• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.60-65
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• 1993

This experiment was conducted to understand the effects of climatic environment on the useful components in Angelicae gigantis radix. The variation of decursin contents in different seven cultivated regions and the relationship between decursin contents and meteorological factors were investigated. The appropriate analytical methods for decursin and decursinol angelate of Angelicae gigantis radix were HPLC method used normal phase column($\mu$-Porasil) and GC method. In different cultivated regions, the variation of decursin contents of Angelicae gigantis radix was relatively great, which were high with 4.86%, 4.75% in Bongwha, Yongcheon respectively and was low with 2.33% in Suwon. There was no significant relationship between decursin contents of Angelicae radix and meteorological factors during growing periods, but was negative correlation in average temperature and precipitation, and positive correlation in diurnal change of temperature, radiation and sunshine hours.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.19
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• pp.69-77
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• 1975

Difference of fatty acid composition of rapeseeds from different regions in Korea and Japan were found. Erucic acid content of the rapeseeds produced in Korea, particulary in Mokpo was higher than that produced in Japan. While, the contents of oleic and linoleic acids produced in Korea were lower than those produced in Japan. It was considered being due to temperature, amount of precipitation and hours of sunshine during the maturing period.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.143-151
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• 2010

The impact of climate change on rice plants in Gangwon province was examined by comparing the climatic conditions during the recent 10 years (2000~2009) with those of normal (1971~2000) years, and by evaluating the rice plant responses. The daily mean air temperature increased by $0.5^{\circ}C$ while the daily range decreased by $0.1^{\circ}C$ as compared with the normal years. During the main rice growing period in field (from June to September) precipitation increased from 900 to 1,051mm and sunshine hours decreased from 704 to 619 hours. The respiration consumption effect during the rice growing period increased by 0.07 as a result of increased air temperature and reduced sunshine hours. The optimum heading date (determined by the mean air temperature for 40 days after the heading) was delayed in Chuncheon, Hongcheon, Wonju, and Gangneung compared with the normal. The maximum climatic yield potential based on mean temperature and sunshine hours for 40 days after the rice heading decreased by 94 kg/10a mainly due to the decrease in sunshine. The mean air temperature for 40 days after the rice heading from 1999 to 2009 in Chuncheon, Cheorwon, and Gangneung was generally above $22^{\circ}C$ implying that yield and quality of rice can be reduced. Therefore, it is necessary to delay the heading date by planting mid- to late-maturing varieties or by changing the transplanting date in order to produce high quality rice and to maintain rice productivity. In addition, it is also important to develop or select cultivars suitable to changing climate for each region in Gangwon province.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.268-275
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• 1982

This study was conducted to obtain basic informations for breeding and improving cultural practices of sesame (Sesamum indicum L.) through investigation of several agronomic characters of 82 major varieties plants in April 20, May 15 and June 20. Stem diameter and plant height were largest in early planting(April 20). On the contrary, they were smallest in late planting(June 15). Therefore, the later planting, the poorer the vegetative growth on the basis of stem diameter and plant height. Number of capsules per plant and number of grains per capsule were 88 and 54, respectively, in the early planting, while they were decreased to 25 capsules and 40 grains in late planting. The percentage of ripeness and 1000 grain weight 78 and 2.3g in the April 20planting while they were 58% and 2.1g in June 20 planting indicating the later planting, the lower the ripeness. Grain yield per m1 in April 20 and June 20 planting was 112 and 18g respectively. Consequently, grain yield significantly decreased as planting delayed. On the basis of the vegetative and reproductive growth, varieties could be classified into early, conventional, late and indetermediate planting adapted groups. The major yield components were highly and postively correlated with accmulated sunshine hours and temperatures confirming that grain yield was closely related with sunshine and temperature. Among the varieties tested, Gurye and Local 135 had more than 150 capsules. Haenam and Woogang had more than 75 grains per capsule. Since grain yield oflate planted sesame were significantly different among the varieties, breeding of sesame for after barly cropping would be more effective under late cultural condition of after barly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.201-207
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• 1993

This study was carried out to ascertain the flowering and boiling habits in conditions of vinyl mulched cultivation. The effects of vinyl mulching cultivation in cotton was early flowering. The flowering period was no more than 26 days and shedding of flower bud was lower. The total boll setting rate to flower number was about 38%. The number of flowering plants was rapidly increased until Aug. 8, then later was decreased, the period of the highest flowering occured was for 5 days from Aug. 6 to Aug. 10. Boll setting was increased that the flowers opened before July 30, then the later flowers was tended to decrease belling in spite of the increased flowering. However flower bud shedding had a tendency to decrease after the highest boiling period. The effect of weather, max. temperature and hours of sunshine on flowering days were highly positive significant correlation. Minimum temperatures, high air humidity and amount of rainfall had a negative significant correlation. The demanded days to flowering on the same internode in each fruiting branches was taken average 1.2 days, these days among the fruiting branches of the same internode was 3.6 days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.19-24
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• 1984

Experiment was conducted to know the interaction of temperature and solar radiation for spikelet formation of rice in different location. Under the Korea climatic conditions both number of spikelets and percentage of ripened grains affected yield of rice. Percentage of ripened grains was the most significant limiting factor in Tongil type rice varieties and the lower number of spikelets in japonica type varieties. The number of spikelets increased as amounts of solar radiation increased during the reproductive stage, as daily air temperature decreased from 23 to 28$^{\circ}C$, or as climatic consumption index (CCI) value decreased. CCI calculated with critical temperature of 1$0^{\circ}C$ and solar radiation was more closely correlated with the number of spikelets compared to CCI calculated with sunshine hours instead of solar radiation. CCI during the 15 days before heading was more closely related with the number of spikelets compared to CCI during the 30 days before heading.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.2
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• pp.311-318
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• 2015

Red tide occurs every year in the coastal seas of the South Korea, This phenomena has become a national issue of environmental and economic damage. In this study, we analyzed a suitable conditions to occur the red tide by using oceanic and atmospheric data during 10 years, These factors were applied to predict the red tide occurrence from 2012 to 2014. As a result, in 2012 and 2013, it is able to alarm the red tide occurrence before 6~11 days. However, in compared to the normal year and 2014, the prediction of red tide occurrence were less accurate because of more precipitation, short sunshine duration, low temperature waters. Therefore, it is necessary to further investigate the impact of sunshine duration(Solar radiation) on red tide occurrence, it is more necessary to consider the comprehensive analysis using additional oceanic and atmospheric factors.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.229-235
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• 1985

Zoning of the agroclimatic regions was attempted based on the distribution of drought index, effective temperature, meteorological factors and their standard deviation and a climatic productivity derived from yield response of rice to temperature and sunshine hours. The meteorological data obtained from synoptic weather stations under the Central Meteorology Office and simple weather observatories under the Rural Development Administration at 155 locations throughout the country were computerized in the PDP11/70, RDA Computer Center, to analyze the climatic similarities among the locations, except the Jeju Island. The nineteen different agroclimatic regions were classified, ego the Taebaeg Mountainous Region. the Charyung Southern Plain Region, etc., and the climatic characteristics of the regions were identified.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.97-102
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• 1987

The objective was to obtain the basic information for the changes of the alpha-acid content according to days after flowering. altitude and weather of Hoeongseong, Korea. The alpha-acid of hops reached the highest con-tent in sixty one days after flowering, and the optimum time for cone picking was noted as 11-15th August. The altitude for the highest alpha-acid content was 190-260m of Hoeongseong. The year-to-year variations in the alpha-acid content of hops were higher than the altitude variations. The higher alpha-acid content was associated with a higher temperature and more amounts of sunshine in late July. Alpha-acid content and yield had a significant positive correlation.

• Korean Journal of Environmental Agriculture
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• v.13 no.2
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• pp.160-167
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• 1994

Meteorological elements such as air temperature, relative humidity, rainfall, sunshine duration, and so on observed by Korea Meteorological Administration, were analyzed to estimate the climatic change and to establish countermeasures in agriculture. Climatic differences were compared between two periods, early($1931{\sim}1960$) and late($1961{\sim}1990$), by calculating climatic resource indices, coldness index and warmth index of the two periods. Annual mean air temperatures of Seoul, Taegu, and Pusan in 1910's were 10.7, 12.3, and $13.4^{\circ}C$, respectively, having increased by $1.3^{\circ}C$ in Seoul and Taegu and by $0.9^{\circ}C$ in Pusan in 1990's. Mean air temperature in the spring($March{\sim}May$) increased by $0.69^{\circ}C$, which is a higher increasing rate than in the other seasons ($0.26{\sim}0.33^{\circ}C$). Regional differences exist in annual mean air temperature between the early and late part of the 20th century with little increase in this experiment did not germinate at pH 1.0. At pH 2.0, the flowering cabbage and geranium in the middle northern area, while in the southern part about $1^{\circ}C$increase was recorded during the last period. In the late period the annual rainfall increased by 100mm, except for the western coast area and the middle northern area. The P/E ratio showed a trend of an annual increase in the late period, being higher in the summer and lower in the winter. Relative humidity showed slight differences in seasons and regions but annual values did not. Duration of sunshine decreased by about an hour in the spring. Coldness index and warmth index of the late period were higher by 3.7 and 1.0 than those of the early period, respectively.