• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.408-414
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• 2011

The purpose of this study was to find out optimum cultivated regions for rice organic farming. The organic and conventional rice as control were grown in three different places : secluded hill paddy field for Hapcheon, normal rural paddy field for Sancheong, and suburban paddy field for Jinju from 2005 to 2006. In secluded hill paddy field, the organic material and pesticide to control pest and disease were input twice for organic and conventional rice cultivation. However, in normal rural and suburban paddy field, those were input three times for organic and conventional rice cultivation. The occurrence of sheath blight in organic farming was higher than in conventional farming. Whereas brown planthopper population per 20 plant was significantly high 10.1~19.5 for conventional farming compared with 4.4~10.0 for organic farming. For that reason, the density of the brown planthoppers was higher in organic farming than those in conventional farming. Dominated weeds occurred in organic and conventional paddy field were namely Monochoria vaginalis, Ludwigia prostrata, and Cyperus difformis. The population per 20 plant and dried weight per $m^2$ of weeds were higher in 121 and 50.5 g for organic paddy field. The productivity of rice in different cultivated regions for organic farming was $2.96Mg\;ha^{-1}$ in hill paddy field, $4.03Mg\;ha^{-1}$ in normal rural and suburban paddy field. Toyo-taste value and ratio of perfect grain of milled rice were not different by cultivated regions in both farming system.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.500-505
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• 2014

In recent years, organic ginseng cultivation has increased because customers prefer organic ginseng products due to the morphological quality as well as the safety such as the residuals of chemically-synthesized pesticides. Therefore, some of paddy and upland fields were converted into organic ginseng fields. Soil chemical properties, soil microflora, and soil-inhabiting animals were investigated in paddy-converted and upland organic ginseng fields in Sangju city, Korea. There was few difference in the soil chemical properties, and the soil nutrient concentrations, such as nitrate-N, Av. $P_2O_5$ between the two field types, and exchangeable cations such as K and Ca were within the ranges which are recommended by the standard ginseng-farming manual. Changes in microflora were also assessed by analyzing phospholipid fatty acid composition. Overall, indicators of microbial groups were greater in the upland field than in the paddy-converted soil, but they were not significantly different. In addition, there was no significant change in the abundance of nematodes, collembolans, and mites between the two field types probably because of the high variation within the field types. In this study, it was suggested that soil chemical and biological properties for organic ginseng cultivation were greatly influenced by the variation of topography and soil management practices rather than field types. Further study may be needed to investigate the influence of these factors on soil chemical and biological properties in organic ginseng soils.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.184-184
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• 2017

Organic matter is very important and essential factor to maintain productivity of paddy field. But as meat consumption and the demand of grain increase, the demand of forage also increased gradually in Korea. So the amount of organic matter in paddy field have been declined gradually by the reduction of return of rice straw for the forage use for cattle. There is not enough alternative resources for forage, we guess this trend of organic matter decline in paddy field would continue for the time being in Korea. So this study was performed to confirm the variation of organic matter and change of rice yield to select suitable rice cultivars which yield reduction is small in condition of organic matter decrease in paddy field. To confirm the change of rice growth and yield in condition of organic matter decrease in paddy field, we transplanted 10 rice cultivars which yield reduction are small in low fertilizer condition. We transplanted it Buan where double cropping of winter barley continues several years on June 10. Planting density were $70plants/3.3m^2$ Fertilizer amount was $N-P_2O_5-K_2O=9-4.5-5.7kg/10a$ and fertilizer split application of nitrogen was basal-tillering stage-panicle initiation = 50-20-30%. And in the other cultivation management, we observed rice standard culture of NICS. In paddy field where withdraw straws of barley and rice, the organic matter content showed tendency to decrease as the years go on. During rice cultivation season, organic matter decreased little by little, but it increased again after rice harvest season. Rice yield was more in order of Sodami, Chunghaejinmi and Saenuri. We judge that there is an advantage in rice yield of rice cultivars which have later heading date because of suitable ripening temperature. Although Sobibyeo and Shindongjinbyeo showed high yield, head rice yield decreased severely owing to chalky and cracked rice.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.604-609
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• 2005

Runoff characteristics of organic matters and nutrients from greenhouse site in paddy field area were investigated during the irrigation period in 2004. The greenhouse selected which situated near the Nam river, Jinju, Korea used the ground water as the irrigation purpose. And, the rotating system of paddy field to upland was adapted as a cropping system which is a typical practice in this area. Various items such as total phosphorus(T-P), total nitrogen(T-N), dissolved oxygen(DO), BOD, etc. were observed to figure out the seasonal and spatial variation in the study sites. it was found that the risk of water pollution due to the contamination of nutrients in canals in green house sites, and their neighbouring small sized streams are much higher than those in ordinary paddy field areas. Further surveys and investigations are required to find out the counter measures to reduce water pollution occurred in greenhouse sites.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.629-647
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• 2018

This study was carried out to investigate the economic value of organic rice production using gelatin chitin microorganisms in eco-friendly complex, Gongsan, Naju city. The soil condition of experiment paddy field was Jeonbuk series and silt loam with a slightly poor drainage. Except for the high effective silicate, the chemical characteristics of soils used were included in the optimum range of paddy soils in Korea. In growth, plant length, tiller number, ear number, and ear length were observed to be higher in conventional paddy fields than organic paddy fields. However, number of grain per panicle and grain filling ratio (%) were higher in organic paddy fields than conventional paddy fields. Incidences of diseases and insect pests were slightly higher in the organic paddy fields. Water weevil, sheath blight, rice leaf roller and rice blast were more occurred in organic paddy field. On the other hand, false smut was higher occurred in conventional paddy field. There was a significant negative correlation between rice sheath blight and rice leaf roller, and rice yield. In the milled rice quality, the quality of organically cultivated milled rices was lower by the increase of broken rice than that of conventionally cultivated milled rices. The quality and palatability of rice were higher in organic cultivation with decreasing of protein content. Net income of conventionally and organically cultivated rice was 360,000 won/10a and 610,000 won/10a, respectively. Premium net income of the organically cultivated rice was 68%.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.217-227
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• 2010

This paper was studied $CO_2$ respiration rate with physicochemical properties of soils at wetland, paddy field and forest in Nongju-ri, Haeryong-myeon, Suncheon city, Jeollanam-do. Soil temperature and $CO_2$ respiration rate were measured at the field, and soil pH, moisture and soil organic carbon were analyzed in laboratory. Field monitoring was conducted at 6 points (W3, W7, W13, W17, W23, W27) for wetland, 3 points (P1, P2, P3) for paddy field and 3 points (F1, F2, F3) for forest in 10 January 2009. $CO_2$ concentrations in chamber were measured 352~382 ppm for wetland, 364~382 ppm for paddy field and 379~390 ppm for forest, and the average values were 370 ppm, 370 ppm and 385 ppm, respectively. $CO_2$ respiration rates of soils were measured $-73{\sim}44\;mg/m^2/hr$ for wetland, $-74{\sim}24\;mg/m^2/hr$ for paddy field and $-55{\sim}106\;mg/m^2/hr$ for forest, and the average values were $-8\;mg/m^2/hr$, $-25\;mg/m^2/hr$ and $38\;mg/m^2/hr$. $CO_2$ was uptake from air to soil in wetland and paddy field, but it was emission from soil to air in forest. $CO_2$ respiration rate function in uptake condition increased exponential and linear as soil temperature and soil organic carbon. But, it in emission condition decreased linear as soil temperature and soil organic carbon. $CO_2$ respiration rate function in wetland decreased linear as soil moisture, but its in paddy and forest increased linear as soil moisture. $CO_2$ respiration rate function in all sites increased linear as soil pH, and increasing rate at forest was highest.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.897-899
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• 2012

In this study, spatial analyses of chemical properties were studied to find inter-relation among these properties from 5 year old general paddy field after arable land rearrangement and remodeled paddy field near 4 river project. In addition, comparison of spatial variations between two paddy fields was performed to characterize paddy fields by different formation and provide interpretation of these variations and parameters (Semivariogram and Kriging) from spatial analyses. Total of 400 ($20{\times}20$) soil samples were taken at 5 m interval from 1 ha of 5 year old general paddy field and analyzed. Total number of 54 ($6{\times}9$) soil samples were taken from remodeled paddy fields at 10m interval for the analyses. The results of pH, available Phosphate and organic matter among the analyzed results were used for interpretation. The pH values were relatively high from Gumi region. The values of available Phosphate and organic matter showed greater variant coefficients and this represented that there were greater heterogeneity in available phosphate and organic matter distributions across one paddy field. The values of skewness and kurtosis as absolute values, showed almost normal distributions. The paddy field in Ansung had available Phosphate (72.8) ${\fallingdotseq}$ pH (73.8) and greater values of organic matter (159.3), while upland in Gumi had the range value of organic (6.5) < available Phosphate (33.5) < pH (46.6). Based on these results, younger soils (0 year old) require more sampling to characterize the whole field than 5 year old soils.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.387-401
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• 2017

This study was performed in order to investigate disease, insect damage, growth and yield characteristics of green maize by organic paddy-upland rotation system. This experiment also was to select optimum variety for organic paddy-upland rotation cultivation. This experiment was conducted at Anseong-si Gyeonggi province of Korea in 2016. The varieties used in this study are green maize of total 8 varieties. Green maize was planted at rotational upland field and continuing upland field and tested for comparison. In case of average occurrence of 4 major disease for green maize, rotational upland field was higher than that of continuing upland field. Heukjinjuchal and Daehakchal were the lowest occurrence by less than 2% among 8 varieties. Average damage of 8 varieties by Ostrinia furnacalis larva, which is the main pest in green maize was higher in rotational upland field than that of continuing upland field. Chalok 4 and Heugjeom 2 were judged to be resistant varieties to 4 major disease among 8 varieties. The average yield of green maize per 10a in rotational upland field decreased to 85% level of continuing upland field and Chalok 4 showed the highest yield by 789.0 kg/10a among 8 varieties. The most suitable varieties in organic paddy-upland rotation system were judged to be Chalok 4, Heukjinjuchal and Heukjeom 2.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.349-349
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• 2017

This study was performed in order to investigate disease, insect damage, growth and yield characteristics of green maize by organic paddy-upland rotation system. This experiment also was to select optimum variety for organic paddy-upland rotation cultivation. This experiment was conducted at Anseong-si Gyeonggi province of Korea in 2016. The varieties used in this study are green maize of total 8 varieties. Green maize was planted at rotational upland field and continuing upland field and tested for comparison. In case of average occurrence of 4 major diseases for green maize, rotational upland field was higher than that of continuing upland field. Heukjinjuchal and Daehakchal were the lowest occurrence by less than 2% among 8 varieties. Average damage of 8 varieties by Ostrinia furnacalis larva, which is the main pest in green maize was higher in rotational upland field than that of continuing upland field. Chalok 4 and Heugjeom 2 were judged to be resistant varieties to 4 major diseases among 8 varieties. The average yield of green maize per 10a in rotational upland field decreased to 85% level of continuing upland field and Chalok 4 showed the highest yield by 789.0 kg/10a among 8 varieties. The most suitable varieties in organic paddy-upland rotation system were judged to be Chalok 4, Heukjinjuchal and Heukjeom 2.

• Journal of Korean Society of Rural Planning
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• v.23 no.4
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• pp.39-48
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• 2017

National Institute of Environmental Research (NIER) has proposed new methodology for estimating unit load in order to overcome the limitations of past unit load based on short-term and local area based data. In the case of agricultural land, however, the results presented by NIER are still limited because of various agricultural activities and farmland characteristics. In this study, liquid manure treated paddy field and organic farming upland were selected for considering agricultural diversity. Four different methods for evaluating unit load were used for comparing previous research results. The results of different methods presented various trends compared with those of existing studies. Paddy field treated liquid manure was 1.3 times higher for T-N load and 3.1 times for T-P load than conventional paddy field. Conventional upland was 4.4 times higher for T-N load and 1.8 times higher for T-P load than organic farming upland. In the case of non-conventional farmland, this study showed different values with the unit loads presented by NIER. This implies that it is necessary to review and apply the unit loads considering various agricultural conditions when establishing environmental policy and rural planning.