Characteristics of the transpiration from a taro leaf is studied based on a field experiment. The transpiration from a single leaf was measured by a weighing procedure. The bulk transfer coefficient of the transpiration (C_s) determined using surface saturation specific humidity was found to have a constant value during the daytime within a single day, but to decrease as the plant life approaches to an end. The moisture availability defined as the ratio C_s to the coefficient for the sufficiently wet leaf surface was found to be about 0.7 in the daytime and near 0 in the nighttime.

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A dynamic model describing relation between fruit growth in Japanese pear (Pyrus pyrifolia Nakai) and solar radiation was developed. The model is based on observations on fruit volume under controlled solar radiation in an orchard.
Japanese pear cv. ‘Kosui’ were grown under seven solar radiation levels controlled with some kinds of cheesecloth from fruit thinning to harvest in 1989. Fruit volume were measured every week or every two weeks. The harvesting date decided from ground color was not influenced by solar radiation level. But fruit growth since 33 days after flowering depended not only on solar radiation but also on fruit volume of 33 days after flowering (V_t); Fruit growth for any growth stage was proportional to V_t^p(p=0.580) regardless of solar radiation levels in any growth stage. That was proportional to S_n^b(b=0.639) also in any growth stage, where S_n is solar radiation for the growth stage. From the facts we deduced a model as follows:
FVGR=k_n⋅S_d^b⋅V_t^p
where FVGR (fruit volume growth rate) is daily fruit volume growth, S_d is daily solar radiation and k_n is parameter which was calculated using the equation and observed values (FVGR, S_d, V_t). The k_n indicating the influence of solar radiation on FVGR changed in every growth stage. The following equation can be used to estimate the fruit volume at x days after flowering (V_x).
V_x=V_t+Σ^x-1_d=33FVGR_d
In order to test the validity of the model and parameters (k_n, p, b), Japanese pear cv. ‘Kosui’ were shaded during four different growth stages with one kind of cheesecloth in 1990. They were justified by comparisons between the observed growth curves and those estimated from the model, parameters and observed daily solar radiation.

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In this paper, we use fussy cluster analysis to explain the types of dry summer in the Fukuoka area and the characteristics of the areal distribution of the agricultural meteorological disasters in the Chugoku and Shikoku districts.
For dry summers in the Fukuoka area, we take six climatic indexes as the standard classification, including the ratio to the normal of the sum of monthly amounts of precipitation for June, July and August. Three types of dry summer are classified and the magnitude differences of the levels of dry summer are explained from the view point of the moisture and temperature. In regard to agricultural meteorological disasters in the Chugoku and Shikoku regions, we take the occurence times of seven types of meteorological disasters as the standard classification, such as damage by wind, flood damage, drought injury, snow damage, freezing damage, cool summer damage, hail damage and frost damage, from 1971 to 1984. Five disaster areas are classified and the characteristics of the areal distribution of agricultural meteorological disasters are identified. The analytical results show us that the Fussy Cluster Analysis is usefull for explaining characteristics in the field of agricultural meteorological disasters.

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The effects of covering cabbage crops to prevent cold injury were investigated using cheesecloth made of Vinylon.
Two types of cheesecloth, #200 and #300 were used. The floating row cover method in which the cheesecloth is at a height 50cm above the ground and the contacting row cover method in which the cheesecloth is kept just above the top of the cabbages were employed.
The air temperatures under the floating and the contacting row covers, using cheesecloths #300 and #200 were 3°C and 2°C, respectively, higher than that of the control during clear nights with wind speed below 50cm/s. However, with increasing wind speed the difference between the air temperatures in the control and the row covering were slight especially in the contacting row covering, using #300. The leaf temperatures under the floating row cover with #300 and #200, were 3°C and 2°C, respectively, higher than the control when the wind speed was less than 50cm/s on clear nights. With increasing wind speed over 100cm/s, there was no difference between the leaf temperatures in the contacting row cover with cheesecloths #200 and #300, and that of the control. However, there was a difference between the leaf temperatures in the floating row cover with #300 and the control. In the case of the contacting row cover, the leaf temperature increased slightly under #200 and #300, leading to a small temperature difference between the contacting row cover and the control.
These results show that the floating row cover with cheesecloth #300 was useful irrespective of wind speed. The incidence of head rot caused by cold injury under the floating row cover with cheesecloth #300 was lower than it was in the control in open field. The contacting row cover and the floating row cover with cheesecloth #200 were ineffective.
The influence of the height of the floating row cover with cheesecloth #300 on keeping the leaf temperature higher by taking off or retaining all the sides of cheesecloth was investigated. Leaf temperature under the floating row cover, stretched 30cm above the ground was about 1.5°C higher than that of the control when the wind speed was less than 50cm/s on clear night. However, the difference in leaf temperature was counterbalanced when wind speed was more than 1m/s. When the cheesecloth was ctretched 50cm and 1m above the ground, the leaf temperature was about 2.5°C higher than that of the control irrespective of wind speed. With increasing wind speeds of more than 1m/s, the leaf temperature under the cheesecloth stretching 1m high was about 1°C higher than that at 50cm.
By covering all sides with cheesecloth #300 stretched at 50cm high, the leaf temperature was about 1°C lower than that it was without the side cheesecloth.
These results indicate the advantages of choosing cheesecloth #300 rather than #200, and stretching the cheesecloth at a height greater than 50cm in order to effectively prevent cold injury to cabbage crops in the open field.

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To clarify the effects of water blooms on the heat balance in a water body, some heat balance components were observed in a small water pond (length and breadth of 160cm; depth of 45cm) made of polystyrene board of 15cm thick.
Floatage of stratified water blooms increased the albedo on the water surface but decreased the net radiation in daytime. The water temperature near the surface was increased in daytime, and decreased in nighttime as a result of the floatage of water blooms. The amount of heat storage in the water body was reduced by the stratified water blooms, because of suppressing effect for transmission of solar radiation into the water body. The amount of latent heat flux was increased in daytime by the stratified water blooms but decreased in nighttime depending on the lower water surface temperature and the reduced heat storage in the water body.

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