地理学評論
Online ISSN : 2185-1719
Print ISSN : 0016-7444
ISSN-L : 0016-7444
27 巻, 9 号
選択された号の論文の5件中1~5を表示しています
  • 防災都市計画の基礎として
    上田 一人
    1954 年 27 巻 9 号 p. 355-365
    発行日: 1954/09/01
    公開日: 2008/12/24
    ジャーナル フリー
    Landslides have become one of the most important matters of concern because of the physical characteristics of our country and the frequent occurrence of landslide in recent years. The studies of landslides have not been fully made because of their momentary nature of occurrence. Kobe and Kure Cities suffered from great disasters of this kind not only once but twice during the last 15 years. On 28 of June, 1953, in the northernmost peninsular part of Kyusyu including Moji City, there took place 619 landslides and countless slides of a small scale, which killed 137 persons, injured 477 persons and damaged 2533 houses. The writer made an investigation of these landslides. The writer subdivided the areas affected into three zones: the zone of surface breaking, the. intermediate zone of motion, and the zone of deposition. However, since the zone of surface breaking was the basic zone from the standpoint of prevention of disasters, be has concentrated his study on that zone. The principal facts revealed by the the writer are as follows:
    (1) The gradient of slope where the landslides occurred most numerously is 30° to 35°, although the genesis of a landslide depends upon not only the gradient but the amount of rainfall, the angle of repose of the surface soil, and the change of gradient in the slope, etc. The gradient for maximum occurrence of landslides in the area studied around Moji is lower than that observed in Kobe area. (Fig. 1)
    (2) The dimension of the zone of surface breaking, is not so large as in the cases preveously reported. It is liable to be overestimated owing to the fact that the out-wash debris often covers an extensive area. The type and scale of the landslides in the Schalstein regions of the area (i. e. the Kazashi Mountainland) are similar to those in the Granite region along the River Watarase in Northern Kanto reported by Mr. Ichikawa. They are of a wide and deep type (not of a long and shallow type), but are more or less different from those in the Palaeozoic region (i. e. the Tonoue Mountainland) of the area studied. (Fig. 2).
    (3) As it is of a wide and deep, type, the quantity of the debris is commonly large, being 1500-2000m3 in cases of landslides from slope of 30°-35°. In cases where the gradient is over 35°, its quantity is less than those above-described. (Fig. 4).
    (4) If the vegetation is taken into consideration, it can be said that landslides occurred most numerously in the area covered with Japanese reed-grass. Dwarf deciduous tree cover seems to have little resistance against slides. That there is an extensive area under Japanese reed-grass is regarded as an important factor in the multiple occurrence of landslides. On the other hand, the quantity of the debris which slides decreases as the age of the forest trees and their density increases.
    5) The density of surface breaking is in proportion to the altitude in the respective regions. The density is especially high in the north-eastern hills chiefly composed of shale, schalstein, sandstone, and in the Kazashi Mountainland chiefly made up of schalstein, diorite, clayslate. It is lower in the Tonoue Mountainland composed of Palaoezoic rocks.
  • 樗木 昇一
    1954 年 27 巻 9 号 p. 366-373
    発行日: 1954/09/01
    公開日: 2008/12/24
    ジャーナル フリー
    From the viewpoint of the rice cropping season in Japan, Kyushu is usually classified as a district of the warm and late type. But the author's study revealed that there is about two months' difference in the beginning of the rice cropping season even in Kyushu itself a difference equivalent to that found between the northern and the southern ends of Japan. Detailed examination of the rice cropping season in Kyushu carried on by card method made clear that Kyushu is devided into the following four areas according to the type of their rice cropping season.
    Ist. type area: South-western Islands containing Yakushima and Tanegashima. The area of the earliest type in Japan. IInd. type area: Medial Kyushu mountains and Seburi mountains in northern Kyushu. The area of the earliest type in Kyushu. Here the rice cropping season begins as early as in Tohoku, Hokuriku and San-in districts. IIIrd. type area: Northwestern coastal area and inland area of southern Kyushu. The typical area in Kyushu. IVth. type area: Southwestern coastal area (islands and coastal belt of the Yatsushiro Sea and coatsal lowlands around the Ariake Bay). The area of the latest type in Kyushu and in Japan.
    Such regional differentiation of the rice cropping season as described above can be considered as the combined resultant of the following four factors, at least. (1) Climate: The air temperature. and the typhoon are the two predominantly influential climatic elements on rice cropping. (2) Irrigation water: Which is most prevailingly used, rainwarer, river or ravine water, irrigation-pond water, creek water, well water, etc.? (3) Relation to the winter crops: This hastens or retards the coming of the rice cropping season. (4) Variety of rice plant: What variety is cultivated? The author has described and discussed about these four factors in this article. A bare mention is made here only of the variety of rice-plant.
    The common varieties in Kyushu as a whole are of high sensibility for sun light, of strong resistance to rice deseases and of grains hard to drop. This corresponds with the fact that Kyushu is the warmest district in Japan and often suffers from damage caused by typhoon. In the areas of the early type (South-western Islands and the mountainous lands), however, the varieties of early maturity or of strong resistance to coolness are cultivated as in Tohoku and Hokuriku districts.
  • 瀬戸内沿海の村落構造と林野荒廃
    千葉 徳爾
    1954 年 27 巻 9 号 p. 374-384
    発行日: 1954/09/01
    公開日: 2008/12/24
    ジャーナル フリー
    The bare hills of the Okayama district have been described in previous article. Similar conditions prevail throughout the Setouchi area. As shown in Fig. 1, for instance, many bare patches are distributed in the Iriaichi where inhabitants of the three villages of Yuge, Seiriki and Futsukaichi gathered grass and brush for fuel and fertilizer. The inhabitants of Futsukaichi, in particular, had no forests of their own, and they had to gather fuel only in, the part of the community-owned forests, allocated to them for such purposes (shown by oblique lines).
    In general the poorer classes of the farming population on the coast of Setouchi had no forest to use in the recent past. But the farmers who lived on the northern plateau and southern mountainous districts had their own-forests, though they were poorer than the inhabitants living in the low lands, for the latter could become merchants and pedlars. Under these circumstances-the poor people in the low land used intensively and excessively the only permitted. woodland area-the Iriaichi. The resultant devastation was most marked in the early past of the Meiji era. (1867-1912).
    The denudedI hillsides today are being covered with trees as the result of the-transference of the community forests to the good management of cities, towns and villages. Regional differences because of this changed management appear in the distribution of bare patches.
    In Fig. 2 and 3, for instance, in Okayama Prefecture in the counties where-there are many bare patches community forests have not been transfered.
    On contrast, in the counties where such transference has been effected there are almost no bare patches. This shows that the arid, climate and weathered granite are not the causes of erosion, but that the mismanagement of community forests in the last few centuries is the main cause of the denuded hills along the coast of Setouchi.
  • 新潟工業地帯を中心として
    佐藤 元重
    1954 年 27 巻 9 号 p. 385-394
    発行日: 1954/09/01
    公開日: 2008/12/24
    ジャーナル フリー
    The organization of a transportation system is much influenced by physical conditions. Once established it is one of the important factors in the develoment of an industrial region. Along with the organization of a transportation system, the role in society of the natural conditions which have been potent factors, even though they remain unchanged, will. come to have new economic aspects.
    This treatise deals with the Niigata industrial region as an example. It shows that no matter how large a population or how great natural resources it may have, if the transportation system is not fully organized, the region does not develop economically. This treatise, laying an emphasis upon. the early stage of the development of modern industry in the Niigata area, shows that the process of the organization of the transportation system depends upon the develepment of producing activities and production techniques. The study is limited to the, Meiji and Taisho periods (1867_??_1926) and not the Showa period (1926_??_) when heavy and chemical industries were extraordinarily developed and.their transportation system was more fully organized. The region dealt with here is Niigata city, the center of the industrial region in the prefecture, and surrounding area.
  • 1954 年 27 巻 9 号 p. 395-404_1
    発行日: 1954/09/01
    公開日: 2008/12/24
    ジャーナル フリー
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