• 제목/요약/키워드: Soil water potential

검색결과 810건 처리시간 0.029초

Mapping Within-field Variability Using Airborne Imaging Systems: A Case Study from Missouri Precision Agriculture

  • Hong, S.Y.;Sudduth, K.A.;Kitchen, N.R.;Palm, H.L.;Wiebold, W.J.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1049-1051
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    • 2003
  • This study investigated the use of airborne image data to provide estimates of within -field variability in soil properties and crop growth as an alternative to extensive field data collection. Hyperspectral and multispectral images were acquired in 2000, 2001, and 2002 for central Missouri experimental fields. Data were converted to reflectance using chemically-treated reference tarps with known reflectance levels. Geometric distortion of the hyperspectral pushbroom sensor images was corrected with a rubber sheeting transformation. Statistical analyses were used to relate image data to field-measured soil properties and crop characteristics. Results showed that this approach has potential; however, it is important to address a number of implementation issues to insure quality data and accurate interpretations.

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유기물의 토양 개량 효과 측정 (The Measurement of Soil Conditioning Effects of Organic Materials)

  • 주영규
    • 아시안잔디학회지
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    • 제7권1호
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    • pp.13-18
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    • 1993
  • Much attention has been given recently to solve the environmental contamination in golf courses Changing to culture practice rather than chemical practice that depends on pesticides and fertilizers is a hot issue in golf courses or grasslands. Organic soil conditioners improve soil-plant envirormental conditions rich in physical properties. In this study, measuring systems to evaluate soil conditioning effects were set up for on-site purpose. After establishing the methodology for evaluating soil conditioner effects, 2 kinds of organic conditioners were rested for examination. The systems for the methodology included a set of simulating equipment for field capacity, an impact type soil column compactor, and an infiltration-percolation system. Test results using the systems showed bulk density and infiltration rate of mixed soil were decreased at highter rates of conditioner, but total porocities were increased. Increased porocities were most capillary pore space which has a positive effect on soil water potential. The systems and methodology in this study seem to have an efficiency to measure the effects of soil conditioner on site purpose.

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인공산성빗물이 소나무의 조직, 수분수지 및 생장에 미치는 영향 (Effects of Simulated Acid Rain on Histology, Water Status and Growth of Pinus densiflora)

  • 이창석;길지현;유영한
    • The Korean Journal of Ecology
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    • 제21권2호
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    • pp.117-124
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    • 1998
  • To clarify the effects of acid precipitates on histological damage, water status, and growth of Pinus densiflora green house experiment applyin simulated acid rain was carried out. Contact angle of water droplet on needles of P. densiflora seedlings treated with simulated acid rain of different pHs simulated acid rain was, the more rapid transpiration was. Leaf water potential after water withdrawal was also reduced rapidly in proportion to acidity of simulated acid rain. Height growth of P. densiflora seedlings treated with simulated acid rain of pH 2 decreased, while growth of seedlings treated with that of pH 3 and 4 increased comparing with that treated with normal rain of pH 5.6. pH of cultivated soil in pH 2 plot was acidified with the amount of simulated acid rain applied but that in pH 3 and 4 plots did not show any directional change. From those results, it could be interpreted that decrease of height growth in pH 2 plot was originated from multiple effects of water deficit from rapid transpiration and soil acidification. On the other hand, increased of height growth in pH 3 and 4 plots would be originated from the supply of N and S included in simulated acid rain.

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상수도 배관용 무선 원격 부식모니터링 시스템 (The Remote Wireless Corrosion Monitoring System for Water Pipeline)

  • 하태현;배정효;이현구;하윤철;김대경
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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    • pp.637-640
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    • 2003
  • The owner of water pipeline has a burden of responsibility for the protection of corrosion and the prevention against leakage of water. So, they have been installed a CP(Cathodic Protection) System in oder to protect corrosion. And they also have been measured and analyzed the data about P/S(Pipe to Soil) potential of water pipeline. The P/S potential is basic data of evaluation for water pipeline corrosion. In this paper, results of development about remote wireless corrosion monitoring system for water pipe line are presented briefly.

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취나물류의 물질생산과 광합성특성에 관한 연구 II. 수분스트레스하에서 고온 및 저온처리가 취나물류의 광합성속도에 미치는 영향 (Study on Matter Production and Phothsynthetic Characteristics in Wild Vegetable(Chwinamul))

  • 조동하
    • 한국자원식물학회지
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    • 제11권3호
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    • pp.307-314
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    • 1998
  • The response of water stree under high and low temperatures, was shown differently according to the longer the suspension period of water supply. Leaf photosynthetic rate(LPS), leaf water potential(WP), relative leaf water content and relative soil water content were lower. At the higher temperatures, the percentate of reduction in LPS and WP was greater than at low temperatures. It is suggested that evaporation rate should be higher in the high temperature than the lower temperature. Also leaf water potential was lower at high temperature than at low temperature. After the 9 th day of treatment , LSP was remarkably reduced at high temperature, but the reduction of LPS was not significant at low temperature. Solidago virga-aurea var. asiatic that maintained LPS of 3rd day after treatment was more strong than other varieties at low temperatures. The silting and curling of leaves were observed symptoms of stress on the 9th day at the both temperatures. The leaves of aster scaber and Ligularia fischeri turned red on the 9th day after treatment at low temperature.

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실내오염물질 정화를 위한 수생식물의 이용가능성에 관한 연구 (A Study on Potential of Aquatic Plants to Remove Indoor Air Pollutants)

  • 박소영;김정;장영기;성기준
    • 한국환경복원기술학회지
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    • 제8권5호
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    • pp.1-9
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    • 2005
  • This study was conducted to investigate the effect of aquatic plant as a botanical air purification on the indoor air pollution by formaldehyde. Three aquatic plants such as Eichhornia crassipes, Cyperus alternifolius, Echinodorus cordifolius, were selected for this study and they were placed in the artificially contaminated chamber under laboratory condition. The results showed that all three plants could remove the formaldehyde from the contaminated air system effectively. Reduction in the formaldehyde levels by Eichhornia crassipes, which is the floating plant, might be associated with the factors of plant and water. Reduction in the formaldehyde levels by Cyperus helferi and Echinodorus cordifolius, which were emergent plant, was due to the complex effect of plant, soil medium and water. In aquatic plant system, dissolution, microbial degradation in rhizosphere, uptake through root and shoot, sorption to soil and shoot, hydrolysis are known as the main mechanisms of water soluble pollutants in the given system. The advantages of indoor air quality control system using aquatic plants can be; 1) various purifying mechanisms than foliage plants, 2) effective for decontamination of water soluble pollutants; 3) easy for maintenance; 4) diverse application potential. Therefore it was suggested from the results that indoor air control system of aquatic plants should be more effective for reduction of indoor air pollutants.

Soybean Growth and Yield as Affected by Spacing of Drainage Furrows in Paddy Field

  • Cho, Jin-Woong;Lee, Jung-June;Oh, Young-Jin;So, Jung-D.;Won, Jun-Yeon;Kim, Chang-Ho
    • 한국작물학회지
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    • 제51권1호
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    • pp.26-31
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    • 2006
  • This study was conducted to determine the optimum number of inter-rows according to distance of drainage furrow (DF) for running-off excessive-water stress (EWS) in paddy field. The most soil water potential was shown in high ridge (distance of DF by 70 cm) cultivation and the soil water potential showed increasing tendency in over four inter-rows cultivation by DF. The growth of soybean reduced by extended inter-row and its reducing level was high, especially, over four inter-rows (DF distance by 2.8 m) because of EWS. The photosynthetic rate decreased in the more extensive field by distance of DF at V5 and R2 stages, especially, in over four interrows cultivation. Also, root activity decreased at wider DF. The yield was reduced with wider distance of DF more extensively, the highest yield of 270 g per $m^2$ at the every row, but yield showed decreasing tendency at over the $4^{th}$ row (2.8 m) cultivation. Soybean cultivation in paddy field could be founded with DF of every other or $4^{th}$ row.

Rice Yield Response to Biochar Application Under Different Water Managements Practices

  • Jung, Won-Kyo
    • 한국토양비료학회지
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    • 제45권1호
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    • pp.16-19
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    • 2012
  • Increasing rice grain yield is critical for feeding rapid increasing of Asian population. However, global warming effect may be negative for sustainable rice production. Therefore it is essential to develop technologies not only for increasing grain yield but also for reducing global warming effect. Biochar, which is carbonized biomass, has a great potential of carbon sequestration and soil quality improvement, which can contribute grain yield increasing. In this study, rice yield responses to biochar application on the rice cropping system were evaluated with field experiments under different water management practices at the research farm of the University of Missouri-Columbia Delta Research Center, Portageville, MO. Biochar (i.e., $4Mg\;ha^{-1}$) was produced using field scale pyrolyzer and incorporated into the field 4 months prior to planting. Rice was grown under three different water management practices. Result showed that no significant yield difference was found in the biochar application plots compared to rice hull and control plots from the 2 years field study at the very fertile soil. However, rainfed management results in severe reduction of yield. Research concludes that the biochar application does not significantly influence on rice yield increasing especially for very fertile soils.

Implementation of Polyacrylamide in the Agricultural Environment and its Recent Review

  • Choi, Yonghun;Kim, Minyoung;Kim, Youngjin;Jeon, Jonggil;Seo, Myungchul
    • 한국토양비료학회지
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    • 제49권5호
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    • pp.440-448
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    • 2016
  • Nonpoint sources of pollution (NPS) is defined as diffuse discharges of pollutants (e.g., nutrient, pesticide, sediment, and enteric microorganism) throughout the natural environment and they are associated with a variety of farming practices. Previous studies found that water soluble anionic polyacrylamide (PAM) is one of the highly effective measures for enhancing infiltration, reducing runoff, preventing erosion, controlling nonpoint source of pollutants, and eventually protecting soil and water environment. Potential benefits of PAM treatment in agricultural soil and water environments have been revealed by many research and they include low cost, easy and quick application, and suitability for use with other Best Management Practices (BMPs) for NPS control. This study reviews the various applications of PAM and discusses its further potentials in agricultural environment.

복숭아나무의 엽온 및 작물수분스트레스 지수를 이용한 수분스트레스 평가 (Evaluation of Water Stress Using Canopy Temperature and Crop Water Stress Index (CWSI) in Peach Trees)

  • 윤석규;김성종;남은영;권정현;도윤수;송승엽;김민영;최용훈;김기석;신현석
    • 생물환경조절학회지
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    • 제29권1호
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    • pp.20-27
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    • 2020
  • 본 연구는 적외선 열 영상 장치를 이용하여 2년생 '유미' 복숭아나무의 토양수분 수준에 따른 엽온 및 CWSI를 분석하여 수분스트레스 측정 가능성을 검토하였다. 엽온은 대기온도와 유사한 일변화를 보이며 낮 시간대에는 대기온도보다 높은 양상을 보였다. 엽온은 전일(24시간) 기준으로 대기온도(r2 =0.95), 일사량(r2 =0.74), 상대습도(r2 =-0.88)와 모두 높은 상관계수를 나타났다. 또한 토양수분장력은 낮 시간대(11~16시)에 엽온(r2 =-0.57), 엽-대기온도차(r2 =-0.71), CWSI(r2 =-0.72)와 높은 부의상관을 나타냈다. CWSI와 엽온, 엽-대기온도차의 상관계수는 24시간 기준으로 매우 높았고(r2 =0.90, r2 =0.92), CWSI와 토양수분장력의 상관분석에서 24시간 기준으로는 상관관계가 낮았으나(r2 =-0.27), 낮 시간대(11~16시)에는 상관관계가 매우 높았다(r2 =-0.72). CWSI (y)와 토양수분장력(x)의 상관관계 결정계수(r2 )는 11~12시간대에 가장 높았으며(r2 =0.68), 이때 회귀식은 y = -0.0087x + 0.14로 조사되었다. 일반적인 토양수분스트레스 시점인 -50 kPa에 해당되는 CWSI는 0.575로 계산된다. 따라서 적외선 열 영상 장치를 이용한 엽온 및 CWSI는 토양수분장력에 대해 높은 상관계수를 나타낸 것으로 보아 복숭아나무의 수분스트레스 진단에 유용하게 활용할 수 있을 것으로 예상된다.