The purpose of the present study is to estimate air temperature in areas where there is no meteorological observation site, using satellite thermal IR data. Surface temperature from GMS IR data derived by eq. (1) was compared with AMeDAS (meteorological observation site) air temperature. The results are summarized as follows:
1) The maximum correlation coefficients between AMeDAS air temperature and surface temperature from GMS IR data is 0.90, the minimum is 0.30 and the mean is 0.60±0.15.
2) The correlation coefficients are affected by the precipitable water and decrease with increasing precipitable Water as shown in Fig. 2.
3) The correlation coefficients for each GMS observed time are better at night and in the morning than during the day (Table 2).
4) Also, the small values of the regression coefficients appear during the day and the large values at night and in the morning (Table 2).
5) The standard deviations which indicated scattering around the regression line are large at 12:00 and 15:00, but small at 06:00 and 09:00 (Table 2).
The reason that correlation coefficients, regression coefficients and standard deviations between AMeDAS air temperature and surface temperature from GMS IR data are less during the day than at night and in the morning, is caused by ground conditions because the effects of solar radiation on surface temperature depend on ground surface conditions: plant cover, incline of slope etc.
The hourly mean deviation from the regression line for surface temperature was calculated to investigate the characteristic of ground surface conditions for each AMeDAS observation site. AMeDAS observation sites were classified into four types according to the patterns of the hourly mean deviation as shown in Fig. 5. Most of type I were distributed in the plain regions: Ishikari, Konsen and Tokachi. Type II appears in the basin regions and type III on the coast of the Pacific Ocean and the Sea of Okhotsuk. The remaining areas are type IV.
The standard deviations for all data, over 2.0°C and under 1.3°C were plotted on a map. Most sites with large standard deviations correspond to those of type III, while those with the small standard deviations correspond to sites of type I.
The hourly changes of standard deviations are shown in Fig. 7. The large standard deviations appears on the coast of the Pacific Ocean and the Sea of Okhotsuk from 09:00 to 18:00. The sites of the small standard deviations appear more in the morning at 06:00 than during the day and at night.

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The relationship between CO₂ concentration in the rhizosphere and the growth of cucumber plant was studied. Growth rates of cucumber plant growing in the sand culture were compared for CO₂ concentration varying from 0 to 5% in the rhizosphere. The effects of CO₂ and O₂ in the rhizosphere on photosynthetic rate were then investigated.
The results obtained were as follows.
(1) The growth suppression of cucumber plant occurred at 0.5-2% CO₂ in the rhizosphere. Total dry weight and leaf area decreased up to 80-90% by the increase of CO₂ concentration (2-5%) in the rhizosphere.
(2) The growth suppression by CO₂ was found five days after the beginning of treatments.
(3) Water content of the top decreased with increase in CO₂ concentration in the rhizosphere.
(4) Photosynthetic rate decreased two hours after the beginning of treatments even at 3-5% CO₂. After four hours, photosynthetic rate at 10% CO₂ declined up to 85% of that before the treatment, while it retained 95% when treated with 10% O₂.
As described above, it is proved that the growth of cucumber plant is suppressed with increase in CO₂ concentration in the rhizosphere before the suppression by decreasing O₂ concentration occurs.

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Continual measurement of energy fluxes in a fan-ventilated plastichouse had been carried out during the growing season of melon crops. The equations to estimate the ventilation rate were derived from the experimental results.
The experimental plastichouse had a floor area of 200m². A fan with a capacity of 320m³ min^-1 at the gauge pressure of 1.5mmAq was used to ventilate the plastichouse. Two different mulch conditions were examined; one without mulch and the other with 80% of the floor area covered. The experiment was conducted from April to June, 1977.
Inside net radiation and soil heat flux were measured with a net radiometer and heat flux plates, respectively. Both sensible and latent heat flux due to ventilation were calculated from the ventilation rate and the dry and the wet bulb temperatures measured inside and outside the plastichouse. Heat transmission through glazing was estimated from the inside-outside temperature difference and the heat transmission coefficient.
1. The ratio of latent heat flux to inside net radiation increased with the increase in LAI. The mean value of the ratio for LAI more than 1 was 55.1% when the floor was not covered with mulch, while 52.6% when 80% covered.
2. Sensible heat flux due to ventilation gradually decreased with the increase in LAI. The mean ratio to net radiation for LAI more than 1 was 32% when not covered, while 36% when 80% covered To maintain the same inside air temperature, therefore, it is estimated that more ventilation rate is required when the floor is covered than the case when not covered.
3. When LAI was small, sensible heat flux due to ventilation exceeded latent heat flux, while it was reverse when LAI was large. This change occurred at LAI equale to 0.4 when the floor was not covered, but at LAI of 0.7 when 80% covered.
4. Heat transmission through glazing was also affected by the floor cover. Its ratio to the inside net radiation was averagely 7% when not covered, while 8.9% when 80% covered.
5. Soil heat flux was less dependent on the floor cover, but more on LAI. Namely, the flux decreased as LAI increased. The average ratio during the growing season was 6%.
6. Bowen ratio in the ventilation heat fluxes at LAI of 0.08 was 1.44 without floor cover and 2.77 with mulch. These ratios decreased with the increase in LAI.
7. The following equations to estimate the ventilation rate was derived experimentally from the energy balance measurement.
In case without mulch,
q=1/c_pρ(0.437aS_i/t_i-t_o-wk)
In case 80% of the floor covered,
q=1/c_pρ(0.481aS_i/t_i-t_o-wk)
where, q; ventilation rate, c_p; specific heat of air, ρ; air density, a; ratio of sunlit area to total floor area, S_i; inside net radiation, t_i; inside air temperature, t_o; outside air temperature, w; floor to glazing area ratio, k; heat transmission coefficient of glazing.

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The growth response of kidney bean to artificial rainfall (mist) treatment was investigated. Plants were exposed to mist (5mm/h, Diameter of water drop: 0.24mm) in a growth chamber (20°C, 6k lux) for several days, and then kept at 20°C in the phytotron (natural light). Shoot length, root length, fresh weight and dry weight were measured and degree of leaf injury was examined 18 days after the beginning of the mist treatment.
1) Exposure to mist caused injury of the primary, the 1st and 2nd foliage leaves of kidney bean. Forty percent of the primary leaves were injured by 1-day mist treatment and all of them by 4-day treatment. The sign of injury in primary leaves was always crinkle symptom. Exposure to mist for 1-2 days caused only slight injury in the 1st and 2nd foliage leaves, but the injury was increased by a longer exposure. Almost all the 1st leaves were injured by exposure to mist for 4 days and almost all the 2nd leaves were injured by 5-day mist treatment. Various symptoms, such as edge break leaf, necrotic spot leaf, cordate leaf and rugose leaf, appeared as a result of the necrosis of leaf tissue.
2) In general, the growth was promoted after mist treatment for 1 day, but growth rate became reduced gradually with increasing duration of mist exposure beyond 1 day. Shoot and root elongation was decreased by exposure to mist for 5 days or more. Fresh weight of the shoot decreased after a 3-day or longer exposure to mist, and that of the root decreased after a 2-day or longer exposure. Dry weight of the shoot decreased after exposure to mist for 4 days or more and that of the roots decreased after exposure for 2 days or more.
3) Exposure of only the shoot to mist and the use of deionized water had a similar effect on injury of leaves and growth inhibition.
4) These results suggested that exposure of shoot to rainfall greatly influences the subsequent growth responses, the exposure for 3 days or more having a marked effect.

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Forced-convection coefficients of water-vapor transfer through the boundary-layer on a rectangular flat plate surface (leaf model) inclined to laminar air flow were evaluated in relation to the inclination angle and the dimension of the surface. The average transfer coefficients on a leaf model were obtained from the measurements of water evaporation from the wet surface of plates with aspect ratios of 0.05 to 50 and several different dimensions, and various inclination angles to the flow. Forced-convection transfer coefficients were estimated after taking free-convection transfer coefficients from measured boundary-layer transfer coefficients.
At Reynolds numbers less than each critical value, the forced-convection coefficients for both surfaces facing into and away from the air flow were apparently proportional to the square root of wind speed, except for the surface facing away from the flow attacking on the plate with aspect ratios of around 2.5 at angles of 5° to 20°; for the latter surfaces, the critical Reynolds numbers were especially small.
For the surface facing away from the flow, with an aspect ratio of about 1 and 2.5, the forced-convection coefficients increased with increasing angle for angles less than 30° until they decreased with increasing angle. For the surface with aspect ratios smaller than unity, the coefficients decreased with increasing angle. While, for surfaces with aspect ratios larger than about 4, the transfer coefficients increased with increasing angle. On the other hand, for the surface facing into the flow, all the forced-convection coefficients increased with increasing angle.
In the case when the forced-convection coefficients were proportional to the square root of the wind speed and increased with increasing angle, an experimental equation about the transfer coefficients for flat leaf models inclined to the air flow was formulated as follows,
α_i=D_{f, φ}/D_{f, φ=0}=1+a(sinφ)^p,
where α_i is the increment ratio of the forced-convection coefficient (D_{f, φ}) for the surface with the inclination angle (φ) to that (D_{j, φ=0}) set in parallel with the air flow (φ=0), and a and pβ are empirical constants which were determined by the least squares method.
For the surfaces facing into, and in parallel with the air flow,
a=0.26(l/s)^0.57,
and p increases nearly to 0.8 for aspect ratios from 0.05 to 10, while p is about 0.8 for greater aspect ratios than 10, where l is the length of the rectangular surface in the direction of the flow and s is the transverse width. The experimental equation mentioned above is applied to the surfaces under Reynolds numbers below 1×10⁵.
For the surfaces facing away from the flow,
a=0.12(l/s)^0.54, for l/s≥2.5,
and p=0.32 (l/s)^0.25 for l/s≥4.
These equations are applied to the surfaces under Reynolds numbers less than a value given to each combination of the surface-aspect-ratio and inclination angle: for example, they are about 7×10³ and 1×10⁵, respectively, for the surface of 2.5 in aspect ratio (the length is 5cm and the width is 2cm) and -30° in inclination angle, and that of 40 in aspect ratio (40cm long and 1cm wide) and -20° in inclination angle.

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