The concentration of carbon dioxide of air in glasshouse and plastic house was studied from the micro-meteorological point of view.
The 60cc air at any place in the glasshouse is collected into the glass pipe and the air is analysed by the heat conductivity gas analyser improved by one of the authors (the original analyser was made by Godart Co., Holland.).
Figs. 1 and 2 show the distribution of the carbon dioxide concentration in melon stand in the glasshouse in June 1963 (the plant height is about 2m. high). The concentration in plant stand on bed shows lower degrees than the walk, which shows the distinguished distribution. Moreover the carbon dioxide in the plant stand shows remarkably lower concentration, which is less than a half value of the normal air. At night the concentration in the plant stand and the walk is reverse to the daytime distribution. And these distributions show that the soil is working as a main source of corbon dioxide.
As a case of low plant stand, Fig. 3 is drawn to show the diurnal change of vertical distribution of carbon dioxide concetration of lettuse stand in a plastic house in February 1964. As it is observed that the air circultion in the house occur along the ridge of roof and the plant was short, the concentration indicates about 240 p.p.m. at midday, though it does not show the distinguished distribution like in the melon house.
The glasshouse is closed tightly for keeping away from cold air during winter and furthermore the gravel culture glasshouse makes poor carbon dioxide production from the soil so that in gravel culture glasshouse the carbon dioxide content in air may decrease in bright day in winter. Fig. 4 shows the concentration in a glasshouse which is growing tomato by gravel culture in December 1963 (The plant height is about 2 m.). As mentioned above, the concentration is extremely low value and maintains only 70 p.p.m. at midday. And it means that under these conditions low rates of net assimilation occur.
As the results, one can conclude that the deficit in carbon dioxide under the closed system cultures retards the plant growth The growth analysis of plant have been studied mainly from the point of solar radiation and temperature, but more attention should be paid to carbon dioxide environment for plant growth.

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After Colburn Analogy between heat and mass transfer, the heat transfer coefficient can be determined by the mass transfer coefficient for forced or free convection.
The average vapor transfer coefficients (D_f) over a flat elliptic plate of naphthalene in the forced flow parallel to the minor axis are given by the following equations:
for the laminar boundary layer,
D_f=0.737·Re_2a^1/2·Sc^1/3d_N/2a
and for the turbulent,
D_f=0.0380·Re_2a^4/5·Sc^1/3d_N/2a
where Re_2a=Reynolds number, S_c=Schmidt number, d_N=melecular diffusion coefficient of naphthalene vapor into air, and 2a=length of minor axis.
For the free convection in the laminar range, the average coefficients on the upper surface of a horizontal elliptic plate are given as follows: for a warm plate,
Dn₁=0.45(Gr·Sc)^1/4d_N/1
and for a cold plate,
Dn₂=0.27(Gr·Sc)^1/4d_N/1
where Gr and 1 are the Grashof number and the mean length of major and minor axes.
For obtaining the heat transfer coefficient (h_f or h_n) from the corresponding mass transfer one, it is necessary to use conversion factors.
The conversion take the following forms:
for the forced convection,
h_f/D_f=(ρ_a·c_p)^1/3(k_a/d_N)^2/3
and for the free convection,
h_n/D_n=h_n1/D_n1=h_n2/D_n2=(ρ_a·c_p)^1/4(k_a/D_N)^3/4,
where ρ_a=density, c_p=specific heat, k_a=thermal conductivity of air.
These factors should be calculated when the reference temperatures are known.
On a small elliptic plate like a citrus leaf, it is obliged to recognize the edge effect increasing the heat and mass transfer in comparison with their theoretical values. This effect may be expressed by a corrective factor (α_f), that is the ratio of the observed to the theoreticl value of the average transfer coefficient.
In this experiment, the transfer rates of naphthalene vapor into the air from a flate lliptic plate, whose major and minor axes are and cm respectively, were mesaured in the range of wind velocity from 5 to 500cm/sec.
As the result, the observed values of the average vapor transfer coefficients are proportional to one-half power of wind velocity in the laminar flow and to the four-fifths power in the turbulent, as shown in Figs. 1 and 2.
Then, the heat transfer coefficients are calculated from these values using the conversion factor, and compared with the values on a citrus leaf reported in previous in vestigation of “Leaf Temperature” (1962 and '63). The values calculated from the naphthalene vapor transfer are in good agreement with the values for the citrus leaf.
Moreover, it is found the corrective factors (α_f)_N for the naphthalene vapor are almostly constant, independent of wind velocity. The mean values of (α_f)_N are 1.29 in the laminar flow and 1.36 in the turbulent.
These values are nearly equal to the previously given values of α_f for the heat transfer coefficients over a citrus leaf.
From these results, it may be proved that the corrective factor (α_f) is mainly due to theedge effect.

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The build-up mechanism of CO₂ concentration profiles within crop canopies is theoretically dealt with taking into account the absorption and/or liberation of CO₂ due to photosynthetic and/or respiratory activity of plant communities. The CO₂ budget equation is given by
d/dz(KdC/dz)=(εI-r)F,
where C, K, I, F, ε and r denote the CO₂ concentration, the eddy diffusivity, the visible light intensity, the leaf area density, the photosynthetic efficiency, and the respiration rate, respectively.
Assuming that both K and I are expressed by exponential functions and that F is independent of the height, C is given also in terms of the exponential function at the upper part of a canopy. The profile in the nighttime is given in terms of plant and soil respirations.
The compensation height of photosynthesis, where εI=r, is particularly dealt with from the budget equation, and the special convex feature of C-profile at that height is pointed out. A possible method of estimating micrometeorologically the quantities of ε and r of plant community is presented, and preliminary results of the application to a corn crop canopy of that method are given.

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Komagaike water warming reservoir is situated on the foot of Mt. Komagatake, Nagano Prefecture. The altitude of the site is about 850 meters and it takes in irrigation water from Ohotagiri River which drainages extremely cold water flowing from snow field of the mountain.
The observations were made in May and July, 1961. The observations had been continued to 1963, but in this report the results of heat economy observations in 1961 are reported. The observational stations around and in the reservoir are shown in Fig. 1, which include not only vartical distributions of microclimatic elements in the surface layer of air but also vartical distributions of water temperature in the reservoir. The analyses were made by two methods and the results of them were compared. The first is the calculation of surface heat economy by aerodynamical approach and the second is the calculation of heat storage in the reservoir using the values of vertical water temperatures in it. The observations were carried out every two hours, and the results of the calculations are summerized in Table 1. The difference between values of surface heat fluxes calculated by the two methods is about 6% for daily mean value. It will be concluded that the both methods will be reliable when the basic observations are made accurately.
The reservoir under consideration is rather small size but it has an unusual characteristic. The inlet of the reservois is situated at valley side of it and the outlet is situated at mountain side. Because of thi sconstructions, the reservoir has no remarkably horizontal dead water areas in mid-day when wind is blowing from the valley to upward. But the reservoir has rather great depth, and vertical dead water exists always. Density current is formed due to the cold water inflowing from the inlet into the reservoir and it is discharged quickly from the outlet. The trace of water flow was made by the eye observation using green dye. These results are shown in Figs. 2 and 4. Thermal efficiency of the reservoir is much low, because of existence of vertical dead water and application of the calculation equation (Δθ_cal) which is considered to be valid only for vertically isothermal water body. It had been assumed to be about 40%.
Diurnal amplitude of inflow and outflow water temperatures heve been reported by several researchers concerning shallow water warming ponds or water warming canals. For deep and large reservoirs which have numerical value of the ratio (N/V) greater than 10⁵ or 10⁶, diurnal amplitude of surface water temperature is estimated by the following empirical relation in Japan.
F₁-F₂/n·L^1/3=A×10² (n=4.0-5.0, N, V: M. T. S. Unit)
Where N is the total volume of reservoir and V the mean discharge of it. F₁ and F₂ denote the maximum and minimum surface heat exchanges and A the temperature amplitude in °C. L' is fetch size of reservoir expressed in km. In the case of reservirs which are equipped with surface water intake apparatus, the outflow temperature is nearly equal to surface water temperature and we can estimate diurnal amplitude of it by the above equation.

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A 1/5 scale controlled glasshouse in the Phytotron of Kyushu University has been used for the present study.
Aspirated nickel resistance thermometers have been used for measuring outside dry and wet temperatures and thermocouples for measuring temperatures in the concrete floor. For studying the radiation conditions in the glasshouse, we measured the net radiation and the solar radiation on the floor by a net radiometer and a Moll-Gorczynski solarimeter, and the solar radiation of the outside by a Moll-Gorczynski solarimeter. The volume of air which flowed in the glasshouse was measured by an orifice flow meter. We devised methods for the measurement of air temperatures in the glasshouse and surface temperatures of the glass roof inside and outside by the use of thermocouples.
Interesting results which were obtained by this investigation are as follows:
1) As to the amount of light transmitted, we found that there was clear difference of the transmission coefficient between the direct solar radiation transmitted through the ceiling and the wall (See in Fig. 1). Therefore, we would like to propose the concept of the glasshouse coefficient.
2) The main diagram of energy exchange in the glasshouse is shown in Fig. 3, in which Q_f is the total heat from the glasshouse floor, Q_a is the heat gained by the glasshouse air, Q_v is the heat due to glass temperature variation, Q_rg0 is the net radiation on the outside glass surface, Q_hg0 is the heat transmitted from the glass surface to the air surrounding the glasshouse. The amount of heat Q_f is very large, so the main energy exchange of glasshouse takes place at the floor.
3) During the night, the value of Q_rg0 becomes greater.
On another occasion we would like to study the biological significance of this phenomenon.

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To clarify the influence of the plant cover on the diurnal range of water temperature in paddy ffelds, the observations of the water and soil temperatures in both lysimeters with and without rice plants were made during the growing season of 1961 (see Fig. 1 and Table 1). The results so obtained may
be summarized as folllows:
1. The ratio, R₁/R₂, (where R₁ and R₂ are the diurnal range of water temperature in the plots with and without rice plants, respectively) was found to decrease exponentially with increasing the leaf area index, A. The values of the decreasing coefficient, charactering the reaf area index dependence of the ratio, R₂/R₁, were 0.19 for the plots with dense plants density and 0.15 for the plot with standard plant density, respectively. (see Fig. 2 and Eqs. 1 and 2)
2. As shown in Fig. 3, the ratio, Q₂/Q₁ of the heat amount stored in both water and soil layers during the half period of day (0600-1200) between plots with and without rice plant cover decreased also exponentially with the increase of leaf area index, A. The following equation was obtained from Eqs. 6, 7, 8 and 9
α₂=α₁e^(K-0.2)A(R₁/R)
where α₁ and α₂ are the storage ratio in the plots with and without rice plant, respectively, K the extinction coefficient of net radiation in rice plant communities, A the leaf area index, and R and R₂ are the net radiation on the bare water surface and on the upper surface of rice plant canopy, respectively.

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