This study analyzed the impact of greenhouse cultivation area and groundwater level changes due to the water curtain cultivation in the greenhouse complexes. The groundwater observation data in the Miryang study area were used and classified into greenhouse and field cultivation areas to compare the groundwater impact of water curtain cultivation in the greenhouse complex. We identified the characteristics of the groundwater time series data by the terrain of the study area and selected the optimal model through time series analysis. We analyzed the time series data for each terrain’s two representative groundwater observation wells. The Seasonal ARIMA model was chosen as the optimal model for riverside well, and for plain and mountain well, the ARIMA model and Seasonal ARIMA model were selected as the optimal model. A suitable prediction model is not limited to one model due to a change in a groundwater level fluctuation pattern caused by a surrounding environment change but may change over time. Therefore, it is necessary to periodically check and revise the optimal model rather than continuously applying one selected ARIMA model. Groundwater forecasting results through time series analysis can be used for sustainable groundwater resource management.
Improvement of the Integrated Management System of Agriculture, Livestock and Food Statistics Data for Maintaining Information Consistency
위성승 Wee Seong Seung , 윤서일 Yoon Seo Il , 서정훈 Seo Jung Hun , 신용태 Shin Yong Tae
In the past, the Ministry of Agriculture, Food, and Rural Affairs (MAFRA) conducted research into and production of agricultural statistics. As a result of organizational changes, these responsibilities were transferred to Statistics Korea in 1998 and 2008. So, the MAFRA managed data without a formal system for managing data and statistical information. The demand for a foundation to improve the usefulness of agri-food statistics has recently increased due to the necessity for basic data representing the realities of rural and agricultural areas. This is especially true for field-oriented agricultural administration. This study aims to propose a strategy for the systematically integrated administration of dispersed data and statistical information. It served as the foundation for the integrated management of distributed administrative and statistical data.
A Study on the Potential of Agricultural Water and Environmental Flow Supply according to Regulating Lower Control Storage Rate for the Irrigation Reservoir
정지연 Jeong Jiyeon , 정민혁 Jeung Minhyuk , 범진아 Beom Jina , 박민경 Park Minkyeong , 이재남 Lee Jaenam , 유승환 Yoo Seung-hwan , 윤광식 Yoon Kwang-sik
A Study on the Potential of Agricultural Water and Environmental Flow Supply according to Regulating Lower Control Storage Rate for the Irrigation Reservoir
정지연 Jeong Jiyeon , 정민혁 Jeung Minhyuk , 범진아 Beom Jina , 박민경 Park Minkyeong , 이재남 Lee Jaenam , 유승환 Yoo Seung-hwan , 윤광식 Yoon Kwang-sik
While the main purpose of irrigation reservoirs is to supply agricultural water, the needs of environmental flow and flood control has been expanded. The agricultural reservoirs have been operated in the form of carry-over system until now. Therefore, the supply of agricultural water is difficult when the storage rate is not sufficiently secured after large volume of irrigation. In addition, there are regulation of the upper storage rate for some large reservoirs during the flood season, but lower storage rate is not regulated. Accordingly, this study aims to evaluate the capacity of agricultural water and environmental flow supply by setting the management lower storage rate of reservoir. The changes in the supply of agricultural and environmental flow was simulated according to the three different regulating lower storage rate scenarios. As a result, it was judged effective in terms of water supply managing the lower storage rate up to 30% when the initial storage rate of farming period is above annual average for the Naju reservoir considering existing water management practice. If the lower storage rate would have been controlled above 30%, the supply of agricultural water might be increased and non-effective discharge amount would be decreased compared to other scenarios during dry period of 2016-2018.
Assessing the Unit Load Reduction Equation of Drainage Outlet Raising Management in Paddy Fields
김동현 Kim Dong-hyeon , 오흥근 Oh Heung-keun , 장태일 Jang Taeil , 함종화 Ham Jong-hwa
The DOR (Drainage outlet raising) in the paddy field has been suggested as one of the most important best management practices for the TMDL (Total maximum daily load) management in the technical guidelines by the NIER (National institute of environmental research). However, this method is underestimated and is not well adopted by local governments for the TMDL. The purpose of this study is to evaluate the unit load reduction equation according to the application of DOR in order to expand this equation. The original equation in the guideline was derived using the HSPF (Hydrological Simulation Program-Fortran) model for 1 year in Changnyeong. We analyzed the reduction effect of the original equation application by collecting additional long-term monitoring data from the Buan, Icheon, Iksan, and Jeonju. When comparing the reduction loads between the original equation and monitoring results, the evaluation results of the original equation were 11% of the monitoring analysis results, which was underestimated. This means that the original equation needs to be improved. For assessing the equation, the HSPF Paddy-RCH model was established according t o t he NI ER guideline and evaluated for applicability. The performance results of the model showed a reasonable range by the statistical criteria. Modified equations 1 and 2 were proposed based on the monitoring and modeling results. Modified equation 1 was the method of modifying the original equation’s main factors, and modified equation 2 was the method of applying the non-point pollution reduction efficiency according to the rainfall class using the long-term modeling results. At the level of 58.6∼64.6% of monitoring data, the difference between them could be further reduced compared to the original equation. The suggested approach will be more reasonable and practicable for decision-makers and will contribute to the TMDL management plans.
Surface Image Analysis for Evaluating Porosity and Permeability Coefficient of Permeable Concrete Block
조상범 Jo Sangbeom , 손영환 Son Younghwan , 김동근 Kim Donggeun , 전지훈 Jeon Jihun , 김태진 Kim Taejin
The increase of impermeable area ratio is causing hydrologic cycle problems in urban areas and groundwater depletion in rural areas, permeable pavements are getting attention to expand permeable areas. The performance of the permeable concrete block pavement, which is part of the permeable pavement, is greatly affected by the porosity. In addition, the permeability coefficient is a major factor when designing permeable concrete block pavement. Existing porosity and permeability test methods have problems such as uneconomical or poor field applicability. The object of this study was to develop a methodology for evaluating porosity and permeability coefficient using a surface image of a permeable concrete block. Specimens are manufactured with various porosity ranges and porosity and permeability tests are performed. After surface image preprocessing, normalization and binarization methods were compared. Through this, the method with the highest correlation with the lab test result was determined. From the results, the PDR (pore determined ratio) was obtained. Simple linear regression analysis is performed with PDR and lab test results. The results showed a high correlation of R2 more than 0.8, and the errors were also low.
Analysis of the Emergency Water Supply Capacity in Agricultural Reservoirs Using K-HAS and Ratio Correction Factors
김하영 Kim Hayoung , 이상현 Lee Sang-hyun , 나라 Na Ra , 주동혁 Joo Donghyuk , 유승환 Yoo Seung-hwan
As the frequency of drought increases due to climate change, water scarcity in agriculture would be a main issue. However, it seems difficult to solve the water scarcity by securing alternative water sources. The aim of this study is to analyze optimal water supply capacity of agricultural reservoir for emergency operation connecting reservoirs and dams. First, we simulated the water storage of agricultural reservoir playing the role emergency water supplier to other water facility such as dams and other reservoirs. In particular, the results of simulation of water storage through K-HAS model was calibrated using the optimization process based on ratio correction factors of outflow and inflow. Finally, the optimal amount of water supply securing water supply reliability in emergency interconnection operation was analyzed. The results of this study showed that Janchi reservoir could supply 12.8 thousand ㎥/day maintaining 90 % water supply reliability. The result of this study could suggest the standard for connecting water facilities as emergency water supply.
Analysis of Irrigation Amounts and Soil Volumetric Water Contents by Irrigation Method in Saemangeum Reclaimed Tideland
손재권 Son Jae-gwon , 윤상원 Yoon Sang-won , 송재도 Song Jae-do
This study was conducted to analyze changes of irrigation water and soil volumetric water content by irrigation method of field soil in Saemangeum reclaimed tideland. The main test irrigation methods was surface drip irrigation, sprinkler irrigation, and sub drip irrigation. In addition, the correlation between irrigation amounts and crop yield by irrigation method was investigated. For soil volumetric water contents increases by 25%, surface drip irrigation took 1.5 hour, sprinkler irrigation took 2.0 hours, and sub drip irrigation took 3.0 hours. As a result of analyzing the irrigation amounts according to the yield, the surface drip irrigation was 2.66 mm/day in the seedling stages, 3.31 mm/day in the vegetative growth stages, and 5.09 mm/day in the flowering stages. Sprinkler irrigation was 2.90 mm/day in the seedling stages, 3.87 mm/day in the vegetative growth stages, and 7.11 mm/day in the flowering stages. Sub drip irrigation was 2.42 mm/day in the seedling stages, 3.09 mm/day in the vegetative growth stages, and 4.87 mm/day in the flowering stages. It was analyzed that there was a statistically significant difference in irrigation amounts by fresh weight and irrigation method (F=4.002, p=0.022), and irrigation amounts by dry weight and irrigation method (F=3.499 p=0.034). Surface drip irrigation was judged to be more appropriate than sprinkler irrigation or sub drip irrigation for field crops in Saemangeum reclaimed land.