• 한국관개배수논문집
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• 제2권2호
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• pp.20-26
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• 1995

A three year project was carried out to determine the discharge of major nutrients from the agricultural land to the catchment basin during rice-season, i.e. May to October. The catchment area was 96.2ha, which was consisted of 12.5 ha for the paddy rice

• 한국관개배수논문집
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• 제9권2호
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• pp.51-58
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• 2002

The purpose of this study is to construct a Water Quality Management System (WQMS) for the Saemangeum watershed based on the linkage of water quality model, i .e. QUALfE, and GIS database to estimate water quality effectively in this area. There are three

• 한국관개배수논문집
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• 제3권1호
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• pp.20-31
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• 1996

Several drought indices, which indicate the severity of drought in a reservoir or an irrigated area, have been suggested in home and overseas. However, the indices have not been adopted because those were extremely difficult to be understood by the genera

• 한국관개배수논문집
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• 제8권2호
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• pp.45-54
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• 2001

A plenty of wastes by greenhouse cultivation affect soil and water pollution much more than those by rice cultivation in paddy field. The greenhouse on paddy field has been increased dramatically, however their physical information such as the location an

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.422-425
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• 2003

Many pumping station of Maehang-ri of Hwasung city are established for irrigation water supply, and brine permeation phenomenon is happening thereby. Proposed optimum pumping fluid amount conclusion model that use tidal efficiency and Ghyben-Hertzberg theory so that brine does not permeate in pumping station hereupon and applied this in study area.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권2호
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• pp.97-103
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• 2009

Sericulturists in the vicinity of Bangalore city irrigate their mulberry gardens with Vrishabhavathy stream water, which is polluted with domestic and industrial wastes from the city. To investigate the effect of pollutants on silkworm crops, a detailed field survey was conducted to study the cocoon yield pattern of the crops raised on mulberry irrigated with wastewater as against irrigation by bore/open wells. The villages along the stream were grouped into five test batches at about a distance of $5{\sim}8$ km from each other. The seasonal yield data with relevant information were collected through questionnaires from 117 rearers using stream water and 35 rearers using bore/open wells, the latter serving as control group. The average yield for 100 layings was 46 to 57 kg in the control group whereas in test groups, it ranged between 34 to 51 kg in the first test group and 22 to 38 kg in the rest. The difference in yield was $9{\sim}19$ kg depending on the season between control and test batches. In summer, this difference was higher, with high co-efficient of variation in test groups ($33{\sim}52$%). Further, water, soil and leaf samples were collected from selected rearers and were analyzed for zinc, copper, iron, lead and nickel. Results indicated significantly higher contents of these metals in samples from gardens using wastewater when compared control samples. Significantly (p<0.05 & p<0.01)) higher levels of zinc ($24{\sim}122$ ppm) and iron ($208{\sim}683$ ppm) were noticed in mulberry leaves during summer followed by winter and rainy season. The significance of high content of heavy metals in mulberry leaves and cocoon yield pattern of this area in relation to the quality of irrigation water is discussed.

• 한국농공학회논문집
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• 제60권6호
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• pp.33-42
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• 2018

This study evaluated the vulnerability of irrigation water supplied to the crops. The target areas were selected as Dangjin-si, Yesan-gun, and Cheongyang-gun. The survey items of the climate exposure were annual precipitation and rainless days. The sensitivity survey items were cultivation area, groundwater level, evapotranspiration and groundwater consumption. The survey items of the adaptability were Number of groundwater well and Water supply ratio. The survey methods for these items were investigated in a variety of ways, including "National Climate Data Service System", "Korean Statistical Information Service", "National ground water monitoring network in korea annual report" and "Chungcheongnam-do Statistical Yearbook", "HOMWRS". Vulnerability assessment results were rated within the range of 0~100 points. The first grade was rated 0-25, the second grade 26-50, the third grade 51-75, and the fourth grade 76-100. And the lower the score, the lower the vulnerability. As a result, Cheongyang-gun showed a high vulnerability of over 50 points, Dangjin-si showed a low vulnerability rating of 31.20 points and a Yesan-gun of 36.00 points.

• 한국농공학회지
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• 제43권2호
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• pp.59-68
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• 2001

A water balance analysis was performed for a paddy field neighboring the Dongchang stream, downstream of the Unmun reservoir, which is constructed for the urban water supply. Daily rainfall data were collected and irrigation water flow rate, drainage flow rate, evaportranspiration, infiltration, and piezometeric head were measured in the field. The flow rates were continuously observed by water level logger during the growing season. The evaportranspiration and the infiltration were measured by N-type depletion meter and cylindrical infiltrometer, respectively. PVC pipes with 12mm diameter were used for piezometric head measurement. Total Irrigation and drainage flows were 3,608mm and 1,170mm in 1999, and 3,971mm and 1,548mm in 2000, respectively. The mean and range of the daily infiltration rate were 4.4mm/d and 3.4mm/d to 5.5mm/d in 1999 and 5.1mm/d and 4.1mm/d to 6.5mm/d in 2000, respectively. The net ground water flow including the change of soil water storage was 2,855mm in 1999 and 2,540mm in 2000. The evapotranspiration was 458.3mm in 1999 and 553.5mm in 2000. The range of daily evapotranspiration rate was from 1.6 to 8.7mm/d. The return flow ratio was about 32% in 1999 and 39% in 2000 and three year average was 35% including previous study in 1997. The amount of irrigation water was much higher than design standards or references in this study, This was caused by the inadequate water management practice in the area where water was oversupplied on farmers’ request rather than following sound water management principles.

• 한국농공학회논문집
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• 제54권2호
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• pp.77-86
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• 2012

This study was aim to predict future land-cover changes and to analyze regional land-cover changes in irrigation areas and agricultural reservoir watersheds under climate change scenario. To simulate the future land-cover under climate change scenario - A1B of the SRES (Special Report on Emissions Scenarios), Dyna-CLUE (Conversion of Land Use Change and its Effects) was applied for modeling of competition among land-use types in relation to socioeconomic and biophysical driving factors. For the study areas, 8 agricultural reservoirs were selected from 8 different provinces covering all around nation. The simulation results from 2010 to 2100 suggested future land-cover changes under the scenario conditions. For Madun reservoir in Gyeonggi-do, total decrease amount of paddy area was a similar amount of 'Base demand scenario' of Water Vision 2020 published by MLTMA (Ministry of Land, Transport and Maritime Affairs), while the decrease amounts of paddy areas in other sites were less than the amount of 'High demand scenario' of Water Vision 2020. Under A1B scenario, all the land-cover results showed only slight changes in irrigation areas of agricultural reservoirs and most of agricultural reservoir watersheds will be increased continuously for forest areas. This approach could be useful for evaluating and simulating agricultural water demand in relation to land-use changes.

• 한국농공학회논문집
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• 제56권6호
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• pp.19-29
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• 2014

The objectives of this study were to monitor and analyse water quality and soil property in paddy fields where untreated wastewater is irrigated. Three paddy fields where streamflow mixed with untreated wastewater has been irrigated (untreated wastewater district, UWD) were selected for monitoring, and five paddy fields in Yongin area (Yongin district, YID) where water from Idong agricultural reservoir (well-managed) has been irrigated were selected for comparative evaluation. Electronic conductivity (EC), suspended solids (SS), total nitrogen (T-N), total phosphorous (T-P), $NO_3-N$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$, total coliform (TC), fecal coliform (FC), and E. coli of the irrigation water in the UWD were significantly higher than those in the YID. Relatively high concentrations of EC, T-N, T-P, TC, FC, E. coli, copper (Cu), lead (Pb), zinc (Zn), and aluminium (Al) were shown in the irrigation water of the UWD especially during May to June. In general, the paddy soil in the UWD contained more Pb, Zn, and Cu than in the YID although the soil heavy metal contents in the UWD still meet the Korean soil contamination warning standards. No temporal trends in the heavy metal concentrations were found in paddy soils of the UWD. This study showed that the use of untreated wastewater to paddy fields has the possibility of negative impacts on water quality and soil, although long-term monitoring is needed to fully evaluate its effects.