Measurements of turbulence were carried out by use of a sonic-anemometer at several heights above and within a corn canopy with a mean height of 300cm. Turbulent intensity, autocorrelation coefficients, mixing length, transfer coefficient and energy spectra were computed for vertical and horizontal components of wind.
(1) Both √w′² and √u′² are in proportion to the mean wind velocity at each height. Above and in the upper part of the canopy, √w′² is smaller than √u′². In the middle part, √w′² is nearly equal to√u′² which may indicate the existence of isotropic turbulence.
(2) The autocorrelation coefficients above and within the canopy are calculated for vertical and horizontal components of wind fluctuation. Using the calculated values, the vertical mixing length and the transfer coefficient at each level are estimated respectively by the following equations
l_w=√w′²∫^T₀R_wdt (1)
K=√w′²·l_w (2)
where R_w is the autcorrelation coefficient for the vertical component of wind fluctuation, and T is the smallest time at which R_w becoms zero.
The values of both l_w and K above the canopy agreed well with those calculated from the log-profile of wind velocity above the canopy.
The horizontal mixing length, l_u is also calculated by use of the autocorrelation coefficient for the holizontal component of wind fluctuation.
Above and in the upper part of the canopy, l_w increases with wind velocity, but it seems independent of wind velocity in the middle and lowest part. l_u increases with wind velocity at any height above and within the canopy.
The transfer coefficient is, above and in the upper part of the canopy, in proportion to the square of the wind velocity, but, in the middle and lower part, is proportional to the wind velocity.
(3) With the values of τ and du/dz, l_w which is defined by
τ=ρl²_w(du/dz)² (3)
is obtained, τ is the flux of momentum calculated from K and du/dz. The values of l_w, from eq. (3) becomes in the canopy as large as three times of that at the top. It is therefore considered that equation (3) is not applicable in the canopy.
(4) Energy spectra of turbulence are estimated of vertical and horizontal components of wind fluctuation above and within the canopy. By expressing the spectra at high frequenciy end as
F(n)-n^p, (4)
the value of p increases with the gradient of wind velocity.
There are some developed peaks of n·F(n), which is probably due to local eddies created by plant.
A following equation is obtained for the vertical component of wind fluctuation at any height above and within the canopy
l_w·n_max/u=0.08
where n_max is frequency at which n·F(n) is maximum.

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Turbulent transfer coefficient, foliage exchange velocity and stomatal exchange velocity within a corn canopy are approached using the heat balance method. Measurements of air temperature, water vapour pressure, net radiation and wind speed were made at several levels within and above the canopy during the growing season of corn crops. Instruments presented schematically in Fig. 1 were used for the measurments.
The results obatined can be summarized as follows:
1: The exchange velocity in the interval h is given by
D_0-h=R(z₁)/cpρ(ΔT+l/cpΔq)-A,
where R(z₁)=S(z₁)-B_s; ΔT=T₁-T₂; Δq=q₁-q₂; S(z₁), T₁. q₁, net radiation, air temperature and specific humidity at height z₁; T₂, q₂ air temperature and specific humidity at height z₂; B_s soil heat flux; C_p, ρ, specific heat and density of air; l, latent heat for evaporation. A is a term for considering the influence of changes of S and K in the interval on the exchange velocity. Mean transfer coefficient in the interval is given by
K=h·D_0-h.
Preliminary computations indicate that the influence of the term A can be disregarded with acceptable errors in the canopy, provided the interval h is so small as 10cm (see Table 1). Fig. 2 shows that the transfer coefficient at the mid-point in the interval is in fairly good agreement with the mean transfer coefficient in the interval. Although the initial decrease of the transfer coefficient with the canopy depth is rapid, the decreasing rate diminishes gradually with the canopy depth. Values of the transfer coefficient at the canopy top are by one and two orders of magnitude larger than those in the lowest layer. The normalized profiles of the transfer coefficinet (K/K_H) are shown in Fig. 4. Each point is the avergae of the respective normalized values for the 10-min profiles. The mean profiles were approximated by an exponential function. The values of its extinction coefficinet vary from 2.46 to 2.88, and agree well with those presented in literatures. The extinction coefficient seems to increase slightly with the maximum leaf area density within the canopy, but it requires futher experimental studies.
2: The mean foliage exchange veloeity (D_f) in the interval of 25cm was calculated by
D_f=ΔS-ΔlE/2cpρΔF(T_f-T_a),
where ΔS, ΔlE, the divergence of net radiation and latent heat fluxes in the interval (ly/sec); ΔF, the partial leaf area index; (T_f-T_a), leaf-air temperature difference. The magnitudes of the foliage exchange velocity averaged for the daylight hours (0900-1700) are 3.8, 2.6, 1.9, 1.7, 1.0, 0.9cm/sec respectively in the layers of 275-250, 250-225, 225-200, 200-175, 175-150, 150-125cm. The absolute values of the foliage exchange velocity within the canopy are in fairly good agreement with results obtained by IMPENS et al. (1967) using a different method. The profiles of the foliage exchange velocity were also approximated by an exponential function. The value of extinction coefficient was found to be 2.8.
Fig. 6 shows the foliage exchange velocity as a function of transfer coefficient. The following relation was obtained by regression analysis
D_f=0.56+1.25·10^-3K.

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The intact measurement of leaf moisture is attempted with the transmission of beta radiation.
Transmitted radiation intensity I (cpm) is approximately represented by
I=α·I₀e^-μMt(1+u), (1)
where α=geometrical efficiency of the detection of transmitted beta radiation
I₀=incident radiation intensity (cpm)
μ=mass absorption coefficient (cm²/mg)
M_t=mass thickness of dry tissue of the leaf (mg/cm²)
u=moisture ratio of the leaf.
The moisture ratio of citrus leaves was measured using ²⁰⁴Tl as the beta ray source. The leaf was placed between the source and the detector, a G-M tube. In the course of drying the leaf was weighed and the transmitted beta radiation was counted.
Absorption curves of the beta radiation by a citrus leaf versus the moisture ratio showed that equation (1) is valid in the mass thickness range from 22 to 37 mg/cm².

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Recently so-called “Graft Carbon Sheet Heater” is produced. It is a sheet of electric resistance, that is made of glass-cloth, on which carbon black with a certain vinyl-monomer is glazed at 160°C-180°C for ca. 10 minutes.
The graft carbon sheet heater has the following characteristics:
(1) There is the clear tendency to increase in resistance with time.
(2) The surface temperature of the graft carbon sheet heater at the balanced situation is different after the setting conditions;
(a) on the concrete floor ca. 20°C
(b) on the surface of the sand bed ca. 40°C
(c) 15cm underground ca. 60°C
(3) At the balanced situation the constant temperature gradient can be found in the sand bed and the certain temperature can be observed at the certain centimeter underground.
(4) The raising effect of the gaft carbon sheet heater for the air-temperature is expected especially in a vinyl-hause.

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An index of the climatic productivity of paddy rice was firstly proposed by Murata (1964) using the average of daily mean air temperatures and that of daily insolation amounts during the productive period of rice of 40 days from 10 days before to 30 days after heading time. However, the yield is affected by climatic conditions during the whole growing period of the plants. Therefore, we attempt to look for the index which contains climatic elements covering the whole growing period. We already analysed the relationships between climatic conditions (air temperature and duration of sunshine) and ripening with in 40 days after heading time, and obtained a climatic index ripening, Y_G.
In this report, we have analysed the relationships among the rice yield, the daily mean air temperatures, θ_6·7 and the total durations of sunshine, S_6·7 by Jordan's recorder in the main growing areas in the northern districts of Japan for June and July, namely, transplanting period and heading time. Yield is affected considerably by θ_6·7, but not by S_6·7, as shown in Fig. 1. Thus, the lowest critical conditions of rice yields, 400, 500, 550kg/10a, could be obtained from the relations among θ_6·7, S_6·7 and yeields in Fig. 1, a yield of 500kg/10a may not be attained below the critical curve of 500kg/10a at all.
Further, the relationship between θ_6·7 and Y_G is analysed, and a θ_6·7-Y_G co-ordinate which indicates the climatic conditions during the whole growing period is constructed. The climatic data of each area in the northern districts of Japan in recent years are plotted on this coordinate with yield data. Three critical curves mentioned above are obtained using the same method as in Fig. 1 (Fig. 2). Fig. 3 shows the relative situation between the values of the co-ordinate for normal years in these areas and the critical curves. It is considered that the greater is the diffeerence of the relative situations between the normal yield and the critical curve, the greater is degree of inhibition of yield by other factors than climatic ones.

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Recently, also in the warm region Kyushu, which is situated in the south-western area of Japan Islands, a local snowfall has become one of the important meteorological phenomena in winter, since snowfalls have many influences upon agriculture, trasportation, especially in the high-way road which nowadays is going to develop, water resources and so on. The authors have investigated snowfalls by means of the climatological analysis and general synoptic analysis, and had a chance to observe the natural snow crystals and snowflakes associated with the snow clouds developed in the north-west monsoon period, Feb. 5th to 7th in 1969. The snow crystals and flakes were observed with the method of the macroscopic sketch, the replica observation, the close lens camera, and the photographic recording. By those analyses described above it is found that when we have much snow in Kyushu where usually the snowfall occurrence is very rare and its amount is very little, the synoptic conditions and the pattern of snowfall distribution are quite similar to those when the heavy local snowfalls occurred in the coastal regions of Japan Sea. Results of analyses are summarized as follows.
1) In large scale synoptic situation, when the cold and dry air mass from the Siberian Continent comes down southward near the northern part of Korean Peninsula and then passes over the Japan Sea, it is modified with heat and vapor from the sea water below and becomes an unstable air mass.
2) The occurrence of snowfall is characterized by the strong wind zone near the 850mb level. This corresponds to the strong curvature of wind profile explained previously by Higuchi.
3) In meso scale synoptic situation, local lines of convergence appear along the north and south-west coast of Kyushu. Those are made due to the cooling effect of radiation in the inland area and increases in the rate of precipitation.
4) Types of Radar Echoes observed support that the snow clouds are convective ones and show their band structure which is characteristic to local heavy snowfalls in Hokuriku and Hokkaido.
5) Snowfall distribution shows that much amount of preciptation is seen rather in the lower plain, and this is quite similar to local heavy snowfalls in the coastal region of the Japan Sea.
6) Snow crystals observed at Mt. Hiko are almost consistent with the expected ones by Nakaya's Ta-S diagram.

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The agriculture in Japan, especially in western Japan, suffers from flood damages.
In this paper the author investigated the property of the heavy rains during the period from 7th to 10th of July 1967, recording the total amount of precipitation over 300mm in the north-western Kyushu, including the region of Nagasaki and Saga prefectures. Many severe flood damage landslides and their related damages occurred owing to the rainfalls.
The results of the investigation from the standpoint of the local scales are as follows:
(1) The heavy rains are composed of concentrated heavy rain caused by mesoscale disturbances passing along the Baiu front and of that associated with a low pressure.
(2) The rain area is composed of 3 zones which stretched out from western Nagasaki to the Seburi mountains. The scale of rain cells (area) is about 10 to 20km in diameter and their intensity are at most 20-40mm per 10min.
(3) In the later part of this paper, the author makes a survey of landslids, and occurrence of landslide related to the rainfall. The author suggests that the landslides are more closely related to heary rainfalls of 20mm/10min than hourly and daily rainfall.

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