• Journal of Forest and Environmental Science
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• v.23 no.1
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• pp.29-33
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• 2007

This study was purposed to elucidate the best optimum sites by ecophysiological response measurements of Kalopanax pictus samplings of plantation. The diurnal changes of the stomatal transpiration, water use efficiency, water potential, and intercellullar $CO_2$ concentration of leaves were measured by the portable IR $CO_2$ analyzer. The results obtained are summarized as follows. 1) The daily stomatal transpiration rate was highest at 10:00 a.m. After 16:00, the stomatal transpiration rate rapidly decreased. 2) The daily water use efficiency was maximum at 8:00 a.m., and then rapidly decreased until midday with decreasing water potential. 3) The daily $C_i/C_a$ ratio rapidly decreased until 9:00 a.m., and then showed a stable value until 16:00, and then rapidly increased. The daily intercellullar $CO_2$ concentration ($C_i/C_a$ ratio) showed the same tendency as water potential changes. Consequently, stomatal transpiration and water use efficiency was increased with high water potential of leaves at am, and then remarkably decreased with low water potential at pm.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.218-231
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• 2005

This paper reviews the engineering approach needed to support humans during their long-term missions in space. This approach includes closed plant production systems under microgravity or low pressure, mass recycling, air revitalization, water purification, waste management, elimination of trace contaminants, lighting, and nutrient delivery systems in controlled ecological life support system (CELSS). Requirements of crops f3r space use are high production, edibility, digestibility, many culinary uses, capability of automation, short stems, and high transpiration. Low pressure on Mars is considered to be a major obstacle for the design of greenhouses fer crop production. However interest in Mars inflatable greenhouse applicable to planetary surface has increased. Structure, internal pressure, material, method of lighting, and shielding are principal design parameters for the inflatable greenhouse. The inflatable greenhouse operating at low pressure can reduce the structural mass and atmosphere leakage rate. Plants growing at reduced pressure show an increasing transpiration rates and a high water loss. Vapor pressure increases as moisture is added to the air through transpiration or evaporation from leaks in the hydroponic system. Fluctuations in vapor pressure will significantly influence total pressure in a closed system. Thus hydroponic systems should be as tight as possible to reduce the quantity of water that evaporates from leaks. And the environmental control system to maintain high relative humidity at low pressure should be developed. The essence of technologies associated with CELSS can support human lift even at extremely harsh conditions such as in deserts, polar regions, and under the ocean on Earth as well as in space.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.152-165
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• 1993

This is the basic study in order to know the amount of transpirational water loss in a Larix leptorepis stand by a heat pulse method. Especially this study has been measured and discussed the diurnal and seasonal trends of heat pulse velocity by changes of radiation, temperature and humidity, differences of heat pulse velocity by direction and depth in stem, differences of heat pulse velocity by dominant, codominant and suppressed trees, diurnal change of heat pulse velocity by change of leaf water potential, sap flow path way in sapwood by dye penetration and amount of daily and annual transpiration in a tree and stand. The results obtained as follows : 1. Relation between heat pulse velocity(V) and sap flow rate(SFR) was established as a equation of SFR=1.37V($r=0.96^{**}$). 2. The sap flow rate presented in the order of dominant, codominant and suppressed tree, respectively. The daily heat pulse velocity was changed by radiation, temperature and vapor pressure deficit. 3. The heat pulse velocity in individual trees did not differ in early morning and in late night, but had some differed from 12 to 16 hours when radiation was relatively high. 4. The heat pulse velocity and leaf water potential showed similar diurnal variation. 5. The seasonal variation of heat pulse velocity was highest in August, but lowest in October and similar value of heat pulse velocity in the other months. 6. The heat pulse velocity in stem by direction was highest in eastern, but lowest in southern and similar velocity in western and northern. 7. The difference of heat pulse velocity in according to depths was highest in 2.0cm depth, medium in 1.0cm depth, and lowest in 3.0cm depth from surface of stem. 8. The sap flow path way in stem showed spiral ascent turning right pattern in five sample trees, especially showed little spiral ascent turning right in lower part than 3m hight above ground, but very speedy in higher than 3m hight. 9. The amount of sap flow(SF) was presented as a equation of SF=1.37AV and especially SF in dominant tree was larger than in codominant or suppressed tree. 10. The amount of daily transpiration was 30.8ton/ha/day and its composition ratio was 83% at day and 17% at night. 11. The amount of stand transpiration per month was largest in August(1,194ton/ha/month), lowest in May (386ton/ha/month). The amount of stand transpiration per year was 3,983ton/ha/year.

• Journal of Bio-Environment Control
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• v.25 no.1
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• pp.57-62
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• 2016

This study was conducted to find out the influence of red LED (Light Emitting Diode) lighting on the photosynthesis, vegetative growth and fruit quality of 'Fuji'/M.26 adult apple tree during night after sunset. The photosynthetic rate, stomatal conductance and transpiration rate at daytime of red LED treatments was not different to those of the control. However, the stomatal conductance and transpiration rate at the nighttime of red LED treatments were lower than those of the control, and the red LED lighting during night after sunset was not induce to photosynthesize at nighttime. In the leaf characteristics, the red LED lighting seemed to increase leaf area and C/N ratio, but decrease SPAD value. The bourse shoot length of the red LED treatments was shorter than that of the control. In the fruit quality, the red LED lighting seemed to increase ethylene production, respiration rate, soluble solid content and fruit red color, and especially the fruit red color tend to increase as the red LED lighting time was longer. In conclusion, the red LED lighting during night after sunset of 'Fuji'/M.26 apple tree promoted the fruit maturation.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.11a
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• pp.14-19
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• 1997

식물의 광반응은 광질과 광강도에 따라 상이하며, 광은 열을 동반하게 되므로 광만을 분리하여 생각할 수 없다. 즉, 광은 식물체의 체온과 엽온을 높이고, 잎의 수증기 장력을 증가시켜 증산을 촉진하므로 기화열을 발생하는 원동력이 되기도 한다. 따라서 광은 잎속의 수분이나 기공개도 등에 영향을 주기 때문에 광합성속도에 간접적인 영향을 미치기도 한다. (중략)

• Korean Journal of Medicinal Crop Science
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• v.15 no.4
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• pp.276-284
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• 2007

To investigate the influence of shading materials with growing stages in Panax Ginseng C. A. Meyer, the diurnal change of photosynthesis, stomatal conductance, transpiration and its any correlation were measured. The net photosynthetic rate and stomatal conductance of ginseng were higher in the morning than in the broad day. The net photosynthetic rate was increased as the PAR (Photosynthetically Action Radiation) was increased and it was reached the maximum at the $200\;{\mu}mol/m^2/s$ of PAR in overall leaves. Transpiration rate was increased in the afternoon compared to in the morning. The transpiration rate was higher in rain shelter shading plate than in polyethylene net. A linear equation was obtained between net photosynthetic rate and stomatal conductance in the morning. SPAD was higher in rain shelter shading plate than in polyethylene net through all growth stages. It may result from the decrease of growth progress. From investigating photosynthetic characteristics, we concluded that shading plate of rain shelter was more an efficient material to ginseng growth.

• Food Science and Preservation
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• v.1 no.1
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• pp.37-43
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• 1994

A microcomputer system consisting of 16-bit microcomputer, PCL-711S interface board, censors, and converters have been set up in order to automatically measure temperature, humidity and weight loss which are major variables of storage of apple. This system was operated by PC-LabDAS software. It has been possible to measure continuously the weight loss of Fuji apple stored in CA with the weight converter made by a miniature load cell and a strain amplifier. The temperature was checked by a k-type thermocouple and Pt 100 $\Omega$ RTD, and humidity by PQ653JAl humidity sensor. It has been possible to set up a linear equation which showers high correlationship between the estimate of temperature, weight humidity and the output of the converter in that r2 is more than 0.99. Transpiration rate, a significant factor of quality deterioration for CA storage of apple, can be estimated with these values.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.510-516
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• 2016

This study was conducted to investigate the physiological responses of newly-germinated seedlings of Fraxinus rhynchophylla Hance, Zelkova serrata (Thunb.) Makino, Betula costata Trautv. and Quercus variabilis Blume to open-field experimental warming. The seedlings in the warmed plots were warmed with $2.7^{\circ}C$ higher air temperature than those in the control plots using infrared heaters since April, 2015. Physiological responses (stomatal conductance, transpiration rate, chlorophyll content and net photosynthetic rate) to experimental warming varied with the species and the time of the measurement. Stomatal conductance ($mmol{\cdot}m^{-2}{\cdot}s^{-1}$) tended to decrease for F. rhynchophylla (Control: $158.97{\pm}42.76$; Warmed: $42.07{\pm}8.24$), Z. serrata (Control: $170.53{\pm}27.22$; Warmed: $101.17{\pm}42.27$) and B. costata (Control: $249.93{\pm}47.39$; Warmed: $150.73{\pm}26.52$). Transpiration rate ($mmol{\cdot}m^{-2}{\cdot}s^{-1}$) also decreased for F. rhynchophylla (Control: $4.08{\pm}0.62$; Warmed: $1.74{\pm}0.39$), Z. serrata (Control: $4.32{\pm}0.44$; Warmed: $3.24{\pm}1.14$) and B. costata (Control: $6.21{\pm}0.38$; Warmed: $4.66{\pm}0.28$). However, warming exhibited only minimal effects on stomatal conductance and transpiration rate of Q. variabilis seedlings. Chlorophyll content increased by the warming treatment while the effect of warming was not significant on net photosynthetic rate, since the warming treatment had a weak influence for changing net photosynthetic rate.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.574-579
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• 2010

Waste nutrient solution (WNS) that was the drained nutrient solution of Horticultural Research Institute of Japan for culture tomato in perlite hydroponics showed $1.9-2.4dS{\cdot}m^{-1}$ of EC and 5.7-7.1 pH from April to July. Although ${NH_4}^+-N$ concentration of WNS decreased remarkably, the other nutrients did not change significantly, as compared with supplied solution. There were no significant differences in plant height, stem diameter, and the other growth characteristics of tomato plants grown by 2 fertigation nutrient solutions; BHF (Bountiful Harvest Fertilizer, 10% of N, 13% of $PO_4$, 13% of K, 0.05% of B, 0.05% of Zn, and 0.0023% of Cu that made in Korea) and Megasol (11% of N, 8% of $PO_4$, 34% of K, 0.032% of Mn, 0.002% of B, 0.048% of Fe, 0.0122% of Zn, and 0.0023% of Cu that made in Belgium.); however, the chlorophyll content of tomato leaf was highest in WNS. The fresh and dry weight of tomato plants were higher in 3 fertigation treatments than irrigation of tap water, while there were no significant differences in fresh and dry weight among the 3 fertigation treatments. The mineral content of tomato leaf also did not show any differences among the 3 fertigation treatments and any regular tendency in all minerals. Total yield, fruit weight and fruit numbers of tomato were higher in WNS, followed by Megasol, BHF and control, although there were not any difference among the 3 fertigation nutrient solution treatments. BER(blossom-end rot)of tomato fruits decreased in fertigation treatments, especially, fruits grown in WNS and BHF showed lower BER. However, the transpiration rate of leaf was higher in control, followed by BHF, WNS and Megasol, The fruit size and soluble solids content was higher in 3 fertigation nutrient treatments than control. These results suggest that WNS can be used for fertigation solution in tomato because yield and quality of tomato fruit grown in WNS fertigation treatment were similar to those in 2 fertigation nutrient solutions treatments(BHF, Megasol).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.111-118
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• 2010

Stress due to excess water is one of the most limiting factor for soybeans to high yield under wet climates. This study aimed to identify the photosynthetic responses of soybeans to waterlogged growing condition with 5 soybean varieties by waterlogging for 10 days at V5 and R2 stage, respectively. Chlorophyll fluorescence decreased more rapidly at R2 stage waterlogging than at V5 stage waterlogging in all soybean tested varieties. The degree of recovery was much more in Pungsannamulkong and Muhankong( 95～97% of control) than in Jangyeobkong and Myungjunamulkong at 5 days after waterlogging. Photosynthetic rate, transpiration and stomatal conductance were also increased more rapidly in Pungsannamulkong and Muhankong than in Jangyeobkong and Myungjunamulkong after waterlogging irrespective of waterlogging stages. As the result of multiple regression analysis in order to identify the effects of stomatal conductance and transpiration to the photosynthetic rate, the R2 value of stomatal conductance in control and waterlogging treatment was 0.7293 and 0.7582, respectively. If the transpiration, another dependent variable, was added to the regression formula, there was not so big difference in the variation of photosynthetic rate. This result means that if just one factor of them(the stomatal conductance and transpiration) be measured in the case of waterlogged condition, the changes of photosynthetic rate can be estimated.