The author estimated the soil moisture at Owada, from the potential evapotranspiration, the function of the air temperature. and the amount of precipitation, by Thornthwaite's method.
Fig. 1 shows an example of soil moisture, observed by drying method and estimated from climatological data. Observed data show the observed soil moisture of the bared land, and estimated data show the estimated soil moisture of the land with vegetation. In winter, estimated soil moisture are nearly 95-100%, but observed soil moisture change remarkably. In summer, as a general rule, both soil moisture change similarly way. Only in midsummer (July and August), the estimated data are smaller than the observed data. Because in this season, the transpiration by vegetation is very large, and the evaporation from the bared land is prevented by the mulch of dried soil.
Fig. 2 shows the seasonal change of the soil moisture, Fig. 3 shows the variability of the soil moisture, estimated from potential evapotranspiration. The variability or the range of soil moisture variation, is in maximum, 100%, and the mean value is very small in July, August and September. Because in this season drought occur very often, and sometimes, soil is saturated with water, as it rains heavily. In the last decade of June, as it rains heavily, so the mean of soil moisture is large and the range of variation is small. In winter, mean value is very large and range of variation is very small, because the soil moisture is always nearly saturated with water, as the transpiration by vegetation is very small in this season.

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The Carbon-Black Powder was dusted on the water surface in the paddy field to intercept the penetration of solar radiation into the water, and the rice-yields of the Plot were the most among three Expt-Plot. (See Tables 2, 1, & Fig. 1)
The reasons of the results may be as follows:
1) The soil-temperatures were moderate in summer.
2) Few weeds grew in the field for lack of the light in water.
In Straw-Mulching Plot, the fungus diseases occurred and the rice-yields were the least in spite of moderate temperatures of the field.

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Carbon dioxide was microclimatically measured, for it is one of enviromental elements which influences to cucumber plants.
Carbon dioxide concentration in the air was determined with a Haldne gas analyzer, which was sunk in a water bath to lessen the analysical errors caused by temperature. The results of the experiment are summarized as follows:
1. When the hot cap and the cold frame bed, where young cucumber plants were planted, were investigated, it was found that the former contained more carbon dioxide than the latter, and that the cold frame was more easily influenced by the weather.
2. The gas concentration in the cucumber field was measured in the daytime under various weathers. The gas surrounding the cucumber vine showed the lowest concentration at 10a.m. on fine days, but it increased in concentration after that time. On rainy days, there was the inverse tendency in the gas concentration.
3. The fluctuation of carbon dioxide concentration in the course of a day was investigated at various heights of the cucumber vine. The result was that the maximum concentration at every height occurred at 10 p.m., and that the minimum at 6p.m. The fluctuation at various heights seemed to be much the same as that of the middle height.
4. The carbon dioxide, which is released from the leaves and the soil surface of the cucumber field, affected to the carbon dioxide concentration of the air. The maximum amounts of the gas from the leaves and the soil surface were found at 10p.m. and it coincided with the maximum concentration of the gas surrounding the vine. The minimum concentration of the gas there came 2p.m. The reason is supposed to be that in the daytime, the gas released from the leaves and the soil surface decrease in amount and there occurs assimilation.
5. When the distribution of carbon dioxide concentration in the cucumber field was investigated, it was found that the concentration was much the same in every part at the midday, about the sunset and at the midnight, and that the concentration was higher in the west side of the vine than in the east side about the sunrise.

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Although the preventive function of a wood-belt against frost damage has long been studied and discussed, no conclusion has yet been gained.
We made some tests on a level ground using pine-branch hedges and board fences with various covering degrees and numbers of rows, and existing shelter-belts and farmwood.
The keeping-warm effect of a wood-belt is found as 2 times the height of the trees when the covering degree increases; and the wider the wood-belt, the larger gets the range where the effect prevails. But in the case of a board fence, though it is found that the temperature becomes high as far as 1.5 times the height of the hedge in the lee even when the covering degree is 100, it is not so warm as in the case of a wood-belt. Instead, a lower temperature zone appears in the range 1.5 times the height toward the wind and 3 times in the lee. When the covering degree of the board fence is 50, keeping-warm effects are hardly recognized.
In the daytime when the wind velocity is low and it is fine, it gets warm near the hedge in the lee, and the heat is left over into the night and relieves remarkable fall of the temperature. In the night-time when it is cloudy and the wind is more than 1m/sec, little variation is recognized in temperature in front and back of the hedge.
The keeping-warm effect of wider shelter-belts or farmwoods reaches as far as more than times the height of the 3 trees in the lee, and the extent the temperature rises gets wider. In the period of late frost the keeping-warm effect of a wood-belt greater when it is of needle-leaf trees than of broad-leaf ones.
This is perhaps due to the fact that the leaves of the broad-leaf trees have run only 50 to 60 per cents and the crown density is smaller.
The results of the investigation into late frost damage with indication plant (5 to 8-leaf sweet potato runners) show that the preventive effect is greatest in a 4 row pine-branch hedge and is smallest in a board fence with the covering degree of 70.

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The author carried out the observations of the diurnal variation of plant temperatures of grapes and egg plant, temperature of sweet potato and stem temperature of paddy rice from August to October in 1952 and also fluctuation of stem temperature of barley in March, 1956.
The temperature of each plant were measured with copper-constantan thermocouples (diameter is about 0.15-0.2mm) being recorded by a potentiometer and galvanometer in 1952 and oscillo-graph in 1956. A junction was inserted in fruits, sweet potato and stem. The date, plants, weathers and instruments of measurement are shown in Tab. 1.
The results obtained are as follows;
(1) The diurnal change of sweet potato temperature compared with soil temperature near the soil surface is shown in Fig. 1 (A). In the day time, it is shown that soil temperature is the highest and temperature of central part of sweet potato is the lowest, and the reverse is shown in thenight. But differences of temperature between soil and sweet potato are small of about 1°C in the daytime and 0.1-0.2°C in the night.
(2) The change with time of stem temperature of paddy rice after the pouring of cold and hot water is shown in Fig. 1 (B) and (C). It is recognized that differences of temperature between water and stem vanish within 3-4 minutes.
(3) Diurnal change of temperature of egg plant fruits compared with air temperature is shown in Fig. 2 (A) and Tab. 2. In the daytime, it is recognized that the temperatures of the surface and of the central part of fruits are higher than air temperature with differences of 10°C and 5.5°C, respectively.
There seems to be no doubt that this higher temperature is dependent on the solar radiation.
(4) Diurnal change of temperature of grape fruits compared with air temperature is shown in Fig. 2 (B) and Tab. 2. It is shown that in the daytime temperature of grapes shined by the direct solar radiation is very higher than air temperature with differnces of about 5.4°C. But in the night, temperature of the grape is cooler than air temperature, and it seems that this cooling is dependent on nocturnal long wave radiation from fruit surface. However, temperature of fruits covered with leaves and stems is nearly equal to air temperature, and this is due to the protection of solar and nocturnal radiation.
(5) Stem temperature of barley and air temperature at about 5cm high from the soil surface were recorded by the oscillo-graph, and then, Eulerian correlation coefficient (R(t)_T) and spectrum were calculated from 180sec. recording as shown in Fig. 3 and Fig. 4, respectively. The Eulerian correlation coefficient curve is shown to fit the relation
1-R(t)_T∞t^4/3
within the range of small lag and this coincieds with theoretical result by Inoue. From Fig. 4, it is recognized that w(λ) of stem temperature vanishes at large λ, but w(λ) of air temperature does not.

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The relation between the transmissivities of heat and water vapour of the frame paper and the temperature in the rice seeding bed was studied.
Five kinds of frame paper, the transmissivities of which differed from each other were prepared and used to cover the rice seedling beds respectively. This experiment was done at two periods, 6-19th April and 6-17th May.
The temperature at various depthes under the paper and general climatic factors were measured for above periods.
Daily maximum ground temperature at seeded layer (about 1cm in deep from the bed surface) is directly proportional to the daily maximum air temperature, and the values of proportion coefficient “k” on five beds were adopted as the indicators of warmth keeping power of each paper, and they were shown in table 2.
The relationship between the values of “k” and three physical properties, heat transmissivity, water vapour transmissivity and aeration is shown in Fig. 3. It shows the water vapour transmissi vityis rather more effective on the warmth keeping than heat transmissivity, and that the aeration of paper has no relation to the heat budget.

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A maximum-minimum thermometer named N types one by the author, which can measure at a distance the maimum and minimum temperatures in soils, powder, water, solutions, boxes, chambers and so on was newly planned by means af improving the SIX's maximum-minimum thermeter and was manufactured for trial (See Fig. 1 and 2).
Also the diurnal maximum and minimum humidities can be measured by useing a pair of these thermometers which one is used as wet bulb thermometer.

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