The study of man-land relationships in prehistory requires good understandings of many aspects of the geographic environment of the past. Such an environmental reconstruction would be contributed by the geomorphological and palynological methods. This study aims to elucidate the history of man-land relationships in Neolithic period around the lower basin of the Abukuma River with these methods.
Around the lower basin of the Abukuma, many shell mounds of Jômon age have been excavated. At the high sealevel period (B. P. 6, 000-5, 500yr.), the shoreline seems to have been retreated judging from the locations of these shell mounds. But the rate of submergence differed region to region with the local geomorphic elements. Regional differentiation of basic economic pattern of these shell mounds' people was mainly determined by micro-geomorphologic element around settlement site. After this high sealevel period, the sea gradually regressed. The micro-geomorphic environment around shell mounds changed from marine to lagoonal. Following such environmental change, the staple food of shell mounds' people changed from Meretrix lusoria to Corbicura japonica.
The predominant vegetation of early Jômon age was deciduous broad leaved trees, especially Quercus and Ulmus. The climate of this period was warmer than present. In the broad leaved forest, Sus scrofa leucomystax, Cervus nippon nippon lived and these animals supplied important food resource for the specialized hunting people. On the other hand, prehistoric man gathered fruits and roots of plant in the forest. These impact of the prehistoric man destroyed the natural vegetation around settlement site. In the latter half of latest Jômon age (B. P. 2, 500yr.), the climate became cooler and wetter. At this period the predominant vegetation was Fagus and Cryptomeria. The author also studied animal ecology in relation to the change of vegetation and clarified the change of regional food resource of the prehistoric Man.

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Field works and the bibliographical studies on the coastal geomorphology along the southern Sanriku Coast need to re-examine the Pleistocene formations including terrace deposits hitherto so estimated.
Near Kesennuma City, Miyagi Prefecture, it has been said that an unconformity separates the Senganda Formation (the uppermost Pliocene) from the Matsuzaki Formation (the lower Pleistocene). The author's examination suggests that the two are transitional, although partial and slight breaks of sedimentation exist between them as well as within the Matsuzaki Formation itself.
It has also been said that the Matsuzaki Formation distributes from near the present sea level to about 100m a. s. l., and that coastal terraces of various heights cover the same altitudinal extent. The morpho-stratigraphical relation between the two formations and the terraces has not been strictly elucidated.
Along the southern Sanriku Coast, such younger deposits develop widely but sporadically. The area is chiefly composed of the Mesozoic and the Paleozoic strata, then the Cenozoic research on the area has not been intensely done.
Detailed studies on such deposits in the southern Sanriku and its comparative studies with the landforms and the Cenozoic geology of the northern Sanriku seem to be useful for the interpretation of terraces, ria topography, and the identity of younger deposits of the southern Sanriku as well as of the whole Sanriku.
Based on the field data and published ones, the author believes that the equid fossils used to determine the age (as the Würm glacial age) of such younger deposits in the Ofunato Bay district, to the north of Kesennuma, were included in the secondary material derived from the deposits, and that accordingly the fossils there do not indicate the true age of such younger deposits.

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Snow damage is one of the most disastrous of wide varieties of forest disasters. Wet snow on the 15-16th of January 1972, brought disaster to the eastern districts of Iwate and Miyagi prefectures. In Tsuyama, Miyagi precture, the core place of the so-called Tsuyama Sugi (Cryptomeraa japonica), Sugi have been planted since around 1900. Even the stout trees of 20 years and over of age were fallen by snow. The forest damages by heavy snow are different between the coniferous trees and broad-leaves, and the former damages are much severe.
At the mention of aftermath of the forest snow disaster, some damaged wood were chipped for the fiber-using industries and some others were used for timber in paddy field. On the other hand, the local government called for help of the Self-Defence Forces to raise the fallen trees, while many foresters were demanding financial and technical helps of the local government.

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Lake Ohama-ike is northeast of Midagahara lava plateau of the Gassan Volcano. It was formed by landslide of talus deposits supplied from the high cliff at the lower edge of the lava plateau.
The morphometrical data calculated from the bathymetric map of this lake are as follows:
Surface area 1.62×10⁴m²
Length of shore line 578m
Maximum depth 9.10m
Volume 6.24×10⁴m³
Shore development 1.28.
The results of authors' survey are summarized as follows:
The bottom of this lake is covered with talus deposits through which the lake water easily permeate. The amount of seepage is about eight thousand tons per day in summer.
In mid-summer, the distinct development of thermal and chemical stratification is observed in this lake.
The water shows neutral reaction and poor dissolved minerals in which calcium bicarbonate is the main constituent.
From the low photosynthetic productivity and the negative correlation between dissolved oxygen in the water and water temperature, it is inferred this lake is an oligotrophic lake.

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The terraces along the Hirose river well-develop especially in the Ayashi basin, and in the urban area of Sendai. They, however, often disappear in the gorge between the two areas mentioned above. These terraces have been studied by several researchers. The present writer tried the re-examination of terrace classification and correlation especially from the viewpoint of the influence of the crustal movement on the terrace surfaces.
In addition to the tephrochronological method, the thickness of the weathering crust of terrace gravels is used as an index for terrace classification and correlation, as proposed by Akojima et al. (1971).
The present writer's terrace classification and correlation is shown in Fig. 1. The writer found displacements of the terrace surfaces in the Ayashi basin and in Sendai which suggest the continuous crustal movements (Fig. 2). It is considered that these displacements are due to flexures with axes of N-S direction in the Tertiaries. Such crustal movements are more remarkable in the upper stream area, and seem to have been continuing with uniform velocity.

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Regional differential of fertility among cities appears to be affected by the fertility level of the region in which they are, as well as by their size and function. Using the data of “Average issues per ever-married Japanese woman 15 years old and over” reported in Japanese Population Census in 1960, we can divide whole Japan into three regions with differential fertility level (fig.). The author chose 97 cities having 50, 000-200, 000 population in their “Densely Inhabited District” as medium sized cities to culculate the average births per woman in the age category 20-49 by the region (table). This table reveals that there is a strong and consistent correlation between the fertility level of cities and the surrounding region.

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The figure shows the rates of the branch offices to all the establishments in the main rental buildings in Sendai. The average rate to Sendai city as a whole is 53.6%, while it amounts to 70.1% in its central district. Additionally, it is higher in the larger buildings than in the smaller buildings in the central district.
The comparatively higher rate occupied by the branch offices in the rental buildings depicts that Sendai is a regional central city promoted by the branch offices.

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