• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.387-393
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• 2001

To use as a fundamental data for the sustainable agriculture, which is nowadays a major trend to keep the productivity and conserve the environment, 487 paddy soil samples were collected from 21 regions of the Gyeongnam Province and analyzed the chemical characteristics and microbial population of the soil. The microbial population densities were bacteria $298{\times}10^5$($4{\sim}3000{\times}10^5$ range), fungi $63{\times}10^3$($2{\sim}441{\times}10^3$ range), actinomycetes $19{\times}10^5$($0.2{\sim}1250{\times}10^5$ range), Bacillus sp. $53{\times}10^4$($4{\sim}890{\times}10^4$ range) and Pseudomonas sp. $198{\times}10^4CFU\;g^{-1}$($4{\sim}1724{\times}10^4CFU\;g^{-1}$ range), respectively. The microbial populations of the soil were in general higher in southern area than in the northern area of the Gyeongnam Province. The average ratio of bacteria/fungi population was 473. As soil clay content increased, the populations of aerobic bacteria, actinomycetes and Pseudomonas sp. were remarkably decreased. The ratio of aerobic bacteria and fungi was 1554 in sandy loam and clay loam 1144, while Bacillus sp./fungi ratio was 11 in clay loam and 10 in loam. On the topographical differences, aerobic bacteria and Bacillus sp./fungi ratio were the higher in coastal plains than any other areas. The microbial population densities from different soil types were generally lower in ill-drained paddy field than those of other paddy field. The content of $P_2O_5$, K, Ca, $NO_3-N$ and EC in soil were positively correlated to the population densities of aerobic bacteria, actinomycetes, fungi, Bacillus sp. and Pseudomonas sp.. The soil organic matter and Mg content were also positively correlated to the population densities of aerobic bacteria, actinomycetes, fungi and Bacillus sp.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.2
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• pp.118-126
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• 2002

To evaluate the correlations of microbial populations with soil healthiness and crop production and establish the criteria for microbial population of soil types. We analyzed the microbial community structure of 13 soils which were different in physical and chemical properties and cultivation methods. According to the analysis of microbial population suing the dilution plate method, the large differences of the microbial population structures among soil types were shown: aerobic bacteria $2-27{\times}10^6$, fluorescent Pseudomonas $1-1,364{\times}10^5$, Gram negative bacteria $1-126{\times}10^4$, and mesophilic Bacillus $1-110{\times}10^5$. The density of Gram negative bacteria was highest on red pepper cultivating soils (sample no. 4 and 6) of Umsung and Gesan, Chungbuk, and the density of the fluorescent Pseudomonas was highest on greenhouse soil (sample no. 7) of Jinju, Kyungnam. The crop productivity of three soils was high as compared with those of other soils. It was supposed that the density of fluorescent Pseudomonas and mesophilic Bacillus were correlated with the incresed crop production. By MIDI analysis, 579 strains isolated from 13 soils composed of a variety of microbes including 102 isolates of Agrobacterium, 112 isolates of Bacillus, 32 isolates of Pseudomonas, 44 isolates of Kocuria, and 34 isolates of Pseudomonas. Among the 624 isolates of Gram negative bacteria, Pseudomonas including P. putida and p. fluorescens occupied the highest density (51%), and Stenotrophomonas maltophilia and Burkholderia cepacia also appeared at high density. From RAPD analysis, the fluorescent Pseudomonas strains isolated from 13 soil types showed a high level of strain diversities and were grouped into 2 - 14 patterns according to soil types. Many of unknown bacteria were recovered from the paddy soil, and needed to be further characterized on the molecular basis.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.551-558
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• 2003

This study was conducted to investigate the effect of dietary wormwood powder (Artemisia montana Pampan; WP) supplementation on growing performance and fecal noxious gas emission in weanling pigs. One hundred and twelve pigs were alloted into four treatments and offered for 4 weeks one of the diets supplemented with 0% (control), 0.5% (0.5), 1.0% (1.0) and 2.0% (2.0) WP. Each treatments has four replicate with 7 pigs per replicate. ADG, ADFI and F/G were improved by 1.0 and 2.0 WP supplementation during 0d${\sim}$14d feeding. Feed intake of 1.0 WP diet was higher (P<0.05) than any other diet during 15d${\sim}$28d feeding. But there were no differences among the other treatments in the weight gain and feed conversion. During the whole feeding period, daily weight gain and feed intake of pigs fed 1.0 and 2.0 treatments were higher than those of pigs fed control and 0.5 diet. DM digestibility was significantly (P<0.05) higher in weanling pigs fed 0.5, 1.0 and 2.0 WP than that of the control. The protein digestibility was significantly improved in 1.0 WP treatment and the phosphorus digestibility was improved in 2.0 WP treatment. Excretion of nitrogen and phosphorus was significantly (P<0.05) decreased by 2.0 treatment than control. Emission of fecal ammonia after 48 hours storage in vinyl bag dramatically decreased by all the treatments except control. However, there was no statistical difference in fecal hydrogen sulfide emission among treatments. In conclusion, this study suggested that the dietary 1.0${\sim}$2.0 supplementation of WP can improve productivity of pigs decrease fecal $NH_3$ and $H_2S$ gas emission.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.289-296
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• 2002

A broiler experiment was conducted to investigate the effect of supplementing yeast culture (Saccharomyces cerevisiae, Pichia pastoris) on the growth performance, small intestinal microflora and immune response in broiler chickens. One thousand hatched broiler chickens(Ross$^{(R)}$) were assigned to 6 treatments: control (basal diet), CTC; chlorotetracycline 100ppm, YC-SC; yeast culture(Saccharomyces cerevisiae) 0.3%, YC-PP; yeast culture(Pichia pastoris) 0.3%, RPPC-0.1; refined Pichia pastoris culture 0.1%, RPPC-0.3; refined Pichia pastoris culture 0.3%. There were no significant differences in growth, feed intake, feed efficiency and mortality among the treatments. However, chickens fed diets with yeast cultures showed numerically higher weight gain than those fed the control diets. Supplementation of yeast cultures and CTC improved feed efficiency and decreased mortality compared to control. Nutrient digestibilities were not affected by the dietary treatments. Total number of Lactobacilli in small intestine was higher while that of Cl. perfringens was lower with yeast culture treatments than control. Small intestine E. coli population of RPPC-0.3 treatment was significantly lower than that of the control. The serum IgG concentration tended to be higher in broilers fed yeast cultures than those fed the control and CTC diet. In conclusion, the supplementation of yeast culture products showed, although not significant but, numerical advantages in productivity and profile of microbial flora and serum IgG compared to the control and CTC supplementation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.259-266
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• 1998

A study on the biological and chemical characteristics in the middle last Sea of Korea was carried out at 31 stations in October $11\~18$, 1995 on board the R/V Tam-Yang. The chlorophyll a concentration, new and regenerated production, and the vertical diffusion of nitrate from the thermocline structure were investigated. From the vertical distribution of chlorophyll a, subsurface maxima were observed near the thermorline at most stations including the frontal zone, except at the southern stations where the maximum chloropyll a concentration occurred at the surface, The nanophytoplankton was the most dominant fraction comprising $83.5\%$ of total phytoplankton cell numbers, but netphytoplankton were common at the southern stations where the dominant species were Rhizosolenia sp. Nitrogenous new production and regenerated productions were measured using the stable isotope $^{15}N$ nitrate and ammonia uptake method. The vertically integrated nitrogen production varied between 8.470 and $72.945\;mg\;N\;m^{-2}\;d^{-1}$. The f-ratio, which is the traction of new production from primary production, waried between 0.03 and 0.72, indicating that $3\%$ to $72\%$ of primary production was supported by the input of nutrients from below the euphotic zone and the rest are supported by ammonia recycled within the euphotic layer. This range of f-ratio encompasses from extremely oligotrophic to eutrophic area characteristics. The differences in productivity and f-ratio among stations were related to frontal structure and the bottom topography. The values were high near the frontal zone and low outside of it, and the station near Ulleng Island showed the highest f-ratio. Vertical diffusion coefficients were calculated from both the water column stability (Kz-1) of King and Devol's equation (1979) and new nitrogen requirement (Kz-2). The values of Kz-2 ($0.11\~0.55\;cm^2/s$) were relatively low compared to the values reported previously.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.1
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• pp.76-87
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• 2015

The present study examines the Saekgyeong (Classic of Husbandry; 1676), an agricultural manual dating from the Joseon Dynasty (1392-1910), and the agricultural thought of its author by Park Se-dang (pen name: Seogye; 1629-1703), a scholar. Its purpose lies in exploring the value of contemporary urban agriculture based on an examination of the attitudes toward agriculture, the values pursued through agriculture, and the ways of dealing with and using land as evinced by the classic and its author. Confirmed through an examination of Park's agricultural philosophy and the Saekgyeong, the results of the present study are as follow. First, there is the socioeconomic value of pursuing the stability of and promoting the economic independence of indigent petty peasants through productivity improvement. Second, there is the experiential value of exploration through experience and agricultural field practice for study. Third, there is the environmental value of endeavoring to overcome an infertile natural environment through agricultural methods that sought to accommodate the land by reading the flow and phenomena of nature. Fourth, there is the practical value of compiling the Saekgyeong and seeking to broaden its use as a guidebook containing agricultural methods appropriate to the land and the wisdom for life.8) When examined in terms of contemporary urban agriculture, the significance of the four values above is as follows: the socioeconomic effect of encouraging urban agricultural activities as a means of welfare for socially alienated classes and promoting the creation of jobs; the enhancement of the significance of study through hands-on activities from an educational perspective; the recycling and recovery of resources and the enhancement of environmental consciousness for the recovery of urban ecology; and a practical spirit that seeks to contribute directly to society through academic research that contributes to practical life and approaches familiar to the populace. The present study sought to find the value of urban agriculture, under discussion in diverse ways in recent years, in the thoughts of our ancestors, who pondered on agriculture. Despite differences in the periodic background, the significance of the present study lies in its in-depth reexamination of the fundamental significance of diverse agricultural values that are being pursued today.

• Journal of Life Science
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• v.27 no.3
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• pp.295-300
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• 2017

This study examined the association between genotypes of the isocitrate dehydrogenase 3, beta subunit (IDH3B) gene and economic traits in an $F_2$ population of Duroc and Jeju (South Korea) native black pigs (JBPs). The genotypes was determined the presence/absence of a 304-bp insertion/deletion fragment in the promoter region of the IDH3B gene for JBP, Duroc, and their $F_1$ and $F_2$ progeny. Three genotypes (AA, AB and BB) were found in the $F_1$ and $F_2$ populations, but there was no AA genotype found in JBP and no BB in Duroc. Association analysis results showed the significant differences with carcass weights (CW), backfat thicknesses (BFT) and eye muscle area (EMA) (p<0.05), but not with growth traits including body weights and average daily gains at different stages, reproductive traits including teat numbers, and crude fat contents (CFAT) measured in longissimus dorsi (p>0.05). The $F_2$ pigs possessing the IDH3B BB homozygote had heavier CW ($72.92{\pm}11.133kg$), thicker BFT ($25.75{\pm}6.06mm$), and larger EMA ($23.82{\pm}4.825cm^2$) than those from the other genotypes (p<0.05). These results were estimated that there are biological roles related with IDH3B genotypes resulting development of EMA, BFT, and CW but not with intramuscular fat deposition during late period of pig production. Our findings suggest that the 304-bp insertion allele of porcine IDH3B may be a genetic marker for marker assistant selection for improving meat productivity of the Jeju Black pig and Duroc-related molecular breeding systems.

• Journal of Life Science
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• v.22 no.5
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• pp.642-649
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• 2012

The southern coast of Korea is important for the ark shell ($Scapharca$ $broughtonii$) aquaculture, but the productivity was rapidly reduced during the previous decade by mass mortality. To overcome this economic loss, investigations only focused on environmental factors, and microbiological researches were performed insufficiently. In this study, two sites (Gangjin and Jinhae bay) were selected for their high and low rate of mortality, respectively, and the existence of microflora from underwater sediments in the bodies of $S.$ $broughtonii$ was analyzed. We screened the whole body of each sample and chose unique colonies, which exhibit alpha- and beta-hemolytic activity, for identification. The microflora in $S.$ $broughtonii$ was less variable than sediments, and restricted species were isolated. We identified 17 genera of 88 species and 16 genera of 64 species from the two bays, respectively. A major proportion was comprised of $Bacillus$ species, with the $Bacillus$ $cereus$ group being the most common species among the $Bacillus$ strains, while $Paenibacillus$, $Lynsilbacillus$, and $Vibrio$ species were the second most abundant species. At the genus level, there were no significant microbial differences between the two coastal regions. 64 species were isolated from rare site (Jinhae bay), but more species (88) with greater variety were isolated from the frequent site (Gangjin bay). Therefore, it was assumed that the cause of mass mortality lay in the difference in specie-level diversity, and conducting investigations on the diagnosis of pathogenic species by challenging tests using isolated unique species.

• Journal of agricultural medicine and community health
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• v.41 no.1
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• pp.1-12
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• 2016

Objectives: In establishing policies for agricultural safety, evaluating injury burdens as well as investigating the rates and characteristics of work injury is important. This study investigated the types and characteristics of agricultural injury subjective burdens. Methods: By analyzing the injured farmers identified in the 2013 Korean Farmers' Occupational Injury Survey, the burdens caused by injuries were categorized using one direct cost item (medical costs) and five indirect cost items (including productivity decreases and wage increases). Statistical differences among the burden items were analyzed using logistic regression analysis according to the characteristics of the farmers and their farm injuries. Results: Among the subjective burdens indicated by the 457 injured farmers, disruption to work was most common. The major influences on each subjective burden item are as follows: for the item of disruption to work, age, time of injury occurrence, treatment period, and farming machine use were influential; for an increased family member's burden of farm works, the number of family members and treatment period were influential. Regarding cost burden of treatment, the results varied according to whether or not the patient was hospitalized and annual income. Conclusion: Subjective burdens induced by indirect costs rather than those induced by direct costs were found to be higher in ratio. In regard to each burden item, the results varied according to the characteristics of the farmers and their farm injuries. To support injured farmer, setting goals to reduce indirect cost burdens and preparing concrete methods is necessary.

• Korea Journal of Hospital Management
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• v.3 no.1
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• pp.1-33
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• 1998

The purpose of this thesis is to study theoretical access to the methods that have been used for the research of occupational stress, thereby providing management methods of occupational stress of hospital workers. With a stress model of hospital workers set up from the viewpoint of organization management, 929 sets of questionnaires were collected from intern doctors, resident doctors, nurses, nursing aides, pharmacists, medical technicians, workers in patient affairs(reception and medical insurance workers), administrators and clerks from the 8 hospitals in Seoul with more than 500 beds. Upon variance analysis, correlation analysis and regression analysis of the collected questionnaires, this work examined how differences in stress caused by specific occupations and formulated a method of stress management for the hospital workers. The results are as follows. 1) If some duties of the nurses suffering from role-overloaded stress are transferred to the nursing aides dissatisfied with insufficient role, the two grunting groups can be satisfied at the same time. It is also necessary to transfer some jobs of the overloaded workers in patient affairs to the administrators, or the other way around. To reduce stress of conflict and ambiguity of role caused by the obscure division of roles between the workers, the role of each occupation should be delineated and the clear division of roles should be translated into action strictly according to that delineated. 2) Stress of inefficiency of organization from which the student doctors suffer can be relieved by management of participation. If they have access to the process of decision-making in general hospital affairs and consequently their understanding and the autonomy of job performance are promoted, such stress will be reduced. 3) To cope with stress of career development from which nurses, medical technicians, administrators, workers in patient affairs suffer, it is necessary to establish whether they have a chance to revive their careers, whether there are any ways of remotivation for less contributive workers, and whether they encourage each other to develope their careers. If they are given a chance to develope their careers, such stress will be relieved. 4) Pharmacists, suffering from stresses of living and personal relations, have strong cohesive power among themselves and organize a well-integrated team; thereby reducing the stress of personal relations and increasing productivity. 5) For administrators and student doctors confined to lesser social supports and for nurses and workers in patient affairs whose recognition of stress and job satisfaction are affected by social supports, emotional and informational supports for job performance help alleviate an individual's mental, and physical stress. 6) In addition to the above-mentioned stress-management methods, if an organizational coping strategy is provided according to the types of stress from the general viewpoint of the whole group of hospital workers, it would be of great help to managing stress. For example, the redesign of jobs, the management of objective, the improvement of working environment, the formation of an autonomous working group and various working plans can be set up for those who suffer from stress related to inappropriate role, while career counseling and development of career process can be provided for those dissatisfied with career development. Participation in the process of decision-making and the restructuring of the organization are needed for those who suffer from stress of malfunctioning organization, whereas creation of a supportive organizational atmosphere is desired for those who feel stressed due to personal relations. As well, such organizational coping strategies. as the increase of welfare facilities, seminars and educational programs and provision of health-promotion facilities can be provided.