• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.4
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• pp.1-8
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• 2012

This study is to assess the reduction of non-point source pollution loads for rice straw surface covering of upland crop cultivation at a watershed scale. For Byulmi-cheon watershed ($1.21km^2$) located in the upstream of Gyeongancheon, the HSPF (Hydrological Simulation Program-Fortran), a physically based distributed hydrological model was applied. Before evaluation, the model was calibrated and validated using 9 rainfall events. The Nash-Sutcliffe model efficiency (NSE) for streamflow was 0.62~0.78 and the NSE for water quality (Sediment, T-N, and T-P) were 0.68, 0.60, and 0.58 respectively. From the field experiment of 16 rainfall events, the rice straw covering reduced surface runoff average 10 % compared to normal surface condition. By handling infiltration parameter (INFILT) in the model, the value of 16.0 mm/hr was found to reduce about 10 % reduction of surface runoff. For this condition, the reduction effect of Sediment, T-N, and T-P loads were 87.2, 28.5, and 85.1 % respectively. The rice straw surface covering was effective for removing surface runoff dependent loads such as Sediment and T-P.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.237-241
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• 2005

The physical and chemical characteristics of soils in a small watershed were investigated and the effect of geology and land use on soil quality were examined by using multivariate statistical methods, principal components analysis and discriminant analysis. It was considered that the accumulation of salts in the farmland soils indicated by electrical conductivity, contents of cations and anions and pH was caused by fertilizer input during cultivation. The contents of inorganic components are increased as following order: upland > orchard > paddy field > forest. The results of two discriminant analyses using water extractable inorganic components and their ratios by land use were also clearly classified by discriminant function 1 and 2. In discriminant analysis by components, discriminant function 1 indicated the effect of fertilizer application and increased as following order: upland > orchard > paddy field > forest soil.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.1
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• pp.89-97
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• 2015

This study is to assess the effect of non-point source pollution discharge loads between tillage and no-tillage applications for upland crop areas using SWAT (Soil and Water Assessment Tool) watershed modeling. For Byulmi-cheon small rural catchment ($1.17km^2$) located in upstream of Gyeongan-cheon watershed, the rainfall, discharge and stream water quality have been monitored in the catchment outlet since 2011. The SWAT model was calibrated and validated in hourly basis using 19 rainfall events during 2011-2013. The average Nash-Sutcliffe model efficiency and $R^2$ (determination coefficient) for streamflow were 0.67 and 0.79 respectively. Using the 10 % surface runoff reduction from experiment results for no-tillage condition in field plots of 3 % and 8 % slopes under sesami cultivation, the soil saturated hydraulic conductivity for upland crop areas was adjusted from 0.001 mm/hr to 0.0025 mm/hr in average. Under the condition, the catchment sediment, T-N (total nitrogen, TN), and T-P (total phosphorus, TP) discharge loads were reduced by 6.9 %, 7.4 %, and 7.7 % respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.49-54
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• 1988

The present experiment was conducted to investigate causes affecting the reduction of red pepper production in the continuous cultivation upland soil from 1985 to 1986 in Imsil Chonbuk Province. The results obstained are summarized as follows: 1. Area ratio of continuous cultivation 2 years was 12.7%, 3 years 6.8% and over 4 years 48.9%. 2. Soil hardness and volume of solid and liguid of red pepper continuous cultivation soil were higher than those of one year cultivation, while pH and content of organic matter of continuous cultivation soil were low. The exceeding optimum level of phosphorus and potassium appeared factors affecting and reduction of red pepper of continuous cultivation soil. 3. Microflora density in continuous cultivation soil was high but bacteria/fungi (B/F) and actinomycetes/fungi (A/F) ratio were low. 4. The density of soil nematodes in continuous cultivation soil were higher than that in one year cultivation soil, however, the steeper and better drainage soil lowered the density of nematodes. 5. Continuous cultivation over 4 years showed 14.3% of plants diseased by phytophthora while 0.7% in one year cultivation soil.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.2
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• pp.100-106
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• 2014

The present study investigated variations in soil microbial communities by fatty acid methyl ester (FAME) and the chemical properties at 24 sites of upland soils in Gyeongnam Province. The electrical conductivity of the soil under potato cultivation was significantly higher than those of the red pepper and soybean soils (p < 0.05). The gram-negative bacteria community in potato soil was significantly lower than those in the garlic and soybean soils (p < 0.05). The communities of actinomycetes and arbuscular mycorrhizal fungi in the red pepper soil were significantly higher than those in the potato soil (p < 0.05). In addition, the cy17:0 to 16:$1{\omega}7c$ ratio was significantly lower in red pepper, soybean, and garlic soils compared with potato soil, indicating that microbial stress decreased. Consequently, differences in soil microbial community were highly associated with cultivated crop species, and this might be resulted from the difference in soil chemical properties.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.3
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• pp.163-170
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• 2001

The objective of this study was to evaluate land cover classification of PyeongTaeg area by Landsat Thematic Mapper Data June, 1997. This study was also to make more correct reference data using DGPS, aerophoto, and topographical chart etc.. The result of the area of paddy and upland were estimated 4,949 $\textrm{km}^2$ and 16,157 $\textrm{km}^2$, respectively. Correctness of estimation by using DGPS, aerophoto, topographical chart were shown over 90% correct in case of rice paddy field, water, and sea, while upland, vinyl house, forest, grassland, village were shown low correctness. Total average accuracy was shown to be 85.8%. Correctness of paddy field showed high value of 92%, showing that use of remote sensing data was proved to be effective methods to estimate spatial distribution and cultivation status of paddy field. Classification result of sea, water area, downtown had higher correctness, while upland, vinyl-house, grassland were proved to be relatively low correctness because of it's small area and mixed distribution.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.6
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• pp.111-118
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• 2020

This study developed a rainwater harvesting system for the irrigation of upland on sloping area. The assessment of water supply capacity was evaluated in farm field experience. This system consists of a water catchment device and a collapsible storage tank. The water catchment device was designed to collect runoff water in natural channel of 500 mm width into a pipe of 50 mm inner diameter. The device has funnel-shaped plan and cross-section of square. The storage capacity of the collapsible water tank was caculated to meet the water demand for irrigation in 30 a cultivated land for 10-year frequancy drought. The tank has a cuboid shape with a capacity of 30 ㎥, 5 m in width and length, 1.2 m in height. This system can supply 92% of the water required for drop irrigation of red pepper and 88% of the water required for drop irrigation of onions in 30 a cultivation land during the month of May and June. In the case of 16-dry days of 10-years frequency, this system is capable to irrigate 100% of required water for red pepper and onion, 76.7% of required water for Omija (Schisandra chinensis), and 51.5% of required water for autumn kimchi cabbage.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.562-573
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• 2017

Some symbiotic characteristics of native Korean Rhizobium leguminosarum biovar viciae were analysed to get some informations desirable for cultivation of hairy vetch (Vicia villosa Roth) using its symbiont in Korea. The size of indigenous populations of R. leguminosarum biovar viciae was higher in seven upland soils showing $1.7{\times}10^2{\sim}5.8{\times}10^4cells\;g{\cdot}soil^{-1}$, which appeared to be 10% and 37% higher for cultivated and uncultivated soils of hairy vetch, respectively, than seven paddy soils with $1.7{\times}10^2{\sim}1.7{\times}10^4cells\;g{\cdot}soil^{-1}$. In symbiotic potentials, however, the yields of hairy vetch treated with 10-fold-diluted ($10^{-1}$) inoculum and 1000-fold-diluted ($10^{-3}$) one was 11.2% and 8.8% more, respectively, in paddy than upland. Hairy vetch inoculated with either strain KHR 106 from Sacheon or strain KHR 120 from Yesan among native Korean R. leguminosarum biovar viciae isolates was of similar yield increment of 16% (p < 0.05) in upland soils with native R. leguminosarum biovar viciae of $5.8{\times}10cells\;g{\cdot}soil^{-1}$. In case of coinoculation of the two strains, however, the yields was not significantly increased. In especial, isolate KHR 106, KHR 120, and KHR 122 from Suwon, which has also good symbiotic effectiveness, showed different protein profile patterns each other. As a result, hairy vetch is possibly able to use atmospheric nitrogen through symbiotic relationship with diverse native R. leguminosarum biovar viciae in Korean arable lands. For safe and good production of hairy, however, the use of superior strains with high symbiotic effectiveness and competitiveness will be desirable.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.1
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• pp.121-130
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• 2019

The purpose of this study is to determine the amount of irrigation water for upland crop growth based on the 30 year of historical rainfall data and the water management guidelines as a reference. Five regions and ten crops were selected by their cultivation size. The changes of soil moisture contents were calculated using daily mean rainfall and irrigation demand. This study assumed that crops are irrigated when the soil moisture contents fell below of the field capacity for more than 5 days, which is the drought condition defined by RDA. The maximum irrigation water requirements was 167.2 mm for chinese cabbage during the growing season, which was followed by corn (112.0 mm), daikon (102.3 mm), spinach (66.1 mm), lettuce (56.7 mm), pepper (46.5 mm), potato (33.9 mm), sweet tomato (27.4 mm), peanut (11.5 mm) and bean (10.3 mm), The results of this study could contribute to providing valuable data to determine the capacity of irrigation facilities and to establish the emergency operation plans under extreme unfavorable weather condition (heat wave, etc.) for crop growth.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.4
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• pp.55-64
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• 2021

The expansion of upland crop cultivation in rice paddy fields is recommended by the Korean government to solve the problem of falling rice price and reduction of rice farmer's income due to oversupply of rice. However, water use efficiency is significantly influenced by the land use change from paddy field to upland. Therefore, this study aimed to evaluate the water budget of soybean grown in using APEX (Agricultural Policy and Environmental eXtender) model. The amount of runoff was measured in a test bed located in Iksan, Jeollabu-do and used to calibrate and validate the simulated runoff by APEX model. From 2019 to 2020, the water budget of soybean grown in uplands were estimated and compared with the one grown in paddy fields. The calibration result of AP EX model for runoff showed that R² (Coefficient of determination) and NSE (Nash-Sutcliffe efficiency) were 0.90 and 0.89, respectively. In addition, the validated results of R² and NSE were 0.81 and 0.62, respectively. The comparative study of each component in water budget showed that the amounts of evapotranspiration and percolation estimated by APEX model were 549.1 mm and 375.8mm, respectively. The direct runoff amount from upland was 390.1 mm, which was less than that from paddy fields. The average amount of irrigation water was 28.7 mm, which was very small compared to the one from paddy fields.