The possibility of warming the flood water in paddy rice land by suppressing evaporation from the water surface was previously confirmed by one of the authers and his colleagues.
In response to our request, n-docosanol (C₂₂H₄₅OH) has been synthesized by M. Suzuki from, first, octadecanol (C₁₈H₃₇OH) and next from the rape oil. However, having scarecely surface activity, Docosanol was combined with oxyethylene (CH₂CH₂O) at various rates of amount to get high spreading power. A lot of samples were made and supplied to the tests of spreading power and suppressing ability of evaporation.
In this paper, best two kinds of oxyethylene glycol, C₂₂H₄₅OCH₂CH₂OH and the mixture of C₂₂H₄₅ OCH₂CH₂OH and C₁₈H₃₇OCH₂CH₂OH, are compared with two alcohols, C₁₈H₃₇OH and C₁₆H₃₃OH, in regard to the surface pressure and suppressing power of evaporation. The formers show 30-70% higher suppressing power than each of later two when they cover the water surface with their mono-moleculer films.
In particular, C₂₂H₄₅OCH₂CH₂OH shows extremely high ability in the temperature range of 20 to 30 °C, reducing evaporation to blow 10% of that of free surface water. The mixture of two glycols indicates high ability of suppression even in the range of low temperature in which C₂₂H₄₅OCH₂CH₂OH hardly suppresses the evaporation. So called OED, made of the mixture glycols above mentioned, is now being put in practical use by rice growers for the purpose of warming the cold standing water and of advancing the growth of rice.

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筑後の三潴地区の一大特色であるクリークは, 現在の稲作と将来の国土利用の観点から重要な問題を包蔵しているので, その水温の解明を主目的に気象観測を1958年9月初めに実施した。クーリクは標準的規模である。
i. 水温は深さと時刻で決まり, クリークの中央や岸近くなどの位置的な差は少ない。
ii. 水温の時間的変化の明らかな範囲は1mより浅く, 直径25cm白円板の見えなくなる0.7m前後にほぼ近い。
iii. 当時は表暖底冷型 (日平均で表面29℃, 水底2.3mは26℃) であり, また一般地中や稲田よりもクリークは高温で, 初秋になお夏の熱が保持されている。
蒸発量や水面付近の諸要素の測定が不十分なため熱収支表は完成し得なかつたが, 予習的な目的は達した。
観測には著者らのほか, 九大農学部気象学教室の松田・高田, 九州農試気象研究室の船橋・日吉・中村, 福岡県農試筑後分場の森山・松岡・松永・井寺・中村の諸氏が従事した。筑後分場からは種々の御便宜をはかつていただいた。諸氏ならびに分場に深謝する次第である。
なお報告の取りまとめは主として佐藤が行なつたものである。

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The transmissivity of black body radiation through smoke layers was calculated by the formula (1).
The temperature of black body is 300°K, and the properties of smoke droplets are assumed as follows; droplets radii; 0.65μ·0.80μ·0.95μ·110μ, the ratio of droplets numbers; (0.65):(0.80):(0.95):(1.10)=3:4:6:4, complex refractive index; as in Table 4.
The efficiency factor for extinction “Qext.” are calculated at first by means of Aden's method, the result is shown in Fig. 2. Then the transmissivity are calculated and shown in Fig. 3. The calculated transmissivity was in coincidance with the experimental one.

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This investigation was made in 1958 to estimate the amount of damages to be done by the prevailing easterlies to the rice yield in the area at the leeward of the windbreak on the seashore near Yamoto Town, Miyagi Prefecture, as a result of the cutting-down of the forest for the purpose of enlarging the landing strip of Matsushima military air depot.
The outline of the information I have obtained on the effective limits of the windbreak and the estimated distance distribution of decrease in rice crop, will be given below.
(1) On the map I drew two lines (A) and (B), one on the paddy fields exposed to the breeze and the other on the paddy fields at the leeward of the shelter-belt of trees. The measuring spots were placed at every 100 meters on the lines. The comparison was made between the rice yields at the corresponding spots of each line, and the difference between them was considered being made by the shelter-belt of trees. The same comparison was made at the area on the other side of the air depot. For comparison at the measuring spots I used the average rice yield per 10 a figured out by the Yamoto Agricultural Insurance Association.
(2) The effective zone of the windbreak on rice yield was found out having a radius of about 400 meters from the forest, in other words, a screen of trees gives useful shelter to about a distance of thirty times its height. This finding was in accord with the calming effect of the forest measured by the Sendai Meteorological Observatory.
(3) In case when the windbreak is cut down, it can safely be guessed that between the distance of the forest and the rice yield will be formulated by the following equation (see Fig. 3):
Y=0.07x+68 (σ=2.2)
Therefore, after the windbreak has been destroyed, the paddy fields near the forest are supposed to show about 30 percent decrease in production as compared with the non-effective site. The decrease percentage increases with the distance—about 7 percent every 100 meters—and at a point 400 meters from the screen of trees, the rice production comes to be free from the influence of the forest.

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The stems of rice, wheat and barley plant are dealt with dynamically as beams of pipes which are fixed at lower ends, and their stiffness to bending and bending moments of breaking are calculated with the data measured by Ezaki (1959).
Using these values and shearing stress of wind at the ear height, the relationship between wind speed and displacement of ear is obtained. When the wind speed at 1.5m height is 10m/sec, it is found that the ears of rice plants are pulled about 10cm to leeward as a mean condition.
When the wind blows with the speed of 20m/sec and full length of a rice plant is about 84cm, the bending moment caused by wind force at the lowest part of the stem is about 335gcm, and displacement of ear is about 40cm. The bending moment caused by gravity is 232g cm, and this is added to above, and, thus, the bending moment at that part is 567cm. However, for the breaking stem the necessary moment is about 2, 000gcm as shown in Table 1, and the usual wind can not break the rice plant.
This fact seems to be unreal, judging from following reasons:
(1) These wind speed is expressed in a mean value in general and it may reach instantaneously about two times as strong.
(2) The strength of stem is made weak by bad conditions such as rain, disease or malnutrition.
(3) Stems are fatigued by repeated loads.
If the load by wind force becomes twice as much and the strength decreases to a half, the stem must be broken down at the low part.
According to the equation of inverted pendulum, the period of rice plant vibration soon after earing, is estimated about 0.7 seconds, and the passage time of largest turbulons at the ear height is about 0.6 seconds when the wind speed at this height is 4-5m/sec.
Both of them coincide with each other at this wind speed, and the plants resonate and the amplitude increases extremly.
The possibility of lodging by resonance is suggested.

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Researches of local climate prerailig over a slope orchard were very important both for the fundamental projects of an orchard and for the adequate managements of their environmental conditions.
We have, therefore, made temperture and wind measurements on the 38 stations over the whole area of Atagawa orchard of our University during several days of summer and winter for these two years.
Temperature distribution diagrams for morning, noon and evening have shown their characteristic patterns by weather which were shown in the figures and in the tables.
Windroses of daily prevailent wind by day and night at four stations in our orchrd were drawn in Figure 6 which have depictured remarkable features of surrounding surface conditons.
As the results of our measurements, we connot afford to overlook the functions of windbreak for the control of local climate in our orchard.

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We made micrometerological observations on the paddy field during 6-7 August (growing stage of rice plant), 21-22 September (riping stage) and 27-29 November 1959 (after harvest), respectively. The paddy field situated at the north west corner of Kanto Tosan Experiment Station, Konosu, Saitama Pref., but was under no so good conditions for our observations.
Ten small Robinson anemometers, six thermojunction thermometers and psychorometers were used for measurements of wind speed, temperature and humidity profiles, and profiles of CO₂ concentration and the net exchange radiation were measured simultaneocusly, too.
At first, d and z₀ are decided from the wind profiles under neutral condition. The results are shown in Figure 1, and after harvest the field has z₀=0.6cm.
The relationship between wind speed and zero plane displacement is adopted to other nonneutral condition, and wind speed U, air temperature θ, absolute humidity χ, and CO₂ gas concentration c at each heights ploed on semi-logarithmic graph-paper. The measured values at three heights taken as 2(z₁-d)=(z₂-d) and 2(z₂-d)=(z₄-d), are read on these papers, and momentum fluxτ, sensible heat flux F, vapour flux E, and CO₂ flux P are obtaind by following equations:
τ=4×10^-4×{2(U₂-U₁)-(U₄-U₂)}² dyn cm^-2,
F=-0.959×10^-4×{2(U₂-U₁)-(U₄-U₂)}{2(θ₂-θ₁)-(θ₄-θ₂)}cal cm^-2 sec^-1
E=-0.333×{2(U₂-U₁)-(U₄-U₂)}{2(χ₂-χ₁)-(χ₄-χ₂)}g cm^-2 sec^-1,
and P=-0.333×{2(U₂-U₁)-(U₄-U₂)}{2(C₂-C₁)-(C₄-C₂)}g cm^-2 sec^-1.
When the free convection prevails in midday, these equations can not be applied. Using values of U, θ, and χ at the height extremely close to roughness height z₀, (z-d)<2z₀, fluxes can be obtained by other equations such as
u²_*=(kU/u1z-d/z₀)²=KdU/dz, F=-C_pPKdθ/dz=-C_pρu²_*dθ/dU, and E=-Kdχ/dz=-u²*dχ/dU
By means of these equations, fluxes can be obtained as shown in Table 1. However, calculated fluxes seem somewhat too small, and it is supposed that the reasons of underestimation are due to
(1) errors of anomometers, thermometers and psychorometers at very low wind speed,
(2) the error in d, (3) the unsuitable location of the site, and
(4) the intermittent nature of our meassurements which were carried out only 10 or 20minutes for one hour. On the other hand, the ratio E/P corresponding to water requirement of crop was calculated as 200-300, which coincides fairly well with known value. Heat balance over the field is calculated as
R_n=F+lE+λP+Q+X,
where R_n is net exchanger radiation, F sensible heat transfer, lE latent heat by evapotranspiration, λP latent heat by assimilation of carbon dioxide, Q storage heat in the crops and X remainder being mainly soil heat flux. The results are shown in Figure 2. λP and Q in right hand are so small that they are negligible, and X is too large to consider to be only soil heat flux. The cause of these anomalies seem to be dependent upon the underestimate of fluxes above the ground.

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