• 한국작물학회지
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• 제42권3호
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• pp.352-356
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• 1997

우리 나라 농가포장에 현재까지 잡초성 벼인 앵미가 잔존하게된 경로를 추정하고자 앵미 발생이 극심한 농가포장을 선정하여 전체 개체에 대한 앵미 발생비율, 단위면적당 앵미 개체수, 이앙재배와 직파재배 포장에서의 앵미 발생 위치 등을 조사하여 다음과 같은 결과를 얻었다. 1. 이앙재배 포장에서 앵미 발생율이 가장 높았던 것은 5.5％였다. 2. 직파재배 포장의 앵미 발생이 이앙재배 포장보다 많았다. 3. 이앙재배 포장에서는 앵미가 대부분 재배벼 주내에 혼입되어 있었으나, 골뿌림 직파재배 포장에서는 골 사이에 발생한 앵미 개체가 많았다. 4. 비장려품종 재배 포장에서의 앵미 발생이 장려품종 재배 포장보다 많았다. 5. 이앙재배에서 앵미는 대부분 재배벼 종자에 혼입되어 잔존하였고, 극히 일부는 자연탈립에 의하였으며, 직파재배에서는 자연탈립에 의한 앵미 발생이 종자혼입에 의한 발생보다 많았다.

• 한국유기농업학회지
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• 제13권3호
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• pp.291-300
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• 2005

우리나라 벼 유기농업 실천농가의 가장 큰 애로사항은 알려져 있는 병해 및 잡초 제어기술을 정립하기 위하여 강화 등 5개 지역의 벼 유기농재배지와 관행재배지에서 병해충의 발생 실태를 조사한 결과는 다음과 같다. 1. 병해 발생조사결과 도열병은 관행재배지보다 오리농법 재배지에서 발병이 많았고 품종별로는 추청벼 보다 일품벼에서 발병이 많았으며, 잎집무의마름병은 오리농법과 쌀겨농법재배지에서 발병이 많았고 품종별로는 추청벼 보다 일품벼에서 발병이 많았으며, 문고병도 관행재배지보다 오리농법과 쌀겨농법에서 발병이 많은 경향이었다. 2. 친환경 자재의 벼 종자소독 효과시험 결과 현미식초 1,000배액이 키다리병 방제에 효과가 있었으며 발아율도 양호하였고, 시중에 종자소독용으로 유통되고 있는 친환경자재의 도열병에 대한 예방 및 치료효과는 미미하였다. 3. 헤어리벳치 재배구의 헤어리벳치 건물 중이 이앙시기에 추천량의 1/40에 불과하여 헤어리벳치 재배에 의한 토양물리성의 변화는 없었다. 4. 헤어리베치 잎과 뿌리의 추출물질은 상추종자의 발아 억제효과를 보였다.

• 한국유기농업학회지
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• 제9권3호
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• pp.45-71
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• 2001

The duck-rice forming system is increasingly spread up throughout Korea since 1992. It is discussed the rice field, rice quality, weed and pest management in the duck-rice weeding system compared to conventional farming system. Moreover the optimizing duck population, system management and fertilizer application rate were reported. Energy input and output by duck-rice farming system were carefully compared with those of low input sustainable paddy field and conventional farming paddy field. To find out the environmentally sound function of duck-rice system, the total nitrogen in paddy soil and paddy water, and nitrogen cycle in paddy rice cultivation system were analysed. finally the input and output were calculated, and ecological characteristic were determined in terms of nitrogen balance, labor input, animal input, renewable energy input, turnover of soil organic matter, energy loss, non-renewable indirect and direct energy input. It was concluded duck-rice weeding system could be recommended in terms of net only environmentally sound, but also farmer's income. But there are still some research needs for successful adaption of duck-rice farming to investigate to determine the optimal population of duck in rice paddy field unit, release time of duckling, duck management after release, and strategy for duck marketing and duck processing.

• Animal cells and systems
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• 제8권4호
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• pp.281-288
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• 2004

The change in relationships between methane production and sulfate reduction was investigated in reclaimed rice field soils at different time points after reclamation of tidal flat in Korea. Sulfate concentrations of soils in the ca. 60-year-old and 26-year-old reclaimed rice fields were much lower than that in a natural tidal flat. During 60 d of anaerobic incubation, total methane production and sulfate consumption of the soil slurries were 7.0 ${\mu}$mol $CH_4$/g and 8.2 ${\mu}$mol $SO_4^{2-}$/g in the 60-year-old rice field, 5.6 ${\mu}$mol $CH_4$/g and 12.7 mmol $SO_4^{2-}$/g in the 26-year-old rice field, and ca. 0 mmol $CH_4$/g and 22.4 ${\mu}$mol $SO_4^{2-}$/g in a natural tidal flat. Relative percent electron flow through sulfate reduction in the 60-year-old rice field was much lower (50.8%) compared with the 26-year-old rice field (69.3%) and the tidal flat (99.9%). The addition of an inhibitor of methanogenesis (2-bromoethanesulfonate) had no effect on sulfate reduction in the soil slurries of the reclaimed rice fields. However, instant stimulation of methane production was achieved with addition of an inhibitor of sulfate reduction (molybdate) in the soil slurries from the 26-year-old reclaimed rice field. The specific inhibitor experiments suggest that the relationship of methanogenesis and sulfate reduction might become mutually exclusive or syntrophic depending on sulfate content in the soil after reclamation. Sulfate, thus sulfate reduction activity of sulfate-reducing bacteria, would be an important environmental factor that inhibits methane production and determines the major pathway of electron and carbon flow in anaerobic carbon mineralization of reclaimed rice field soils.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.468-473
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• 1999

This study was carried out to assess the use of RADARSAT data which is C-band with HH polarization for the rice growth monitoring in Korea. Nine time-series data were taken by shallow incidence angle (standard beam mode 5 or 6) during rice growing season. And then, backscatter coefficient ($\sigma$$^{\circ}$) were extracted by calibration process for comparing with rice growth parameters such as plant height leaf area index(LAI), and fresh and dry biomass. Field experimental data concerned with rice growth were collected 8 times for the ground truth at the study area, Tangjin, Chungnam, Korea. At the maximum vegetative stage of rice, backscatter coefficients were the highest at the flooded rice field ranging from -4.4dB~-3.1dB. The temporal variation of backscatter coefficient($\sigma$$^{\circ}$) in rice field was significant in this study Backscatter coefficient ($\sigma$$^{\circ}$) of rice field was a little bit lower again after heading stage. This results show RADARSTA data is promising for rice monitoring.

• 한국작물학회지
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• 제45권4호
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• pp.232-236
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• 2000

To obtain a basic information on the development of effective control strategies for weedy rice in direct seeding rice cultivation, occurrence patterns of weedy rice as influenced by different cultural practices such as cultivation method, water management, seeding time, and tillage were investigated in field or pot experiments. High occurrence of weedy rice was observed in a continuous direct seeding paddy field as compared to machine transplanted one. Based on the percent of weedy rice panicle over three years trial, high ridged dry seeding was highest with 36.9%, followed by wet seeding with 30.9%, water seeding with 14.6% and machine transplanting rice with 0.8%, indicating 97.8% reduction in weedy rice occurrence by machine transplanting rice as compared with high ridged dry seeding. Germination of weedy rice was promoted to 83-94 % when rice panicle was flooded from September 30 to October 10 for 6 days and 74-88% for 9 days on October 20. Weedy rice occurrence was also substantially reduced by delayed seeding on June 10 and intensive tillage. The results suggest that machine transplanting rice be more effective cultural practice than flooding treatment, delayed seeding and intensive tillage when weedy rice problem occurs in direct seeded paddy field.

• 한국작물학회지
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• 제35권4호
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• pp.370-374
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• 1990

벼물바구미 피해정도에 따른 벼 생육 및 미질 변화에 미친 영향을 조사한 결과는 다음과 같다. 1. 벼물바구미 피해정도에 따라서 보면 피해정도가 심할수록 경수는 적고, 초장은 짧았으며 최고분벽기도 지연되었다. 2. 벼물바구미 피해에 의하여 출수기는 1-2일 정도 지연되었고, 간장도 짧아졌으며, 수수도 감소하였고, 등숙율은 떨어지는 경향이었다. 3. 벼물바구미 피해에 의하여 수량은 4-22% 감소하였으며, 그 정도는 1모작보다 2모작에서 심하였다. 4. 벼물바구미 피해에 의한 미질 변화는 불완전미가 증가하였고, 특히 청미가 증가하였다.

• 한국유기농업학회지
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• 제13권3호
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• pp.301-314
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• 2005

우리나라 벼 유기농업 실천농가의 가장 큰 애로사항은 알려져 있는 병해충의 제어기술을 정립하기 위하여 강화 등 5개 지역의 벼 유기농재배지와 관행재배지에서 해충의 발생실태와 방제실태를 조사한 결과는 다음과 같다. 1. 벼 생육시기별 해충발생은 강화지역의 오리농법과 쌀겨농법 재배지에서 본답 중기에 애멸구의 밀도가 높았으며 여주지역의 관행재배지에서 본답초기에 벼물바구미의 밀도가 높았다. 홍성지역에서는 본답초기에 관행방제구에 비하여 유기재배지에서 끝동매미충과 벼물바구미의 밀도가 높았다. 시기별 해충발생은 본답후기에 많았으며 지역 간의 차이는 있었으나 유기재배지에서 많은 경향이었다. 2. 홍성지역에서는 오리투입시기에는 발생이 적었으나 본답초기 및 후기에 발생이 많았다. 천적류도 본답후기에 발생이 많았고 지역별로 큰 차이는 없었으며 거미류와 기생봉류가 주류를 이루었다. 홍성지역에서는 유기재배지보다 관행재배지에서 꼬마거미와 접시거미의 발생이 많았다. 논거미의 분포는 대부분 조망성 거미인 꼬마거미과, 접시거미과, 갈거미과 등이 배회성 거미인 늑대거미, 염낭거미, 닷거미 등 보다 다양한 지역에서 발생하였으며, 거미의 발생량은 지역간의 차이가 심하였고 농법간의 차이는 일관성이 없었다. 3. 일부 자재의 경우 방제효과가 높이 나타났으나, 유기농 자재에 대한 효과는 보다 과학적인 검증이 필요한 상태이다.

• 대한원격탐사학회지
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• 제16권2호
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• pp.109-116
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• 2000

This study was carried out to assess the use of RADARSAT data which is C-band with HH polarization for the rice growth monitoring in Korea. Nine time-series data were taken by shallow incidence angle (standard beam mode 5 or 6) during rice growing season. And then, backscattering coefficients ($\sigma$$^{\circ}$) were extracted by calibration process for comparing with rice growth parameters such as plant height, leaf area index(LAI), and fresh and dry biomass. Field experimental data concerned with rice growth were collected 8 times for the ground truth at the study area, Tangjin, Chungnam, Korea. At the beginning of rice growth, backscattering coefficients were ranged from -l6~-l3dB when rice fields were not covered with rice canopy and flooded. At the maximum vegetative stage of rice, backscattering coefficients of the rice field were the highest ranging from -4.4dB~-3.1dB. The temporal variation of backscattering coefficient($\sigma$$^{\circ}$) in rice field was significant in this study. Backscattering coefficient ($\sigma$$^{\circ}$) of rice field was a little bit lower again after heading stage than before. This results show RADARSAT data is promising for rice monitoring.

• Journal of Biosystems Engineering
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• 제31권1호
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• pp.59-64
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• 2006

Application of herbicide for rice cropping is inevitable but notorious for its side effect of environmental pollution. Precision fanning will be one of important tools for the least input and sustainable fanning and could be achieved by implementation of the variable rating technology. If a device to detect weeds in rice field is available, herbicide could be applied only to the places where it is needed by the manner of the variable rating technology. The study was carried out to develop an algorithm of image processing to detect weeds in rice field using a machine vision system of multi-spectral digital images. A series of multi-spectral rice field picture of 560, 680 and 800 nm of center wavelengths were acquired from the 27th day to the 39th day after transplanting in the ineffective tillering stage of a rice growing period. A discrimination model to distinguish pixels of weeds from those of rice plant and weed image was developed. The model was proved as having accuracies of 83.6% and 58.9% for identifying the rice plant and the weed, respectively. The model was used in the algorithm to differentiate weed images from mingled images of rice plant and weed in a frame of rice field picture. The developed algorithm was tested with the acquired rice field pictures and resulted that 82.7%, 11.9% and 5.4% of weeds in the pictures were noted as the correctly detected, the undetected and the misclassified as rice, respectively, and 81.9% and 18.0% of rice plants in the pictures were marked as the correctly detected and the misclassified as weed, respectively.