• 한국토양비료학회지
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• 제44권3호
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• pp.408-414
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• 2011

유기농 벼 재배에 유리한 지역을 찾고자 재배지역을 산간, 일반농촌 및 도시근교로 달리하여 재배하였을 때 병해충 및 잡초발생량, 벼의 생육과 쌀의 품질을 조사하였다. 재배지역에 상관없이 유기와 관행재배 모든 처리구에서 잎집무늬마름병, 도열병, 혹명나방 및 벼멸구가 발생되었다. 유기재배의 지역별 멸구류 발생 밀도는 20주당 4.4~10 마리이었지만, 관행재배에서는 10.1~19.5 마리로 유기재배보다 높았다. 유기와 관행재배 벼논에서 우점적으로 발생한 잡초는 1년생 잡초인 물달개비 (Monochoria vaginalis)와 여뀌바늘 (Ludwigia prostrata), 다년생 잡초인 알방동사니 (Cyperus difformis)이었다. 지역별로 가장 많은 잡초발생 지역은 도시근교로 유기와 관행재배에서 발생한 잡초의 밀도는 각각 $m^2$ 당 121, 79.2본 이었으며 잡초의 건물중은 각각 $m^2$ 당 50.5, 11.4 g 이었다. 벼 재배지역별 수량은 산간지역이 $2.96Mg\;ha^{-1}$으로 낮았으며 수량이 높은 처리구는 일반농촌과 도시근교의 관행 재배로서 각각 4.56, $4.31Mg\;ha^{-1}$ 이었다. Toyo 식미치는 벼 재배지역별 유의성은 없었으나 영농방법에 의한 유의성은 있는 것으로 나타났다. 산간과 도시근교의 유기농 재배에서의 식미치는 관행재배보다 높았다. 벼 재배지역별 완전립의 비율은 유기재배와 관행재배에서 차이가 없는 것으로 나타났다. 불완전립 비율 또한 재배지역에 따른 유의성은 나타나지 않았고, 불완전립의 비율은 27.2~33.1%이었으며, 이중에서 가장 큰 비율을 차지하는 것은 미숙립과 피해립이었다.

• 한국토양비료학회지
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• 제43권6호
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• pp.1047-1050
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• 2010

본 연구는 논토양 비옥도에 대한 예취높이별 볏짚 혼입효과를 구명하고자 수행하였다. 예취높이별 잔존량은 1,420 kg $ha^{-1}$ (10 cm), 1,850 kg $ha^{-1}$ (15 cm), 2,400 kg $ha^{-1}$ (20 cm)를 나타냈다. 볏짚 혼입으로 토양경도, 용적밀도는 낮아졌고 공극률이 증가하여 토양물리성이 개선되었다. 볏짚 수거로 토양유기물, 유효인산 및 유효규산 함량이 적어지고 양이온치환용량이 낮아졌다. 토양에 볏짚 혼입시 비옥도 감소 폭이 적었고 예취높이별 잔존량이 많을수록 혼입효과가 크게 나타났다. 볏짚혼입에 따라 수수, 영화수 확보가 많고 등숙비율이 높아졌으며 쌀수량은 관행 (3.67 Mg $ha^{-1}$)대비 28~32% 증수되었다. 연구결과 예취방법에 의하여 볏짚을 혼입한 재배기술이 수거에 비하여 쌀수량을 증가시켰고 논토양을 개선하였다.

• 농업과학연구
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• 제41권2호
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• pp.113-117
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• 2014

This study was conducted to evaluate the efficacy of benzobicyclon mixtures by using Remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field. Eight annual weed species including Echinochloa crus-galli L. and three perennial weeds were dominated in the experimental field. Application of benzobicyclon mixtures using RCAA was highly effective to control both annual and perennial weed species. When compared with untreated control, no visual injuries were detected at single and double dosage of benzobicyclon mixtures. Finally, rice yield in the benzobicyclon mixtures was as much as that in the hand weeding. This study indicates that benzobicyclon mixtures using RCAA can be applied to control both annual and perennial weed species in rice paddy field.

• 한국농공학회논문집
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• 제54권4호
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• pp.65-71
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• 2012

The objective of this study was to estimate surface runoff from rice paddy plots using an artificial neural network (ANN). A field experiment with three treatment levels was conducted in the NICS saemangum experimental field located in Iksan, Korea. The ANN model with the optimal network architectures, named Paddy1901 with 19 input nodes, 1 hidden layer with 16 neurons nodes, and 1 output node, was adopted to predict surface runoff from the plots. The model consisted of 7 parameters of precipitation, irrigation rate, ponding depth, average temperature, relative humidity, wind speed, and solar radiation on the daily basis. Daily runoff, as the target simulation value, was computed using a water balance equation. The field data collected in 2011 were used for training and validation of the model. The model was trained based on the error back propagation algorithm with sigmoid activation function. Simulation results for the independent training and testing data series showed that the model can perform well in simulating surface runoff from the study plots. The developed model has a main advantage that there is no requirement for any prior assumptions regarding the processes involved. ANN model thus can be a good tool to predict surface runoff from rice paddy fields.

• 대한원격탐사학회지
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• 제28권6호
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• pp.653-660
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• 2012

This study classified paddy fields according to rice varieties and monitored temporal changes in rice growth using SAR backscatter coefficients (${\sigma}^{\circ}$). A growing period time-series of backscatter coefficients was set up for nine fine-beam mode RADARSAT-1 SAR images from April to October 2005. The images were compared with field-measured rice growth parameters such as leaf area index (LAI), plant height, fresh and dry biomass, and water content in grain and plants for 45 parcels in Dangjin-gun, Chungnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) ranged from -18.17 dB to -6.06 dB and were lower than those for medium-late maturing rice varieties during most of the growing season. Both crops showed the highest backscatter coefficient values at the heading stage (late July) for early-maturing rice, and the difference was greatest before harvest for early-maturing rice. The temporal difference in backscatter coefficients between rice varieties may play a key role in identifying early-maturing rice fields. On the other hand, comparisons with field-measured parameters of rice growth showed that backscatter coefficients decreased or remained on a plateau after the heading stage, even though the growth of the rice canopy had advanced.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.243-245
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• 2007

This study was begun to classify the paddy fields by the rice varieties and to monitor the temporal change in rice growth using SAR backscatter coefficients $({\sigma}^{circ})$. For nine fine-beam mode images of Radarsat-1 SAR, a growing period time-series of backscatter coefficients was set up from April to October in 2005, and was compared with the field-measured rice growth parameters such as LAI (leaf area index), plant height, fresh and dry biomass, and water content in grain and plant for 45 parcels in Dangjin-gun, Chungcheongnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) were ranged from -18.17dB to -6.06dB and were lower than for medium-late maturing rice varieties during most of the growing season. At around the heading stage (July 30) for early-maturing rice, both rice crops showed the highest backscatter coefficient values and the difference was the greatest before harvesting early-maturing rice. The temporal difference in backscatter coefficients between rice varieties was expected to play a key role to identify early-maturing rice fields. On the other hand, comparison with field-measured rice growth parameters showed that the backscatter coefficients decreased or stayed on the plateau after heading stage even though the growth of rice canopy advanced.

• 한국관개배수논문집
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• 제2권2호
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• pp.20-26
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• 1995

A three year project was carried out to determine the discharge of major nutrients from the agricultural land to the catchment basin during rice-season, i.e. May to October. The catchment area was 96.2ha, which was consisted of 12.5 ha for the paddy rice

• 한국작물학회지
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• 제27권3호
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• pp.223-228
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• 1982

간탁답에서 생육한 수도의 근군형성과 물관리와의 관계를 조사하기 위하여 상이한 물관리를 한 간탁답과 상시담수를 한 숙답에서 생육한 수도의 근군을 채취하여 비교ㆍ검토한 결과를 요약하면 다음과 같다. 1. 간탁지상시담수구와 간탁지 2일환수구에서 생육한 수도의 근군은 작토의 표층부에 분포되어 있었나, 간탁지암거배수구와 숙답상시담수구에서 생육한 수도의 근군은 작토의 심층부까지 균일하게 분포되어 있었다. 2. 간탁지상시담수구와 간탁지 2일환수구에서 생육한 수도의 근군은 간탁지암거배수구나 숙답상시담수구에서 생육한 수도의 근군보다 관근수가 적었다. 3. 재배지나 물관리에 관계없이 유수형성기 이후에 발근하는 요소에서는 생장중지형 관근의 비율이 생육 초 중기의 그것보다 높았다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.319-319
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• 2017

Methane is the main greenhouse gas released from rice paddy field. Methane from paddy fields accounts for 11 % of the global total methane emission. The global warming potential (GWP) of methane is 25 times more than that of carbon dioxide on a mass basis. It is well known that most effective practice to mitigate methane in paddy is related to the water management during rice growing season and the use of organic matters. This study was conducted to investigate the effects of tillage and cultivation method on methane emission in paddy. Tillage (tillage and no-tillage) and cultivation methods (transplanting and direct seeding) were combined tillage-transplanting (T-T), tillage-wet hill seeding (T-W), tillage-dry seeding (T-D) and no-till dry seeding (NT-D) to evaluate methane mitigation efficiency. Daily methane emission was decreased on seeding treatments (T-W, T-D, NT-D) than transplanting treatment (T-T). Amount of methane emission during rice growing season is highest in T-T ($411.7CH_4\;kg\;ha^{-1}y^{-1}$) and lowest in NT-D treatment (89.7). In T-W and T-D treatments, methane emissions were significantly decreased by 36 and 51 % respectively compared with T-T. Methane emissions were highly correlated with the dry weight of whole rice plant ($R^2=0.62{\sim}0.93$). T-T treatment showed highest $R^2$ (0.93) among the four treatments. Rice grain yields did not significantly differ with the tillage and cultivation methods used. These results suggest that direct seeding practice in rice production could mitigate the methane emissions without loss in grain yield.

• 한국작물학회지
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• 제46권2호
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• pp.84-88
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• 2001

Two methods of nitrogen application at the 4th leaf stage were evaluated in direct-seeding rice cultivation on dry paddy soil: one was the top dressing of nitrogen on dry paddy condition before irrigation (TNDP) for labor saving, and the other was the top dressing of nitrogen on dry paddy with mechanical rotavation of the inter-row space (TNDPIR) for increasing the efficiency of nitrogen. To evaluate these two application methods, leaf chlorophyll contents, growth characteristics and yields were compared with two conventional methods, basal application (BA) and top dressing on flooded paddy condition at the 4th leaf stage (TNFP). The SPAD value of rice in TNDP was similar with that in TNFP throughout the whole growth stage of rice. Also, there were no differences in rice growth and yield between the two methods. However, in TNDPIR, the SPAD value was the highest during tillering stage among the four application methods, and the tiller number, LAI at heading stage and the panicle number were higher than the two conventional methods.