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Volume 16, Issue 3
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N. TANI1960 Volume 16 Issue 3 Pages 89-93
Published: December 30, 1960
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSSince 1951, wind profiles over the cultivated field were observed, and now some empirical results are obtained from these data.
Six or ten small Robinson anemometers, and six aspiration type thermometers and psychrometers were used for the measurement of profiles. These instruments were installed between crop height and about 6m above the ground.
Among many data, those obtained in September are selected.
The wind profile over the paddy fields under the nearly neutral condition can be represented by
U(z)=u*/k(lnz-d/z0+βz-d-z0/L) (1)
where d is zero displacement, L stability length and β a constant (Ogura 1952, Monin and Obukhov 1954). It is known that d and z0 vary with wind speed U (Deacon 1949, Rider 1954). At first the observations made under almost neutral stability condition are selected, and d and z0 are determinded graphically. The relationship between wind speed at 1.5m above the ground and d is shown in Figure 1. It is divided into three regions as follows:
A. (0-2m/s at z=1.5m)d decreases and z0 increases, because light wind bends only the top of leaves and ears and can not penetrate into the space under the ear layer.
B. (2-4.5m/s) d increases and z0 decreases. Slightly stronger wind shakes leaves and stems of crop. The prevailing period of the fluctuating wind is close to the period of vibration of crop, and crops obstruct the penetration of wind.
C. (above 4.5m/s) When the very strong wind blows, the crop bends deeply and effective height of crop decreases.
The fact pointed by Deacon and Rider seems to corresponding to “B” region.
β in equation (1) was given 0.6 by Monin and Obukhov. However, these observations give 5.30 as a mean value. (Table 1).
Taking wind speed U, temperature θ, and absolute humidity χ at three height Z1=z1-d, Z2=z2-d, and Z4=z4-d, and 4Z1=2Z2=Z4, then β and L in equation (1) are eliminated and sensible heat flux F and vapour flux E can be obtained by following equations:
F=-cpρk2/(ln2)2{2(U2-U1)-(U4-U2)}{2(θ2-θ1)-(θ4-θ2)} and E=-k2/(ln2)2{2(U2-U1)-(U4-U2)}{2(χ2-χ1)-(χ4-χ2)} The results calculated with these equations are shown in Figure. 2.View full abstractDownload PDF (645K) -
(7) On the Relation between the Voltinism of the Antheraea Pernyi G. and the Meteorological ElementsK. NISHIMURA1960 Volume 16 Issue 3 Pages 94-98
Published: December 30, 1960
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSHaving kept the Antheraea pernyi every years, we got many univoltine pupaes in 1948 and 1956, and many bioltine pupaes in 1949. Then we made studies of the weather conditions and of the characteristics of cocoon among those years, and obtained the following conclusions:
(1) The temperature during the egg stage, the 1st instar of larval stage and the pupal stage in 1948 and 1956, was lower than in 1949, but on the contrary, during the 2nd∼5th instar of larval stage was higher
(2) The humidity during the egg stage, the 1st inster of larval stage and the pupal stage in 1948 and 1956, was higher than in 1949, but during the 2nd∼5th instar of larval stage was lower. (3) The sunshine hours during the egg stage and the pupal stage in 1948 and 1956 were much less than in 1949, but during the larval stage they were contray.
(4) The amount of precipitation during the egg stage and the larval stage in 1948 and 1956 was much less than in 1949.View full abstractDownload PDF (755K) -
Part. 1 Relation between the Regionality of Climate and Growth of Rice Plant in Aomori PrefectureI. ABE, K. ONO, K. TORIYAMA, J. WADA1960 Volume 16 Issue 3 Pages 99-105
Published: December 30, 1960
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSIn 1957 and 1958, the experiments were carried out to make clear the relationships between the regionality of climate and growth of rice plants in Aomori Prefecture.
The results are summarized as follows:
1) There were close relationships between the regionality of climate and the growth of rice plants. The regional differences in climate were larger in 1957 (cold summer) than in 1958 (warm summer), and the differences in the growth and yields of rice plants were distinct in 1957.
2) The growth of rice plants were divided into 3 types, according to the climatic conditions; seaside type, inland type and highland type.
3) In Aomori Prefecture the north-easterlies, named “Yamase-winds”, prevail in summer commonly. In 1958 the “Yamase-winds” were not prevailed, and high temperatures were prevailed in summer. However, the growth of rice plants in seaside region was inferior than inland region. In highland region, the yields were more decreased than previous year, owing to the low temperature in autumn.View full abstractDownload PDF (1004K) -
Y. YAMAKAWA1960 Volume 16 Issue 3 Pages 106-110
Published: December 30, 1960
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSThese observations were carried out in order to clarify the actual situation of the various temperatures (air, water and soil) in paddy field and to determine the effect of carbon black powder on the temperatures of water and soil, and on the growth of paddy plant, at Bukit Merah Paddy Experimental Station in Northern Malaya. The carbon black powder was dusted on the surface of water in paddy field to decrease the water and soil temperatures by intercepting the penetration of solar radiation into water. Results obtained are as follows:
1. The water and soil temperatures varied according to the growth of paddy plant, but the air temperature at a height of 80cm from soil surface did not seem to be affected by paddy growth. The effect of paddy growth on the water and soil temperatures was negligible up to about two weeks before maximum tillering time, and these temperatures were similar to those before transplanting. Soon after passing that time, the effect of shading of leaves and stems of paddy plants on those temperatures was seen and those temperatures began to decrease gradually, reaching minimum temperatures approximately during heading time and increasing steadily towards harvesting time. Furthermore, the results obtained clearly indicated that the temperatures of water and soil were higher than the optimum temperature on the assumption that the optimum soil temperature for paddy plant is about 27°C, during the growth duration and particularly during the vegetative growth period.
2, The temperatures in carbon black powder plot decreased in both water and soil as compared with control plot, particularly during the period from transplanting to heading. Furthermore, there was no sign of weeds growing in carbon black powder plot. Consequently the growth of plants in carbon black powder plot was excellent as compared with control plot and the yield of grain increased by 24% in comparison.View full abstractDownload PDF (679K) -
J. HANYU, K. ONO1960 Volume 16 Issue 3 Pages 111-118
Published: December 30, 1960
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSThis paper deals with the results of measurement of evapotranspiration from the paddy fieild at Kuroishi City situated in the cooler region of Japan, from 1953 to 1956.
The amounts of transpiration were below 1mm/day in the early growth stage of rice plants and increased gradually with their growth (Fig. 1). But, the amount of evaporation decreased with their growth (Fig. 6).
The evapo-transpiration rates to the evaporation E obtained from the meteorological observation field lay within about 1.0-1.3 in the early growth stage and increased after the young ear formation stage. But the rates decreased again from about the tenth day after heading (Fig. 7).
Two peaks of the transpiration rates to E were found after the young ear formation stage and the heading stage. From the index of growth amount ln (l and n mean respectively the plant length and the number of stems per unit area), the transpiration rate t/E (t means the amounts of transpiration) and the seasonal changes of τ(τ means t/E/ln×104), it was presumed that two peaks for t/E during irrigation period would probably be found for the case of ln.
Total evapo-transpiration amounts throughout the irrigation period varied annualy from 440mm to 553mm and were 493mm on the average, showing 1.22 times as much as E. The average transpiration amount was found to be 0.45 times as much as the evapo-transpiration. The annual changes for the average transpiration amount were larger than the cases of the evaporation amounts obtained from the paddy field.View full abstractDownload PDF (1077K) -
Part 4. Drought DamagesM. KUSAKABE1960 Volume 16 Issue 3 Pages 119-120
Published: December 30, 1960
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSDownload PDF (272K) -
[in Japanese]1960 Volume 16 Issue 3 Pages 121-126
Published: December 30, 1960
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSDownload PDF (2934K)
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