By using a lysimeter, a long term observation of evaporation from the well wetted soil surface was carried out at Miyazaki Agricultural Experimental Station in the southern part of Kyushu.
The author compares this value with those estimated by heat balance and combination methods. The results may be summarized as follows:
1) Temperature difference between the soil surface and air at the height of 150cm is positive in the winter season.
2) Daily mean evaporation is 1-2mm/day in winter and 3mm/day in summer. The maximum value reaches 7-8mm/day, and the yearly one is about 900mm.
3) The ratio of evaporation measured by the lysimeter to that from small pan evaporimeter (20cm in diameter) is about 0.8. The ratio may be used for an approximate evaluation of evaporation from moist bare soil.
4) Sensible heat transfer coefficient shows the seasonal change with the range of 1-3×10^-4ly/sec^-1°C. Bowen's ratio obtained by heat balance method is somewhat different from that calculated from Eq. (8). The large discrepancy between the values in winter may be ascribed to overestimation of evaporation by the lysimeter. Bowen's ratio is shown as a function of the dryness factor of the soil surface and of net radiation (Eq. 9 and Fig. 2).
5) The relation between the sensible heat of evaporation lE_s and net radiation S_s is obtained as
lE_s=0.78S_s+25.
This relationship implies that more than 80% of net radiation is consumed by evaporation in all seasons.
6) The measured evaporation is compared with that by the heat balance method (Fig. 3). Fairly good-agreement is found between the two values.
The combination method, which is incorporated with the dryness of the surface is also used for evaporation evaluation and yields a value in fair agreement with that by heat balance method.
By the heat balance and the combination methods the evaporation from the bare soil can be evaluated by making use of climatic data.

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Using several tensiometers commereially available in Japan, the author examined the effects of water amount on the time-lag of tensiometer's reading and on the relation between moisture content and tension. The structural character and amount of water which is required in changing a division on the reading are shown in Table 1.
The instrument which requires larger amount of water showed longer time-lag of reading and wider hysteresis loop than that of less amount of water. This tendency is intensified especially in the dry state of soil.
The disparity of water amount in various types of tensiometer may be attributed to the structural character of instruments such as type of manometer, connecting tube and area of cup surface. The betterment of these parts will improve the efficiency of the tensiometer.

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In order to determine the photosynthetic fixation of carbon dioxide by corn plants the carbon dioxide fluxes within and above the crop were calculated from CO₂-profile data and integral exchange coefficients obatined by heat balance analysis. An infrared gas analyzer was used to measure the CO₂-concentration at nine heights within and above the crop. All the measurements were made over 10 minute periods throughout the daylight hours (0600-1800). The observations were carried out seven times at the interval of about 2-weeks during summer of 1966.
The calculated flux of carbon dioxide of a ten minute mean basis is presented in Fig. 1. An important fact is that the time course of the downward CO₂-flux (P_H) above the crop is in fairly good agreement in the phase with that of imcoming short-wave radiation on each day except on July 14. The CO₂-flux above the dense crop reached about 30×10^-8g CO₂/cm² sec at the noon on a clear day, agreeing well with results reported by LEMON (1963). The total fixations for the hours of daylight were approximately between 4.98 and 8.90mg CO₂/cm² period.
The CO₂-flux (P_s) from the soil beneath the crop was calculated using the carbon dioxide data and integral exchange coefficients in Eqn. (1) and found to be about 10-20% of the total fixation of CO₂ by the crop over the hours of daylight (see Table 2). This indicates that the soil beneath the crop is behaving as an important source of carbon dioxide. The values of CO₂-flux were plotted against the temperature of the soil surface in Fig. 5. The points show a power relationship (P_s=P_so⋅Q^T/10).
It is evident from Fig. 2 that while the points are relatively scatter, the fixation of CO₂ and the radiation intensity relationship obtaind by the bulk aerodynamic method is in accordance with that obtained from Eqn. (7). Photosynthetic efficiencies were calculated and found to range between 3 and 7% with the mean value of 5.1% (see Table 2). Transpiration coefficients (∑E_T/α∑P_T) during the hours of daylight were between 40 and 90. The values presented here were considerably low comparing with those obtained from the measurements of the drymatter and the transpiration during a longer period. Elucidating the main cause for the discrepancy between them is an important problem in production ecology for which further investigations are needed.
The height distributions of the CO₂-flux and of the photosynthetic fixation of the carbon dioxide at several heights within the crop were presented in Figs. 7 and 8. Fig. 7 demonstrates the importance of the upper leaves in the CO₂-fixation, particularly in the crop with dense canopy. The 0.6-1.0 zone of z/H accounted for most of the CO₂-fixation between 50 and 70% of the total fixation during the hours of daylight. The midday profiles of the CO₂-fixation intensity of the leaves were characterized by the establishment of a layer with the high intensity in the center of the crop. The relatively low intensity in the CO₂-fixation of the upper leaves at the midday seems to be caused by the imbalance of water in the leaves exposed to high intensity radiation.
In order to characterize the efficiency in water use of the leaves, the height distribution of the layer's transpiration coefficient (ΔE_T/αΔP) was calculated and given in Fig. 9. The values of the transpiration coefficient decreased with the depth from the top to the middle level. Below the middle level the coefficients were found to go up again with the depth. The height distribution of the coefficient is thus concave to z-axis. This feature indicates that the water use of the upper and lower leav

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The date of the first snowfall, the date of the last snowfall, the number of days of snowfall and the maximum depth of snow cover are the most popular climatological data. But it is questionable that these data are usefull to lay plans in various industries as well as in agriculture.
Therefore, the seasons and the geographical distribution of heavy snowfall in Shikoku District are investigated. In Shikoku District, the snow cover generally soon melts away, but by districts or years, it covers the ground for a period of time, and the same phenomena as are called NEYUKI (continuos snowcover) can be recognized, The statistics of the probable maximum snow depth are better fit for climatology in the District.

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