農業気象
Online ISSN : 1881-0136
Print ISSN : 0021-8588
ISSN-L : 0021-8588
18 巻, 3 号
選択された号の論文の11件中1~11を表示しています
  • 柑橘葉温に及ぼす日射量と風速の影響
    武智 修, 長谷場 徹也, 泊 功, 秋元 稔万
    1962 年 18 巻 3 号 p. 89-91
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
    葉温測定法について, 基礎的注意を払つた上で柑橘葉面に平行に層流に近い風をあて, 葉面の受ける短波輻射量と風速との関係において葉温を測定した。
    まず日射量一定で風速を変えた場合, 葉温は風速の増加と共に低下し, この効果は低風速で著しかつた。
    次に風速一定で日射量を変えた場合, 葉温は日射量の増加と共に殆ど直線的に上昇し, その上昇率は低風速の場合ほど顕著であつた。
  • 柑橘葉面の層流熱伝達
    武智 修, 長谷場 徹也
    1962 年 18 巻 3 号 p. 92-97
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
    柑橘の切枝を水挿したものについて, 葉面に平行に層流の風をあて, 日射量, 風速を変化させた場合の葉温と蒸散量の変化を測定した。一方葉面熱収支式を検討し, それから強制対流伝達熱量は他の諸項の残差項として求められ, 熱伝達係数の測定値は風速に関して0.5乗であらわされた。
    このことは層流の風に平行におかれた平板の熱伝達係数が風速の0.5乗であらわされるE. Pohlhausen の理論式とじゆうぶん一致した。
    次に熱伝達係数の測定数値と葉面を隋円面に近似して計算した理論値とを比較し, 葉面に適用すべき層流熱伝達係数としては理論値に1よりやや大きい常数1.25を補正係数として乗ずればよいことを見出した。
  • 1962 年 18 巻 3 号 p. 97
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
  • 〔第1報〕
    鈴木 義則
    1962 年 18 巻 3 号 p. 98-104
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
    The effect of a temperature gradient on the movement and distribution of soil moisture has been examined in closed column of soil for various initial water contents (1%-7%).
    The results are as follows:
    1) In all except the driest and wettest columns of soil there was a transfer of moisture towards the colder end from the waremr, that is, water evaporating from the hotter soil moves as vapor into colder soil, where it condenses and return as liquid when a favorable gradient of moisture has been established.
    2) For the transfer of soil moisture, liquid flow works as a control factor and reduces the amount of net transfer due to temprature gradient.
    3) The amount of a transfer of soil moisture varies with the initial water content, and for the sand (it's particle 0.175-0.5mm) the maximum transfer of moisture from the hot to the cold end occurred between 3.5% and 4.0% of the initial water content which is approximately one third of the moisture equivalent.
    4) The observed net transfer of moisture coincides with the vapor flows calculated by the diffsion equation of Penman, Krischer & Rohnalter, and others quite well at the maximum transfer of moisture, but, no good in other ranges of initial water content.
  • 農業気候に関する研究 第6報
    羽生 寿郎
    1962 年 18 巻 3 号 p. 105-108
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
    In order to analyse the relationship of air temperature to the growth of crops, the classificatory constitution of air temperature during the growth stages of crops should be clarified. But the assumption of such classification from the recording paper is troublesome and collection of recording papers from various places is difficult. From these reasons, the writer tried to obtain the classificatory constitution by calculation through the typification of diurnal variations of air temperature.
    Assuming that θmin shows minimum air temperature and that R represents diurnal range of air temperature, θt showing air temperature at the time of t becomes as follows:
    θtmin+atR (1)
    where at is the coefficient of diurnal range of air temperature. Through the same procedure, θ0 showing mean daily air temperature follows as
    θ0min+aDR (2)
    where aD shows the average of at.
    The average air temperature θm otained from the daily maximum and the minimum is as follows:
    θmmin+0.50R (3)
    From formulas (2) and (3) aD is obtained:
    aD=0.50-Δθ/R (4)
    where Δθ=θm0.
    The monthly average values of aD calculated from (4) by use of the data from the main stations in Japan are shown in Fig. 1.
    The distribution of annual variation of aD classified as A1, A2, B and C types is shown in Fig. 3. The average aD ranging from May to August becomes 0.45 in Japan (Fig. 3). By drawing both diurnal variation curves of air temperatures having various aD values (Fig. 4) and the curve (C-curve) put the case that the emergence times of the maximum and the minimum points on a sine-curve are distorted as 5a.m. and 2p.m., Δt showing the difference of emergible time more than constant at obtaind from both diurnal variation curve of air temperature having certain aD value and C-curve was obtained (Fig. 5). Δt was ascertained to be -1.3 hours in the case of aD=0.45 and at=0.1-0.9. As the emergible time of C-curve at the case of more thanconstant at value is equal to the case of sine-curve, it is probable to obtain the emergible time by the calculation and the curve for aD=0.45 can be obtained by adjusting Δt, -1.3 hours (Fig. 7, S-curve). An example for the diurnal variation S-curve of air temperature was shown in Fig. 4 (full line). Such S-curve will be taken as a typical diurnal variation curve of air temperature during summer season in Japan. By using S-curve, the emergible times of classificatory air temperatures will be easily obtained from Fig. 6, when the air temperature is substituted by at in a formula (1).
  • 第1報 水稲の出穂期と気温との関係 (1)
    羽生 寿郎, 内島 立郎
    1962 年 18 巻 3 号 p. 109-117
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
    水稲の生育と気象との関連性の究明は栽培に計画性を持たせ, あるいは栽培技術の確立ないしは改善の方向を予見するために必要なことである。生育を量と位相に区別し, 位相生長として出穂を起す生長速度を取上げ, 気温との関係を青森農試本場及び藤坂試験地の豊凶考照試験のデータについて解析し次の結果を得た。
    1) 前に求めた気温日変化の模型から, 計算により階層別気温の出現時間と積算気温を求め, その結果から品種ごとの有効気温係数αを求めた。
    2) αと気温θとの積としての生長気温当量θ*を求め, 移植~出穂期間のθ*の和を有効積算気温Σt(h)i=0θi*と名付け, これが品種によりほぼ一定の値を持つことを示した。このことは出穂を起す生長速度が気温の函数として表わしうることを意味する。
    3) 以上の結果を用い, 気温から出穂期を推定する方法を見いだした。
    4) 土壌・肥料・栽培条件及び気温以外の気象要素も一種の温度係数βiとして, 函数に導入しうることを提唱した。
  • 谷 信輝
    1962 年 18 巻 3 号 p. 118-121
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
    From the records of wind speed and direction at Miyakonojo Weather Station in last ten years, some characters of strong wind are obtained.
    Maximum mean wind speed over 10m/s is seen in about 50 days during a year, and about a half of these days appers in winter season.
    In winter season (December, January February, and March) seasonal wind blows very frequently, their directions are almost W, WNW, NW, and maximum wind speed does not over 20m/s. In summer season (June, Juy, August, and September) mild wind generally blows except when typhoon comes. There are two directions that very strong wind blow out, one is NNE, NE and the other is SE-S-SW, and their speeds some times beyond 30m/s, huge dameges are occured. These facts suggest that wind breaks for prevention of wind damage occured in both winter and summer seasons need two directions.
    It is considered that one or two typhoons come to this district every year and the typhoon that the maximum wind speed is about 15m/s comes almost every year, maximum wind speed over 25, 35m/s occure onece per 3-4 years and 20 years.
    The duration time of strong wind by typhoon is obtained from 16 typhoons. The time while the wind blows continuously over 10, 15, 20m/s are about 24, 10, and 5 hours respectively.
  • 日下部 正雄
    1962 年 18 巻 3 号 p. 122-124
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
  • 中村 千里, 小林 一雄
    1962 年 18 巻 3 号 p. 125-127
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
  • 井上 栄一
    1962 年 18 巻 3 号 p. 128-129
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
  • 日下部 正雄
    1962 年 18 巻 3 号 p. 130-131
    発行日: 1962/12/25
    公開日: 2010/02/25
    ジャーナル フリー
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