• 제목/요약/키워드: Water Deficit

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재배환경에 따른 청예수수의 생산성에 관한 연구 5. 청예용 수수-수단그라스 교잡종의 생육시기별 수분부족이 재생수량 및 영양가에 미치는 영향 (Studies on the Productivity of forage Sorghum under the Different Cultural Environment 5. Effects of Water Deficit at Different Growth Stages on Regrowth, Yield and Nutritional Value of Sorghum-Sudangrass Hybrid)

  • 김영두;박호기;신만균
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 1989년도 추계 학술대회지
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    • pp.52-53
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    • 1989
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NDVI를 이용한 가뭄발생지역 검출 및 부족수분량 산정 (Drought Detection and Estimation of Water Deficit using NDVI)

  • 신사철;김경탁;김주훈;박정술
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2006년도 학술발표회 논문집
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    • pp.1201-1205
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    • 2006
  • 본 연구의 목적은 낙동강 권역을 대상으로 가뭄지역을 검출하고 부족수분량을 산정하는 방법을 개발하는 것이다. 위성자료는 임의 지점에 대하여 지속적이고 반복적인 관측 자료를 제공하므로 가뭄 감시를 위해 유용하게 사용될 수 있다. 본 연구에서는 증발산량과 정규식생지수(Normalized Difference Vegetation Index: NDVI)가 밀접한 상관성이 있는 점에 착안하여 MODIS 영상으로부터 얻어진 NDVI와 기상자료 중 기온자료를 이용하여 증발산량을 산정하는 간편법을 제안하였다. 또한, 가뭄 분석을 위해 위성자료로부터 얻어진 증발산량 자료를 이용하여 기후학적 물수지 모형에 의해 부족수분량을 산정하여 물부족의 심도를 파악하였다. 본 연구의 결과로서 가뭄 분석에 있어서 위성영상의 활용이 대단히 유용하다는 것을 보여주고 있다.

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Seasonal changes in pan evaporation observed in South Korea and their relationships with reference evapotranspiration

  • Woo, Yin San;Paik, Kyungrock
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2017년도 학술발표회
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    • pp.183-183
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    • 2017
  • Pan evaporation (Epan) is an important indicator of water and energy balance. Despite global warming, decreasing annual Epan has been reported across different continents over last decades, which is claimed as pan evaporation paradox. However, such trend is not necessarily found in seasonal data because the level of contributions on Epan vary among meteorological components. This study investigates long-term trend in seasonal pan evaporation from 1908 to 2016 across South Korea. Meteorological variables including air temperature (Tair), wind speed (U), vapor pressure deficit (VPD), and solar radiation (Rs) are selected to quantify the effects of individual contributing factor to Epan. We found overall decreasing trend in Epan, which agrees with earlier studies. However, mixed tendencies between seasons due to variation of dominant factor contributing Epan were found. We also evaluated the reference evapotranspiration based on Penman-Monteith method and compared this with Epan to better understand the physics behind the evaporation paradox.

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The water-energy-food resources and environment: Evidence from selected SAARC countries

  • Mansoor, Abdul;Sultana, Baserat;Shafique, Saima;Zaman, Khalid
    • Advances in Energy Research
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    • 제6권1호
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    • pp.1-15
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    • 2019
  • The objective of the study is to examine the relationship between water resources, energy demand, food production, and environmental pollutants in selected SAARC nations, namely, Bangladesh, India, Pakistan, and Sri Lanka, during the period of 1990-2016. The results show that water, energy, and food (WEF) resources substantially affected air quality in the form of high mass carbon emissions, fossil fuel energy demand, methane discharges, nitrous oxide emissions, and greenhouse gas emissions in these countries. Food production and food deficit largely increase $CO_2$ emissions due to unsustainable production and malnutrition, while land use under cereal production increases $CH_4$ and $N_2O$ emissions. Electricity production escalates $CO_2$ emissions and fossil emissions across countries. The results support the carbon EKC hypothesis, while monotonic increasing function exists in case of fossil fuel energy. The study emphasizes the need to ensure environmental sustainability agenda by adopting cleaner production technologies in WEF resources.

Amelioration of Cognitive Dysfunction in APP/PS1 Double Transgenic Mice by Long-Term Treatment of 4-O-Methylhonokiol

  • Jung, Yu-Yeon;Lee, Young-Jung;Choi, Dong-Young;Hong, Jin Tae
    • Biomolecules & Therapeutics
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    • 제22권3호
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    • pp.232-238
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    • 2014
  • Alzheimer's disease (AD) is the most common neurodegenerative disease without known ways to cure. A key neuropathologic manifestation of the disease is extracellular deposition of beta-amyloid peptide (Ab). Specific mechanisms underlying the development of the disease have not yet been fully understood. In this study, we investigated effects of 4-O-methylhonokiol on memory dysfunction in APP/PS1 double transgenic mice. 4-O-methylhonokiol (1 mg/kg for 3 month) significantly reduced deficit in learning and memory of the transgenic mice, as determined by the Morris water maze test and step-through passive avoidance test. Our biochemical analysis suggested that 4-O-methylhonokiol ameliorated $A{\beta}$ accumulation in the cortex and hippocampus via reduction in beta-site APP-cleaving enzyme 1 expression. In addition, 4-O-methylhonokiol attenuated lipid peroxidation and elevated glutathione peroxidase activity in the double transgenic mice brains. Thus, suppressive effects of 4-O-methylhonokiol on $A{\beta}$ generation and oxidative stress in the brains of transgenic mice may be responsible for the enhancement in cognitive function. These results suggest that the natural compound has potential to intervene memory deficit and progressive neurodegeneration in AD patients.

Comparison of physiological responses soybean [Glycine max (L.) Merill] of different irrigation Periods

  • Kim, Eun Hye;Chung, Ill Min
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.195-195
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    • 2017
  • The water in the crop cultivation shows difference according to the variety of crop, cultivations period and climatic condition. The growth and development, quantity and fruit enlargements are affected by soil water conditions. In previous study, leaf area and photosynthesis are decreased by lower soil moisture. Other research reported that excess moisture condition at vegetative and reproductive growth period in cultivation of soybean caused highest reduction in crop growth rate (CGR) and dry weights of plant parts. In particular, the damage was bigger during vegetative growth stage than reproductive growth period. Soybean (Glycine max (L.) Merill) is useful and popular crop throughout the world. It is very popular crop in Korea, China, Japan and other Asian countries. Soybeans used in various way including soybean sprouts, paste, soymilk, oil and tofu. Two soybean cultivars grown in four different irrigation conditions were determined for physiological responses. In this study, we examined leaf area (LA), leaf dry weight (LDW), specific leaf area (SLA), root dry weight (RDW) and shoot height (SH) in different water conditions. 50mL/9day irrigation periods showed the lowest contents in LA, LDW, RDW, SH. Water deficit caused increase of leaf Water saturation deficits (WSD), Cheongjakong 3 and Taekwangkong showed increase of leaf water saturation deficits (WSD) in drought conditions and leaf water potential and stomatal conductance were decreased. Photochemical efficiency was decreased in 50mL/1day irrigation condition while, there was decrease of growth and development in 50mL/9day with drought.

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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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Landsat ETM+ 영상을 활용한 경작지역내 가뭄민감도의 연구 (A Study of Drought Susceptibility on Cropland Using Landsat ETM+ Imagery)

  • 박은주;성정창;황철수
    • 대한원격탐사학회지
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    • 제19권2호
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    • pp.107-115
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    • 2003
  • 이 연구는 위성 영상을 이용하여 경작지에 나타나는 2001년 봄가뭄의 가뭄심도를 탐지하였다. 우리나라에 매년 피해를 주는 봄가뭄은 주로 기상학적 가뭄지수에 의해 모니터링되기 때문에 미시적 차원에서의 가뭄 현황 파악이 어렵다. 따라서, 각 경지에 대한 지표특성을 반영해주는 가뭄의 국지적 연구가 필요하다. 이 연구는 농작물 생육과 성장에 가장 큰 영향을 주는 토양수분을 지표로 2001년의 농업적 가뭄에 대해 분석하였다. 특히, 태슬 모자형(Tasseled cap)변환과 지형적 요인들을 이용하여 가뭄의 정도와 공간적 분포를 탐지하였다. 연구지역의 가뭄분석에서 Landsat 7 ETM/sub +/ 영상의 태슬 모자형 변환을 통해 추출된 수분 지수가 농경지의 가뭄 민감도를 잘 나타내었다. 수분지수는 다양한 토양 수분의 정도를 잘 표현해 주기 때문에, 수분 지수로 가뭄의 심도를 확인 할 수 있었다. 특히, -0.2 이하의 수분지수 값이 나타내는 화소(Pixel)들은 2001년 봄가뭄으로 심각한 용수부족피해를 겪고 있던 경작지로 나타났다. 그 화소들과 지형변수를 이용하여 가뭄심도를 구하는 모델을 구현하였다.