• 생물환경조절학회지
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• 제15권2호
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• pp.156-161
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• 2006

토마토 초장의 경우 심층수처리는 대조구에 비해 두상관수는 50%, 저면관수는 58% 감소하였고, 표층수 처리구에서는 두상관수는 49%, 저면관수는 56% 감소하였으며, NaCl 처리구에서는 두상관수는 47%, 저면관수는 57%감소하여 저면관수 처리방법이 도장억제에 더 효과적이었다. 지상부 생체중의 경우 두상관수보다 저면관수에서 더 감소하는 경향을 보였으나 뚜렷한 차이가 나타나지 않았다. 지하부 생체중 대조구에 비하여 두상관수는 38%정도 감소한 반면 저면관수는 49% 정도 감소하여, 저면관수에 의해 생육이 현저히 억제되는 결과를 보였다. 지상부와 지하부의 건물중은 생체중과 비슷한 경향을 나타냈다. 이와 같은 결과는 염에 의한 뿌리생육의 저하 때문인 것으로 판단된다. 경경은 대조구에 비해 감소하였지만 처리 방법 간에 뚜렷한 차이를 보이지는 않았다. T/R률에 비추어 보면 두상관수 처리에서 묘소질이 더 뛰어났으나, 묘의 충실도(compactness)는 처리구간 차이는 나타나지 않았다. 토마토의 경우 초장의 억제정도나 묘의 충실도에 비춰보아 저면관수 방법이 도장억제에 더 효과적이라 사료된다. 오이의 경우 처리 농도의 증가에 따라 초장, 생체중, 건물중, 경경, 엽면적이 감소하였다. 저면관수가 두상관수에 비해 도장억제 효과와, 생육억제가 좀 더 뚜렷이 나타나기는 하였으나 두 처리간의 유의적 차이는 나타나지 않았다.

• 한국농공학회논문집
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• 제61권2호
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• pp.97-104
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• 2019

The purpose of this study was to establish the estimation method of irrigation water amount for sewage treated water reuse for agricultural purpose. To calculate the irrigation water amount, we adopted Penman-Monteith for potential evapotranspiration estimation and applied crop coefficient and irrigation efficiency factor. We developed the irrigation water amount calculation program using C language in Xcode environment. The target district for calculation is having 259 ha of agricultural land located near the Jinyeong Clear Water Circulation Center in Hanrim-myeon, Gimhae city. The meteorological data of the study area were obtained from Changwon weather station from 1986 to 2017. Calculated average and maximum of annual mean potential evapotranspiration were 2.72 mm/day and 6.22 mm/day, respectively. We used K-S (Kolmogorov-Smirnov) for goodness-of-fit test to find optimal probability distribution of annual mean and maximum evapotranspiration. As a result, the normal distribution was selected for the appropriate distribution. The annual mean and maximum potential evapotranspiration for 10-year return period by applying normal distribution were 2.88 mm/day and 6.76 mm/day, respectively. Assuming that the irrigation efficiency is 80%, the irrigation water requirement was calculated as $36.05m^3/day/ha$ and $84.45m^3/day/ha$, respectively, when annual mean and maximum potential evapotranspiration were applied. The actual irrigation water amount can be calculated by applying the crop coefficient and cropping days for the study area based on the developed irrigation water amount estimation program in this study.

• 농업과학연구
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• 제31권1호
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• pp.53-75
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• 2004

This study is aimed at identifying the national economic value of the irrigation facilities by reviewing the existing papers on economic values of the irrigation facilities and presenting current status of dual O & M problems of the irrigation facilities. This study suggested the unified O & M system rather than continuing the existing dual O & M system of irrigation facilities based on the surveyed results of the activities of irrigation fraternities in Chungnam Province. The findings and proposals for the successful unified and mono O & M system of the irrigation facilities are as follows: (1) Total number of irrigation facilities in the nation accounts for 67,582, while the total length of irrigation and drainage canals amounted to about 174,259km. On account of the total length of structural canals was estimated at 31%, much losses of water and much O & M costs have been inevitable for the full irrigation rice culture. In spite of the past heavy investment for irrigation facilities, the ratio of rain-fed and partially irrigated paddy fields accounts for 23% in 2003. Both Korea Agricultural and Rural Infrastructure Corporation (KARICO) and the city and Gun Governments have managed the irrigation facilities separately by irrigation fraternities. The KARICO have commanded 59% of irrigation paddy area with 18% of the total irrigation facilities, while the city and Gun governments covered 41% of irrigation paddy area with 82% of the existing number of irrigation facilities representing small and medium scale. (2) The 1999 demand prices of irrigation water per ton expressed in 2000 constant market price was estimated at 388 won, the supply price was amounted to 184 won per ton. Considering the supply and demand curve of the irrigation water, the existing irrigation facilities could not satisfy the demand of irrigation water. (3) In 1999, total present added value of the irrigation facilities during the economic life accounted for 48 trillion won, while total supply cost was 44.7 trillion won. The marginal benefit and cost ratio of irrigation water was 1.08. (4) The total O & M cost per year amounting to 681.1 billion won have been required to maintain and repair the existing irrigation facilities in Korea. For the successful unified O & M of irrigation facilities covering whole irrigated paddy field in Korea, 950 billion won of O & M costs are required to keep up the marginal benefit of irrigation water as 2,800 billion won per year. The total O & M cost as 950 billion won should be allocated 40%, 380 billion won for O & M costs of irrigation facilities and 60%, 570 billion won for improvement of irrigation facilities. (5) The study investigated and reviewed the present O & M status of the irrigation facilities by small and medium irrigation fraternities. Most of the farmers belong to the irrigation fraternities preferred not only unified O & M but also KARICO take-over of the whole O & M activities of the irrigation facilities. The prevailing O & M cost per 10a expended by the Corporation was amounted to 104,890 won, while that of city and Gun governments was only amounted to 4,600 won per 10a. regarding the small amount of O & M cost expended by city and Gun governments, it is evident that the existing irrigation system have been managed ineffectively and deteriorated the facilities comparing that of KARICO. In conclusion, the Government could not satisfied the demand of irrigation water by suppling water with existing irrigation facilities. Therefore new additional investment and financial support for irrigation water development should be made to convert rain-fed and partially irrigated paddy fields into fully irrigated ones. The operation and maintenance cost should be supported to keep the marginal values of rice production of existing irrigation facilities in the national economy and to modernize the obsolete irrigation facilities. By unifying the existing dual O & M systems, all the farmers belong to the irrigated paddy fields have to be equally benefited and could be increased their farm income and be stabilized their rural lives.

• 한국농공학회논문집
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• 제48권2호
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• pp.77-87
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• 2006

The reuse of wastewater for agricultural irrigation may cause human health risk as a result of exposure to pathogens. This study conducted the quantitative microbial risk assessment in paddy field irrigated with treated wastewater. Six treatments were used to irrigate the paddy field from Year 2003 to Year 2005: biofilter-effluent, UV-disinfected water (6, 16, 40, 68 $mW s cm^{-2}$), pond-treated water, wetland-treated water, conventional irrigation water and tap water. Total coliforms, fecal coliforms and E. coli were monitored during rice growing period. Beta - Poisson model was employed to calculate the microbial risk of pathogens ingestion that may occur to farmers and neighbor children. Uncertainty of risk was estimated using Monte Carlo simulation. In this study, the microbial risk was higher during initial cultivation (end of May$\sim$June), and it decreased with time. Biofilter effluent (secondary effluent) irrigation showed higher risk values than others (>$10^{-4}$) and irrigation with UV-disinfected water has the lowest risk range ($10^{-6}{\sim}10^{-5}$). The risk value estimated in 2005 was lower than risk value in 2003 and 2004, it is likely due to clean tap water irrigation in initial transplanting stage. It is suggested that irrigation with UV-disinfected water and pond-treated water would reduce the microbial risk associated with wastewater irrigation in paddy field. In addition, the first irrigation water quality significantly affected the subsequent microbial risk.

• 한국농공학회논문집
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• 제48권3호
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• pp.11-20
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• 2006

In this study, the actual water management were investigated and analyzed on site for effective use of the paddy irrigation water. And this study is tried to analyze the difference between simulated irrigation water according to current design method and actual water supply in experimental reservoirs. The reservoirs in Idong, Yongdeok and Misan, which are managed by Korea Rural Community & Agriculture Corporation, were selected fur field investigation. The purpose of this study is to suggest an improved method for irrigation water calculation through quantitative and periodical analysis considering the difference between design and actual field condition.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.551-554
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• 2003

This study was carried out to investigate the effects of the pH of irrigation water on the growth, yield, and grain quality of rice. It acquire fundamental knowledges to set up irrigation water quality standards. The pot experiment was conducted with 5 treatments using irrigation waters with various pH values(control, 4, 6, 8, 10) and replicated four times with randomized block design. The results of this study showed that the uptake of N, P, and K, Ripened grain ratio and yield of rice tended to be reduced at the irrigation water of pH 4 and pH 10. P uptake, Ripened grain ratio and yield of rice at pH 4 water were significantly lower than the control. K uptake at pH 10 water was significantly lower than the control. Plant height, SPAD value and protein content of rice were not affected by the pH of irrigation water.

• 한국농공학회논문집
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• 제46권5호
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• pp.3-11
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• 2004

The objective of this study is to develop water saving irrigation method using water balance model in order to save rural water. Daily water balance components such as irrigation water, drainage water, effective rainfall, ET, and infiltration were measured in paddy fields. Model simulations were performed for different outlet heights and ponding depths. The outlet heights and the ponding depths are 2 cm, 4 cm, 6 cm, 8 cm, and 10 cm, respectively. Based on the simulation very shallow ponding depth of 2 cm with 10 cm outlet height showed the largest effective rainfall ratio and the smallest irrigation amount. Until the introduction of laser leveling dozer and automatic inlet control devices, it would be desirable to adopt 4cm ponding depth because of difficulty of land leveling and frequency of farmer's field visit. The results of this study will be applied in the paddy farming and can improve water use efficiency.

• 한국토양비료학회지
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• 제45권2호
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• pp.312-316
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• 2012

1. 우리나라 북부 8개 지역을 대상으로 하여 최근 30년간의 기상자료 분석에 의한 12월~6월의 일평균 PET는 $2.31mm\;day^{-1}$ 이었다. 2. 시설재배 고추의 우리나라 북부 8개 지역별, 3개 토성 및 16개 순별, 총 384경우의 재배여건에 적합한 물 절약형 적정 관개간격 및 1회 관개량을 산정하였다.

• 한국관개배수논문집
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• 제7권1호
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• pp.19-26
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• 2000

The irrigation water supply and water quality from a pumping station were surveyed. Guiseok pumping station was selected as a monitoring site. Water level in irrigation canal was monitored continuously and water samples were taken and analyzed, periodical

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.111-116
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• 1999

The daily irrigation water intakes from five reservoirs were measured and the water management characteristics analyzed . During the irrigation seasons in 1998 , the total water supply rates ranged from 534 to 864 mm, and thedelivery losses varied from5 to 17 pervent. Major factors affecting the water supply rates were rice transplanting and water management , and rainfall distributions during the growing seasons. The consumptive uses and effective rainfall from each researvoir were compared satisfactorily with the simulated results from the Daily Irrigation Reservoir Operation Model , DIROM.