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Volume 11, Issue 3
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R. YAKUWA1955 Volume 11 Issue 3 Pages 81-83
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSIn this experiment the effect of solar radiation upon the melting of frozen soil was studied.
(1) The observations were made at Taisho village, Tokachi district Hokkaido, from 14 to 16 April 1951.
The arrangement of plots is as follows:
Plot 1. Control. On the surface of frozen soil, there was a snow layer of 30cm thick.
Plot 2. Bare soil. There was no snow on the soil surface and it fully received the solar radiation.
Each plot is 3.0×3.0m2 in area.
(2) Hourly variations of soil temperatures in plot 3 are shown in Figure 1.
The soil temperature in plot 1 showed no remarkable change during the observation because the snow layer on the surface prevented the penetration of solar radiation to the surface.
The thickness of frozen layer in Plot 1 was nearly constant during the observation while the frozen layer in plot 2 gradually became thin (See Table 1).
The amount of melting of frozen layer in plot 1 from 10h00m to 16h45m, 15 April was 4.1cm.
(3) The amounts of heat which flow in through a plane x1 and flow out through a plane x4 for the time interval from t1 to t2 will be called Q1 and Q2 respectively.
The surplus Q1-Q2=W0, which the layer from x1 to x5 receives, is used for melting of the frozen layer and raising the temperatures of layers X1, H2, H3 and X4.
Suppose that the thickness of the layer which is melted, is h3-h2, then the amount of heat, L, used for melting is 80 (h3-h2)pw where pw is moisture content of the frozen soil by volume.
To calculate the amount of heat used for raising of temperature of layer X1 for the time interval from t1 to t2, consider a vertical column of unit sectional area in the layer reaching from x1 to h2.
Let u1·1 and u1·2 be the temperatures of the infinitesmal element dx in the column corresponding to the times t1 and t2, then the variation of heat content of the soil column X1 is
∫x0+X1/2x0-X1/2c2(u1·2-u1·1)dx
where c2 is the heat capacity of the soil.
In like manner the variation of heat content of the soil in the layer X4 is
∫x0+X4/2x0X4/2c4(u4·2-u4·1)dx
Let us consider the condition that the temperatures of layers H2 and H3 at t1 and t2 are the same. In this case we have the equation (5).
From equations (3), (4), and (5) we have equation (6).
By means of formula (7) and the observed values of soil temperatures, the amount of melting of the frozen soil has been computed for 3 periods. The results obtained are shown in Table 2.View full abstractDownload PDF (388K) -
1955 Volume 11 Issue 3 Pages 83-86
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSDownload PDF (566K) -
I. IIZUKA1955 Volume 11 Issue 3 Pages 84-86
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSCarbon dioxid concentration in the peach orchard was microclimaticlly measured. For the parpus of this measuring a Haldane gas analyser was used.
Diurnal variation of carbon dioxide in the orchard:-
This gas concentration was lower in the daytime than in the night-time and it increased rapidly after sunset. It is probable that this phenomenon was caused by more vigoron carbon assimilation than respiration in the daytime and by the fact that at night the former ceased and only the latter was carried out, and that more of this gas was released from the soil in the night-time than in the daytime.
Distribution of carbon dioxide in the orchard:-
Since it scarecely blows at night, the atmosphere where leaves were thicker and nearer to the ground surface contained more of this gas than at other parts in the orchard. In the early morning, the gas began to decrease gradually from part of the tree where sun fell. This phenomenon extended towards shady part of the tree as the sun rose high. And constant tendency was recognized during daytime when wind blew.View full abstractDownload PDF (365K) -
Part 2. Spectra of Waving Plants and Plants VibrationE. INOUE1955 Volume 11 Issue 3 Pages 87-90
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSPhenomena of waving plants and vibration of individual plant are regarded to be both caused by behaviors of turbulons contained in the surface wind just at the plants height. Turbulons are divided into two classes of the coupling frictictional ones and the larger ones. The former is further subdivided into the predominant corresponding to the earlier mixing length concept, the intermediate to which the well known second similarity hypothesis of turbulence is applicable and the smallest to which the first similarity hypothesis is applicable.
The predominant turbulon is fed energy from the shearing mean wind field and simultaneously provides the same amount of energy to the intermediate, and the energy distribution among the intermediate turbulons is represented by the so-called -5/3 power law of the turbulon energy spectra.
The Lagrangian description of turbulon spectrum is applied to the waving plants phenomena, in which the progressing plants waving is compared to the non-lift balloons floating over the plants, and the Lagrangian spectrum of turbulence is presented as
F(n/n0)=2/π1/1+(n+n0)2,
where n denotes the life-frequency of turbulon and n0 does approximately that of the predominant turbulon and/or waving plants. The life-time of the predominant waving plants over rice fields is estimated to decrease with increasing wind velocity and to attain a constant value of about 1.5sec at and beyond the critical wind velocity (over ca. 5.5m/sec at 2m height).
The vibration of individual plants is regarded to be due to the successive passage of turbulons in the surface wind. Since under a condition of wind velocity below the critical the fluctuations in displacement (or the amplitude of plant vibration) is represented in terms of the wind force or wind pressure fluctuations, the spectral function of wind pressure fluctuations is suggested to be applicable to the plants vibration as follows:
F(N/N0)=20/9(N/N0)3/{1+(N/N0)2}8/6,
where N0 corresponds approximately to the passage-frequency of the predominant turbulon.
The plants vibration is divided also into the predominant, the intermediate and the smallest vibration. The smallest vibration is considered to be caused by turbulons of the passage-time just same as the period of natural vibration of plants. At and beyond the critical wind velocity, periods of the predominant and of the smallest vibration coincide with each other and the above spectral function cannot be applied, but the line spectrum of vibration is expected to predominate at the period of natural vibration of plants.
No practical observations have yet been available to be compared to the theoretical results.View full abstractDownload PDF (600K) -
On the height and effective area of the shelter-hedgesS. TANAKA, T. TANIZAWA, S. SANO, S. KAKINUMA, S. KODERA1955 Volume 11 Issue 3 Pages 91-94
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSConcerning the relation between the height of shelter-hedges and the effective area, the past researchers have put forth two different results. Namely, the one is that the higher the hedge the wider is the effective area and the other is the contrary. Theoretically speaking, the area is to be wider in proportion to the 8/7 power of H. (H is the height) The following factors may be suggested to explain how the different conclusions have been reached.
1) The direction of the wind; The fence placed at right angles to the wind direction produces a remarkably different effective area from the fence placed at oblique angles.
2) Turbulence; The more turbulence of the wind causes the less wide effective area; Near the seashore, owing to little turbulence in general, the effective area becomes wider, while in the inland place with woods and forests the area becomes narrower.
3) The roughness on the surface of the ground; Much unevenness or undulation on the surface of the earth or much grassiness lessens the effective area.
4) The structure of the shelter-hedge; The density, breadth, position of the branches, flexibility of the crown, and so on exert a great influence on the effective area,
5) The velocity of the wind; The higher velocity causes the more turbulence, and in consequence the effective area becomes less. On the contrary, the lower velocity causes the area to be wider. However, the experiments have brought about a result to the contrary.
The result of the experiment:
1) Conditions
Two kinds of fences: 100cm. and 50cm. in height.
The kind of fence employed: board-fence, 75% covered.
The direction of the wind: right angles to the fence (variance of about 5 degrees to be included)
The velocity of the wind: 6-8m/sec. Places of measurement: Three places of different turbulences.
Measuring apparatus: small type of Robinson's anemometer.
2) Result
The more the turbulence the less has been the difference in ratios of the wind velocity of the two fences. The difference is to be shown in a stright line in its diagram. In the case of the 50cm high one, the difference deviates from the stright linear formula. Times the height of the hedges, in both kinds, which decrease the velocity of the wind 50%, becomes the more where the turbulence is less. In the case of the fence 100cm high, the ratio of the increase of the effective area is shown as H1.03-H1.09 (H denotes times the height of the hedge) -H1.06 as average. Now it has become clear that when the fences get higher, the effective area grow more in proportion to times of the height of the fences.View full abstractDownload PDF (561K) -
H. NISHIUCHI1955 Volume 11 Issue 3 Pages 95-96
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSIt has been said that northern section of the Haruki river-side being close by Beppu city had been suffering considerably the damages by blast and rice stem's borers than the southern section. The comparative microclimatic observations of tempeatures of air and soil were made at the both fields on Jan. 3 and 4, 1945.
As the result of these observations, it was confirmed that the southern fields of the river-side showed higher soil temperatures than the northern ones. It was the writer's understanding that the more damage of paddy's culture in summer at the latter did not seem to due to favorable hibernation of Piricularia or larvae of rice stem's borers and the less damage at the former seemed to be caused by more resistance of the paddy plant to the disease and insect damages owing to the good growth of paddy by the higher soil temperature condition in summer.View full abstractDownload PDF (301K) -
The function of the multiple shelter-hedgeS. TANAKA, T. TANIZAWA, H. SANO, S. KAKINUMA1955 Volume 11 Issue 3 Pages 97-99
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSAs was seen in our previous report, a lot of turbulence in the wind reduces the function of the shelter-hedge. Moreover, some experiments in the wind tunnel clearly show that the multiple shelter-hedge is more affected by the turbulence than the single shelter-hedge.
By our experiments the multiple shelter-hedge of two belts has a higher ratio of wind velocity than the single one by 4 to 8%, as far as 20 times the height of the hedge, on the leeward; the 3-belted one has an increase of 1 to 4% in ratio of wind velocity, as compared with the 2-belted one, the 4-belted one has an increase of 1 to 2% in the ratio, as far as 10 times the height of the hedge, on the leeward, as compared with the 3-belted one. However, within the distance of 10 times the height of the hedge, clear result has not been obtained.
Concerning the vertical distribution of wind velocity, in the single hedge remain the spheres of the turbulence of 120cm, 80cm, and 50cm, respectively at the distance of 5, 10 and 15 times the height of the hedge, on the leeward, while in the multiple hedges the spheres of 100cm, 50cm, 30cm, remain, at the distance of 5, 10, and 15 times, respectively, on the leeward.
As for the turbulence of wind velocity, the 2-belted hedge has an increase of 2% over the single one, at the distance of 15, 20, 25 times the height to the leeward. But the turbulence caused by the multiple hedge seems to be constant when the belts increase in number.View full abstractDownload PDF (460K) -
SHIGEKI KOBAYASHI1955 Volume 11 Issue 3 Pages 100-102
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSThe area in consideration comprises 885 neatly arranged but almost about tennis court dimensioned paddy fields, several gentle brooks, numerous straight foot-paths and cart-roads together with about a dozen of lotus marshes in a region of 1.5km×0.6km in the Delta Plain south of Lake Suwa.
In the autumn of 1935 the writer investigated the variety of the rice crop cutlivated at each field, which he entered, in a map of 1:7000. The numerous tiny hatched tetrahedrons were the paddy fields where the variety styled “Aikoku No, 20”—strong, manure-resistant and pest-resistant—were cultivated, the scattering black patterns were the lotus marshs and the rectangles without any hatching were mostly planted with the variety styled “Sekitori” (in Jap.) which yields good qualified rice but are weak against the attack of pest.
In order to scrutinize the general tendency of the distribution, he twice dealt with Fig. 1 after Katsue Misawa's method, the result of which is shown in Fig. 2. The Arabic numerals in the figure indicate the average percentage of the rice fields planted with “Aikoku No. 20” with an unit of 10 percent. Although the appearance of this objective region is completely flat, there exist, however, slight differences in elevation. The areas where the “Aikoku No. 20” were prevelent—the centers of which were located at the northeast and the north-west sectors of Fig. 2—coinsides with the lowest therefore, sometimes water-stagnant fields which were formerly irrigated with nitrogen-rich water from many wells excavated there. This fact indicate that the variety of the crop is some-times of good service in revealing the regional characteristics of a given area.View full abstractDownload PDF (2256K) -
I. ABE, S. TAKAHASHI1955 Volume 11 Issue 3 Pages 103-106
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSThe experiments were carried out to make clear the microclimate and the growth of soy-beans, interplanting in the potato fields.
The results obtained were as follows:
1) The yields of main crop (potato) was not so decreased by interplanting soy-beans, and the total yields of both crops were much increased as compared with main crop only.
2) It seemed that the micro-climate formed by interplanting was less affected to the growth of the main crop.
3) In the former stage of the growth, environmental conditions were mere unfavorable to the interplanting soy-beans that the single planting one. On the contrary, in the later stage, they were rather favorable to the interplanting one. Therefore, the yield her individual plant was superior in the interplanting soy-beans.
4) The insect injury (by Grapholitha glycinivorella) was less in the interplanting soy-beans. It was considered that one of this reason was due to the differences of microclimate.View full abstractDownload PDF (722K) -
H. MISAWA1955 Volume 11 Issue 3 Pages 107-108
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
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R. Yakuwa, M. Isii1955 Volume 11 Issue 3 Pages 109-110
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
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M. SHIRAKI, K. SUZUKI, M. YAMADA1955 Volume 11 Issue 3 Pages 111-112
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
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K. KOMIYA1955 Volume 11 Issue 3 Pages 113-114
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSDownload PDF (314K) -
K. NODA, S. TATEISHI1955 Volume 11 Issue 3 Pages 115
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSDownload PDF (183K) -
[in Japanese]1955 Volume 11 Issue 3 Pages 116-118
Published: December 30, 1955
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSDownload PDF (524K)
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