of barley mal· be recommendable to meet the B group of vitamins allowances as well as the caloric allowance. The use of more servings of yellow green vegetables is needed to the girl.

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Consumer Awareness and Evaluation of Retailers' Social Responsibility: An Exploratory Approach into Ethical Purchase Behavior from a U.S Perspective (소비자인지도화령수상사회책임(消费者认知度和零售商社会责任): 종미국시각출발적도덕구매행위적탐색성연구(从美国视角出发的道德购买行为的探索性研究))

  • Lee, Min-Young;Jackson, Vanessa P.
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.1
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    • pp.49-58
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    • 2010
  • Corporate social responsibility has become a very important issue for researchers (Greenfield, 2004; Maignan & Ralston, 2002; McWilliams et al., 2006; Pearce & Doh 2005), and many consider it necessary for businesses to define their role in society and apply social and ethical standards to their businesses (Lichtenstein et al., 2004). As a result, a significant number of retailers have adopted CSR as a strategic tool to promote their businesses. To this end, this study sought to discover U.S. consumers' attitudes and behavior in ethical purchasing and consumption based on their subjective perception and evaluation of a retailer. The objectives of this study include: 1) determine the participants awareness of retailers corporate social responsibility; 2) assess how participants evaluate retailers corporate social responsibility; 3) examine whether participants evaluation process of retailers CSR influence their attitude toward the retailer; and 4) assess if participants attitude toward the retailers CSR influence their purchase behavior. This study does not focus on actual retailers' CSR performance because a consumer's decision making process is based on an individual assessment not an actual fact. This study examines US college students' awareness and evaluations of retailers' corporate social responsibility (CSR). Fifty six college students at a major Southeastern university participated in the study. The age of the participants ranged from 18 to 26 years old. Content analysis was conducted with open coding and focused coding. Over 100 single-spaced pages of written responses were collected and analyzed. Two steps of coding (i.e., open coding and focused coding) were conducted (Esterberg, 2002). Coding results and analytic memos were used to understand participants' awareness of CSR and their ethical purchasing behavior supported through the selection and inclusion of direct quotes that were extracted from the written responses. Names used here are pseudonyms to protect confidentiality of participants. Participants were asked to write about retailers, their aware-ness of CSR issues, and to evaluate a retailer's CSR performance. A majority (n = 28) of respondents indicated their awareness of CSR but have not felt the need to act on this issue. Few (n=8) indicated that they are aware of this issue but not greatly concerned. Findings suggest that when college students evaluate retailers' CSR performance, they use three dimensions of CSR: employee support, community support, and environmental support. Employee treatment and support were found as an important criterion in evaluation of retailers' CSR. Respondents indicated that their good experience with a retailer as an employee made them have a positive perception and attitude toward the retailer. Regarding employee support four themes emerged: employee rewards and incentives based on performance, working environment, employee education and training program, and employee and family discounts. Well organized rewards and incentives were mentioned as an important attribute. The factors related to the working environment included: how well retailers follow the rules related to working hours, lunch time and breaks was also one of the most mentioned attributes. Regarding community support, three themes emerged: contributing a percentage of sales to the local community, financial contribution to charity organizations, and events for community support. Regarding environments, two themes emerged: recycling and selling organic or green products. It was mentioned in the responses that retailers are trying to do what they can to be environmentally friendly. One respondent mentioned that the company is creating stores that have an environmentally friendly design. Information about what the company does to help the environment can easily be found on the company’s website as well. Respondents have also noticed that the stores are starting to offer products that are organic and environmentally friendly. A retailer was also mentioned by a respondent in this category in reference to how the company uses eco-friendly cups and how they are helping to rebuild homes in New Orleans. The respondents noticed that a retailer offers reusable bags for their consumers to purchase. One respondent stated that a retailer uses its products to help the environment, through offering organic cotton. After thorough analysis of responses, we found that a participant's evaluation of a retailers' CSR influenced their attitudes towards retailers. However, there was a significant gap between attitudes and purchasing behavior. Although the participants had positive attitudes toward retailers CSR, the lack of funds and time influenced their purchase behavior. Overall, half (n=28) of the respondents mentioned that CSR performance affects their purchasing decisions making when shopping. Findings from this study provide support for retailers to consider their corporate social responsibility when developing their image with the consumer. This study implied that consumers evaluate retailers based on employee, community and environmental support. The evaluation, attitude and purchase behavior of consumers seem to be intertwined. That is, evaluation is based on the knowledge the consumer has of the retailers CSR. That knowledge may influence their attitude toward the retailer and thus influence their purchase behavior. Participants also indicated that having CSR makes them think highly of the retailer, but it does not influence their purchase behavior. Price and convenience seem to surpass the importance of CSR among the participants. Implications, recommendations for future research, and limitations of the study are also discussed.

Physicochemical Characteristics and Biological Activities of Rice and Amaranth Fermented by Bacillus subtilis KMKW4 (Bacillus subtilis KMKW4를 이용한 백미 및 아마란스 발효물의 이화학적 특성 및 생리활성)

  • Yang, Su-Jin;Lee, Rea-Hyun;Hong, Joo-Heon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.4
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    • pp.540-548
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    • 2015
  • This study examined the cultural characteristics and biological activities of fermented rice and amaranth with Bacillus subtilis KMKW4. These samples were made with various amounts of rice and amaranth [100:0 (R100), 90:10 (R90), 80:20 (R80), and 70:30 (R70)]. B. subtilis KMKW4 was used as starter for the fermentation, and its cultures at the lated logarithmic growth were inoculated for final concentration of 2% (v/v). Number of viable cells of fermented R80 (7.67 log CFU/mL) was greater than those of R100, R90, and R70 (7.48 log CFU/mL, 7.38 log CFU/mL, and 7.09 CFU/mL, respectively) during the fermentation period (120 h). Amylase activities of fermented R80 and R100 were 57.77 U/mL and 19.91 U/mL, respectively. Furthermore, amylase activities of fermented freeze-dried powders of R100 and R80 were 24.31 U/g and 9.12 U/g, respectively. Free sugar contents of R100 and R80 increased after fermentation, and that of R80 (5,454.15 mg/100 g) significantly increased compared to that of R100 (4,274.85 mg/100 g). The free amino acid content of R80 was higher than that of R100. DPPH and superoxide radical scavenging activities of 5 mg/mL of fermented freeze-dried powder (R80) were 44.21% and 89.76%, respectively. ACE inhibition rates and ${\alpha}$-glucosidase inhibitory activities were significantly higher in R80 than R100. This study suggested that fermentation of R80 might be a new potential source of antioxidant, anti-diabetic, and anti-hypertensive agents applicable to grain enzyme-containing foods.

THE EFFECTS OF EXTRACTIONS IN FACIAL VERTICAL CHANGES (발치가 안모의 수직변화에 미치는 영향)

  • Ma, Joon;Yoon, Young-Jooh;Kim, Kwang-Won
    • The korean journal of orthodontics
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    • v.27 no.6 s.65
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    • pp.905-916
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    • 1997
  • The purpose of this investigation were to evaluate facial vortical changes occurring in patients treated orthodontically with first premolar, second remolar and second molar extractions : to compare these changes with those occurring in patients treated orthodontically without extractions : and finally, to evaluate the effects of extractions in facial vortical changes. Cephalometric records of 50 male & female nonextraction patients and 88 male & female extraction patients were obtained from the department of orthodontics at Chosun University, College of Dentistry. The second molar fully erupted pPatients to have little variation according to growth were chosen as the sample for this investigation. For comparisons, the samples of 88 male & female extraction patients were subdivided into 42 first premolar extraction, 24 second premolar extraction, and 22 second molar extraction patients. Fourteen cephalometric measurements were selected to examine whether orthodontic extraction treatment led to vertical changes or not. The pretreatment and posttreatment lateral cephalographs were taken on the same radiographic unit. $SPSS/PC^+$ statistical program was used to compare and to analyze the changes between 'before & after' orthodontic treatment. The results of this study were as follows. 1. There were no statistical significances in any cephalometric measurements between 'before & after' orthodontic treatment regardless of orthodontic extractions for each group. 2. On average, the upper 6 to palatal Plane and the lower 6 to mandibular plane after orthodontic treatment were increased in all group. This means most of orthodontic mechanics are extrusive in nature. Especially, in orthodontic extraction. cases, it may be caused by orthodontic mechanics for space closure and alignments. 3. On average, in the second molar extraction group, the facial vertical dimension was increased after orthodontic treatment. It nay be induced as a result of moving the molars distally to gain enough space to correct the molar relationship and to simultaneously improve the deep bite. 4. There was no statistical significance between orthodontic extractions and facial vertical changes. This means that orthodontic extractions have no influence on facial vortical changes. 5. The cephalometric measurements with statistical significance in ficial vertical changes for each group were PP-MP, Op-MP, $\underline{1}$ to PP and $\overline{1}$ to MP.

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A Study of Serum Cytokines in the Patients with Chronic Hepatitis B Virus Infection (만성 B형 간염 바이러스 감염 환자에서 혈청 Cytokine에 관한 연구)

  • Kim, Byung-Ju;Ma, Jae-Sook;Hwang, Tai-Ju
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.1 no.1
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    • pp.90-99
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    • 1998
  • Purpose: The aim of this study was to clarify the serum cytokine pattern in patients with chronic HBV infection in terms of their clinical state. Methods: Intravenous blood samples were taken from 35 patients who were seropositive for HBsAg for at least 6 months and 7 healthy controls. Samples were initially tested for serum aminotransferases and serologic markers for hepatitis B virus by EIA. Serum levels of interleukin(IL)-2, tumor necrosis factor-alpha (TNF-${\alpha}$), interferon-gamma (IFN-${\gamma}$), IL-4, and IL-10 were measured by ELISA. Results: Among 35 patients, seropositive for HBeAg was 20 and for anti-HBe was 15. The histologic diagnosis of 19 patients underwent liver biopsy were chronic persistent hepatitis (CPH) in 10 and chronic active hepatitis (CAH) in 9. Serum IL-10 level in patients seropositive for HBeAg was significantly higher than that in patients seropositive for anti-HBe (p<0.05). All measured cytokine levels in patients with CAH were higher than those of patients with CPH. High values of all measured cytokines except IL-4 were seen in patients with AST and ALT > 100 U/L. High level of IL-4 was seen in patients with normal aminotransferase levels. Conclusion: These results were thought to indicate that anti-inflammatory Th2-like cytokine (IL-10) production in chronic HBV infection is related to circulating HBeAg rather than activity of hepatitis and that Th1 cytokines seem to be associated with the increasing activity of hepatitis.

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The Change of Health Status through the Intervention of Community Health Center based Physical Activity and Exercise Program (신체활동 및 운동 중재 프로그램에 의한 건강상태의 변화)

  • Kim, Eun-Young;Lee, Tae-Yong;Lee, Moo-Sik
    • Journal of agricultural medicine and community health
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    • v.29 no.1
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    • pp.77-89
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    • 2004
  • Objectives: This study was conducted to investigate the change of health status through the intervention of physical activity arid exercise program for the people living in the area where health promotion program has been executed. Methods: The data was obtained from self--administered questionnaire. The questionnaire consisted of general characteristics, physical activity transition and health status variables using the SF-36(36-Item Short-From Health Survey). Data were analyzed 134 subjects participating in the physical activity arid exercise intervention programs. Results: The 35.1% of adults above 20 years of age are regularly physical activity and exercise before intervention program. but the rate increased to 49.3% after that. Frequency and duration of physical activity were increased, and frequency of participating in physical activity was increased from 0.9 times a week to 2.1 times especially. Scores of health status measured by SF-36 was increased in category (if general health after intervention of program, but those were decreased in category of vitality and mental health. Physical function of four groups classified by change of behavioral pattern were increased after intervention of program, especially in groups starting to physical activity. Conclusions: Physical activity and exercise is associated with health status. This study suggest that effective strategy and policy supporting for the promotion of physical activity and exercise should be needed in all peoples.

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Mineralogy and Genesis of Hydrothermal Deposits in the Southeastern Part of Korean Peninsula : (5) Deogbong Napseok Deposit (우리나라 동남부 지역의 열수광상에 대한 광물학적 및 광상학적 연구:(5) 덕봉납석광상)

  • Kim, Soo-Jin;Choo, Chang-Oh;Kim, Won-Sa
    • Journal of the Mineralogical Society of Korea
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    • v.7 no.1
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    • pp.25-39
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    • 1994
  • The Deogbong napseok clay deposit which is composed mainly of dickite and pyrophyllite has been formed by hydrothermal alteration of the Late Cretaceous volcanic rocks consisting of andesitic tuff and andesite. The mineralogy of the napseok ores and the hydrothermal alteration processes have been studied in order to know the nature of the interaction between minerals and fluids for the formation of the deposit. Chemical distribution shows that alkali elements and silica were mobile but alumina was relatively immobile during the hydrothermal processes. It is evident that enrichment of alumina and leaching of silica from the host rock led to the formation of the napseok ore, whereas the enrichment of silica in the outer zone of the deposit gave rise to the silica zone. A large amount of microcrystalline quartz closely associated with dickite and pyrophyllite suggests the increasing activity of silica. Thus Si which was released away from the argillic zone by the increasing activity of silica. Thus Si which was released away from the argillic zone by the increasing activity of silica solubility moved out precipitating in the margin of the deposit to form the silica zone. Variation in dickite crystallinity implies the local change in the stability of the system. Thermodynamic calculation shows that the invariant point of pyrophyllite-dickite (kaolinite)-diaspore-quartz assemblages at 500 bars in the system $Al_{2}O_{3}-SiO_{2}-H_{2}O$ is about 300 $^{\circ}C$. Based on the mineral assemblages and the experimental data reported, it is estimated that the main episode of hydrothermal alteration occurred at least above 270 to 300 $^{\circ}C$ and $X_{CO_2}$ <0.025. Mineral occurrence and chemical variation indicate that the activity of Al is high in the upper part of the deposit, whereas the activity of Si is high in the lower part and the margin of the deposit. The nonequilibrium phase relations observed in the Deogbong deposit might be due to local change in intensive thermodynamic variables and fluid transport properties that resulted in the formation of nonequilibrium phases b of several stages.

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Influence of Soil Texture and Bulk Density on Root Growth Characteristics and Nutrient Influx Rate of Soybean Plant (토성(土性)과 용적밀도(容積密度)가 대두(大豆)의 뿌리 생장특성(生長特性)과 양분흡수기능(養分吸收機能)에 미치는 영향(影響))

  • Jung, Yeong-Sang;Lim, Hyung-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.22 no.3
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    • pp.221-227
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    • 1989
  • This study was conducted to understand the influence of soil compaction on root growth and nutrient uptake characteristics of the soybean roots grown in two soils with different texture. Tap root elongation was measured on young seedling grown in cores compacted to different bulk densities of 1.2, 1.4 and $1.6/cm^3$ with different soil water retention in laboratory. The soil used were Samgag sandy loam and Baegsan loam soils. The wet and dry weight, total length, average radius and total surface area of roots were measured on soybean plants grown in 1/5000 a Wagner pots compacted to different bulk density of 1.2 and $1.4g/cm^3$. The nutrient uptake of soybean shoot was measured and evaluated with the unit surface area of roots at the 7th, 17th and 27th days after germination. The results were as follows: 1. The tap root elongation rate was faster in the loam soil with low bulk density than in the sandy loam soil with high bulk density. The elongation rates were remarkedly decreased when soil water was lower than the retention of 4 bars in loam soil and that of 1 bars in sandy loam soil. 2. Tap root elongation rate sharply decreased as increased soil strength higher than $2kgf/cm^2$ measured by ELE penetrometer showing curvillinear regression. However, it was low regardless of soil strength when soil water retention was 10 bars in sandy loam soil. 3. From the pot experiment, the total length of roots were longer in loam soil than in sandy loam soil and was longer in the soils with lower bulk density. The average radius of fine roots grown in sandy loam soil was larger than that grown in loam soil. The total surface area of roots was greater in the loam soil with low bulk density than in the sandy loam soil with high bulk density as the total length of roots. 4. The amounts of nutrient uptake by soybean shoots were greater in loam soil primarily due to more production of dry matter than in sandy loam soil. The nitrogen influx rates through the unit surface area were 597 to $753nmoles/day-cm^2$ in loam soil and 222 to $365nmoles/day\;cm^2$ in sandy loam soilshowing higher value in higher bulk density. The potasium influx rates were 99 to $175nmoles/day-cm^2$, and those of phosphate were 26 to $46nmoles/day\;cm^2$. Those of Ca and Mg were 175 to 246 and 163 to $205nmoles/day\;cm^2$. The difference in nutrient influx rates between bulk densities of these elements were lower than that of nitrogen.

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