• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.3
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• pp.169-174
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• 2002

When the long - lasting stationary fronts were pushed northward by the Pacific Highs in late July, mostly clear skies with intermittent showers were a typical weather of August in Korea. However, torrential rains and flash floods are now a seasonal event of August in recent years. Some meteorologists suspect this unusual phenomenon might be connected with the global change and are concerned about the possibility of change in summer climatic pattern in Korea. August of year 2002 must be remembered to be one of the record breaking months with respect to the rainfall events. In this paper, we analyzed the weather and crop data nationwide for August in 2002, and suggest a few countermeasures necessary to overcome the wet and cool summer impacts on agricultural sector.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.323-331
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• 2013

BACKGROUND: Liquid pig manure(LPM) is a useful resource if it is sufficiently fermented and utilized in the agriculture; it provides nutrients to soils, circulates organic materials and replaces chemical fertilizers(CF) with reasonable costs. Currently, there are not many trials in paddy field to continuously cultivate the crops in winter and summer season using LPM. METHODS AND RESULTS: When cultivating winter forage crops (Whole-crop-barley(WCB), Rye, Triticale, Italian ryegrass(IRG)) and summer feed corns in the rice field, CF was treated with $N-P_2O_5-K_2O$(winter forage crops: 120-100-100kg/ha, summer feed corn: 200-150-150 kg/ha), and subsequently, growth, yields, feed values and chemical properties of soil were investigated. LPM-applied areas in both winter and summer forage crops showed higher plant lengths and tillers than those of CF-applied areas, but the yield in CF-applied areas was higher than that of LPM-applied areas under continuous application of 2 years. Crude protein, neutral detergent fiber(NDF), acid detergent fiber(ADF) and total digestion nutrient(TDN) in feed values showed almost similar results between LPM and CF-applied areas. EC, organic matter, available phosphate and exchangeable cations of soils after the experiment increased in LPM applied areas, and especially, the contents of available phosphate and exchangeable sodium were high. CONCLUSION(S): Considering the above results, it was concluded that if LPM are properly utilized for continuous winter and summer cultivation of feed crops at paddy field, the cultivation costs could be decreased and be helpful to the stable production of domestic feeds.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.108-110
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• 2011

In order to evaluation of beneficial functions for organic farming, we have divided beneficial functions as 9 sub-functions such as flooding control, fostering water resources, purifying the air, mitigating summer climate, purifying water quality, decreasing soil erosion, accumulating soil carbon, conserving biodiversity, and preventing accidents from pesticides. And they were quantified by searching related repots and statistics, and surveying fields. Organic farming, especially organic paddy farming, showed that some functions like fostering water resources, accumulating soil carbon, conserving biodiversity, and preventing accidents from pesticides were higher than conventional paddy farming, while the others were almost similar. The fostering water resources function was evaluated as 4,297 ton $ha^{-1}\;year^{-1}$ to increase about 3.6% comparing with that of conventional farming. New function for accumulating soil carbon at organic paddy fields has been assessed by 4.67 ton $ha^{-1}$ in terms of long periods over 10 years. Considering area of organic paddy farming in Korea and value of carbon price, it was evaluated monetary value as 22.4 to 84.1 billion won using replaced method. It could be also evaluated that flooding control, fostering water resources, purifying the air, mitigating summer climate, purifying water quality, decreasing soil erosion, and preventing accidents from pesticides were 2,980, 123.4, 482.6, 87.5, 0.9, 55.6, and 284.1 billion won, respectively. Conserving biodiversity function would be very big at organic farming though it couldn't be evaluated as monetary value.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.2
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• pp.71-76
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• 2021

In order to establish optimal double cropping system for getting the maximum annual productivity, we investigated annual fresh and dry yields of winter forage crops (WFC), Italian ryegrass (IRG) 'Kowinearly', triticale 'Joseong' and summer forage crop (SFC), 'Jonong' and 'Jowoo' as whole crop silage rice in the paddy field of Yeongseo of Gangwon Province. The double cropping of each crops was applied with 2 standard cultivation method of WFC and SFC from 2018 to 2020. For the WFC, the average percentage of dry matter (29.6%) of IRG 'Kowinearly' was lower than that (35.5%) of triticale 'Joseong'. The average fresh matter yield of IR G 'Kowinearly' was 2,662kg/10a that there was no significant difference from the 2,836kg/10a of triticale 'Joseong'. The average dry matter yield (996kg/10a) of triticale 'Joseong' was more than that (696kg/10a) of IRG 'Kowinearly'. For the summer forage crops, the average percentage of dry matter of whole crop silage rice, 'Jonong' was 34.5% that there was no significant difference from the 35.0% of 'Jowoo'. The average fresh matter yield (5,367kg/10a) of 'Jowoo' was more than that (3,966kg/10a) of 'Jonong'. And the average dry matter yield (1,936kg/10a) of 'Jowoo' was more than that (1,433kg/10a) of 'Jonong'. The total maximum dry matter yield was 2,982kg/10a with the combination of the WFC triticale, 'Joseong' and the SFC whole crop silage rice, 'Jowoo'. In conclusion, the combination of crops that can obtain the maximum yield of high quality forage for double cropping is sowing the WFC triticale, 'Joseong' in mid-October, harvesting 'Joseong' around the end of May and then SFC whole crop silage rice, 'Jowoo', to be transplanted in early June.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.4
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• pp.275-280
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• 2007

This experiment was conducted to investigate the selection of regional double cropping system for production of organic forage in middle part of Korea. The species of forage crop used in this experiment were corn, $sorghum\;{\times}\;sudangrass$ hybrid and japanese millet for summer crops and rye and Italian ryegrass for winter crops. $Sorghum\;{\times}\;sudangrass$ hybrid showed higher DM (dry matter) and TDN (total digestible nutrient) yield than that of corn. Dry matter yield of corn decreased to 56% that of control because of weed. In winter crops, DM and TDN yield of rye is higher than that of Italian ryegrass. Rye was more adequate to produce organic forage in middle part of Korea. We could not find out the difference of nutrient value between each treatments. It means that the amount of nutrient is affected by DM productivity of each crop. The result of this study indicated that $sorghum{\times}sudangrass$ hybrid (summer crop) and rye (winter crop) cropping system could be recommended as producing high yield of organic forage in middle part of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.56-62
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• 1998

Seasonal variations of eelgrass and epiphytic algae in eelgrass beds in Kwangyang Bay were studied from January 1994 to December 1994. A peak of the shoot length and standing crop of eelgrass occurred in summer, but low values were observed in fall and winter. The dominant species of epiphytic algae were Callophyllis rhynchocarpa and Champia sp. In spring and summer, while Polysiphonia japonica and Lomentaria hakodatensis in fall and winter. In contrast to the eelgrass, the standing crop of epiphytic algae showed a minimum in summer. There was a gradual increase in the standing crop of epiphytic algae during fall, and a peak of standing crop occurred in winter. Epiphytic algae accounted for approximately $15\~20\%$ of total plant standing crops of the eelgrass meadows. Correlation analysis with environmental factors indicated that temperature influences on both the standing crop of eelgrass and epiphytic algae. There was a positive relationship between the standing crop of eelgrass and temperature, while there was a reverse relationship between that of epiphytic algae and temperature.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.121-126
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• 2010

Until now, The experiment about the forage crop have been almost not conducted on the reclaimed land. Therefore, this experiment was carried out in order to know productivity of summer forage crop using slurry composting-biofilteration (SCB) liquid fertilizer on reclaimed land of Hwaong and Sukmoon in korea from 2008 to 2009. The forage crops used in this experiment were corn and sorghum${\times}$sorghum hybrid which are used as summer forage crops in South Korea. The experiment was treated with chemical fertilizer (CF), swine slurry (SS) and SCB liquid fertilizer. Dry matter (DM) yield of corn was higher than those of sorghum${\times}$sorghum hybrid in both reclaimed lands but the effect of SCB liquid fertilizer was not appeared. The neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of corn were lower than those of sorghum${\times}$sorghum hybrid. The crude protein (CP) content and in vitro dry matter digestibility (IVDMD) of corn were higher than those of sorghum${\times}$sorghum hybrid. In generally feed values of corn were higher than those of sorghum${\times}$sorghum hybrid. The results of this study showed that summer forage crop cultivation using uses SCB liquid fertilizer on reclaimed land are possible.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.355-363
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• 2018

This study was conducted to investigate suitable rice cultivars for various rice based cropping systems in a paddy field in the Yeongnam plain area. Thirteen rice cultivars (5 early, 3 medium and 5 mid-late maturing cultivars) and three transplanting dates (June 5, June 25 and July 5) were evaluated in this study. The mid-late and early maturing cultivars for the July 5 and June 25 transplanting headed before August 30 which is the safe heading date in the Yeongnam plain area, ranging from Aug. 26 - 28 and Aug. 18 - 23, respectively. The safe harvest time of rice for double and triple cropping systems should be before the middle of October for the cultivation of the succeeding winter crops. The rice yield was the highest for the June 5 transplanting regardless of the rice cultivars, and it gradually decreased as the transplanting date was delayed from June 5 to July 5 due to a decrease in the spikelet numbers per panicle number and in the ripened grain rate. In contrast, the other yield parameters that include the panicle number per $m^2$, the 1,000-brown rice weight, and the ripened grain ratio were not significantly affected. The result indicates that based on the milled rice, heading time and harvest time, a medium maturing cultivar (Haiami and Samdeog) would be applicable to a winter barley/wheat, garlic/onion-summer rice double cropping, while a mid-late cultivar (Saeilmi, Saenuri and Hyunpoom) would be suitable for a spring potato/waxy corn-summer rice double cropping in the Yeongnam plain area. On the other hand, an early maturing cultivar (Unkwang, Jokwang and Haedamssal) would be preferable for a triple cropping because of the short growth period of rice.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.479-484
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• 1999

Rice crop has relatively short growing season during the summer in Korea and, therefore, it is often difficult to acquire cloud-free imagery on time. This study was attempt to define the temporal characteristics of radar backscattering observed from satellite L-band SAR data on different growing stages of rice crop. Six scenes of multi-temporal JERS SAR data were obtained from the transplanting season to the harvesting month of October. Six layers of multi-temporal SAR data were registered on a common geographic coordinate system. Using topographic maps, field collected data, and Landsat TM data, several sample rice fields were delineated from the imagery and their relative radar backscatters were calculated by using a set of reference targets. The temporal pattern of radar backscattering was very distinctive by the growing stage of rice crop. It was also separable between two types of rice fields having different cultivation practices. Considering the temporal characteristics of radar backscattering observed from the study, it is obvious that a certain date of the growing season can be more effective to delineate the exact area of the cultivated rice crop field.

• Proceedings of the Korean Society of Crop Science Conference
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• 1996.05a
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• pp.104-105
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• 1996