• 한국관개배수논문집
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• 제2권2호
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• pp.27-36
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• 1995

Changes of meteorology, hydrological mechanism and discharge phenomena by the regional development have caused many technical, social and economical problems. Therefore, the regional development neglecting such changing parameters can provide considerable

• 한국농공학회지
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• 제37권6호
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• pp.103-111
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• 1995

Drought index calculation based on the principal hydrological parameters, such as rainfall and reservoir storage, can estimate the duration and intensity of drought in irrigation reservoirs. It is difficult to build up a drought criteria since the conditions change variously by the reliability of rainfall. Because of the increasing water demands, it is urgent to prepare a generalized positive countermeasure to overcome drought. Water demands can at calculated but the estimation of drought characteristics, and the effective water management method can be established. The purpose of this study is to obtain a drought index and build up a data-base on the reservoir basins for establishing the fundamental hydrological data-base. This Index can observe the behavior of the WSI(Water Supply Index) and the component indices. The results summarized through this study are as follows. 1. WSI value of zero does not correspond to 100% in average due to the skewness in the probability distributions. 2. WSI is not a linear index; that is, given change in terms of water volume or percentage of average does not result in a proportional change on the WSI scale. 3. WSI is not always between the reservoir and the rainfall index in magnitude. This is only true if the component indices are of opposite sign. If they are of the same sign, the SWSI will often have a mangitude greater than either of the component indices. This is easily understood, because the concurrence of extreme values of the same sign for the two components is rarer than the occurrence of extreme values for either of the two components individually.

• 한국농공학회논문집
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• 제56권6호
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• pp.45-53
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• 2014

This study presents a system dynamics modeling approach to simulate daily streamflow in a watershed including wastewater treatment plant which contributes to irrigation water supply. The conceptual system dynamics model considering the complex and dynamic hydrological processes in the watershed was developed. The model was calibrated and validated each for two years based on observed flow data. Model performances in terms of $E_{NS}$, RSR, PBIAS, and $R^2$ were 0.64, 0.60, -3.6 %, and 0.64 for calibration period, and 0.66, 0.58, -2.6 %, and 0.66 for validation period, respectively, showing an applicability on generating the daily streamflow. System dynamics modeling approach could help better understand the hydrological behavior of the watershed being reused wastewater for agriculture, by providing graphical dynamics of the hydrological processes as well as conventional rainfall-runoff model results.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.1-7
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• 2007

New Zealand is a hydrologically diverse and active country. This paper presents an overview of the major hydrological issues and problems facing New Zealand and provides examples of some the research being undertaken to solve the problems. Fundamental to any environmental decision making is the provision of good quality hydrometric data. Reduced funding for the national hydrometric network has meant a reduction in the number of monitoring sites, the decision on how to redesign the network was made using information on geographic coverage and importance of each site. New Zealand faces a major problem in understanding the impacts of rapid land use change on water quantity and quality. On top of the land use change is overlain the issue of agricultural intensification. The transfer of knowledge about impacts of change at the small watershed scale to much larger, more complex watersheds is one that is attracting considerable research attention. There is a large amount of research currently being undertaken to understand the processes of water and nutrient movement through the vadose zone into groundwater and therefore understanding the time taken for leached nutrients to reach receiving water bodies. The largest water management issue of the past 5 years has been based around fair and equitable water allocation when there is increasing demand for irrigation water. Apart from policy research into market trading for water there has been research into water storage and transfer options and improving irrigation efficiency. The final water management issue discussed concerns the impacts of hydrological extremes (floods and droughts). This is of particular concern with predictions of climate change for New Zealand suggesting increased hydrological extremes. Research work has concentrated on producing predictive models. These have been both detailed inundation models using high quality LIDAR data and also flood models for the whole country based on a newly interpolated grid network of rainfall.

• 한국농공학회논문집
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• 제58권5호
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• pp.19-28
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• 2016

This study was to design the optimal locations of the water level monitoring to quantify the agricultural water use in irrigation area supplied from an agricultural reservoir. In most of agricultural areas without TM/TC (Tele-Monitoring and Tele-Control) or monitoring network, irrigation water have been supplied on conventional experience and agricultural reservoir have been operated based on the operating simulation results by HOMWRS (Hydrological Operation Model for Water Resources System). Therefore, this study quantified the amount of agricultural water use in an irrigation area (Musu Reservoir, Jincheon-gun) by establishing water level monitoring network and analyzed the agricultural water saving effect. According to the evaluation of the economic values for water saving effect, the saving agricultural water of 1.7 million ton was analyzed to have economic values of 0.85 million won as water for living, and 1.78 million won as water for industrial use. It is identified to secure economic feasibility of the new water monitoring network by establishing one monitoring point in the entrance, irrigation area and endpoint through the economic analysis.

• 한국농공학회논문집
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• 제54권3호
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• pp.29-36
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• 2012

This study was carried out to investigate the runoff characteristics in paddy field using livestock compost fertilizer. Irrigation, runoff and water quality data in the paddy field were analyzed periodically from May to September in 2011. The observed amounts of rainfall, irrigation, runoff for the experimental paddy field during the irrigation period were 1,148.2 mm, 523.9 mm, and 344.7 mm, respectively. T-N concentrations ranged from 2.28 mg/L to 11.75 mg/L, which was generally higher than the quality standard of agricultural water (1.0 mg/L). T-P concentrations ranged from 0.018 mg/L to 0.241 mg/L and the average was 0.122 mg/L. The runoff loads of T-N and T-P were 15.7 kg/ha and 0.4 kg/ha, respectively. The runoff pollutants loadings in T-N and T-P in this study were much lower values than the loads of T-N and T-P from the paddy field presented by others' studies. We are considering that these results were affected by rainfall as well as hydrological condition, irrigation water, fertilizer application, rice straw and plowing.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.174-177
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• 2004

Differential interferometric phases from JERS-1 L­band data sets show spatial variation of path-length ranging from a few mm to several cm. The variation may be caused by changes in soil moisture contents, i.e. variation of penetration depth and the swelling of soils. Although the amount of total effect caused by soil moisture is not measurable, it is clear that the soil moisture according to precipitation is another factor to be considered in DInSAR analysis. We also discuss DInSAR characteristics in a rice paddy according to irrigation conditions, and discrimination of hydrological features such as stream channels and watershed boundaries by applying DInSAR technique.

• 한국관개배수논문집
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• 제14권2호
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• pp.225-235
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• 2007

The shape of streamflow hydrograph during the early period of spring is very much controlled by the area and depth of snow cover especially in mountainous area. When we simulate the streamfolw of a watershed snowmelt, we need some information for snow cover extent and depth distribution as parameters and input data in the hydrological models. The purpose of this study is to suggest an extraction method of snow cover area and snow depth distribution using Terra MODIS image. Snow cover extent for South Korea was extracted for the period of December 2000 and April 2006. For the snow cover area, the snow depth was interpolated using the snow depth data from 69 meteorological observation stations. With these data, it is necessary to run a hydrological model considering the snow-related data and compare the simulated streamflow with the observed data and check the applicability for the snowmelt simulation.

• 한국농공학회지
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• 제35권2호
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• pp.104-115
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• 1993

The objectives of this paper were to develop predictive equations for reservoir deposits and watershed sediment yields based on sediment survey data for irrigation reservoirs. Hundred reservoirs of various sizes, which have the surveyed data for sediment deposits, were chosen and fourteen watershed physiological and hydrological parameters were investigated. Correlationships between watershed parameters and sediment deposits were investigated and a best fit regression equation was derived, which may be applied for estimating reservoir sediment deposits. The sediment deposits were converted to the watershed sediment yields by applying the trap efficiencies and specific weights. The resulting sediment yields were related to watershed parameters and an empirical predictive equation was also proposed that may be used for rough estimations of watershed sediment yields.

• Applied Biological Chemistry
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• 제43권4호
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• pp.285-290
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• 2000

본 연구는 논에서 강우에 의한 질소와 인산의 유출특성을 조사하였다. 이를 위하여 농업이외의 오염원이 비교적 적은 전라북도 진안군 마령면 평지리 일대 $5,000\;m^2$의 논을 시험포장으로 선정하여 1997년 5월 1일부터 1998년 4월 30일까지 12개월 동안 유출수 중 질소와 인의 시기별 함량변화 및 논에서의 유출수문 자료를 수집하였다. 논에서의 평균 유효유량은 관개기간 동안에 77.0 mm, 비관개기간 동안에는 21.2 mm로 나타났으며, 초기유출우량은 관개기간 동안 6.3-33.7 mm의 범위로 평균 12.9 mm, 비관개기간 동안 5.9-12.5 mm의 범위로 평균 9.2 mm로 산정되었다. 유출계수는 관개기간 중 0.59-1.36, 비관개기간 동안에는 0.57-0.86의 범위를 나타내었다. 관개기간과 비관개기간 사이에 영양물질의 유출특성에 차이가 없는지를 조사한 결과, 질소원과 인산원은 시기별로 유출량의 차이가 나타나지 않은 반면, 부유물질은 시기별로 차이를 나타내고 없었다. 논에서 강우-유출 중 발생하는 유출수량을 이용한 유출부하량 예측 결과, 질소원은 유출부하량 예측이 가능하였지만, 입자태 성분의 형태로 유출이 발생하는 부유물질과 전인은 약간의 오차가 발생하였다.