• 한국농공학회논문집
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• 제60권3호
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• pp.107-112
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• 2018

In this study, we conducted to analyze and quantify the amount of nitrogen supply into the rice paddies from the rainfall during cropping and non-crop periods. Rainfall monitoring conducted 85 times from June 2015 to December 2017. Nitrogen supply of cropping season ranged from 5.37 to 7.70 kg/ha, while non-cropping season were supplied from 3.97 to 4.42 kg/ha. The supply of T-N in the crop period was more than 60% of the total supply. And as a result of analyzing the correlation between the characteristics of rainfall and the supply amount, nitrogen concentrations in rainfall were decreased with increasing rainfall, but the supply amount was increased. Therefore, efforts should be made to increase the rainfall utilization and to increase the nitrogen supply of crops by increasing rainfall storage through drainage management.

• 한국초지조사료학회지
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• 제20권3호
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• pp.147-154
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• 2000

This study was conducted to increase the utility and productivity of forage crops at high altitued areas. For that purpose, 21 cultivars of corn and 2 cultivars of rye were cultivated for 3 years using a randomized block designed with 3 replications. The results obtained were as follows. 1. In the Taekwallyong area (800m above sea level) which has a short frostless period, all the seeding and harvest of corn must be finished within about 135 days between mid May, the time of the last frost, and late September, the time of the first frost 2. It was relatively safe for the early maturity cultivar(ll0days) and the medium maturity cultivar(l20days), compared to the late maturity cultivar(l30days) which might have had the possibility of an overlapping period between the time of harvest and the first frost in high altitude areas 3. The productivity of forage corn, which is the most efficient crop for capturing solar energy, varied significantly with the climate circumstances but the productivity of Taekwallyong showed similar results of 19 M/T/ha, compared with 20 M/T/ha in Suwon from the '96-'98 study 4. Rye could be cultivated in high altitude areas and when corn was raised as a second crop after rye in the same year, it was possible to increase the productivity of dry matter yield by 20% through double cropping(P < 0.05). (Key words : Cropping system, Corn, Rye, Forage production)

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2011년도 학술발표회
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• pp.16-18
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• 2011

Evaluation of climate change on the rice productivity was conducted using crop growth simulation model, where Odae, Hwaseong, Ilpum were used as a representative cultivar of early, medium, and medium-late rice maturity type, respectively, and climate change scenario 'A1B' was applied to weather data for future climate change at 57sites. When cropping season was fixed, rice yield decreased by 4~35% as climate change which was caused by poor filled grain ratio with high temperature and low irradiation during grain-filling. When cropping season was changed, rice yield decreased by only 0~5% as climate change which was caused poor filled grain ratio with low irradiation during grain-filling period. However, this irradiation decline was less than when cropping season was fixed. Therefore, we need to develop rice cultivars resistant to low irradiation which can maintain high filled grain ratio under poor irradiation condition, and late maturity rice cultivars whose growing period is longer than the present medium-late maturity type.

• 한국농공학회논문집
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• 제56권2호
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• pp.37-46
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• 2014

Water for crop growth were supplied by irrigation in protected cultivation and these are accumulated in the soil and utilized for crop evapotranspiration. The study for analyzing soil moisture characteristics is necessary for adequate irrigation water and soil water management in protected cultivation. Soil moisture content, irrigation water quantity and meteorological data were monitored to analyze soil moisture increment and extraction characteristics in terms of soil layers and cucumber crop growth stages. In first cropping period, the total amount of irrigation water was 5.07 mm/day, soil moisture increment was 4.82 mm/day and soil moisture extraction was 5.56 mm/day. In second cropping period, the total amount of irrigation water was 4.82 mm/day, soil moisture increment was 4.65 mm/day and soil moisture extraction was 4.73 mm/day. Soil moisture extraction rate from 0 to 75 cm is 90.3 % in first cropping period and 79.1 % in second cropping period. The majority irrigation water were consumed in root zone, however, about 15 % of soil moisture were losses by infiltration in lower soil layer. Soil moisture extraction and extraction pattern of cucumber crop calculated in this study can be utilized as a basic data for irrigation water management in protected cultivation.

• 농촌계획
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• 제8권1호
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• pp.69-76
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• 2002

A study was carried out to investigate the losses of sediment at a paddy plot located at the southern Korea. The observed amount of precipitation, irrigation, runoff fer the experimental paddy plot during the cropping period were 1,030, 566, and 701 mm in 1999 and 1,214, 413, and 710 mm in 2000, respectively. The observed sediment losses from the plot during cropping period were 1,221.3 kg $ha^{-1}$ in 1999 and 1,274 kg/ha kg $ha^{-1}$ in 2000, respectively.

• 농촌계획
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• 제8권1호
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• pp.15-25
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• 2002

The study was carried out to investigate the water balance and losses of nutrients from paddy fields during cropping period. The size of paddy fields was 95 ha and the fields were irrigated from a pumping station. The runoff loading was the highest in June because of the high concentrations of nutrients due to applied fertilizer, When the runoff Bosses of nutrients were compared to applied chemical fertilizer, it was found that 39.1 % to 42.5 % of nitrogen lost via runoff while runoff losses of phosphorus account for 14.5 % to 17 % of the total applied amount during cropping period. When the ratio was calculated between nutrients losses by infiltration and the applied of chemical fertilizer, two year results showed 9.1% to 10.8% for nitrogen and 0.5% for phosphorus, respectively.

• 한국농림기상학회지
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• 제2권3호
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• pp.95-102
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• 2000

근래의 '춥지 않은 겨울'현상의 연속출현으로 가을 보리의 재배지역의 북상에 따른 재배면적 확대를 논의 할 만하다. 최근('74∼'98년)의 가을보리재배기간(10∼5월)의 기상변화를 살펴보고 '87년을 기준으로 '춥지 않은 겨울현상'을 보인 13년('87∼'99년) 그전 13년('74∼'86년)의 가을보리 재배기간의 기상을 평년('61∼'90년)기상과 비교ㆍ분석한 결과는 다음과 같다. 1. 최근 25년 동안 가을보리재배기간의 평균기온은 1.02℃ 증가하였으며, 평균기온의 상승은 최저기온보다 최고기온의 상승이 더 크게 기여하였다. 2. 가을보리재배기간의 연도별 강수량은 최근 25년 동안 전국평균이 513.3 ㎜ 이었으며.'74년 이후 감소하다가 '92년 이후로는 다시 증가하는 경향이었으며, 일조시간은 농촌지역만 조금 적어지는 경향이고 다른 지역들은 조금씩 증가하는 경향을 보였다. 3. '춥지 않은 겨울' 현상을 보인 최근 13년의 가을보리재배기간의 기온은 평년보다 높았으며 특히 1∼2월의 기온이 많이 상승하였다 반면에 '87년을 기준으로 그전 13년의 기온은 평년과 비슷하거나 다소 낮은 경향을 보였다. 4. '춥지 않은 겨울'현상을 보인 최근 13년의 가을 보리재배기간의 강수량은 평년과 전반적으로 비슷하였으나, 4월의 강수량이 전국적으로 평년보다 26㎜정도 적었다. 반면에 일조시간은 전반적으로 평년보다 적었다 그러나, '87년을 기준으로 그전 13년의 강수량과 일조시간은 대체로 평년과 비슷하였다. 5. 가을보리의 안전재배선의 기준이 되는 월동기(1∼2월)의 기온상승으로 가을보리안전재배의 북상이 전망된다.

• 한국환경과학회지
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• 제30권8호
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• pp.659-671
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• 2021

The physicochemical properties of soil and the yield and quality of rice (Oryza sativa L. cv. Sailmi) were assessed using Italian ryegrass (Lolium multiflorum Lam. cv. Kowinearly)-rice double cropping systems in the paddy fields at Goseong and Miryang in southern Korea. The average temperatures during the ripening period were approximately 1 ℃ higher than the optimal temperature for rice ripening and the sunshine duration was reduced by frequent rainfall. Consequently, it was slightly below the optimal conditions required for rice ripening. In the soil at Goseong, winter Italian ryegrass cropping increased the pH, electrical conductivity, and the contents of organic matter, total nitrogen (T-N), available P₂O₅, K, Ca, and Mg than winter fallowing. Particularly, the contents of T-N and available P₂O₅increased significantly. In the soil at Miryang, Italian ryegrass slightly increased the electrical conductivity and the T-N, Mg, and Na contents. Therefore, winter Italian ryegrass cropping improved the physicochemical properties of paddy soils; however, Italian ryegrass-rice double cropping slightly reduced the culm length at both Goseong and Miryang, without markedly changing the panicle length or number compared to fallow-rice cropping. Furthermore, at Goseong, Italian ryegrass-rice double cropping slightly decreased the spikelet number and milled rice yield, and increased the ripened grain rate; however, at Miryang, contrasting results were observed. In addition, fallow-rice cropping revealed no differences in the head rice or opaque rice rates. The protein content was slightly increased in Italian ryegrass-rice double cropping, without significant changes in the amylose content or Toyo value, compared to that in fallow-rice cropping. The peak and breakdown viscosities were slightly decreased. These results indicate that winter Italian ryegrass cropping might alter rice taste but may not exhibit remarkable negative effects on rice cultivation. Therefore, Italian ryegrass-rice double cropping system is recommended for paddy fields in southern Korea. Nevertheless, to increase the rice yield and quality, fertilization standards for rice cropping that consider the changes in the T-N and organic matter contents in paddy fields caused by winter Italian ryegrass cropping need to be established.

• 한국기후변화학회지
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• 제6권3호
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• pp.203-208
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• 2015

This study was conducted to provide the agricultural climatological basic data for the reset of sowing period of the winter crop on the double cropping system with rice. During the past 30 years from 1981 to 2010, mean air temperature has risen by $0.45^{\circ}C$ per 10 years (with statistical significance), while precipitation has decreased by 6.74 mm per 10 years and the numbers of days for precipitation has reduced by 0.23 days per 10 years (with no statistical significance) in the sowing period ($1^{st}$ Oct. to $5^{th}$ Nov.) of winter crop. It was analyzed that double cropping system of rice and winter crops need to be reset in the way of delaying the sowing time of winter crops, because rising trend of temperature was clear while variability of precipitation was great and the trend was not clear in the sowing period of winter crops. We have also analyzed the meteorological features of the sowing period of winter crops in 2014, and found that mean air temperature in 2014 was higher than that in normal years (similar to recent temperature change feature) while precipitation in 2014 was much more frequent than that in normal years (unlike recent precipitation features). Such tendency in 2014 made the sowing of winter crops difficult because mechanical sowing could not be worked in flooded paddy fields. Heavy rain in October 2014 was also analyzed as a rare phenomenon.

• 한국미생물·생명공학회지
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• 제7권1호
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• pp.37-46
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• 1979

나왕과 소나무배지에서 느타리버섯 재배기간 중 배지의 성분변화를 파악하기 위하여 종균접종시부터 수확이 끝나는 폐상시까지의 두 가지 배지와 버섯의 여러가지 성분을 분석하여 다음과 같은 결과를 얻었다. 1) 느타리버섯의 전체수량은 나왕배지에서 6.39kg/$m^2$, 소나무배지에서 6.31kg/$m^2$이었고, 양배지 모두 94% 1, 2주기에서 얻어졌다. 2) 재배기간중 양배지의 회분량은 증가 되었으나 유기물은 감소되었으며 수분은 종균접종시 약 79%이던 것이 균사번식기간 중에 다소 감소되었고 그 이후부터는 큰 변화가 없었다. 3) 두 가지 배지의 전질소는 점차적으로 감소되었고 불용성질소의 절대감소량은 수용성 질소보다 컸으며 아미노태 질소는 계속 증가의 추세를 보이었다. 4) 두 가지 배지에서 pentosan, $\alpha$-cellulose, lig-nin 및 C/N율은 점차적으로 감소되었고 환원당, trehalose, mannitol은 계속 증가의 추세를 보이었다. 5) 두 가지 배지에서 P, K, Mn, Zn은 감소되었고, Mg, Ca, Fe, Cu는 불규칙하게 변화되었다. 6) 재배기간중 CMC 당화활성과 CMC 액화활성은 균사번식후부터 2주기 수확까지는 두 가지 배지에서 점차적으로 증가되었으나 그 이후부터는 감소되었다. Xylanase활성은 1주기보다 2주기에서 급격히 상승되었고 3주기부터는 서서히 감소되었으며, protease 활성은 균사번식 후 최고의 활성도를 보였다가 점차로 감소하였다. 또한 배지의 pH는 재배기간에 걸쳐 다소 감소되었다. 7) 두 가지 배지에서 버섯의 각 주기별 성분변화는 1~3주기까지는 거의 비슷하였으나 4주기에서는 다소 감소의 추세를 보였다.