• 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 CROP SCIENCE
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• v.45 no.2
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• pp.97-102
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• 2000

This experiment was conducted to investigate the changes of harvest index and the relationship between harvest index and yield determination factors by different planting times in the determinate soybean cultivars, Shinpaldal and Danbaeg. Optimum planting were 23 May in 1995 and 1996. Late planting were 13 June in 1995 and 6 June in 1996. Growth period from planting to physiological maturity (R7) was shortened as planting time was delayed in two cultivars due to shortening of reproductive growth period in Shinpaldal, and of vegetative growth period in Danbaeg. Stem weight was distinctly decreased in late planting compared to optimum planting, but seed weight of both cultivars was not different between planting times. Also, seed number per pod and harvest index were significantly increased in late planting and the high correlation was found between two factors. It was suggested that increase of harvest index in late planting would be related with high assimilate use efficiency due to increase of sink capacity. The results of correlation and principal component analysis for yield determination factors showed that main factor on yield determination was pod number per plant at R5 stage associated with dry matter accumulation during early reproductive growth period, seed number per pod and harvest index were the second factor, and one hundred seed weight was the third factor. The result of this experiment indicated that yield determination in soy-bean was dependent mainly on pod number per plant related to dry matter accumulation by early reproductive growth period, and the increase of seed number per pod and harvest index could compensate for yield decrease by shortening of vegetative growth period in late planting. Such result suggests that optimum planting date can be delayed from mid May to early June in improved soybean cultivars in Korea.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.281-281
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• 2017

Recently, global warming by greenhouse gas effect is getting danger and danger for human life and agriculture at present. In Indonesia, according to heavy rain in the agriculture land is often covered by excess water in result crop growth would be affected negative. This water stress triggers roots failure in anaerobic condition for upland crop because of limiting roots respiration. Chili pepper grows in upland sometimes in touch with waterlogging due to rainfall and /or over flow water from river in Indonesia. In this case, roots growing is inhibited by effect of shortage of oxygen at root cap. Therefore, the objective of this study is to observe the plant behavior in waterlogging using mahor local genotypes (Ferosa, Laris, Romario) in Sumatra. The experiment was kept by at 1cm depth water above the soil surface as a waterlogged treatment for ---days. As a result, waterlogging affected plant growth of chili negatively, especially for roots growth. Almost roots were getting bad and changed color for brown during waterlogging. A significant negative effect for nutrient absorption by roots was found in dry weight of all varieties during waterlogging. Dry weight of roots was decreased by 81.4% and 67.6%, and those of aerial part decreased by 74% and 67.2% compared with control in Ferosa and Romario at 1week after treatment. On the other hand, dry weight of roots was decreased only 35% in Laris. Therefore, Laris has a tolerance for waterlogging compared to with other varieties. Also, Laris in SPAD value was kept initial level during waterlogging however those of Ferosa and Romario decreased. Finally, due to impact of waterlogging, it may be the roots become failure because of less aerenchyma formation under anaerobic condition. We need confirm aerenchyma formation morphologically in the future.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.81-86
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• 2013

For organic farming, green manure crops such as leguminous forages and barley have been broadly used to improve soil fertility and soil physical and chemical properties by repeatedly cutting and mulching them directly as winter crop in the field in the rotation. In this investigation we selected 78 agricultural farm corporations as well as individual organic farmhouses related to crop rotation from greenmanure crops to main crops in order to analyze the relationship of cropping system between main crops and green manure crops. The results showed that the green manure crops were divided into two groups as leguminous and nonleguminous crops, representing that those are limited to specific climate and farming systems of regions. Also the 10 or less green manure crops including sudangrass, hairyvetch, italian ryegrass, sorghun, buckwheat, oat, pea, rye, clover, and canola which belong to leguminous crops which are presently cultivated from the organic farmhouses within the rotational crop system. We also confirmed that the major main crops are sweet potato, soybean, corn, tobacco, spinach from usage frequency analyzed by NetMiner H 2.6 which was used to estimate the rotational cropping system among the green manure crops and main crops.

• Korean Journal of Remote Sensing
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• v.14 no.4
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• pp.343-352
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• 1998

Spectral reflectance data of upland crops at OSMI bands were collected and evaluated for the feasibility of crop discrimination knowledge-based on crop calendar. Effective bands and their ratio values for discriminating corn from two other legumes were defined with OSMI equivalent bands and their ratio values. For corn discrimination from two other legumes, peanut and soybean, June 22 among measurements dates was the best since all OSMI equivalent bands and their ratio values in June 22 were highly significant for corn separability. Phenological growth stage of a silage corn (rs510) could be estimated as a function of spectral reflectance in vegetative stage. Five growth stage prediction models were generated by the SAS procedures REG and STEPWISE with OSMI equivalent bands and their ratio values in vegetative stage.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.61-73
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• 1983

This study was conducted to obtain fundamental informations on the improvement of cropping system to increase in land utilization rate and crop production. In order to group the characteristics of areas, Chungnam province was classified into 4 classes: Suburb (Daedeog Gun, Cheonwon Gun), Plain (Nonsan Gun, Dangjin Gun) Coastal (Seosan Gun, Boryeong Gun) and Hilly region (Gongju Gun, Cheongyang Gun). 100 farm households were sampled from each region, and cropping system and utilization state of paddy and upland in 1982 were surveyed. The results obtained were summarized as follows: 1. Average utilization rate of upland was 161.9 % The utilization rate of upland at plain was highest (188.9 %), and that at suburb showed lowest value (152.0%). 2. Number of crops cultivated at upland was 32 kinds. Among the rate of planting area of each crop. soybean showed highest rate of 18.8%, barley 15.4%, red-pepper 13.1% and chinese' cabbage 10.1% respectively, but the red pepper showed highest rate of planting area at suburb, the barley at hilly region and the soybean at plain and coastal region. 3. Average utilization rate of paddy was 115.6% and the utilization rate of paddy at suburb showed the highest value (140.0%) and that at coastal region the lowest value (108.2%). 4. 12 kinds of crops were cultivated at paddy before or after rice cultivation. Among the crops cultivated at paddy before or after rice cultivation, barley showed the highest area rate (5.0%) of cultivation and strawberry the next but the strawberry showed the highest area rate of cultivation at suburb and barley at other regions. 5. The cropping systems at upland were divided into single cropping and double cropping. Types of double cropping at upland were classified into 38 types by the combinations of crops. Among the types of double cropping, the rate of cultivation area of soybean after barley combination was 35.0%, but at suburb the rate of this type of cropping system was low and the double cropping of vegetable combinations showed high rate. 6. Types of double cropping at paddy were classified into 6 types. As a whole, double cropping of barley after rice combination showed highest rate of cultivation area (42.8%) among crop combinations but at suburb, the area rate of this type cropping was low and cultivation of fruit vegetable after rice showed highest rate. The area rate of post - cropping to rice was 76.3% of whole double cropping area at paddy and significantly higher than the rate of precropping to rice. 7. Some kinds of crop combinations were consisted of same family or closely related crops and the characteristics of the crop rotation between those crops are almost same. The area cultivated those unreasonable crop combinations were 19.09 ha. 8. At upland, planting area of the cereal crops, vegetale crops and industrial crops crops and industrial crops was 88.92ha, 93.70ha and 21.80ha respectively. The Planting area of cereal crops was significantly less than that of vegetable crops. 9. Most of all the research reports on the cropping system from 1910 to 1980 were about the post cropping after rice harvest. The objectives of researches could be classified into 14 kinds and the important objectives of researches were the planting time, the amounting of manuring, the quantity of seeding, the transplanting time, the ridging method, the sowing method and the variety test.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.81-86
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• 2015

"Youhan" (Hordeum vulgare L.), a new whole-crop barley cultivar, was developed by the breeding team at National Institute of Crop Science, RDA in 2012. Youhan has the growth habit of III, a light green and mid-sized leaf, hooded and lax-type spikes. The cultivar showed 107 cm of culm length, 641 spikes per $m^2$. The heading date of Youhan was May 1, which is one day later than that of the check cultivar "Yuyeon" in upland, and 2 days earlier than that of Yuyeon in paddy field. The maturation time was similar to check cultivar Yuyeon on June 4 in upland and May 31 in paddy field. In terms of winter hardiness and resistance to lodging and disease, Youhan also performed better than the check cultivar. The average forage dry matter (DM) yield in the regional yield trial was approximately 12.6 ton $ha^{-1}$ and 12.0 ton $ha^{-1}$ in upland and paddy field, respectively, which were 6% and 5% higher than that of the check. The yield also showed 7.3% of crude protein, 26.8% of ADF (acid detergent fiber), 47.8% of NDF (neutral detergent fiber), 67.7% of TDN (total digestible nutrients), and a higher grade of silage quality for the whole-crop barley. Fall sowing cropping of Youhan is recommended only in those areas where the average daily minimum-mean temperatures in January are higher than $-8^{\circ}C$, and it should not be cultivated in mountainous areas of Korea.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.2
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• pp.107-114
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• 2004

NPS pollutant loads from sandy clayey and clayey loam runoff plots were measured. Runoff plots were 2$\times$10 m in size and 8~10% in slope and paddy area was 4,620 $m^2$. Soybean, corn, tobacco and control (natural weed) were cultured. Precipitation during the growing season of June to October, 2002 was 869.5 mm. Runoff and water quality were measured more than 10 times during the measurements depending on the growing stage. Pollutants loads were estimated by using respective concentration and runoff volume. Runoff occurred when daily rainfall exceeded about 30 mm. The largest runoff was observed from the paddy but pollutant loads were larger from upland crops than those from paddy. SS loads from paddy and upland were 1.4 ton/ha/yr and 3.1~4.3 ton/ha/yr, respectively. COD loads 30 kg/ha/yr and 66~90 kg/ha/yr, T-N loads 13 kg/ha/yr and 14~23 kg/ha/yr, T-P loads 1 kg/ha/yr와 4 kg/ha/yr, nitrate nitrogen loads 1 kg/ha/yr and 4~8 kg/ha/yr, and phosphate phosphorus loads 0 kg/ha/yr and 4~6 kg/ha/yr, respectively. It was concluded that NPS pollutant loads from upland crop culture have greater impact on the quality of the receiving water body than those from paddy culture.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.1
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• pp.87-97
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• 2004

The paper presents the results from the applications of the Water Erosion Prediction Project (WEPP) model to a single plot, and also a small watershed in the Mid Korean Peninsula which is comprised of hillslopes and channels along the water courses. Field monitoring was carried out to obtain total runoff, peak runoff and sediment yield data from research sites. For the plot of 0.63 ha in size, cultivated with com, the relative error of the simulated total runoff, peak runoff rates, and sediment yields using WEPP ranged from -16.6 to 22％, from -15.6 to 6.0％, and from 23.9 to 356.4％ compared to the observed data, respectively. The relative errors for the upland watershed of 5.1 ha ranged from -0.7 to 11.1 ％ for the total runoff, from -6.6 to 35.0 ％ for the sediment yields. The simulation results seem to justify that WEPP is applicable to the Korean dry croplands if the parameters are correctly defined. The results from WEPP applications showed that the major source areas contributing sediment yield most are downstream parts of the watershed where runoff concentrated. It was suggested that cultural practice be managed in such a way that the soil surface could be fully covered by crop during rainy season to minimize sediment yield. And also, best management practices were recommended based on WEPP simulations.

• Asian Journal of Turfgrass Science
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• v.8 no.1
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• pp.37-46
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• 1994

We study on the standing crop and edaphic factor of grasslands in Chulwon near the D.M.Z. The widespread and most abundant grasses are Arundinella hirta and Miscanthus sinensis in the upland fields of D.M.Z. The vascular flora of grasslands in Umi-dong and Sukda-dong near the D.M.Z. and composed of total 25 species, the most important of which ace Arundinella hirta and Miscanthus sinensis These two species contribute greatly to the standing crop of live naterial was in excess of $107.6g /m^2$. Correlation between standing ccop and water content, organic matter, total nitrogen, or avail-able phosphorus of grassland soils in area studied is high significant. It is argued that these edaphic factors affect the growth of grasses in Umi-dong and Sukda-dong grasslands.