• Journal of The Korean Society of Agricultural Engineers
• /
• v.64 no.1
• /
• pp.65-77
• /
• 2022

Due to muddy water from the highland fields upstream of Soyangho Lake, the Mandae, Gaa, and Jawoon have been redesignated as NPS management areas. This study aims to evaluate the adequacy and supplementation points of the implementation plan by analyzing the operation status of muddy water generation and reduction facilities through on-site investigations by NPS management area to achieve the effective nonpoint pollution reduction goal in the implementation of the implementation plan established in 2020. The SS load calculated based on the survey results from July to October 2019 from 2017 showed a decreasen in 2019 compared to 2017. Both and the Jawoon were analyzed to have decreased. However, the amount of precipitation also decreased by about 27%, so it was judged that the effect of the reduction project was not significant. As a result of the detailed investigation of abatement facilities, about 86% of the 793 facilities installed in the management area were evaluated as 'good'. As a result of a detailed investigation by subwatersheds, subwatersheds 105 and 106 in the Mandae were analyzed as apprehensive subwatersheds. appeared to fall. In addition, it was analyzed that the effect of reducing muddy water in the Mandae district was insufficient due to the high ratio of leased farmers, lack of efforts to reduce turbid water in leased farmland, conversion to annual crops, and neglect of bare land. In the case of Gaa district, although the abatement facilities are concentrated in the upstream, muddy water was also found to be severe.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.66 no.2
• /
• pp.53-62
• /
• 2024

This study assessed the efficiency of reducing soil erosion and suspended sediment through the restoration of alpine unauthorized and illegally cultivated fields, using the SWAT (Soil and Water Assessment Tool) model in the Mandae District. The results showed that in Scenario 5, which involved restoring unauthorized and illegal fields within forests, along rivers (banks), and in ditch areas were restored to their original land categories, achieved the highest efficiency in reducing average annual soil erosion and suspended sediment, with reductions of 8.1% and 4.5%, respectively. In particular, it was confirmed that the restoration of unauthorized and illegal fields within forested areas has a significant impact. This demonstrated that the restoration of unauthorized and illegal agricultural fields can substantially reduce the soil erosion and suspended sediment attributable to non-point source pollution. Our findings highlight the importance of managing these unauthorized and illegal agricultural activities in developing sustainable strategies within non-point source pollution management areas. This study is expected to provide important basic data to effectively establish water quality improvement strategies in the region of non-point source pollution management.

• Water Engineering Research
• /
• v.5 no.3
• /
• pp.147-156
• /
• 2004

Recently, the population growth, industrial and agricultural development are rapidly undergoing in the Lower Rio Grande Valley (LRGV) in Texas. The Lower Rio Grande Valley (LRGV) composed of the 4 counties and three of them are interesting for Non-point and point source pollutant modeling: Starr, Cameron, and Hidalgo. Especially, the LRGV is an intensively irrigation region, and Texas A&M University Agriculture Program and the New Mexico State University College of Agriculture applied irrigation district program (Guy Fipps and Craig Pope, 1998), projects in GIS and Hydrology based agricultural water management systems and assessment of prioritized protecting stream network, water quality and rehabilitation based on water saving potential in Rio Grande River. In the LRGV region, where point and non-point sources of pollution may be a big concern, because increasing fertilizers and pesticides use and population cause. This project objective seeks to determine the accumulation of non-point and point source and discuss the main impacts of agriculture and environmental concern with water quality related to pesticides, fertilizer, and nutrients within LRGV region. The GIS technique is widely used and developed for the assessment of non-point source pollution in LRGV region. This project shows the losses in kg/$km^2$/year of BOD (Biological Oxygen Demand), TN (total Nitrogen) and TP (total phosphorus) in the runoff from the surface of LRGV.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.56 no.4
• /
• pp.1-8
• /
• 2014

Appropriate amount of water supply to paddy fields in proper time is important to achieve efficient agricultural water management. The purpose of this study is to evaluate the irrigation water supply adequacy for paddy fields using water level data in irrigation canals. For the evaluation, the real-time water level data were collected from main canals in the Dongjin irrigation district for 2 years. Using the water level data, delivered irrigation water amounts at the distribution points of each canal were calculated. The water balance model for paddy field was designed considering intermittent irrigation and the irrigation water requirement was estimated. Irrigation water supply adequacy was analyzed from main canals to the irrigation blocks based on the comparison between estimated requirement and delivered irrigation water amounts. From the adequacy analysis, irrigation water supply showed poor management condition in 2012 with low efficiency except the Daepyong canal section, and the adequacy in 2013 was good or fair except the Yongsung canal section. When irrigation water for paddy fields was insufficient, water supply adequacy was affected by irrigation area, but when irrigation water was enough to supply, adequacy was affected by distance from main canal to distribution points. These results of the spatial and temporal dimensions of the irrigation adequacy could be utilized for efficient irrigation water management to improve the temporal uniformity and equity in the water distribution for paddy fields.

• 한국약용작물학회:학술대회논문집
• /
• 2010.10a
• /
• pp.167-168
• /
• 2010

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1993.10a
• /
• pp.217-226
• /
• 1993

As results of not selecting and using farm well pump properly , it's running regime is far away from high efficient zone and running efficiency of farm well pump is lower. The paper analyses unhealthy tendencies of technical state of diving-electric pump, deep well and centrifugal pump which are commonly used in our country. The paper also summarizes several technical innovation plans to raise efficiency : stage change plan, diameter change plan, speed change plan and synthetic technical innovation . Each plan gives a detailed introduction of designing and construction manners, through practical measuring , the synthetic efficiency of innovated well pumps raise above 30 percent. Economic benefit is evident.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.36 no.3
• /
• pp.47-59
• /
• 1994

The irrigation reservoir operation models developed were tested with weather and field data, and the sensitivity of the water requirement deficiency indices(WRDI) were checked with different initial reservoir storages, irrigated areas, and other water uses from the reservoir storage. Seven reservoir release rules were applied to Yongseol Reservoir. Twenty year WRDIs were computed to check performances of those reservoir release rules. Mean WRDIs were 138, 198, 198, 200, 240, 344, and 1033mm for ROM, TOS, COS, CRR, MSC, FAS, and SRC, respectively. The results indicated that ROM contributes consistently to higher operation efficiencies of an irrigation reservoir. The test results of LFROM and SFROM showed that reservoir operation with the proposed optimization technique ROM would be better suited for an irrigation district than those with the other rules. And the proposed model could be used as a tool to improve reservoir operations.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.62 no.2
• /
• pp.97-109
• /
• 2020

Drought is one of the most influential disasters in sustainable agriculture and food security of nations. In order to preemptively respond to agricultural droughts, vulnerability assessments were conducted to predict the possibility of drought in the region, the degree of direct or indirect damage, and the ability to cope with the damage. Information on agricultural drought vulnerability status of different regions is extremely useful for implementation of long term drought management measures. The purpose of this study is to develop and implement a quantitative approach for measuring agricultural drought vulnerability at sub-district level based on agricultural water and reservoirs. To assess the vulnerability in a quantitative manner and also to deal with different physical and socioeconomic data on the occurrence of agricultural drought, we selected the appropriate factors for the assessment of agricultural drought vulnerability through preceding studies, and analyzed the meteorological and agricultural reservoir data from 2015 to 2018. Each item was weighted using AHP (Analytic Hierarchy Process) analysis and evaluated through the agricultural drought vulnerability estimation. The entire national vulnerability assessments showed that Ganghwa, Naju, and Damyang were the most vulnerable to agricultural droughts. As a result of analyzing spatial expression, Gyeongsang-do is relatively more vulnerable to drought than Gangwon-do and Gyeonggi-do. The results revealed that the methodology and evaluation items achieved good performance in drought response. In addition, vulnerability assessments based on agricultural reservoir are expected to contribute supporting effective drought decisions in the field of agricultural water management.

• Korean journal of applied entomology
• /
• v.46 no.3
• /
• pp.437-444
• /
• 2007

The effect of environmental factors on the over-wintering success of the apple snail, Pomacea canaliculata, which is considered as unable to hibernate during winter climate in Korea. This study was examined to determine the location of over-wintering habitats in the agricultural water system related with weed control using the apple snail in rice paddy field in the Yeongnam district from 2003 to 2006. Over-wintering success of the apple snail was observed at Hadong, Hapchen, Sanchung, Kimhae, Milyang, Changwon, Ulsan, Busan, Gyengju, Pohang, Chilgok, Seongju, Gumi, Sangju and Youngju in Yeongnam area. And the over-wintering locations of apple snail going north year by year. Accordingly, the successful over-wintering sites observed were deep wells, water running canals and brooks not dried conditions. A special feature of this sites was that the water of this sites was not frozen during winter season.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.62 no.4
• /
• pp.1-12
• /
• 2020

The extreme 2017 spring drought affected a large portion of South Korea in the Southern Gyeonggi-do and Chungcheongnam-do districts. This drought event was one of the climatologically driest spring seasons over the 1961-2016 period of record. It was characterized by exceptionally low reservoir water levels, with the average water level being 36% lower over most of western South Korea. In this study, we consider drought response methods to alleviate the shortage of agricultural water in times of drought. It could be to store water from a stream into a reservoir. There is a cyclical method for reusing water supplied from a reservoir into streams through drainage. We intended to present a decision-making plan for water supply based on the calculation of the quantity of water supply and leakage. We compared the rainfall-runoff equation with the TANK model, which is a long-term run-off model. Estimations of reservoir inflow during non-irrigation seasons applied to the Madun, Daesa, and Pungjeon reservoirs. We applied the run-off flow to the last 30 years of rainfall data to estimate reservoir storage. We calculated the available water in the river during the non-irrigation season. The daily average inflow from 2003 to 2018 was calculated from October to April. Simulation results show that an average of 67,000 tons of water is obtained during the non-irrigation season. The report shows that about 53,000 tons of water are available except during the winter season from December to February. The Madun Reservoir began in early October with a 10 percent storage rate. In the starting ratio, a simulated rate of 4 K, 6 K, and 8 K tons is predicted to be 44%, 50%, and 60%. We can estimate the amount of water needed and the timing of water pump operations during the non-irrigation season that focuses on fresh water reservoirs and improve decision making for efficient water supplies.