北海道平野部のうち6地域の卓越風向および風速の分布を偏形樹調査によって明らかにした.1973～74年にかけて十勝平野,サロベツ原野およびサロマ湖周辺地域を調査し,先に発表した石狩平野,斜網地域,根釧原野の調査資料も加えて考察した.
十勝平野では,約140地点のカラマツの偏形樹を調査した結果,5つの風系すなわち狩勝峠から吹き出す西よりの風は (1) 石狩山地に沿って南西風として吹き上がるもの, (2) 十勝平野を西風として吹き抜けるもの, (3) 芽室付近から向きを変えて北あるいは北西風として吹いているものと,太平洋からの南東風が, (4) 十勝川の河川低地に沿って吹き上がるもの, (5) 日高山脈に沿って南風として吹き上がるもの,とに区分できた.なお, (1) の風道では風下波動の影響と思われる強風域が10～15kmの間隔で分布する.サロベツ原野では,約70地点について調査した.そこでは日本海からの西よりの風は, (1) 西風として吹いているもの, (2) 局地的な地形の影響によって南西風に変化しているもの, (3) 天塩川に沿う河川低地に沿って北西風に変化するもの,の3つの風系に分類できる.
さらに,平均風速と偏形度との関係は,W_sp(m/s)=1.1+1.19G_splで表わされる.ここでW_spは,春(3・4・5月)の農業気象観測所の平均風速(m/S)であり, G_sp1はカラマツの偏形度である.また夏季においては,W_s(m/s)=0.86+1.07G_sfaとなる。同様にして付字sは夏季(5～9月)を示し,G_sfaは石狩平野とサロベツ原野におけるヤチダモ・ハンノキの偏形度である。根釧原野における夏の平均風速とカラマツの偏形度:との関係式(大和田,1973)と,前記2式から,6地域における平均風速の分布図を作成した.平均風速4.0～5.0m/sの強風域は, (1) 石狩平野においては石狩川河口, (2) 斜網地域においては南側山地およびオホーツク海岸沿いの地域, (3) サロマ湖湖岸の周辺, (4) 根釧原野においては尻羽岬・浜中湾および昆布森の周辺, (5) 十勝平野においては新得町の周辺および瓜幕付近,および (6) サロベツ原野においては日本海に沿って約5～10kmの海岸地域,にみられる.一方,弱風域は,根釧原野の中央部,十勝平野における日高山脈に沿う風陰地域および石狩平野における札幌市の周辺地域に見出された.

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ユーゴスラヴィアの石灰岩地域のそれぞれ気候条件・現植生の異なる内陸地方,イストリア半島,アドリア海岸の48地点の試料をもとに,地中海性赤色土の特性の比較を行なった.
湿潤示数Imと塩基飽和度V(%)との間に負の相関が得られた.Fe₂O₃(%)は水分不足量dと高い相関があり, P/E, Imと弱い相関がある.このV(%)とFe₂O₃(%)の関係をみると負の有意の相関が得られるが,両者の関係式の係数と常数は内陸におけるものと,イストリア半島とアドリア海岸におけるものとは異なっている.dとのみ相関を有する色相と,Fe₂O₃(%)との関係をみると,正の相関が得られ,この場合は,内陸とイストリア半島における関係式の係数と常数はアドリア海岸におけるそれと異なっている.ヘマタイトはP/E, Imと高い相関があり,dと弱い相関があるが,ヘマタイトと色相,Fe₂O₃(%)との関係においては,Fe₂O₃(%)が多く,かつヘマタイトのピークが大なときに赤色の度合が増す.MnO(%)はPIE, Im, dのいずれとも相関はない.しかし,MnO(%)と色相,Fe₂O₃(%)との関係においては,MnO(%)が一定量を越えて増大するとFe₂O₃(%)が多くても赤色の度合が減ずる.この関係においては,内陸とイストリア半島の試料による傾向曲線はアドリア海岸の試料による傾向曲線と異なる.
赤色の度合に関与している要素について,現在の気候に支配される度合が弱いか,または全く支配されない要素が加わったとき,イストリア半島が内陸地方と同一の地域的特性をもつ.これは第四紀の氷期において,イストリア半島が内陸地方に非常に近い湿潤な状態にあったためと考えられる.

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The South Daito Island is a remote island 370 kilometers to the east of the main island of Okinawa, and its economy is dependent upon sugarcane monoculture. Since 1967, sea-sonal laborers from foreign countries have been employed to harvest sugarcane on the island. After World War II, seasonal laborers were recruited from Okinawa Island during the harvesting seasons. As it became difficult to recruit laborers from the main island due to the increase of employment opportunities in the main island, laborers were recruited from remote islands of low wages, especially the Miyako Islands.
Since 1964, the low price of sugarcane and the increases of wages in other sectors of the economy in the Ryukyu islands and Japan proper negatively affected the sugarcane cultivation of South Daito Island (Fig. 4). As the island suffered a population decrease, the use of labor in the cultivation became less intensive. The increasing difficulty in the recruitment of laborers even from the Miyako Island aggravated the problem. Finally in 1967 low-wage laborers were introduced from Taiwan, and their number increased rapidly to the point that they became indispensable to the sugar industry of the island (Fig. 7). Thus the outflow of the islanders and the seasonal inflows of foreign laborers presented a strange paradox.
The severance of diplomatic relation between Japan and Taiwan concomitant with the restoration of diplomatic relation between Japan and the People's Republic of China in 1972 prevented the recruitment of the Taiwanese. In the 1972-73 harvesting season, sugarcane had to be harvested without the help of foreigners, which was a great shock to the island community. In the 1973-74 season Koreans were recruited for the harvest, and since then they have come to South Daito Island every year.
It may be safely said that the easy going resort to the low-wage laborers from Taiwan retarded the mechanization of sugarcane agriculture, and caused the shock in 1972. On the other hand, it is also true that the very shock led to the mechanization. In fact, South Daito Island is now one of the areas in Japan that have made good use of machines in agriculture. But hand-reaping of sugarcane is still widely practiced, and a large part of it is carried out by the Koreans. With the abrogation in 1977 of the Okinawa Prefecture Reversion Act of 1972, whereby the seasonal employment of the Koreans in the prefecture is permited, it is impossible to secure foreign laborers in the following seasons. Can the farmers introduce more machines on an economically sound basis? Response of the sugar industry of South Daito Island to this pressing problem remains to be seen.

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It has been said that the feature of longitudinal profile of divides are dependent on different rates of erosion controlled by the difference of geological structures i.e.: density of faults and joint fractures, and lithological differences.
In this paper, the author has tried to make clear the relationship between the structures and the feature of longitudinal profile of high-standing divides located in the Shirouma Range (2, 300_??_2, 933m), Central Honshu, Japan.
He examined the influence of geological structures on the divide form, by measuring the joint density and by making detailed geological maps. The joint density is represented by the number of joints intersecting the circular line of 1m-long on unweathered bedrocks. The joint density was measured at about 300 locations. The relationships between the joint bensity and variations of longitudinal profiles of the divides for different areas are graphically shown in Fig. 2 and Fig. 3, and Table 1 lists them numerically along with sites and lithologies.
The altitude of divides becomes lower with the increase of joint density when the intervals between neighbouring locations are 1m to 2m, as illustrated in Figs. 2-a_??_e. The same relationshipalso exists for measuring-interval of 4m to 20m as shown in Figs. 2-f_??_h. Such relationship cannot be recognized, however, when the intervals are increased to 30m to 112m, as shown Figs. 2-i_??_k, Figs. 3-I and II.
From these examinations, it can be concluded that the small-scale undulation of the longitudinal divide form with horizontal distances of shorter than 20m are strengly controlled by the difference of the joint density, but the large-scale undulation with horizontal distances of longer than 20m seems to be dependent not on the joint density but on the other geological structures.

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