• 한국농공학회논문집
• /
• 제49권2호
• /
• pp.3-13
• /
• 2007

The primary objective of this study was to compare water use efficiencies between subsurface drip irrigation and furrow irrigation. The uniformity of used drip lines was tested to determine if clogging would be a threat to the long-term success of a subsurface drip irrigation system. Three crops, cantaloupe, lettuce, and bell pepper, were grown in four plots for each irrigation system. Significantly less water was applied with subsurface drip irrigation than with furrow irrigation (29.5 % less for cantaloupe and 43.2 % less for bell poppet) in order to produce similar crop yields. Water use efficiencies with subsurface drip irrigation were significantly higher than those with furrow irrigation fur cantaloupe (P-value = 0.018) and bell pepper (P-value ${\leq}$ 0.001). Drip-irrigated lettuce, a shallow-rooted crop, had moderately higher water use efficiency during the first two seasons, while no difference was observed in the third season. After the experiment, the uniformity of the drip lines was 92.1 % on average and classified as good. The high values fur water use efficiency and uniformity indicate that subsurface drip irrigation can be a sustainable method for conserving irrigation water.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제22권3호
• /
• pp.18-26
• /
• 2017

The increasing frequency of droughts has been increasing the necessity of utilizing subsurface dams as reliable groundwater resources in areas where it is difficult to supply adequate agricultural water using only surface water. In this study, we analyzed the current status and actual conditions of five agricultural subsurface dams as well as the effect of obtaining additional groundwater from subsurface dams operated as one aspect of the sustainable integrated water management system. Based on the construction methods and functions of each subsurface dam, the five subsurface dams are classified into three types such as those that derive water from rivers, those that prevent seawater intrusion, and those that link to a main irrigation canal. The classification is based on various conditions including topography, reservoir location, irrigation facilities, and river and alluvial deposit distributions. Agricultural groundwater upstream of subsurface dams is obtained from four to five radial collector wells. From the study, the total amount of groundwater recovered from the subsurface dam is turned out to be about 29~44% of the total irrigation water demand, which is higher than that of general agricultural groundwater of about 4.6%.

• 한국작물학회지
• /
• 제61권4호
• /
• pp.264-269
• /
• 2016

본 연구는 무경운 재배법에 알맞은 비료종류 및 시비방법을 확립하고자 수행되었다. 주요 결과는 아래와 같다. 1. 지중관수를 이용한 시비가 관행시비 처리보다 경장, 경직경 및 협수가 높았으며 각 처리구별 개화시기를 비교시 관행시비 화학비료 처리구에서 7월 28일로 개화시기가 가장 빨랐다. 성숙기 생육특징과 개화시기를 비교해보면 지중관수를 이용한 시비방법이 작물의 생장에 효과적이었다. 2. 질소 이용량은 지중관수와 관행시비 간의 효율을 비교 시 지중관수를 이용한 시비가 관행시비에 비해 질소의 흡수가 월등히 많음을 알 수 있었다. 3. 인의 흡수량은 지중관수, 관행시비 모두 가축비료 시비보다 화학비료 시비에서 많은 양의 인이 흡수되었으며, 질소가 지중관수 시에 높게 흡수되는 것과는 달리 관행시비 시에 인이 높게 흡수되었다. 4. 원자흡광분석법을 통하여 각 시비방법, 비료종류별 칼리의 흡수량을 조사한 결과 인의 흡수량과 비슷한 양상을 보였으며, 지중관수, 관행시비 처리구 모두 가축비료에서 칼리의 흡수가 이루어지지 않았다. 5. 수확 후 수량을 비교한 결과 지중관수를 이용 할 때는 가축비료와 화학비료간의 유의성은 존재하지 않지만, 관행시비를 이용한 가축비료와 화학비료 시비에는 유의차가 있는 수준에서 수량이 감소하였다.

• 한국농공학회지
• /
• 제31권2호
• /
• pp.104-115
• /
• 1989

In an effort to clarify the wetted patterns of sandy loam soil under trickle irrigation conditions, the distance of wetted zone, infiltration capacity and soil wetted patterns, etc. were measured by gypsum block as soil moisture sensor located every 5 cm vertically and horizontaly in the soil bin under the such conditions as a). irrigation rates set to 2, 4, 6, 8 liters per hour b). total amount of water applied fixed to 14.62 liters per soil bin c) the hearing force of soil measured by plate penetrometer ranging from 1.04 to 1.22kg/cm$_2$ The results can be summarized as follows ; 1. The wetted distance in horizontal direction(H), the wetted distance in vertical direction(D), the horizontal infiltration capacity (iH) and the vertical infiltration capacity(in)could by explained as a function of time t. 2. The horizontal wetted distance (H) is explained by an exponetial function H= a$.$ t where b was found ranging from 021 to 026 under surface trickle irrigation, which was considered a lotlower than the classical value of 0.5 and these measurements were indifferent to the increasing irrigation rates. 3. As for the surface trickle irrigation where horizontal infiltration capacity(iH) is explained as iH = A $.$ t h, the coefficient A increases with respect to irrigation rates within the limits of 0.89~1.34. 4. In terms of surface trickle irrigation of the ratio of Dm Which is maximum vertical wetted distance to Hm, which is maximum horizontal wetted distance, found to be within range of 1.0 to 1.21. It was also noted that the value of Dm decreses when irrigation rates increases while the value of Hm changes the opposite direction. 5. The optimum location of sensors from emitter for surface trickle irrigation should he inside of hemisphere whose lateral radius is 28~30cm long and vertical radius is 10~12cm long. The distance between emitters should be within 60cm long. 6. In the study of vertical wetted distance( D) where D= a $.$ tb, the exponential coefficient b ranged from 0.61 to 0.75 in surface trickle irrigation, and from 0A9 to 0.68 for subsurface trickle irrigation. These measurements showed an increasing tendency to with respect to irrigation rates. 7. In case of vertical infiltration capacity( in), where iD= A $.$ t 1-h, the coefficient A for surface trickle irrigation found to be within range of 0.16 to 0.19 and did not show any relationships with varying degree of irrigation rates. However, the coefficient was varying from 0.09 to 0.22 and showed a tendency to increase vis-a-vis irrigation rates for subsurface trickle irrigation, in contrast. 8. In the observation of subsurface trickle irrigation, it was found that Dm/Hm ratio was within 1.52 to 1.91 and showed a decreasing tendency with respect to increasing rates of irrigation. 9. The location of sensors for subsurface trickle irrigation follows same pattern as above, with vertical distance from emitter being 10~17cm long and horizontal 22~25cm long. The location of emitter should be 50 cm. 10.The relationship between VS which is the volume of wetted soil and Q which is the total amount of water when soil is reached field capacity could be explained as VS= 2.914Q0.91and the irrigation rates showed no impacts on the above relationship.

• 한국토양비료학회지
• /
• 제45권5호
• /
• pp.683-689
• /
• 2012

본 연구는 시설 하우스 재배에서 지중관수 호스 간격 처리가 상추의 무기성분 함량과 흡수량, 수량, 관수량 및 토양화학성에 미치는 영향을 알아보기 위하여 수행되었다. 상추재배는 반촉성 및 억제재배를 하였으며 시험처리는 분수살수 처리와 지중 호스를 30 cm 깊이에 호스의 배치 간격이 각각 30, 40 및 50 cm 되도록 한 지중관수 처리를 포함하여 총 4처리를 하였다. 지중관수 처리에 의한 상추의 무기성분 함량은 처리간에 차이가 없으나 양분 흡수량은 호스 간격 50 cm 처리에서 가장 낮았다. 수량은 50 cm $\leq$ 분수살수 $\leq$ 40 cm $\leq$ 30 cm 순으로 많았고 관수량은 분수살수 처리가 가장 많았으며 지중관수 처리 간격이 넓을수록 적었다. 토양 양분함량 중 지표 하 10 cm에서 질산태 질소는 50 cm> 40 cm> 분수살수> 30 cm 처리 순으로 많았으며 치환성 칼리함량은 50 cm 처리에서, 마그네슘 함량은 40 cm에서 높았고 칼슘은 30 cm 처리에서 낮았다. 결과적으로 상추 재배에서 지상 분수살수와 지중 점적관수 30 cm 깊이에서 30~40 cm 간격 처리는 수량 차이가 없었으나 관수량은 지중관수에서 호스 간격이 넓을수록 적었다. 지중관수에서 작물의 수량 및 토양 중 양분 변화는 호스의 깊이와 점적기 및 호스간격, 토성에 따른 물의 이동과 작물의 양분 반응에 따라 차이가 있을 수 있어 보다 정밀한 연구가 필요한 것으로 생각되었다.

• Journal of Biosystems Engineering
• /
• 제14권2호
• /
• pp.128-136
• /
• 1989

The purpose of this study was to develop a computer operated automatic drip irrigation system for application in vinyl-house cultivation. The results can be summarized as follows: 1) The T-type ice compensation wire was used to measure the temperature. The voltage level measured up to 0.02 volt was used as input to an 8-bit A/D converter. 2) A specially devised tensiometer was used to content the watering system. When the needle of the pressure gauge reaches the lower threshold position it turns on the pumping system and turns off when it reaches higher threshold position. 3) In order to use the multiple gypsum blocks for one transducer, reed relays and a D/O board were used to make the sequential switching possible. 4) It was possible to automate the trickle irrigation system for the whole growth period of vinyl-house crops with the help of microcomputer. 5) In terms of furrow irrigation, the irrigation water consumption was the smallest, 2.8 times less than conventional method of surface trickle irrigation, 3.4 times less than subsurface trickle irrigation method. 6) In terms of productivity of cucumber, there was a drop in productivity when compared to furrow irrigation method, 7.2% for surface trickle irrigation, 27.4% for subsurface irrigation method.

• Journal of Mechanical Science and Technology
• /
• 제19권8호
• /
• pp.1582-1596
• /
• 2005

Groundwater flow and behavior have to be investigated based on heterogeneous subsurface formation since the homogeneity assumption of this formation is not valid. Over the past twenty years, stochastic approach and Monte Carlo technique have been utilized very efficiently to understand the groundwater flow behavior. However, these techniques require lots of computational and numerical efforts according to the various researchers' comments. Therefore, utilizing new techniques with much less computational efforts such as Artificial Neural Network (ANN) in the prediction of the stochastic behavior for the groundwater based on heterogeneous subsurface formation is highly appreciated. The current paper introduces the ANN technique to investigate and predict the stochastic behavior of a well draw down in a confined aquifer based on subsurface heterogeneous hydraulic conductivity. Several ANN models are developed in this research to predict the unsteady two dimensional well draw down and its stochastic characteristics in a confined aquifer. The results of this study showed that ANN method with less computational efforts was very efficiently capable of simulating and predicting the stochastic behavior of the well draw down resulted from the continuous constant pumping in the middle of a confined aquifer with subsurface heterogeneous hydraulic conductivity.

• 한국토양비료학회지
• /
• 제51권2호
• /
• pp.79-89
• /
• 2018

Subsurface drip irrigation (SDI) system is considered one of the most effective methods for water application. A 2-year field study was conducted to investigate the effect of SDI systems with various dripline spacing (0.7 or 1.4 m) and position (under furrow or ridge) on soybean (Glycine max L.) production at a sandy-loam soil in Miryang, South Korea. For 2016-2017, average grain yield in SDI irrigated plots, $3.16Mg\;ha^{-1}$, was statistically greater than rainfed irrigated plot ($2.63Mg\;ha^{-1}$). Soybean grain yield averaged $3.25Mg\;ha^{-1}$ for the 0.7 m dripline spacing and $3.07Mg\;ha^{-1}$ for the 1.4 m spacing for the two-year period compared to a rainfed irrigated average of $2.63Mg\;ha^{-1}$ for the same period. Soybean treated with SDI system had significantly greater values of normalized difference vegetation index and stomatal conductance, indicating that soybean plants in SDI plots had greater photosynthetic and stomatal activity due to the higher water availability in soil. Irrigation water use efficiency (IWUE) was greatest in the plot of 0.7 m spacing installed under ridge position than any other plot across growing season. Average soil water content in plots with 0.7 m dripline spacing was $0.21m^3\;m^{-3}$ at 5 cm depth layer, which was 45% greater compared to the plots with 1.4 m spacing, even though the gross irrigation amounts were greater in 1.4 m spacing plots. It is concluded that wide dripline spacing (1.4 m) is probably the more economical installation design for SDI system compared to 0.7 m spacing in this study soil because the initial cost for dripline may be reduced with wide spacing design, even though the IWUE is greater in the plot of 0.7 m dripline spacing.

• 대한원격탐사학회지
• /
• 제40권1호
• /
• pp.45-56
• /
• 2024

Faced with aging populations, declining resources, and limited agricultural productivity, rural areas in South Korea require innovative solutions. This study investigated the potential of drone-based vegetation indices (VIs) to analyze soybean growth patterns in open-field smart agriculture in Goesan-gun, Chungbuk Province, South Korea. We monitored multi-seasonal normalized difference vegetation index (NDVI) and the normalized difference red edge (NDRE) data for three soybean lots with different irrigation methods (subsurface drainage, conventional, subsurface drip irrigation) using drone remote sensing. Combining NDVI (photosynthetically active biomass, PAB) and NDRE (chlorophyll) offered a comprehensive analysis of soybean growth, capturing both overall health and stress responses. Our analysis revealed distinct growth patterns for each lot. LotA(subsurface drainage) displayed early vigor and efficient resource utilization (peaking at NDVI 0.971 and NDRE 0.686), likely due to the drainage system. Lot B (conventional cultivation) showed slower growth and potential limitations (peaking at NDVI 0.963 and NDRE 0.681), suggesting resource constraints or stress. Lot C (subsurface drip irrigation) exhibited rapid initial growth but faced later resource limitations(peaking at NDVI 0.970 and NDRE 0.695). By monitoring NDVI and NDRE variations, farmers can gain valuable insights to optimize resource allocation (reducing costs and environmental impact), improve crop yield and quality (maximizing yield potential), and address rural challenges in South Korea. This study demonstrates the promise of drone-based VIs for revitalizing open-field agriculture, boosting farm income, and attracting young talent, ultimately contributing to a more sustainable and prosperous future for rural communities. Further research integrating additional data and investigating physiological mechanisms can lead to even more effective management strategies and a deeper understanding of VI variations for optimized crop performance.

• 생물환경조절학회지
• /
• 제18권3호
• /
• pp.225-231
• /
• 2009

지표관수와 비교하여 지중관수 및 지중관수 시 공기주입의 효과를 검토하고자 '녹광' 풋고추를 온실 내에서 토양재배(silty loam)하여 관수효율, 토양특성, 과실 생육 및 수량 등을 조사하였다. 관수방법은 관수호스를 이랑당 2열 배열하되 지표관수는 토양표면, 지중관수는 지표 20cm 아래에 설치하였고, 공기주입은 air compressor를 이용하여 낮 동안에 시간당 3분간 주입하였다. 관수는 콘트롤러, 전자식 토양수분장력센서 등을 이용, 토양수분에 기초한 자동관수를 실시하였는데, 관수개시점은 -20kPa, 관수종료점을 -10kPa로 설정하여 관리하였다. 그 결과, 토양수분의 감소속도가 지표 관수에 비해 지중관수와 지중관수 +공기주입이 늦었으며, 관수량도 지중관수가 지표환수에 비해 지표면에서의 증발 감소 등으로 약 30% 적었다. 표토층의 EC 및 무기이온함량은 지표관수에 비해 지중관수나 지중관수 +공기주입이 낮은 수준이었다. 뿌리의 발달은 지표관수에 비해 지중관수+공기주입한 것이 가장 좋았는데, 특히 뿌리가 길고 세근의 발달이 많았다. 이로 인해 풋고추 수량이 지표관수에 비해 지중관수가 22%, 지중관수 +공기주입이 30% 각각 증가되었다.