• 한국대기환경학회지
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• 제17권2호
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• pp.203-212
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• 2001

During the growing season from June to August, 2000, the soil NO and $N_2$O fluxes were measured to elucidate characteristics of soil nitrogen emissions from different types of intensively managed agricultural soils at outskirts of Kunsan City, located in the western inland of Korea, Flux measurements were made using a closed chamber technique at two different agricultural fields; one was made from upland field, and the other from rice paddy field. The flux data from upland field were collected for both the green onion and soybean field. Concentrations of NO and $N_2$O inside a flux chamber ar 15 minute sampling interval were measured to determine their soil emissions. Either polyethylene syringes of teflon air bags were used for gas samples of $N_2$O and NO. The analysis of NO and $N_2$O was made using a chemiluminesence NO analyzer and GC-ECD, respectively no later than few hours after sample collection at laboratory. The gas fluxes were varied more than one standard deviation around their means. Relatively high soil gas emissions occurred in the aftermoon for both NO and $N_2$O. A sub-peak for $N_2$O emission was observed in the morning period, but not in the case of NO. NO emissions from rice paddy field were much less than those from upland site. It seems that water layer over the rice paddy field prevents gases from escaping from the soil surface covered with were during the irrigation and acts as a sink of these gases. The NO fluxes resulted from these field experiments were compared to those from grass soil and they were found to be much higher. Diurnal and daily variations of NO and $N_2$O emission were discussed and correlated with the effects of nitrogen fertilizer application on the increase of the level of soil nitrogen availability.

• 한국환경농학회지
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• 제28권1호
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• pp.53-58
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• 2009

The propose of this study was to find out optimum conditions for no-tillage rice-winter cover crops cropping system. A field research was conducted to evaluate productivity and quality of rice cultivars (Dongjinbyeo and Junambybyeo) in rice-winter cover cropping systems at Doo-ryangmyeon., Sacheon, Gyeongsangnam-do, Korea from January 2005 to October 2006. The experimental soil was Juggog series (fine silty, mesic family of Fluvaquentic Eutrndepts). The rice cultivars were experimented under some different high residue farming systems, i.e. no-tillage no treatment (NTNT), no-tillage amended with rice straw (NTRS), no-tillage amended with rye (NTR), no-tillage amended with Chinese milkvetch (NTCMV), tillage no treatment (TNT), and conventional cropping system (Control). The miss-planted rate was 8.8% in 2005 and range of 10.8% to 13.3% in 2006 at NTR, and the other treatments were carried out at miss-planted rate ranging from 1.2% to 5.0%. Tiller numbers of Junambyeo, and Dongjinbyeo in both of years were the highest in Control, and decreased nearly in NTCMV, NTR, NTRS, NTNT, and TNT in that order. The lowest grain yield was observed in TNT both cultivars due to the lower tiller numbers per area, and spikelet numbers per panicle. Also, no-tillage treatments were lower grain yield than control. On the other hand, 1,000-grain weight was lowest in control due to higher tiller numbers per area, and spikelet numbers per panicle. Ripened grain ratio was a similar aspect in all treatments. The palatability score of milled rice was lowest in control while protein content of milled rice was highest in control. The NTCMV was considered an effective sustainable farming practice for rice yield and quality.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.240-246
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• 2006

Cyanobacteria are present abundantly in rice fields and are important in helping to maintain rice fields fertility through nitrogen fixation. Many rice fields soil contain a high density of cyanobactera, and over 50% of cyanobacterial genera that are in existence in rice paddy fields are heterocystous filamentous forms. A total of 142 isolates of heterocystous filamentous cyanobacteria were screened from 100 soil samples taken from rice paddy fields in 10 different locations across Korea, classified according to their morphological characteristics under light microscopy, and their susceptibly to fungicides examined. The collected blue-green alga were classified into a total of 14 genera, including seven genera of filamentous cyanobacteria and seven genera of nonfilamentous cyanobacteria. In particular, 142 heterocystous filamentous cyanobacteria were isolated and classified into six genera, including Anabaena, Nostoc, Calothrix, Cylindrospermum, Nodularia, Scytomena, and Tolypotrix. Yet, over 90% of the heterocystous filamentous cyanobacteria isolated from the rice paddy fields belonged to two genera: Anabaena and Nostoc. The response of 129 $N_2-fixing$ cyanobacterial isolates, 53 Anabaena and 76 Nostoc, to 10 fungicides was then investigated. The results showed that the Nostoc spp. were more tolerant of the ten tested fungicides than the Anabaena spp., and among the ten tested fungicides, benomyl showed the highest acute toxicity to Anabaena spp. and Nostoc spp. In conclusion, although benomyl is a very useful agent to control phytopathogenic fungi, the application of this fungicide to rice fields should be considered because of its toxicity to the heterocystous filamentous cyanobacteria.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.633-636
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• 2007

The objective of this study is to measure backscattering coefficients of paddy rice using L, C, X-bands scatterometer system during a rice growth period. The measurement was conducted at an experimental field located in National Institute of Agricultural Science and Technology (NIAST), Suwon, Korea. The rice cultivar was a kind of Japonica type, called Chuchung. The scatterometer system consists of dual-polarimetric square horn antennas, HP8720D vector network analyzer (20MHz ${\sim}$ 20GHz), RF cables, and a personal computer that controls frequency, polarization and data storage. The scatterometer system is calibrated using a calibration kit (3.5mm, 85052D). The backscattering coefficients were calculated by applying radar equation for the measured at incidence angles between $20^{\circ}$ and $60^{\circ}$ for four polarization (HR, VV, HV, VH), respectively, and compared with rice growth data such as plant height, stem number, biomass, dry weight and LAI that were collected at time of each scatterometer measurement simultaneously.

• 환경생물
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• 제41권4호
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• pp.463-472
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• 2023

벼의 주요 해충인 먹노린재에 대해 실내에서 충체분무법과 기주분무법을 통해 시판 중인 유기농업자재(EFOM) 27종을 대상으로 살충 활성을 평가하였다. 그 결과, 유기농업자재 7종(EFOM-8, -10, -12, -13, -19, -20, -26)에서 기주식물에만 살포하는 것보다 충체에 직접 살포되어 접촉하는 경우에만 높은 살충 효과를 보였다. 실내 벼 포트 검정에서는 선발된 7종 모두 담수 조건에서 살충률이 73.3% 이상이었으며, 특히 EFOM-13과 EFOM-20은 퇴수 조건에서보다 담수 조건에서 살충률이 1.5~1.8배 높은 차이를 보였다. 야외 간이 검정에서 EFOM-10 (마늘 80%), EFOM13 (님 62%), EFOM-26 (고삼 70%+에틸알콜 28%+제충국 2%)는 7일차 담수한 논에서 88.9%의 높은 방제가를 보였고 퇴수한 논보다 방제가는 1.4~1.9배 높았다. 선발된 EFOM-10을 살포한 농가의 담수한 논에서도 7일차 방제가는 86.2%로 퇴수한 논의 방제가 61.9%보다 1.4배 높았다. 종합적으로 살포액의 충분한 충체 접촉과 논의 담수 조건이 유기농업자재의 방제 효과를 높일 수 있음을 보여주었다. 이러한 연구 결과가 앞으로 농가에서 적용할 수 있는 최적의 먹노린재 방제전략 수립에 도움이 되기를 기대한다.

• 한국습지학회지
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• 제10권3호
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• pp.1-7
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• 2008

본 연구에서는 논에서의 영양물질 제거능력에 대하여 평가하였다. 논을 인공습지라는 관점으로 보고 전라남도 함평군 엄다면 화양리의 논 지구(이하 학야지구)를 시험지구로 선정하여 2004년 5월부터 9월까지 영농기 기간동안 조사하였다. 학야지구를 대상으로 물수지 및 물질수지를 조사하여 논에서의 T-N, T-P의 제거능력을 조사한 결과 지표유출 부하로 T-N, T-P가 각각 20.82 kg/ha, 1.55 kg/ha로 나타났으며, 이는 연구대상 논에 총 투입된 T-N, T-P의 13.2%와 6.4%에 해당되는 양이다. 연구 결과는 투입된 대부분의 영양물질이 논에서 처리됨을 보여주었다.

• 한국환경농학회지
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• 제6권1호
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• pp.31-37
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• 1987

수도재배환경중(水稻栽培環境中) carbofuran의 흡수(吸收), 이행(移行) 및 잔류양상(殘留樣相)을 구명(究明)하기 위하여 소형수도재배구(小型水稻栽培區)를 이용(利用), carbofuran 입제(粒劑)를 2수준(水準)으로 살포(撒布)하고 시기별(時期別)로 수질(水質), 수도체(水稻體),토양(土壤) 및 수확물중(收穫物中) 잔류수준(殘留水準)을 조사(調査)한 결과(結果)는 다음과 같다. 수면살포(水面撒布)한 carbofuran 입제(粒劑)는 빠른 속도(速度)로 용출(溶出)되어 수질중(水質中) carbofuran 농도(濃度)는 처리(處理) 1일이내(日以內)에 최고치(最高値)에도 달하였다. 용출(溶出)된 carbofuran은 수도체(水稻體)로 흡수(吸收), 이행(移行)되어 처리(處理) 1∼3일(日) 후(後)에 최고치(最高値)에 도달하였으며 그 이후(以後) 완만한 감소(減少) 경향(傾向)을 보였다. 수질중(水質中) carbofuran의 반감기(半減期)는 4일(日)이었고 토양중(土壤中)에서의 반감기(半減期)는 처리수준(處理水準)에 따라 8∼12일(日)이었다. 수확물중(收穫物中) carbofuran 잔류량(殘留量)은 현미(玄米)의 경우 0.01∼0.02ppm이었으며 볏짚에서는 0.37∼0.07ppm의 범위(範圍)였다.

• 한국농공학회논문집
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• 제63권4호
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• pp.55-64
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• 2021

The expansion of upland crop cultivation in rice paddy fields is recommended by the Korean government to solve the problem of falling rice price and reduction of rice farmer's income due to oversupply of rice. However, water use efficiency is significantly influenced by the land use change from paddy field to upland. Therefore, this study aimed to evaluate the water budget of soybean grown in using APEX (Agricultural Policy and Environmental eXtender) model. The amount of runoff was measured in a test bed located in Iksan, Jeollabu-do and used to calibrate and validate the simulated runoff by APEX model. From 2019 to 2020, the water budget of soybean grown in uplands were estimated and compared with the one grown in paddy fields. The calibration result of AP EX model for runoff showed that R² (Coefficient of determination) and NSE (Nash-Sutcliffe efficiency) were 0.90 and 0.89, respectively. In addition, the validated results of R² and NSE were 0.81 and 0.62, respectively. The comparative study of each component in water budget showed that the amounts of evapotranspiration and percolation estimated by APEX model were 549.1 mm and 375.8mm, respectively. The direct runoff amount from upland was 390.1 mm, which was less than that from paddy fields. The average amount of irrigation water was 28.7 mm, which was very small compared to the one from paddy fields.

• 농업과학연구
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• 제50권2호
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• pp.257-270
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• 2023

논(paddy) 환경은 습지로 분류되며 담수환경에서 매우 많은 비율을 차지하고 있다. 또한 많은 수서곤충류 및 양서파충류 유생의 서식지 및 산란 장소로써 생태학적으로 매우 중요하다. 하지만 기후변화 및 무분별한 농약 살포 등으로 인해 논 생태계는 지속적으로 위협받고 있다. 따라서 향후 훼손된 논 생태계를 복원하기 위해서는 복원 기준이 될 수 있는 논 생태계 서식 생물들의 정보가 필요하다. 환경유전자 metabarcoding 분석법은 성체 생활시기가 다르거나 성충으로 우화하여 대상 생태계에서 더 이상 발견할 수 없는 분류군까지 존재 여부를 간접적으로 파악할 수 있기 때문에 논 생태계에 서식하는 많은 생물들의 정보를 축적하는데 매우 효과적이다. 본 연구에서도 4종의 개구리와 9종의 수서곤충 유전자가 발견되었으며, 일부 분류군은 현장에서 개체가 직접 발견되었다. 많은 수의 분류군이 DNA 탐색에서만 발견되었으며, 전통적인 조사방법은 매우 제한적인 분류군만을 확인할 수 있었다. 이러한 eDNA 기반의 논 생물탐색은 강력한 분석 해상도 때문에 농업 생태계 생물다양성 조사에서 활용가치가 매우 높을 것으로 판단된다.

• 농약과학회지
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• 제12권1호
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• pp.74-81
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• 2008

벼 재배 환경에서 농약의 분포 및 유출특성과 농업환경으로의 노출성을 구명하기 위해서 살포농약의 제형과 벼 생육단계에 따른 경시적 분포양상 실험을 수행하였다. 벼 이앙전 처리제로 제초제인 butachlor 유탁제와 oxadiazon 유제의 논물 중 잔류양상은 처리 3일 후에 초기처리량의 90%이상이 소실되는 것으로 나타났고, 벼 이앙 후 15일 이내에 처리한 butachlor, thiobencarb 및 molinate 입제의 농약성분의 95%이상이 논물과 토양에 분포되어, 비살포 지역으로 유출을 방지할 수 있는 유출안전기간은 농약살포 후 5일로 설정하였다. 벼 생육 중기에 살포된 iprobenfos 입제, tricyclazole 수화제, phenthoate 유제의 처리직후 2시간 후의 분포는 논물에서 16.1, 48.9와 38.9%, 토양에서 83.6, 15.4와 10.7%, 식물체에서 는 0.3, 35.7과 50.4%가 각각 분포되었다. 또한 벼생육 후기 농약분포는 tricyclazole 수화제와 Phenthoate 유제는 논물에서 7.8과 9.8%, 토양에서 21.7과 5.1%, 식물체에서 70.5와 85.1%가 각각 분포되어 식물체 biomass가 증가 할수록 농약 부착량이 식물체에 분포되어 논물과 토양에 적은 양이 분포되었다.