• 한국농공학회논문집
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• 제59권2호
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• pp.29-36
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• 2017

The objective of this study was to analyze the temporal and spatial characteristics of agricultural drought by tracking the daily reservoir storage in Chungnam province. All daily records of the percent of reservoir storage from 2000 to 2015 were collected for 130 irrigation reservoirs from the RIMS (Rural Infrastructure Management System). The temporal change of province-wide average reservoir storage and the statistics showed that the annual average and minimum percent of reservoir storage in 2015 were extremely low like as those in the historical drought years of 2001 and 2012. The minimum reservoir storage on record was a 41 % at the end of September and remained far less than its historical average even until the end of the year. Furthermore, the annual average reservoir storage (68.3 %) recorded the lowest on record since 2000. In addition, about half of 130 major irrigation reservoirs in Chungnam fell into the risk of water shortage below 30 % full, and, in terms of annual minimum reservoir storage, the 79 reservoirs yielded lower storage in 2015 comparing with the measured in another drought year, 2001. On the other hand, irrigation reservoirs of comparatively worse storage condition revealed to be mostly located on the inside, such as Cheongyang-gun and Hongsung-gun. Conclusively, the low reservoir storage, still far below average even on December 2015, induced a serious concern about that more extreme drought would happen in the next spring.

• 농업과학연구
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• 제41권3호
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• pp.187-191
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• 2014

The cultivation area and use of genetically modified (GM) crops have been increased continuously over the world. Concerns about the potential risks of GM crops are also increasing. Safe management for the development and production of GM crops is required according to Living Modified Organism Act in Korea. Planning about the methods, duration, and frequency of environmental monitoring is also required for commercial use of GM crops. GM Zoysia japonica Steud. (event name: JG21) expressing resistance to glufosinate-ammonium has been generated previously. By using gamma ray treatment to JG21 we also developed male sterility and dwarf Z. japonica (event name: JG21-MS). The objective of this study was to establish the monitoring system for environment release of JG21-MS. In this study we extracted RNA from JG21 and JG21-MS and conducted RAPD (random amplified polymorphic DNA) method to distinguish JG21 and JG21-MS.

• 한국식품위생안전성학회지
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• 제34권3호
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• pp.283-289
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• 2019

본 연구에서는 광주광역시 학교급식 농산물의 잔류농약을 모니터링하고 섭취량에 따른 위해평가를 실시하였다. 2015년부터 2017년 까지 광주광역시 소재 학교에 공급되는 농산물 320건을 실험대상으로 하였다. 농산물 전처리 및 잔류농약 분석은 식품공전 다종 농약 다성분 분석 제2법에 따라 120종의 잔류농약을 실험하였다. 검량선에 대한 직선성 상관계수는 0.9923~1.0000, LOD는 0.004~0.019 mg/kg, LOQ는 0.012~0.057 mg/kg으로 양호하게 나타났으며 회수율은 79.1~100.2%로 나타났다. 학교급식에 사용되는 농산물 320건 중 18건(5.6%)에서 잔류농약이 검출되었으며, 고구마 순 1건(0.3%)이 잔류농약허용기준을 초과하였다. 잔류농약 검출빈도는 고추 8회, 파프리카 3회로 다른 농산물에 비해 높은 검출빈도를 나타내었고 가장 높은 검출빈도를 나타낸 잔류농약은 boscalid(4회)와 acetamiprid(3회)로 나타났다. 실험결과 학교급식 농산물 중 고추, 파프리카, 고구마 순에 대한 잔류농약 관리가 필요한 것으로 나타났다. 잔류농약 위해도 평가 결과 고구마 순에서 검출된 bifenthrin이 64.18%로 가장 높았으며, 고추에서 검출된 boscalid 등의 Hazard index는 0.03~8.23%로 나타나 학교급식 농산물의 Hazard index는 안전한 수준으로 평가되었다. 그러나 채소류를 학교급식 식재료로 제공할 경우 잔류농약 식이섭취량을 최소화하기 위해 철저한 세척이 필요한 것으로 판단되며 친환경 농산물의 식재료 보급 확대가 필요한 것으로 판단된다.

• 한국농림기상학회지
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• 제23권3호
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• pp.149-155
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• 2021

농업기상재해 조기경보시스템에서는 일 최대순간 풍속에 과수의 낙과 피해 임계풍속을 대입하여 농작물의 풍해 위험을 예측, 자원농가에게 제공하고 있다. 강풍의 위험 예측확률을 높이기 위한 방법으로써, 기존 방식에서 '안전'으로 분류된 데이터들 중 실제로는 풍해위험이 있는 경우를 찾아내는 인공신경망 이항분류 기법을 도입하였다. 학습데이터는 전라남북도와 경북 및 경남 일부지역의 총 210개소 기상청 종관 및 방재기상관측지점에서 수집된 2019년 전체 일별 풍속자료이며, 최적 모델 도출을 위한 검증데이터는 동일지점의 2020년 1월 1일~12월 12일 자료를, 인공신경망 기법 사용 전/후의 풍해위험예측 성능 평가는 2020년 12월 13일~2021년 2월 18일까지의 자료를 사용하였다. 풍해위험 임계풍속은 과수의 낙과 피해기준으로 주로 사용되고 있는 11m/s를 설정하였다. 또한 2020년 동일 기간의 일 최대순간풍속 실측값으로 Weibull 분포를 작성한 후, 추정값과 임계풍속간의 편차를 이용하여 누적확률값을 계산, 풍해 경보에서 한 단계 낮은 주의보를 판단하고 인공신경망 기법 적용 결과와 비교하였다. 평가기간 중 기존의 풍해 위험 탐지확률은 65.36%였으나 인공신경망 기법으로 재분류 과정을 거친 후 93.62%로 크게 개선되었다. 반면, 오보율이 함께 증가되어(13.46% → 37.64%), 전반적인 정확도는 감소하였다. 한편 Weibull 분포를 이용하여 풍해주의보 구간을 두었을 때는 정확도 83.46%으로 인공신경망 기법에 비해 전반적인 예측 정확도는 더 높았던 반면 위험 탐지확률은 88.79%로 더 낮게 나타났다. 따라서, 상대적으로 위험예보의 미예측이 중대한 문제가 되는 사례에서 인공신경망 방식이 유용할 것으로 보인다.

• Weed & Turfgrass Science
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• 제3권4호
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• pp.305-311
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• 2014

유전자변형(genetically modified, GM)작물의 종자 및 꽃가루를 통한 환경 생태계로의 확산은 안전성평가와 안전관리에 있어 매우 중요한 요소이며, 국내에서는 LMO법에 따라 GM 작물의 개발 및 생산 등에 대한 안전관리와 GM 작물의 상업화를 위한 환경모니터링에 대한 방법, 기간, 빈도 등에 대한 계획을 요구하고 있다. 본 연구는 제초제저항성 들잔디(zoysiagrass)의 야외환경모니터링을 수행을 통한 환경모니터링 시스템 기반 구축을 위해 수행되었다. 연구에 사용된 GM 들잔디는 제초제저항 형질의 JG21과 JG21에 방사능처리로 웅성불임을 유도한 JG21-MS 등 2개의 이벤트를 이용하였다. 환경모니터링은 충남 성환, 충북 오창, 제주대 및 제주 납원읍 등 4개 격리포장 주변에서 2011년부터 2013년까지 종자 및 영양번식체에 의한 산포 조사와 화분에 의한 유전자이동에 대해 수행되었다. 모니터링 수행 결과 3개 지역에서 유전자이동 및 산포가 발견되지 않았으나, 2012년 제주 남원읍 지역 조사에서 격리포장 주변 2 m 부근에서 JG21 들잔디 1개체의 유출이 발견되어 보고 및 안전관리 조치를 수행하였다. 본 연구에서 사용된 GM 들잔디의 검출 방법과 환경모니터링 기법들은 GM 들잔디 개발을 위한 포장시험 연구와 상업화 후 환경모니터링을 위한 기초자료로 활용될 수 있을 것으로 기대한다.

• 농촌계획
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• 제22권2호
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• pp.19-29
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• 2016

Disasters that occur most frequently in rural areas are drought, flood, damages from wind and cold weather. Among these, damages from storm and flood and drought are the main disasters and recently, these are occurring on a large scale due to unusual weather conditions. Under such circumstances, projects and researches on disasters in rural areas are under way but they are mostly targeting one area or making approaches focusing on repair facilities, maintenance project of facilities in small streams, and disaster management, so there have not been enough studies on the current status of overall damaged facilities in the rural areas. Against this backdrop, through the analysis of the current status of damaged facilities due to storm and flood in rural areas, this study aims to provide base data for policies needed for disaster recovery planning and maintenance work of rural areas. For the analysis of damaged facilities due to storm and flood in rural areas, using the annual report on disasters issued by Ministry of Public Safety and Security and based on the occurrence rate of estimated damage in each city and district for the past 10 years(2004~2013), 8 areas with the highest number of occurrence and cost of damage were found from each province and target areas were selected. Then, regarding the selected target areas, the General Plan for Reducing Damages from Storm and Flood, which is the report on top-level plan for preventing disasters, was secured and the current status of damaged facilities were analyzed. After organizing the analysis of current status, the tendency of damaged facilities due to storm and flood in rural areas, the items of damaged facilities depending on the types of storm and flood damages, and risk factors were suggested. Based on this result, in order to generalize the results of follow-up researches, it is thought that disaster recovery planning and establishing the system of remodeling items necessary for maintenance work would be possible by analyzing damage investigation items recorded in additional researches on rural areas, researches on natural disasters, and recovery plan instructions and by conducting on-site investigation on the damaged villages from storm and flood in rural areas.

• 한국농공학회논문집
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• 제49권4호
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• pp.13-22
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• 2007

The uncertainty in water quality model predictions is inevitably high due to natural stochasticity, model uncertainty, and parameter uncertainty. An integrated modeling system under uncertainty was described and demonstrated for use in watershed management and receiving-water quality prediction. A watershed model (HSPF), a receiving water quality model (WASP), and a wetland model (NPS-WET) were incorporated into an integrated modeling system (modified-BASINS) and applied to the Hwaseong Reservoir watershed. Reservoir water quality was predicted using the calibrated integrated modeling system, and the deterministic integrated modeling output was useful for estimating mean water quality given future watershed conditions and assessing the spatial distribution of pollutant loads. A Monte Carlo simulation was used to investigate the effect of various uncertainties on output prediction. Without pollution control measures in the watershed, the concentrations of total nitrogen (T-N) and total phosphorous (T-P) in the Hwaseong Reservoir, considering uncertainty, would be less than about 4.8 and 0.26 mg 4.8 and 0.26 mg $L^{-1}$, respectively, with 95% confidence. The effects of two watershed management practices, a wastewater treatment plant (WWTP) and a constructed wetland (WETLAND), were evaluated. The combined scenario (WWTP + WETLAND) was the most effective at improving reservoir water quality, bringing concentrations of T-N and T-P in the Hwaseong Reservoir to less than 3.54 and 0.15 mg ${L^{-1}$, 26.7 and 42.9% improvements, respectively, with 95% confidence. Overall, the Monte Carlo simulation in the integrated modeling system was practical for estimating uncertainty and reliable in water quality prediction. The approach described here may allow decisions to be made based on probability and level of risk, and its application is recommended.

• 한국농공학회논문집
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• 제59권1호
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• pp.81-96
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• 2017

Along with climate change, it is reported that the scale and the frequency of extreme climate events (e.g. heavy rain, typhoon, etc.) show unstable tendency of increase. In case of Korea, also, the frequency of heavy rainfall shows increasing tendency, thus causing natural disaster damage in downtown and agricultural areas by rainfall that exceeds the design criteria of hydraulic structures. In order to minimize natural disaster damage, it is necessary to analyze how extreme precipitation event changes under climate change. Therefore a new design criteria based on non-stationarity frequency analysis is needed to consider a tendency of future extreme precipitation event and to prepare countermeasures to climate change. And a quantitative and objective characteristic analysis could be a key to preparing countermeasures to climate change impact. In this study, non-stationarity frequency analysis was performed and inundation risk indices developed by 4 inundation characteristics (e.g. inundation area, inundation depth, inundation duration, and inundation radius) were assessed. The study results showed that future probable rainfall could exceed the existing design criteria of hydraulic structures (rivers of state: 100yr-200yr, river banks: 50yr-100yr) reaching over 500yr frequency probable rainfall of the past. Inundation characteristics showed higher value in the future compared to the past, especially in sections with tributary stream inflow. Also, the inundation risk indices were estimated as 0.14 for the past period of 1973-2015, and 0.25, 0.29, 1.27 for the future period of 2016-2040, 2041-2070, 2071-2100, respectively. The study findings are expected to be used as a basis to analyze future inundation damage and to establish management solutions for rivers with inundation risks.

• The Plant Pathology Journal
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• 제24권1호
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• pp.46-51
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• 2008

With the goal of achieving better integrated pest management for hot pepper, a disease-forecasting system was compared to a conventional disease-control method. Experimental field plots were established at Asan, Chungnam, in 2005 to 2006, and hourly temperature and leaf wetness were measured and used as model inputs. One treatment group received applications of a protective fungicide, dithianon, every 7 days, whereas another received a curative fungicide, dimethomorph, when the model-determined infection risk (IR) exceeded a value of 3. In the unsprayed plot, fruits showed 18.9% (2005) and 14.0% (2006) anthracnose infection. Fruits sprayed with dithianon at 7-day intervals had 4.7% (2005) and 15.4% (2006) infection. The receiving model-advised sprays of dimethomorph had 9.4% (2005) and 10.9% (2006) anthracnose infection. Differences in the anthracnose levels between the conventional and model-advised treatments were not statistically significant. The efficacy of 10 (2005) and 8 (2006) applications of calendar-based sprays was same as that of three (2005 and 2006) sprays based on the disease-forecast system. In addition, we found much higher the IRs with the leaf wetness sensor from the field plots comparing without leaf wetness sensor from the weather station at Asan within 10km away. Since the wetness-periods were critical to forecast anthracnose in the model, the measurement of wetness-period in commercial fields must be refined to improve the anthracnose-forecast model.

• Animal Bioscience
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• 제34권4호
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• pp.539-545
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• 2021

Objective: Endometritis is a major disease, that causes infertility in cattle, and is usually categorized as clinical or subclinical endometritis (SCE). The nutritional condition during the dry period is important for recovery after the last stage of the lactation period, and for postpartum production and reproduction. This study aimed to clarify the relationship between nutritional and metabolic characteristics in the dry period, and the risk of postpartum SCE. Methods: Multiparous Holstein dairy cows (n = 25, raised in a tied stall) were used. Endometrial cytological analysis was performed around 30 days post-partum, with 5% to 14% polymorphonuclear (PMN) as a cut-off point to define SCE. Serum levels of glucose, non-esterified fatty acids, β-hydroxybutyric acid (BHBA), blood urea nitrogen, total cholesterol, aspartate aminotransferase, γ-glutamyl transpeptidase, calcium, phosphorus, and magnesium were measured in the cows at the dry period to evaluate energy status, protein metabolism, and mineral metabolism. Results: The incidence of SCE in the cows was 60.0% (n = 15/25) and the mean PMN% in postpartum cows diagnosed as SCE was 8.05%±2.6%. Overall, 17 and 8 samples were collected from the cows in the far-off and close-up periods, respectively. The serum concentration of BHBA in the far-off period and serum glucose concentration in the closeup period were correlated with postpartum PMN% (r = 0.62, p<0.01; r = -0.74, p<0.05, respectively). Serum levels of calcium and magnesium in the dry period were associated with the incidence of postpartum SCE (healthy vs SCE cows, p<0.05). Conclusion: Blood levels of glucose, BHBA, calcium, and magnesium in dry periods could be useful parameters for predicting the risk of postpartum SCE. The present study also suggests that management in the close-up period is essential for promoting recovery from calving fatigue.