• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.368-373
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• 2014

Ammonia loss from urea significantly hinders efficient use of urea in agriculture. The level of nitrous oxide ($N_2O$) a long-lived greenhouse gas in atmosphere has increased mainly due to anthropogenic source, especially application of nitrogen fertilizers. There are reports in the literature showing that the addition of zeolite to N sources can improve the nitrogen use efficiency. This study was conducted to evaluate nitrous oxide ($N_2O$) and ammonia ($NH_3$) emission by mixed treatment of urea and zeolite in upland crop field. Urea fertilizer and zeolite were applied at different rates to study their effect on $N_2O$ emission during red pepper cultivation in upland soils. The $N_2O$ gas was collected by static closed chamber method and measured by gas chromatography. Ammonia concentration was analyzed by closed-dynamic air flow system method. The total $N_2O$ flux increased in proportion to the level of N application. Emission of $N_2O$ from the field increased from the plots applied with urea-zeolite mixture compared to urea alone. But urea-zeolite mixture treatment reduced about 30% of $NH_3$-N volatilization amounts. These results showed that the application of urea and zeolite mixture had a positive influence on reduction of $NH_3$ volatilization, but led to the increase in $N_2O$ emission in upland soils.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.296-302
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• 1994

To alter the paddy field to upland, mole drainages were constructed under 30cm of the surface of(Jeon buk silt loam) which is not appropriate for cultivation of upland crops. Intervals of the moles were 50cm, 100cm and 150cm and diverted to upland for soybean cultivation. By construction of the mole drainage, about 75% to 45% of the rainfall was drained and the ground water level was maintained below 40cm. After a year of drainage, the blocky surface was changed to granular or nutty structure which is common in upland fields. Oxidation was progressed to the deep layer because of soil dryness. Soybean yield were increased by 11% to 22% in the mole drained plots, but wet injury was occurred in the nontreated check plot with relatively poor growth status.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.4
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• pp.256-262
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• 2003

The emission of methane and nitrous oxide was measured from fields of upland rice and soybean. Rice cultivar, Daejinbyeo, was seeded in a row of 30 cm space in upland soil on April 28, 2001. The fields were irrigated with sprinkler irrigation or natural precipitation. Three soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong, were sown with seeding space of $60{\times}15cm$ on June 16, 2001. Gas samples were collected twice a week during the growth period, and methane and nitrous oxide were analyzed. Methane emission from upland rice field of sprinkler irrigation was $3.5kg\;CH_4\;ha^{-1}$. However, negative emission of methane, $-1.7kg\;CH_4\;ha^{-1}$, was observed in upland rice field of natural precipitation. Total nitrous oxide emission from upland rice field of sprinkler irrigation was $50.8kg\;N_2O\;ha^{-1}$, while the emission in the field of natural precipitation was $8.3kg\;N_2O\;ha^{-1}$. Global warming potentials (GWP) in the upland rice fields of sprinkler irrigation and natural precipitation were 15,822 and $2,216kg\;CO_2\;ha^{-1}$, respectively. Methane emissions from fields of soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong were -14.7, -4.3 and $4.8kg\;CH_4\;ha^{-1}$, respectively. Total nitrous oxide emissions from fields of soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong were 4.7, 4.6 and $3.0kg\;N_2O\;ha^{-1}$, respectively. Total GWPs for soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong were 1152, 1323 and $1027kg\;CO_2\;ha^{-1}$, respectively.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.25-33
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• 1983

This study was carried out to investigate the transplanting time, optimum fertilization and harvesting method, chemical contents and physical properties of burley tobacco in paddy field. The results obtained as follows. 1. It is recommendable to transplant after March. 29 to escape the frost injury. By reducing compound fertilizer and whole plant stalk curing, advanced the. last priming date by 5-8 days. 2. Total alkaloid, total nitrogen and phosphorus contents of cured leaf was comparable to those of upland-produce(1 tobacco, but potassium and chloride contents some what high. 3. Filling power and combustibility was also comparable to upland, and filling power was increased by reducing fertilizer and whole plant stalk curing. 4. In the 20o reducing fertilizer-5 Primings volt. the yield was some what decreased, but visual quality and value per 10a were high. 5. The total raw income of tobacco and rice cropping was increased 124~170% than that of rice cropping.

• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.19-26
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• 1996

The crop rotation of rice and ginseng in paddy field has very important meaning because up-land field suitable for ginseng cultivation is now being insufficient day by day in main ginseng production area. This studies were conducted to define basic problems related to ginseng cultivation and replanting in paddy field. In Keumsan district, the most serious problem on ginseng cultivation in paddy field was excess of mineral salts left behind in the soil of rice cultivation. The amounts of organic matters, CEC and the mineral elements including potassium were higher in the soil of paddy ginseng field compared to those of upland. Plant growth of 3 and 4 year old ginseng and root yield of four year old ginseng cultivated in paddy field of 1st and replanting were not decreased compared to those of 1st - planting of up-land field, but those were significantly decreased in replanted compared to those of first planted upland field. Crop rotation with ginseng and rice in paddy field seemed to be a good way to avoid hazards of continuous cropping of ginseng with it's outyield of root and less infection of diseases. Amounts of crude saponin and ginsenosides of ginseng cultivated in paddy field were not differ from those of upland field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.6
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• pp.577-584
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• 1994

A field trial was carried out to select suitable crops for diverted upland from paddy field and to investigate response of several forage crops to soil properties and ground water levels of the diverted upland at Suwon area of Korea in 1992 and 1993. Experiments were conducted in sandy loam plot and comparatively clay loam plot having higher ground water level. Rye (Paldang), triticale (Shinki), italian ryegrass (Tetraflorum) were used as wintering forage crops and maize(Suwon 19), sorghum-sudangrass hybrid(Pioneer855F), pearl millet(Suwon 6), japanese millet (King) were used as summer forage crops. Growth and yield of forage crops were better and higher in sandy loam soil having low ground water level. Among wintering forage crops, triticale recorded the highest forage yield. Rye showed high forage yield in sandy loam soil and italian ryegrass hardly survived in diverted upland of Suwon area during winter. Among summer forage crops, forage yield of sorghum-sudangrass hybrid was highest. Yield of japanese millet was not affected by soil conditions in both plots. Yields of pearl millet and maize remained relatively low in both plots.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.1
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• pp.49-56
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• 1986

To obtain the information of low chlorine leaf production, the chlorine content of the soil and cured leaf in Burley tobacco growing area was investigated. The results obtained are as follows. 1. The chlorine concentration in soil at transplanting time in Kwang-ju growing area was higher than in Jeon-ju(1983), and paddy field sell showed higher concentration of chlorine than upland field in Jeon-ju(1984). The chlorine concentration in soil was different between years, locations, and cultivated land (paddy field and upland field), but the concentration, on the whole, was under the levels that might effect the leaf quality. 2. The chlorine concentration In soil was highest around todays after transplanting, and after harvesting, the concentration decreased to half of transplanting time. 3. The distribution of chlorine through the parts of tobacco plant showed remarkable difference between years, locations, cultivated land and growing stages. 4. There was significant positive correlation between chlorine concentration in top soil and chlorine content of cured leaf. 5. Chlorine content of cured leaf in Kwang-ju area(1.79%) was higher than that of Jeon-ju area(O.79%), relatively. 6. It was considered that the accumulation of salt from the sea by sea. wind did not main factor of high leaf chlorine content in seaside district.

• Korean Journal of Plant Resources
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• v.35 no.6
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• pp.720-761
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• 2022

This study surveyed the vascular flora present in abandoned paddy field type of 237 forest wetlands in Korea to provide baseline data for conservation, management, and monitoring and to support preparation for damage and climate change. The study period was from April 2015 to November 2021. The vascular flora of 237 forest wetlands by abandoned paddy field type were identified to consist of 128 families, 510 genera, 1,022 species, 27 subspecies, 87 varieties, 10 forma, and 1,146 taxa. 4 taxa were identified as grade II endangered wild plants, 185 taxa were identified as northern lineage plants of the Korean Peninsula, 43 taxa were endemic to the Korean Peninsula, and 58 taxa were rare plants as designated by the Korea Forest Service. Further, 296 taxa were floristic target plants and there were 86 taxa of invasive alien plants. According to wetland preference, 79 taxa (6.9%) were obligate wetland plants, 103 taxa (9.0%) were facultative wetland plants, and 61 (5.3%) taxa were facultative plants. Additionally, 66 taxa (5.8%) were facultative upland plants, and 837 taxa (73.0%) were obligate upland plants.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.02a
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• pp.95-100
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• 2000

• Journal of Biosystems Engineering
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• v.43 no.2
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• pp.83-93
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• 2018

Purpose: This study derived the consumed power and load characteristics of a tillage operation performed in an upland field located in Seomyeon, Chuncheon, Rep. Korea, where potatoes and cabbages were cultivated in two crops. Methods: A plow and rotavator were mounted on a tractor with 23.7 kW of rated power to perform the tillage operation. The work conditions were determined, considering the actual working speed of the tillage operation performed by the local farmers. The power consumption of the rear axle, engine, and power take-off (PTO), PTO torque, and tractive force were measured under each work condition. The consumed power and load characteristics were analyzed using their average values. Results: The rotary-tillage operation consumed more engine power than the plow operation for the same tractor-transmission gear condition. The PTO in the rotary-tillage operation and the rear axle in the plow operation consumed the most power. The power consumption of the engine and the PTO for the rotary-tillage operation tended to increase as the transmission gears of the tractor and the PTO became higher. In contrast, the rear-axle power consumption was insignificant. In addition, the PTO torque tended to rise as the tilling pitch increased. For the plow operation, the drawbar power and the rear axle power accounted for 68-90% of the engine power. The engine and rear axle power, drawbar power, and tractive force tended to rise as the working speed increased. Conclusions: The power consumption and load characteristics differed for the plow and rotary-tillage operations. They may also differ depending on the soil conditions. Therefore, the power consumption and load characteristics in various work environments and regions should be analyzed, and reflected in the design of tractors and working implements. The results derived from this study can be used as a reference for such designs.