• Title/Summary/Keyword: Leaf temperature

Search Result 1,231, Processing Time 0.031 seconds

Daily Changes in Red-Pepper Leaf Surface Temperature with Air and Soil Surface Temperatures

  • Eom, Ki-Cheol;Lee, Byung-Kook;Kim, Young-Sook;Eom, Ho-Yong
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.47 no.5
    • /
    • pp.345-350
    • /
    • 2014
  • This study was conducted to investigate the changes in daily surface temperature of red pepper leaf compared to air and soil surface temperature. The maximum, minimum and average daily temperatures of red pepper leaf were 27.80, 11.40 and $19.01^{\circ}C$, respectively, which were lower by 0.10, 7.60 and $3.86^{\circ}C$ than air temperature, respectively, and lower by 15.00, 0.0 and $4.38^{\circ}C$ than soil surface temperature, respectively. Mean deviations of the difference between measured and estimated temperature by the E&E Model (Eom & Eom, 2013) for the air and surface temperature of red pepper leaf and soil were 0.64, 1.82 and $4.77^{\circ}C$, respectively. The relationships between measured and estimated scaled factor of the air and surface temperature of red pepper leaf and soil were very close to the 1:1 line. Difference between air and surface temperature of red pepper leaf showed a linear decreasing function with the surface temperature of red pepper leaf. Difference between soil surface temperature and air and surface temperature of red pepper leaf linearly increased with the soil surface temperature.

Estimation Model of the Change in Dairy Leaf Surface Temperature Using Scaling Technique

  • Eom, Ki-Cheol;Eom, Ho-Yong
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.46 no.5
    • /
    • pp.359-364
    • /
    • 2013
  • This study was conducted to develop a model to estimate crop leaf surface temperature. The results were as following; A definition for the daily time based on elapsed time from the midnight (00:00) as "E&E time" with the unit of Kmin. was suggested. The model to estimate the scaled temperature ($T^*e$) of crop leaf surface temperature by scale factor ($T^*$) according to the "E&E time : Kmin."(X) was developed as eq. (1) $T^*e=0.5{\cdot}sin(X+780)+0.5$ (2) $T^*=(Tx-Tn)/(Tm-Tn)$, Tx : Daily leaf temperature, Tm : Daily maximum leaf temperature, Tn : Daily minimum leaf temperature. Relative sensitivity of the measured temperature compared to the estimated temperature of red pepper, soybean and persimmon was 1.078, 1.033 and 0.973, respectively.

On the Diurnal Change of Leaf Temperature of Herbaceous Plants in Plant Community (군락상태에 있는 초본식물의 엽온의 일조변화)

  • 임양재
    • Journal of Plant Biology
    • /
    • v.17 no.3
    • /
    • pp.107-112
    • /
    • 1974
  • Leaf temperature is complicated with the microclimate and the dry matter production in a plant community. But a daily change of leaf temperature varying by the locality in plant body or plant community is not yet clear. To resolve such a question, following experiment was designed; Helianthus tuberosus L., Glycine max L., Zea mays L., Impomoea batatas Lam., and Cucurbita moschata var. toonas Makino were planted in the different sandy loam, $2m{\times}2m-quadrat$, which has a eastern, southern, western and northern edge. In each plot 17-25 plants were planted and the distances between individuals spaced uniformly. And leaf temperature were measured by MR3-C type thermistor from 14th May through 20th August. It is seems that the upper leaf is affected by solar radiation, the lower leaf by released heat from the earth and the middle leaf by the conditions of both zones. Measuring the temperature of a leaf that is on terminal, central, left and right margins and base part, temperature of control plant in a leaf was sloped during about two hours from noon. It is noticeable as a "noon sleeping" phenomenon.henomenon.

  • PDF

Using Leaf Temperature for Irrigation Scheduling in Greenhouse (온실작물의 관개계획의 수립을 위한 엽온의 활용)

  • 이남호;이훈선
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.43 no.6
    • /
    • pp.103-112
    • /
    • 2001
  • The development of infrared thermometry has led many researchers to use plant temperatures, and specifically the temperature of the crop canopy in the field, for estimating the water stress of a crop. The purpose of this study was to evaluate the role of leaf temperature in irrigation scheduling. An experiment was carried out in a greenhouse with chinese cabbage. Leaf temperature was measured with infrared thermometry and evapotranspiration of the crop was measured by lysimeters. Influence of the difference between leaf temperature and air temperature on crop evapotranspiration was evaluated under varying water stress condition. A further objective was to evaluate the effect of other climatic variables on the relationship between evapotranspiration and temperature difference between leaf and air. A statistical model for estimating evapotranspiration using the temperature difference, relative humidity. and radiation was developed and tested. Crop water stress index was calculated using vapour pressure deficit and the temperature difference. Relations between the crop water stress index and crop evapotranspiration was tested. The index was closely related with evapotranspiration.

  • PDF

Changes of Inorganic Nutrient Contents in Leaf of 'Niitaka' Pear and Inorganic Nutrient Contents of Leaf Influenced by Meteorological Elements (배 신고 품종의 잎 내 무기성분의 시기별 함량 변화와 잎 내 무기성분 함량에 미치는 기후요인)

  • Kim Ik-Youl;Ryu Jong-Ho;Kim Mi-Young
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.7 no.3
    • /
    • pp.192-200
    • /
    • 2005
  • This study was conducted to investigate inorganic nutrient contents in spur leaf and shoot leaf of 'Niitaka' pear during the growing season and leaf inorganic nutrient contents as influenced by meteorological elements. The contents of N, P, K, and Mg were decreased in spur leaf during their vegetative growth, while Ca and Mn increased. The contents of N, P, K, Mg, and Fe showed no differences between spur leaf and shoot leaf. However Ca, Mn, Zn, and Cu contents were higher in spur leaf than those in shoot leaf, but B content was lower in spur leaf than those in shoot leaf. The content of N in shoot leaf was positively correlated with mean temperature, whereas negatively correlated with maximum temperature. The content of P in spur leaf was negatively correlated with maximum temperature. The content of Ca in spur leaf was negatively correlated with mean temperature, whereas positively correlated with maximum and minimum temperature. The contents of Mg and B in shoot and spur leaf were positively correlated with mean temperature, whereas negatively correlated with maximum and minimum temperature. The contents of Ca and Mn showed significant differences between spur leaf and shoot leaf at mid-July to early August. These results suggest that sampling is important to distinguish between spur leaf and shoot leaf for diagnosis of nutrient conditions in pear trees.

Effect of Active Nutrient Uptake on Heading Under Low Temperature in Rice

  • Hwang, Woon-Ha;Kang, Jea Ran;Baek, Jung-Sun;An, Sung-Hyun;Jeong, Jae-Heok;Jeong, Han-Yong;Lee, Hyen-Seok;Yun, Jong-Tak;Lee, Gun-Hwi;Choi, Kyung-Jin
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.61 no.3
    • /
    • pp.163-170
    • /
    • 2016
  • Heading time is important element for yield and quality in crops. Among day length and temperature which influence on heading, temperature effect has not been investigated well. To investigate temperature effect on heading, heading date and plant growth characters were checked under the low and high temperature conditions in short day length. Analyzing heading date of six Korean varieties under the high and low temperature condition, heading date of varieties were delayed under low temperature. In the low temperature condition, dry weight and area of leaf were reduced. Varieties showing more delay of heading under low temperature also showed more reduction in leaf area. After selecting three varieties showing significant difference in leaf growth and heading date under different temperature conditions, nutrient contents of plant were analyzed. Nitrogen content was reduced in leaf and shoot under the low temperature condition. OsNRT2.3, nitrate transporter, was significantly down regulated in varieties showing more heading delay. Available phosphate content was decreased in leaf, but increased in shoot due to reduction of phosphate mobility. OsPT1, phosphate transporter regulating phosphate uptake, was more down regulated in varieties showing more heading delay. OsPT6, phosphate transporter regulating phosphate transport in plant, was also significantly down regulated in those varieties. With these data, we expected that active nitrogen and available phosphate uptake and transport in plant would increase leaf growth then might reduce heading delay under the low temperature condition.

Comparing a Perspective on the Leaf Burst Timing and Leaf Growth Performance of Major Plants observed in Urban Forests (도시녹지 내 주요 식물상의 개엽시기 및 잎의 성장 특성 비교)

  • Jang, Gab-Sue
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.15 no.2
    • /
    • pp.127-136
    • /
    • 2012
  • Global climate change and urban heat island have been the main factors which changed leaf burst timing and leaf growth performance in urban forests. Therefore, the ecosystem in urban forests were modified and the types and composition of wildlives, living in the urban forests, were desperately changed due to the urban heat island. This study was done to identify phenological phenomena appeared in urban forests due to the urban climate change by comparing the morphological changes of leaves due to the change of temperature in Spring. The study focused on nine urban forests distributed in Daegu city, where weekly temperature and the morphological changes of the plants were mainly observed. Urban forests had different temperature depending on where each was located in the urban area. The difference of temperature in forests in and outside the urban area was verified by SPSS (Statistical Package for the Social Sciences), which divided the urban forests into about three groups; the one located outside the city, another group located in the middle of the city, and the other located close to the outside forests. The forests located in the middle of the city were showing the earlier leaf burst timing and leaf growth performance, while forests, distributed outside the city, were showing relatively late leaf burst timing and leaf performance.

Physiological Response of Panax Ginseng to Tcmpcrature II. Leaf physiology, soil temperature, air temperature, growth of pathogene (인삼의 온도에 대한 생리반응 II. 엽의 생리, 지온, 기온, 병환의 생육)

  • Park, Hoon
    • Journal of Ginseng Research
    • /
    • v.4 no.1
    • /
    • pp.104-120
    • /
    • 1980
  • The effects of temperature on transpiration, chlorophyll content, frequency and aperture of stomata, and leaf temperature of Panax ginseng were reviewed. Temperature changes of soil and air under spade roof were also reviewed. Growth responses of responses of ginseng plant at various temperature were assessed in relation to suseptibillity of ginseng plants. Reasonable management of ginseng fields was suggested based on the response of ginseng to various temperatures. Stomata frequency may be increased under high temperature during leaf$.$growing stage. Stomata aperture increased by high temperature but the increase of both frequency and aperture appears not enough for transpiration to overcome high temperature encountered during summer in most fields. Serial high temperature disorder, i.e high leaf temperature, chlorophyll loss, inhibition of photosynthesis, increased respiration and wilting might be alleviated by high humidity and abundant water supply to leaf. High air temperature which limits light transmission rate inside the shade roof, induces high soil temperature(optimum soil temperature 16∼18$^{\circ}C$) and both(especially the latter) are the principal factors to increase alternaria blight, anthracnose, early leaf fall, root rot and high missing rate of plant resulting in poor yield. High temperature disorder was lessen by abundant soil water(optimum 17∼21%) and could be decreased by lowering the content of availability of phosphorus and nitrogen in soil consequently resulting in less activity of microorganisms. Repeated plowing of fields during preparation seems to be effective for sterilization of pathogenic microoganisms by high soil temperature only on surface of soils. Low temperature damage appeared at thowing of soils and emergence stage of ginseng but reports were limited. Most limiting factor of yield appeared as physiological disorder and high pathogen activity due to high temperature during summer(about three months).

  • PDF

Variation in leaf functional traits of the Korean maple (Acer pseudosieboldianum) along an elevational gradient in a montane forest in Southern Korea

  • Nam, Ki Jung;Lee, Eun Ju
    • Journal of Ecology and Environment
    • /
    • v.42 no.4
    • /
    • pp.278-284
    • /
    • 2018
  • Plant functional traits have been shown to be useful to understand how and why ecosystems and their components vary across environmental heterogeneity or gradients. This study investigated how plant functional (leaf) traits vary according to an elevation-associated environmental gradient. Environmental gradients (mean annual temperature and precipitation) were quantified, and leaf traits (leaf area, specific leaf area, leaf nitrogen, leaf phosphorus, leaf carbon, and leaf C/N ratio) of the understory woody plant species Acer pseudosieboldianum were examined across an elevational gradient ranging from 600 to 1200 m in a Baegunsan Mountain in Gwangyang-si, Jeollanam-do, South Korea. The results showed that mean annual temperature and precipitation decreased and increased along with elevation, respectively. Leaf area of the plant species decreased slightly with increasing elevation, while specific leaf area did not differ significantly. Leaf nutrients (nitrogen, phosphorus, and carbon concentrations) were higher at high elevations, but leaf C/N ratio decreased with elevation.

The Decomposition of Leaf Litters of Some Tree Species in Temperate Deciduous Forest in Korea I. Losses in Dry Weight of Leaf Litter

  • Yang, Keum-Chul;Shim, Jae-Kuk
    • The Korean Journal of Ecology
    • /
    • v.26 no.4
    • /
    • pp.203-208
    • /
    • 2003
  • Losses in the dry weight of leaf litter from six tree species were studied during 16 months on the forest floor in temperate deciduous forest of Mt. Cheonma in the vicinity of Seoul in Korea by using litter bag method. The decomposition rate of each leaf litter varies with each species. After 16 months elapsed, the leaf litter of Acer pseudo-sieboidianum showed the highest decomposition constant (0.82) as Olson´s decomposition constant, while that of Pinus densiflora showed the lowest decomposition constant (0.33). The decomposition constant of Quercus mongolica, Q. serrata, Betula ermani and Carpinus laxiflora showed 0.43, 0.37, 0.66 and 0.75, respectively. The decomposition constant of leaf litter was considered with temperature and precipitation which accumulated daily during each term of litter bag collection. The decomposition constant of leaf litter showed closely positive correlation with daily accumulative temperature and precipitation. The relationships between decomposition constant and the daily accumulative temperature and precipitation at each period of litter bag collection were analyzed through multi-regression analysis. The correlation coefficients as a result of multi-regression analysis in Q. mongolica, Q. serrata, P densiflora, B. ermani, C. laxiflorais and A. pseudo-sieboldianum were 0.83, 0.81, 0.69, 0.77, 0.77 and 0.62, respectively. The precipitation showed higher effect, about 10 times, on the leaf litter decomposition than the daily accumulative temperature.