The river plains in this area are divided into the Holocene fluvial terraces and the flood plains. In the northern part of this area, the river plains of the mid- and down-stream of the Aisaka and the Gonohe Rivers are among the uplands, and the width of the river plains deviates a little except at the river mouths. Near the river mouths, there are old meander channels, but only a small number of natural levees are distributed. The natural levees are generally so low and flat as ones near the mouth of the Mabechi River to the south. In the reach about 3 to 5 km from the river mouth, the flood plain is smaller than ones in the upstream and at the river mouth. The width varies a little, and the surface of the terrace is flat, composed of peaty clay and silt. Further, in the reach about 5 to 15 km from the river mouth, the natural levees composed of silt and sand continue on the fluvial terrace, higher than those of the downstream. Larger ones are about 2 m in relative hight above the fluvial terrace. The terra e surface behind the natural levees is more undulated, composed of peaty silt and clay. The flood plain composed of sand and gravel below this fluvial terrace has wider meander belt, and many well-developed old channels.
From the above geomorphological evidences, the processes of the rivers may be concluded as follows.
Just after the completion of the Holocene fluvial terrace surface, the rivers were gentle, and well meandered, and formed continuous higher naturl levees. In time, the rivers deepened, and formed the valleys under the present flood plains according to the lowering of the base level. Burying the valleys with fluvial sediments, the rivers on the flood plains gradually became gentle, developed meander channels again, and formed lower natural levees. At present, the rivers are deepening a little.

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One of the investigated areas is a ridge type slope with convex cross section consisting of thin vegetation at the upper half and dense vegetation at the lower half. Another area is a valley type slope with concave cross section with dense vegetation. The parent material in these areas is weathered sandy tuff.
On the soil formation of this area, it is shown that the thickness of A-horizon varies according to local difference in gradient or vegetation on the slope. On the whole area of valley type slope and on the lower half of ridge type slope, A-horizon is generally thick even where the slopes are steep, then a buried A-horizon is found there. On the upper half of ridge type slope, A-horizon is thin even at gentle slope. On the slopes of either ridge type or valley type, B-horizon is thick at gentle slopes and thin at steep slopes. According to the grain analysis, the soil is rich in fine materials on the valley type slopes and the lower half of ridge type slopes. On the upper half of ridge type slope, the soil is rich in coarse mate
Seemingly, those local differences of soil formation were caused by the differences in slope forms and the density of the vegetation.
First, the slope forms affect the movement of soil materials. It seems that the denudation of slope surface is active on slopes with poor vegetation, and is weak where the vegetation is dense. Therefore the fine materials supplied from surrounding areas are accumulated on the slopes covered with dense vegetation in the lower part of the slopes. In such cases the vegetation is usually poor in the upper part of the slopes.
According to the rapid destruction of vegetation, the denudation is accelerated and so the buried soil is formed at the slope-end. Apparently, the denudation of slope has become active by the human impact to the vegetation since Holocene.
According to the destruction of vegetation, such buried soil as was seen in this slope was formed widely in other areas, too.
In the study of buried soil on slope, the movement of fine materials on the slopes is considered as an important factor for the soil formation except the cases of the aeolian origin such as volcanic ash or sand.

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The lumbering industries in Japan are distributed widely, but it is not even. In this paper the author tries to find their concentration by means of some indexes concern- ing power, labor, and the shipment of raw materials and products. The result is that the main concentrated districts include 13 manicipalities (20.6% among 63 in Iwate Pref.), and they are mainly in the urbanized area and some of them are in rural areas of Kitakami Mountainland. And the location of their industries are classified into the following 4 types: AI type (raw material is conifer within the Pref. and the consumption of the products also within the Pref.), All type (conifers within and products outside the Pref.), BI type (deciduous trees, both within the Pref.), BII type (deciduous trees within and products outside the Pref.), and CI type (imported materials and products within the Pref.).

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Lately, the rapid increase of population in large cities has brought the change of the central quarters within the cities. The author made a study of such secondary shopping streets in Sendai City to analyze their changes of the inner structure. Five examples of such secondary shopping streets examined are selected on the ground of the value of real estates along streets, then the author surveyed the number and frontages of their shops by industry.
In these five streets, the stores for convenience goods still occupy the majority but in four of them, the maen frontage of the stores for shopping goods is larger than that of of the former. It is supposed that these four, reflecting the expansion of residential quarters in the peripheral parts of the city, have fairly highly developed as secondary shopping streets.

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Since 1963, many factories have been established in Osaki district in the northern part ol Miyagi Prefecture where there had been no remarkable manufacturing industries. These factories absorbed laborers from the farm families in this district.
For the farmers and their families engaged in rice culture, it was not easy to change from agricultural into manufacturing work. At first, the families with less than 1 hectare of cultivated land began to remove to factories and later (after 1965) the families with more than 1.3-1.7 hectares followed, then the heads of farming households with less than 1.0 hectare of cultivated land and their wives began to remove to factories.
In the case of non-farming families, it was less restrictive than the case of farming families to remove to factories. However, there is a kind of differentiation between the employees of major factories (mainly electronic appliance industry) and minor ones. The former employed women of self-supporting families and the latter tend to employ women of laborer's families.
But the general tendency can be sometimes modified region by region.

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At Daiichi Dam of the Tachiyazawa River, the amount of dissolved oxygen and the water temperature are observed throughout the day. The hourly observation reveals that the linear relationship (negative correlation) is found to exist between the two. Regarding this river, the following equation is obtained:
DO=13, 98-0.367 Tw (r=-0.933),
where DO is dissolved oxygen in ppm and Tw in °C.

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In the southwest of Hokkaido, there is a very beautiful Fuji-type volcano, called Mt. Youtei or Ezo-Fuji, at the center of Kutchan basin. The basin is filled with Rusuttsu formation which consists of pyroclastic deposits from Toy a caldera. Age of the Toya pumice flow II which brought a depression caldera of Krakatau type, was dated by Minato, M. (1966, Gak-521), and Sato, H. (1969, Gak-868). The present author collected samples that indicate the age of disappearance of the Kutchan lake basin, and dated them (Table). N-927 indicates the age on the beginning of erosion from lake water to fluvial water of Shiribetsu river. N-928 indicates the age of the formation of the lowest river terrace, on which present Kutchan town is situated. It is very significant that there was the Kutchan lake basin, prior to the formation of Toya caldera and Youtei volcano, and that the age of accumulation surface (river terrace surface) of the pyroclastic deposits from Toya caldera was older than the Toya pumice flow II. Youtei volcano is a strato-volcano which erupted during Holocene.

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Directions of the prevailing wind in winter and the maximum snow depths were estimated in terms of the deformation of coniferous trees in the summit area of Mts. Hachi- mantai, which occupy the drainage divide between Iwate and Akita Prefectures.
As a result it is estimated that the prevailing wind in winter is comparatively strong in the area with altitude 1200-1400 m a. s. 1., and its directions are mainly West adding South-components in many places. These South-components are considered to be resulted from the shifts of wind direction' caused by the topographical effect of the WNW-ESE running mountain body to wind directions.
Maximum snow depths are estimated to be 4-5 m in the whole survey area.

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