Along the southern coast of the Boso Peninsula, located about 80km south of Tokyo, have developed Holocene coastal terraces, which were elucidated to have been uplifted by tectonic movements associated with major earthquakes (Sugimura & Naruse, 1954; Matsuda et al., 1974). Some of these coastal terraces are composed of marine sediments, about 20m thick, whose facies changes reflect the fluctuation of sea-level relative to the land. The author has investigated these terraces to clarify the role of tectonic movements and eustatic changes of sea-level on their geomorphic development in the Holocene.
The coastal terraces on the southeast coast of the Boso Peninsula can be divided into four surfaces by sharp cliffs, and have been named the Okaseda, the Teraniwa, the Hedate and the Setohama surfaces in the descending order of elevation. The Okaseda surface is distributed fragmentarily along the open coast; however, is widely found along the present river valleys as depositional surfaces of the Okaseda bed of the Holocene marine origin. The Okaseda bed is composed chiefly of bluish silt and fine sand which were deposited under the post-Glacial world-wide transgression. However, such changes in facies of this bed as alternations of silt, gravel and peat, intercalated in the lower Okaseda bed of bluish silt deposited about 9, 000 y. B. P., reflect minor oscillations of sea-level relative to the land, which can be interpreted to have been caused by mionr seismo-tectonic uplifts superposing on the eustatic rise of sea-level in the early Holocene. The Okaseda surface composed of the upper Okaseda bed of fine sand was formed at the time of the maximum rise of sea-level about 6, 000 y. B. P. The terrace surface is a flight of terracettes separated by minor scarps of 1 to 2m high, which is inferred to have been formed by a eustatic lowering succeeding to the maximum rise of sea-level and intermittent seismo-tectonic uplifts superposing on it.
The Teraniwa surface develops continuously everywhere. Along the present river courses, the Teraniwa bed is composed mainly of marine sediments deposited in shallow valleys cutting the Okaseda bed, which indicates the submergence in this ares. Granting that this coast has been always uplifted by tectonic movements, the bed is inferred to have been deposited during a minor eustatic rise of sea-level.
The Hedate surface is composed mainly of thin fluvial sand and gravel, and the Setohama surface is of erosional origin.
The geomorphic history of this coast during the Holocene can be summarised as follows:
(1) Since the rate of eustatic rise of sea-level was low about 9, 000 y. B. P., intermittent seismo-tectonic uplifts were reflected on changes in facies of the lower Okaseda bed.
(2) From 8, 000 to 7, 000 y. B. P., valleys were drowned and filled with marine bluish silt, because the rate of eustatic rise of sea-level was rather high.
(3) When sea-level reached to its highest level around 6, 000 y. B. P., the Okaseda surface was formed and the terracettes were developed by intermittent seismotectonic uplifts during the subsequent lowering of sea-level.
(4) About 3, 500 y. B. P., a relative rise of sea-level (a minor eustatic rise of sea-level?) occurred and the Teraniwa bed was deposited in shallow valleys cutting the Okaseda surface. Soon sea-level turned to lower again and the Teraniwa surface emerged.
(5) Since then, sea-level has continuously lowered, and the Hedate and the Setohama surfaces emerged by seismo-tectonic uplift.

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The author considers that there should be a purpose for each regionalization of agricul-ture. From this viewpoint, he attempted an agricultural regionalization of Japan employing indices of farm-income changes as its data. The intended regionalization was achieved through three-step regionalization of 305 districts of Japan.
The 305 districts were classified on the basis of the rate of increase of farm income from 1960 to 1974 into three categories, high growth districts, medium growth districts and low growth districts (see the key for Fig. 2). The first-step regionalization, which produced 11 regions (Fig. 2), was based on the above classification of the districts and the spatial contiguity of the districts. For the second-step regionalization, an index of change in the crop combination of a district in terms of incomes from the crops was developed. On the basis of this index and the spatial contiguity of the districts, the 11 regions were divided into 23 subregions (Fig. 3).
For 1960 and 1974, the 305 districts were classified into four crop combination types: grains and potatoes, primarily grains and potatoes with commercial crops, primarily commercial crops with grains and potatoes, and commercial crops. Each district's shift from one crop combination type to another from 1960 (Fig. 4) to 1974 (Fig. 5) was categorized (Fig. 6). In the third-step regionalization, which was based on the classification of the districts shown in Fig. 6, the 23 subregions were further divided into 33 areas (Fig. 7). The result is an agricultural regionalization from the viewpoint of agricultural changes in Japan, which experienced rapid growth of its economy during the period. In the above regionalization, the agricultural changes were measured by the farm-income growth and the crop combination changes. The author assumed that crop combination reflected qualitative as well as quantitative aspects of farm management.
The unit areas (the 305 districts) used by other researchers were uncritically adopted in this paper, which might have been ill-suited for the purpose of this study. In drawing the regional boundaries, the problem of handling a unhomogeneous district or a few unhomo-geneous districts within a region was a difficult one and remains so. Further investigation of agricultural regionalization based on indices of changes is necessary. Moreover, since the increase of non-farm incomes of farm households is particularly rapid in Japan, agricultural regionalization based on indices of income-changes of farm households, which include non-farm incomes as well as farm incomes, should be studied. It is also desirable to analyze agriculture of small areas in order to understand the process of transformation of agricultural regions.

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In the western part of the Kii Peninsula, the Median Tectonic Line separates the Izumi Range from the Kino-kawa lowland with a conspicuous topographical contrast, forming a great geological boundary between the Upper Cretaceous Izumi group of the Inner Zone and the Paleozoic crystalline schist of the Outer Zone, the latter of which is mostly overlain by the Plio-Pleistocene lacustrine sediments, the late Quaternary terrace gravels, and the Holocene alluvial deposits.
The writers investigated mainly fault features and related faulting along the southern foot of the Izumi Range. The results are briefly summarized as follows.
1) Many distinct evidences of the right-lateral movement are continuously discernible along the active fault system of the Median Tectonic Line in this area.
2) The Negoro fault, the principal fault in the western part of the area surveyed, vertically and horizontally interrupts the several steps of terrace surfaces (dissected fans) and the dissected valleys. Calculated from the known ages of the terrace surface, cliff, and dissected valley etc. across the active faults, which are roughly estimated by the correlation and the dated values such as carbon-14, fission track, and K-Ar methods in the neighboring areas, the mean rates of faulting are 0.9_??_3.1m/10³ years laterally, and 0.11._??_0.40m/10³ years in the vertically northward direction.
3) As the horizontal displacement (D) is in proportion to length (L) of the river upstream from the fault with a certain coefficient of correlation (a), the relation is expressed as D=aL. Calculation gives the coefficient, a=0.38 for the Negoro fault and a=0.22 for the Gomyo-dani fault, the principal one in the eastern half of this area. They implicate that the both are among the most active transcurrent faults in the inland Japan, and that the displacements have been taken place with an almost uniform rate at least during the late Quaternary.
4) The mean slip rates of vertical and horizontal displacements in this area are slightly lower in comparison with those in Shikoku. This may be accounted for by the fact that this area is located at the eastern end of the active fault system of the Median Tectonic Line, and that the displacements are scattered among many other active faults in the Inner Zone of the hinki district.
5) There are some differences in place and mode of displacement among the faults along the Median Tectonic Line int his area. Reverse faulting, which occurred in the first half of the Quaternary along the great geological boundary, formed the general outline of the fault angle depression. On the contrary, right-lateral faulting began from the middle Quaternary as the new fracture within the uppermost Cretaceous Izumi group, and has continued to the present with a mountain-building movement.

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Bunjirô Kotô (1856_??_1935) ist einer der Geologen, die zur Entwicklung der modernen Geographie von Japan beigetragen haben.
An der Universität Tokyo studierte er 1877_??_1879 Geologie. Zu semen Lehrern gehörte der deutsche Geolog E. Naumann. Japanisches Kultusministerium schickte Kotô nach Deutschland, Geologie zu studieren. 1881/82 in Leipzig and 1882_??_1884 in München studierte er Geologie. Im Frühling 1884 kehrte er nach Japan zurück, and 1886_??_1921 hatte er den Lehrstuhl für Geologie an der Kaiserlichen Universität Tokyo inne.
1887 veröffentlichte er eine Buchbesprechung über das zweibändige Japanwerk von J. J. Rein in der Zeitschrift “Tôyô Gakugei Zasshi”, and 1908 schrieb er einen Aufsatz über die “Neue Geistesströmung in den deutschen Geographen” in der Zeitschrift “Rekishichiri”. Seine eingehenden Kenntnisse in der deutschen Geographie zeigen diese Buchbesprechung and der Aufsatz.
Im ersten Band des “Journal of Geography (Chigaku Zasshi)” 1889 erschien emn Aufsatz unter dem sonderbaren Titel “Ich gebe die Definition der Geographie anlässlich der ersten Veröffentlichung des ‘Journal of Geography’”. Seine Definition kommt aus dem ersten Kapitel “Begrif der Geographie” and dem zweiten “Die Stellung der Geographie im Kreise der Wissenschaften” der ersten Abteilung von F. Ratzels “Anthropo-Geographie, I.” (1882). Das zeigt, dass schon am Ende der 80er Jahre des 19. Jh. ein Teil von Ratzels “Anthropo-Geographie, I.” (1882) in Japan vorgestellt wurde, and Kotô die Kenntnisse von nicht nur Physischer Geographie, sondern auch der Geographie des Menschen hatte.
Sowohl Kotô als Ratzel kritisierten, dass die bisherige Geographie nur die Erdbeschreibung gewesen war, and die Natur der Länder fast vernachlässigt worden war. Man kann die Geschichte der japanischen Geographie der Meiji-Zeit nicht verstehen, ohne den Prozess der Einführung der europäischen and amerikanischen Geographie in Japan zu verfolgen. Doch spätestens in der zweiten Hälfte der Meiji-Zeit waren die deutschen Gedanken über, die Geographie unmittelbar von “Anthropo-Geographie, I.” (1882) oder mittelbar durch den Aufsatz Kotôs eingeführt worden, and sie waren die neuesten Gedanken über die Geographie zu jener Zeit.

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