• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.1
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• pp.35-42
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• 2018

Objectives: The objectives of this study are to research the usage characteristics of asbestos-containing building materials and to conduct exposure risk assessment by applying no. 2016-230 "Methods of Risk Assessment of Asbestos-Containing Buildings" from the Ministry of Environment. Methods: One hundred buildings located in the Seoul and Gyeonggi-Incheon area were chosen, with 29 in Seoul, 20 in Incheon, and 51 in Gyeonggi-do Province. The year of construction was divided between three buildings in the 1970s, 11 buildings in the 1980s, 42 buildings in the 1990s, and 44 buildings in the 2000s. The bulk samples were analyzed by using a polarizing microscope after a pre-process using a stereomicroscope in a hood with an HEPA filter. This study defined ACMs(asbestos-containing materials) as asbestos when the content percentage was over 1% in the analysis result. Methods and standards of risk assessment of asbestos-containing building materials were conducted by refering to no. 2016-230 "Method of Risk Assessment of Asbestos-Containing Buildings" from the Ministry of Environment. The risk of exposure to ACMs was rated by a score based on three categories(high, middle, low risk of asbestos exposure). Results: In this study, 30 of the 100 buildings and 36 of the 416 bulk samples(8.6%) were found to have had asbestos. Asbestos was detected at a high rate, in 18 out of 42, in buildings constructed in the 1990s and at the lowest rate(7 out of 44) for buildings constructed in the 2000s. As a result of the evaluation according to no. 2016-230 "Method of Risk Assessment of Asbestos-Containing Buildings" of the Ministry of Environment, the risk assessment level of two asbestos-containing building materials was found to be "Medium", and 28 buildings materials were found to be at the "Low" level. Conclusion: As asbestos is regulated by the government, it is required to conduct active management and implemention by introducing methods of risk assessment of asbestos exposure that are supported by data from various situations. In the case of buildings owned by individuals, building owners should be aware of the risk of exposure to asbestos.

• The Journal of the Petrological Society of Korea
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• v.28 no.3
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• pp.195-215
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• 2019

Geopark is a new system for development of the local economy through conservation, education, and tourism that is an area of scientific importance for the earth sciences and that has outstanding scenic values. The Hwaseong Geopark, the candidate for Korean National Geopark is composed of 10 geosites: Gojeongri dinosaur egg fossils, Ueumdo, Eoseom, Ddakseom, Goryeom, Jebudo, Baengmiri Coast, Gungpyeonhang, Ippado and Gukwado geosites. In this study, geosites, geoheritages, and geotrails of the Hwaseong Geopark were described in detail, and the value and significane as a geopark were also discussed. The geology of the Hwaseong Geopark area belonging to the Gyeonggi Massif consists of the Precambrian metamorphic and meta-sedimentary rocks, Paleozoic sedimentary and metamorphic rocks, Mesozoic igneous and sedimentary rocks, and Quaternary deposits, indicating high geodiversity. The Gojeongri Dinosaur Egg Fossils geosite, designated as a natural monument, has a geotrail including dinosaur egg nest fossils, burrows, tafoni, fault and drag fold, cross-bedding. Furthermore, a variety of infrastructures such as eco-trail deck, visitor center are well-established in the geosite. In the Ueumdo geosite, there are various metamorphic rocks (gneiss, schist, and phyllite) and geological structures (fold, fault, joint, dike, and vein), thus it has a high educational value. The Eoseom geosite has high academic value because of the orbicular texture found in metamorphic rocks. Also, various volcanic and sedimentary rocks belonging to the Cretaceous Tando Basin can be observed in the Ddakseom and Goryeom geosites. In the Jebudo, Baengmiri Coast, and Gungpyeonghang geosites, a variety of coastal landforms (tidal flat, seastacks, sand and gravel beach, and coastal dunes), metamorphic rocks and geological structures, such as clastic dikes and quartz veins can be observed, and they also provide various programs including mudflat experience to visitors. Ippado and Gukwado geosites have typical large-scale fold structures, and unique coastal erosional features and various Paleozoic schists can be observed. The Hwaseong Geopark consists of outstanding geosites with high geodiversity and academic values, and it also has geotrails that combine geology, geomorphology, landscape and ecology with infrastructures and various education and experience programs. Therefore, the Hwaseong Geopark is expected to serve as a great National Geopark representing the western Gyeonggi Province, Korea.

• Journal of agricultural medicine and community health
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• v.9 no.1
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• pp.83-108
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• 1984

Out of a total of 58 species of helminthic and protozoan parasitic infections in Korea, so far 38 species were reported as intestinal parasites of man. Quite a few species of the intestinal parasitic infections have long been prevalent throughout the country and this has been a significant public health problem. In this paper, current status and transition of the intestinal parasitic infections in the past years were presented. Chronological reviewing of data show background and prospects of change in the prevalence of infections. In the national prevalence survey on parasitic infections conducted once every five years since 1971, stool examinations were done by both cellophane thick smear and brine flotation techniques. Every egg positive case of Ascaris lumbricoides and Clonorchis sinensis was further examined by Stoll's dilution egg counting technique. In 1981, perianal swab using adhesive cellulose tape was added for Enterobius infection. For protozoan cyst examination conducted by province and city in '81, fecal specimens were fixed in SAF solution and examined by the formalin-ether concentration technique. High prevalence of parasitic infection in ana before the 1960s can be easily understood from the data given by the Ministry of Health and Social Affairs in 1967. From a parasite control point of view, the 1960s was the preparatory period particularly for control of soil-transmitted helminthiasis. Several organizations which have contributed to parasite control were founded in this period and the prevention law of parasitic infections was passed in '66. In the '70s, overall prevalence rates of the common intestinal parasitic infections, which were highly prevalent in the past were turned into reduction phase for the first time. The '80s can be said to be an active control period of parasitic infections. Intestinal helminths According to the reports of the national prevalence survey on parasitic infections, the prevalence of helminthic infections was 84.3%(number of person examined:24,887) in '71, 63.2%(27,178) in '76, and 41.1%(35,018) in '81. By area, the prevalence rate in '81 was 35.1%(20,569) in urban areas and 49.6%(14,447) in rural areas. Intestinal nematodes Ascaris lumbricoides The prevalence of Ascaris infection has decreased significantly in recent years. Among students, the prevalence was 55.4%, in '69 and decreased to 4.7% in '83. In the national prevalence surveys, the prevalence decreased to 13.0% in '81 from 54.9% in '71. By area, the prevalence decreased to 8.5% in '81 from 46.4% in '71 in urban area and 19.4% in '81 from 59.6% in '71 in rural area. By age, the prevalence has become in recent years relatively even in all age groups, although higher prevalence used to be seen in young age groups of around 10 years old, particulary in the highly prevalent rural areas. By sex, the prevalence was higher in the female than in the male. Unfertilized egg positive rates among the ascariasis cases increased gradually up to 55.4% on the average in '81. The intensity of the infection was also significantly decreased. Trichuris trichiura Trichuris infection had also decreased to 23.4% in '81 from 65.4% in '71. By area, the decreasing tendency of the prevalence became faster in urban areas than in the rural areas. The prevalence in urban and rural areas in '71 was 69.7%, and 63.1% respectively and decreased to 19.5% and 29.0% respectively in '81. By age, the prevalence reached a peak at the 10-14 age group and showed relatively even distribution throughout all age groups. By sex, the prevalence was close in young age groups, but in the 30s or over age group, especially in rural area, the prevalence was significantly higher in the female than in the male. The prevalence has much fluctuated depending in the area. The prevalence in rural areas surveyed in the '80s shows a range between 20.9% and 73.7% by locality. It is anticipated that the prevalence of Trichuris infection will drop more rapidly, when mass treatment is conducted. Hookworms Hookworm infection by mostly Ancylostoma duodenale and a few by Necator americanus has decreased to a negligible levels in recent years. In the national prevalence surveys, the prevalence was 10.7% in '71, 2.2% in '76, and 0.5% in '81. The prevalence was higher in rural areas than in urban areas. Wide application of multi-specific anthelminthics in the ascariasis control programmes conducted in the past decade appear to have been effective against hookworm infection. Trichostrongylus orientalis As in the case with hookworm infection, the prevalence of Trichostrongylus infection has reached a negligible levels. In the national prevalence surveys, the prevalence was 7.7% in '71, 1.0% in '76 and 0.2% in '81. Enterobius vermicularis In the national prevalence survey in '81, the egg positive rate was 12.0%. Higher prevalence is expected when examined repeatedly. The prevalence rate was 10.3% in urban area and 14.6% in rural area. In recent surveys conducted in rural areas among schoolchildren, the prevalence was 32.4% in Gimhae Gun in '82 and 64.1% in Yeongyang Gun in '83. By age, the egg positive rate was higher in young age groups of around 10 and sharply decreased in age groups of around 20 and then somewhat increased again in middle age groups. By sex, the prevalence was higher in the female than in the male. Strongyloides stercoralis Strongyloides stercoralis infection has rarely been found in Korea. Three cases were reported in 1914. And 0.1-0.5% were found infected out of 2,642 persons examined at the prisoner-of-war camp on Geojedo in 1956. One case was reported in '54 and '82, respectively. Anisakis spp. No systematic survey has been conducted for anisakiasis In Korea. So far, only several cases have been found 1 case in Seoul in '71, 5 cases in Busan in '81 and 1 case in Busan in '84. Intestinal trematodes Metagonimus yokogawai In the national prevalence survey conducted in 1981, the egg positive rate was 1.24% on the average. High endemic areas are located in the southwestern part of Korea. The prevalence in Hadong Gun was 29.1% on the average in '79. In a survey conducted in 76, the prevalence was 44.0% in Gwangyang, 55.0% in Gogseung and 29.0% in Gurye. The infection is closely correlated with raw sweetfish consumption in these areas. Other intestinal trematodes A human case of Heterophyes heterophyes was reported in 1914. Several species were reported in the '80s : 17 cases of Fibricola seoulensis, 9 cases of Pygidiopsis summa, 8 cases of Heterophyes heterophyes nocens, 1case of Heterophyopsis continua, 2 cases of Stellantchasmus falcatus, 1 case of Stictodora sp., 1 case of Echinostoma hortense, and 4 cases of Echinochasmus japonicus. As the intermediate hosts, snakes and frogs play a role for F.seoulensis and fish for the rest of the species. Intestinal cestodes Taenia saginata and T. solium Egg positive rates in the national prevalence survey were 0.7% in '76 and 1.1% in '81. The prevalence in '81 was 0.6% in urban area and 1.8% in rural area. The proglottid positive rate in Jeju Do was 19.2% on the average. On Udo, Jeju Do in 1983, the egg positive rate among the inhabitants was 2.9%. Hymenolepis nana In the national prevalence survey, egg positive rates were 0.6% in '76 and 0.4% in '81. No difference was seen in the prevalence by area and sex. Hymenolepis diminuta Infected cases were reported : 3 in '64 and I in '66. Egg positive rate in '81 was 0.01% in the national prevalence survey. Diphylobothrium latum So far, about 30 cases have been reported. The cases have been reported more frequently in recent surveys. Mesocestoides sp. A case was reported from a hospitalized patient in Seoul in '67. Spirometra erinacei Two cases were reported in '84 following reidentification of the adult worms collected in '74. Intestinal protozoa Out of a total of 23 species of human protozoan infections in Korea, 13 species were reported as intestinal protozoa : Entamoeba histolytica, E coli, Endolimax nana, Iodamoeba b$\ddot{u}$tschlii, Dientamoeba fragilis, Giardia lamblia, Chilomastix mesnilii, Embadomonas sp., Enteromonas hominis, Trichomonas hominis, Isospora belli, I. Hominis(Sarcocystis hominis), and Balantidium coli. Since the first report on intestinal protozoan infections in 1925, there have been quite a few survey data on the prevalence of the infection. It was found reviewing the data chronologically that up to the early '70s the infection was prevalent around a 30-50%. After that, the protozoan cyst positive rate has shown the tendency of gradual decrease throughout the country. Protozoan cyst survey conducted in Seoul and several provinces in 1981 revealed infection rates of 8.9%(1,310) in Gangweondo, 10.7%(1,703) in Gyenggi Do, 11.7%(1,032) in Jeonra Buk Do, 9.1%(4,116) in Jeonra Nam Do, and 1.4%(5,275) in Seoul. Entamoeba histolytica In the survey conducted by province in '81, the cyst positive rate was 0.8% in Gangweon-do, 0.3% in Gyeonggi Do, 1.4% in both Jeonra Buk Do and Jeonra Nam Do, and 0.2% in Seoul. Giardia lamblia In the survey by province in '81, cyst positive rates were 2.2% in both Gyeonggi Do and Jeonra Buk Do, 1.9% in Jeonra Nam Do, 0.5% in Gangweon Do, and 0.9% in Seoul. Balantidium coli Two cases were reported. One in 1930 and the other in '74. Isospora belli and I. Hominis(Sarcocystis hominis) Isospora belli was reported : 1 case in '56 and 3 cases in '66. I. Hominis, recently identified to be synonymous with Sarcocystis hominis, was reported : 3 cases in '66. Other intestinal protozoa The protozoan parasites other than the above mentioned are generally treated as commensal, although some of them are considered to be pathogenic. The data of '81 show that about 10% of the inhabitants are still infected with protozoa.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.4
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• pp.229-241
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• 2006

Global air temperature has risen by $0.6^{\circ}C$ over the last one hundred years due to increased atmospheric greenhouse gases. Moreover, this global warming trend is projected to continue in the future. This study was carried out to evaluate spatial variations in rice production areas by simulating rice-growth and development with projected high resolution climate data in Korea far 2011-2100, which was geospatially interpolated from the 25 km gridded data based on the IPCC SRES A2 emission scenario. Satellite remote sensing data were used to pinpoint the rice-growing areas, and corresponding climate data were aggregated to represent the official 'crop reporting county'. For the simulation experiment, we used a CERES-Rice model modified by introducing two equations to calculate the leaf appearance rate based on the effective temperature and existing leaf number and the final number of leaves based on day-length in the photoperiod sensitive phase of rice. We tested the performance of this model using data-sets obtained from transplanting dates and nitrogen fertilization rates experiments over three years (2002 to 2004). The simulation results showed a good performance of this model in heading date prediction [$R^2$=0.9586 for early (Odaebyeo), $R^2$=0.9681 for medium (Hwasungbyeo), and $R^2$=0.9477 for late (Dongjinbyeo) maturity cultivars]. A modified version of CERES-Rice was used to simulate the growth and development of three Japonica varieties, representing early, medium, and late maturity classes, to project crop status for climatological normal years between 2011 and 2100. In order to compare the temporal changes, three sets of data representing 3 climatological years (2011-2040, 2041-2070, and 2071-2100) were successively used to run the model. Simulated growth and yield data of the three Japonica cultivars under the observed climate for 1971-2000 was set as a reference. Compared with the current normal, heading date was accelerated by 7 days for 2011-2040 and 20 days for 2071-2100. Physiological maturity was accelerated by 15 days for 2011-2040 and 30 days for 2071-2100. Rice yield was in general reduced by 6-25%, 3-26%, and 3-25% per 10a in early, medium, and late maturity classes, respectively. However, mid to late maturing varieties showed an increased yield in northern Gyeonggi Province and in most of Kwangwon Province in 2071-2100.

• Journal of dental hygiene science
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• v.15 no.2
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• pp.159-165
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• 2015

A self-administered survey was conducted on the dental hygiene students at three different colleges located in Gyeonggi Province and South Chungcheong Province respectively from October, 2013, to the same month of 2014 to grasp their oral health management behavior, differences in plaque index according to plaque index systems and the correlation of the two. And their plaque index was measured. The findings of the study were as follows: 62.8% of the respondents replied they got a dental checkup over the past year, and 84.1% answered they received preventive dental treatment once at least or more. 80.5% replied they used a fluorine-containing dentifrice. 90.9% answered they used the rolling method to brush their teeth, and 50.0% replied it took three minutes to brush their teeth. They got a mean of 27.88 when O'leary index was used among plaque index systems. Their PHP index and PHP-M index were respectively a mean of 1.30 and a mean of 12.12. Their plaque index became lower when they spent more time brushing their teeth, and the toothbrushing time made a statistically significant difference to that (p<0.05). The factor that exerted the largest influence on plaque index was whether to brush teeth for the sake of oral health (B=-9.747, t=-3.752, p<0.001) or not. That made a statistically significant difference to it. The above-mentioned findings illustrated that more patients visited dental clinics than before to receive preventive dental treatment or to get dental checkups, and that toothbrushing time and whether to brush teeth for the sake of oral health or not were identified as the oral health management behaviors to affect plaque index.

• Journal of dental hygiene science
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• v.10 no.5
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• pp.307-314
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• 2010

This study aimed to measure such features of emotional responses perceived by students as learning climate, department living stress, and perceived helplessness to analyze their effects on major satisfaction among students at the department of dental hygiene; to do this, a survey was conducted with 431 students, regardless of college year, who were at the department of dental hygiene in four colleges in Gyeonggi Province, Daejeon, and Chungcheong Province. An existing emotion scale which went through the generalization process was used to draw a multiple model in the combination form in order to collect emotional factors affecting college students' satisfaction with their major, which had existed as a hypothetical proposition, and make overall interpretation of relevance through the explainable, predictable modeling process by measuring emotional factors and phenomenal description of the level of general perception. The results showed that major satisfaction was very significantly affected by emotional features among students at the department of dental hygiene, which needs to be treated as an important factor to enhance expertise related to major learning and improve students' living.

• Journal of Animal Science and Technology
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• v.54 no.4
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• pp.247-253
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• 2012

Ultrasound measures of back fat thickness (UBF), eye muscle area (UEMA) and marbling score (UMS) and carcass measures of carcass weight (CW), backfat thickness (BF), eye muscle area (EMA) and marbling score (MS) were available on 26,129 Hanwoo steers. Statistically significant differences by regions of the farms location and birth years-seasons for the steers taken ultrasound measures and their carcass measures (p<0.01) were found. Steers in Gyeonggi province showed the highest values in ultrasound measures and carcass traits except in BF compared to steers in the other provinces. Comparing between ultrasound and carcass measures, UBF was thicker in general than BF in all regions except in Daejeon city. UEMA was higher than EMA in all regions except in Gyeonggior in Jeju provinces. Especially, the difference in Jeonnam province between UEMA and EMA was $7cm^2$ while the differences between UMS and MS ranged from 0.9 to 2.26 depending on the regions of steers located. Steers born in spring showed greater ultrasound or carcass values than those born in autumn. However, carcass measures of steers born in autumn were greater than those born in spring, 2009 except MS. The pearson and residual correlations were 0.63 and 0.65 between UBF and BF, 0.31 and 0.32 between UEMA and EMA and 0.56 and 0.56 between UMS and MS, respectively.

• Korean Security Journal
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• no.61
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• pp.255-283
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• 2019

This study conducted a survey of 315 facility security workers in Daejeon, South Chungcheong Province and Gyeonggi Province for about a week from August 7 to August 13, 2019 to identify the impact of work environment and job stress on job satisfaction, and finally collected 293 of the total 315 parts of the data, excluding non-response and inappropriate responses. The STATA 14.2 Statistical Package Program was used for analysis of the collected data, frequency analysis was performed to determine the distribution ratio of the subjects, and reliability analysis and correlation analysis were performed with respect to the established key variables. Next, t-test and one-way ANOVA were conducted to verify differences in work environment, task stress and task satisfaction factors according to demographic characteristics, and the results were as follows: There were differences in work environment, job stress and job satisfaction recognition depending on demographic characteristics. In detail, the factors for the work environment indicated significant differences in age, academic background, number of years of service, wages and types of service in the recognition of the work environment. Job stress factors indicated significant differences in age, education, wages and types of service in job stress recognition. In job satisfaction factors, age, academic background, number of years of service and wages (monthly benefits) showed significant differences in job satisfaction recognition. In addition, the results of multiple regression analyses to identify the working environment, job stress, and job satisfaction are as follows. The working environment has had a positive impact on job satisfaction, and the better the job environment, promotion and organizational characteristics, the higher the job satisfaction. It has been shown that job stress has had a negative impact on job satisfaction, conflict of relationship (promoting colleagues). job autonomy increases job satisfaction, and job satisfaction decreases when job requirements and job insecurity increase. In terms of the impact of work environment on job satisfaction, the higher the work promotion, job environment and organizational characteristics, the higher the job satisfaction level, the report showed. According to these studies, the better the working environment, the lower the job stress, and the lower the job stress, the higher the job satisfaction. In addition, the better the working environment, the more satisfied the job was found to be, and the empirical research result was verified that improvement of the working environment of security workers can reduce job stress and improve job satisfaction through improvement of the working environment.

• Journal of Korea Water Resources Association
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• v.56 no.4
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• pp.261-272
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• 2023

In recent years, natural disasters such as heavy rainfall and typhoons have occurred more frequently, and their severity has increased due to climate change. The Korea Meteorological Administration (KMA) currently uses the same criteria for all regions in Korea for watch and warning based on the maximum cumulative rainfall with durations of 3-hour and 12-hour to reduce damage. However, KMA's criteria do not consider the regional characteristics of damages caused by heavy rainfall and typhoon events. In this regard, it is necessary to develop new criteria considering regional characteristics of damage and cumulative rainfalls in durations, establishing four stages: blue, yellow, orange, and red. A classification model, called DSCM (Disaster Severity Classification Model), for the four-stage disaster severity was developed using four machine learning models (Decision Tree, Support Vector Machine, Random Forest, and XGBoost). This study applied DSCM to local governments of Seoul, Incheon, and Gyeonggi Province province. To develop DSCM, we used data on rainfall, cumulative rainfall, maximum rainfalls for durations of 3-hour and 12-hour, and antecedent rainfall as independent variables, and a 4-class damage scale for heavy rain damage and typhoon damage for each local government as dependent variables. As a result, the Decision Tree model had the highest accuracy with an F1-Score of 0.56. We believe that this developed DSCM can help identify disaster risk at each stage and contribute to reducing damage through efficient disaster management for local governments based on specific events.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.460-466
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• 2009

Carbon fixation and density of crops are important to estimate carbon uptake or emission by agricultural production activities and to establish life cycle inventory of crops for assessment of climate change impact. In this study, regional carbon fixation and density in each part of 14 crops, harvest index, and ratio of aboveground to underground were investigated to estimate biomass of 14 crops in Korea by using agricultural statistics data. Biomass yield of potato was $16.5ton\;ha^{-1}$, which was the highest, and those of rice, sweet potato, and garlic were $10.5ton\;ha^{-1}$, $8.7ton\;ha^{-1}$, and $7.5ton\;ha^{-1}$ respectively. Biomass yield of Green onion was the lowest as $2.8ton\;ha^{-1}$. Carbon density of 14 crops were in the order of potato ($6.4ton\;ha^{-1}$), rice ($4.2ton\;ha^{-1}$), sweet potato ($3.4ton\;ha^{-1}$), rape ($2.9ton\;ha^{-1}$) and garlic ($2.8ton\;ha^{-1}$). Regional distribution of carbon contents for each crop mapped revealed that carbon fixation of rice, soybean, sesame, garlic, and green onion were the highest in Jeonnam province, barley, red pepper, and watermelon in Gyeongnam, perilla in Chungnam, peanut in Gyeongbuk, rape and carrot in Jeju, sweet potato in Gyeonggi, potato in Gangwon. The results can be applied for assessing life cycle inventory of crops and crop productivity using remotely sensed data.