For precise reconstruction of late Holocene sea-level fluctuations, which seem to have affected the formation of various coastal landforms over a wide area, a narrow valley bottom plain facing a small inner bay provides a suitable site for field research work. In this area, changes in the sedimentary environment are caused simply by sea-level fluctuations; no disturbance is induced by the development of bars or beach ridges, because wave action and coastal currents are usually too weak to form them.
In the study reported in this paper, late Holocene sea-level fluctuations were reconstructed on the basis of diatom analysis at 133 horizons in 10 locations and radiocarbon dating at 19 horizons in 8 locations on two valley bottom plains facing Matsushima Bay, a small bay in the innermost part of Sendai Bay, northeastern Japan. The results are summarized as follows.
1) The results of diatom analysis and radiocarbon dating on the Takagi-Nemari valley bottom plain (Fig. 3-7) have revealed two transgressions, indicated by diatom zones MI and MII, in the period between 5, OOOy. B. P, and 3, 350y. B. P. (Fig. 13).
2) Careful tracing of the boundary between marine deposits and fresh-water deposits has made it possible to reconstruct successionally the following sea-level fluctuations.
Sea level rose slowly until 4, 800y. B. P. The upper limit of marine deposits formed under the influence of the sea-level rise is 0.4m above the present sea level. Between 4, 800y. B. P. and 3, 900 y. B. P., sea level was stable; after that time, it began to rise again. The maximum level of the later sea-level rise had an effect on the sedimentary environment at about 2m above the present sea level. After 3, 500y.B.P., the sea level began to fall. The upper limit of the tidal effect fell to +1.5m at 3, 350y.B. P., and to +1.0m at 2, 200y. B. P.
However, the mean tide level at each time is estimated to be 0.64m below the above-described boundary between marine deposits and fresh-water deposits indicated above, on the assumption that the tidal range has not changed from the late Holocene time to the present.
3) In comparison with the living diatom assemblages on the tidal flat and the bottom of the shallow sea (Fig. 14, Table 1) the results of diatom analysis and radiocarbon dating on the Tedaru valley bottom plain (Fig. 9-12) shows that the sea level fell to c. 1.5m below the present level for a time after 2, 200y. B. P.
4) Results of diatom analysis and radiocarbon dating at Loc. Ta-3 (Fig. 8) indicate that the sea level of 6, 500y. B. P. stood at c.lm below the present sea level.
Figure 15 represents the reconstructed sea-level fluctuations.

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Japanese rural areas have experienced deep socio-economic changes since the rapid economic growth period after World War II. Since the 1970s a new type of community, a “rurban (rural/urban) village, ” has appeared in the suburbs. This area has been accepting of newcomers. And farm households in this area tend to diminish or to abandon their farming. As a result, the rural community has been changed by both inside and outside factors.
This paper aims to examine the structure of rural community in the rurban village, focusing upon the mixture of established residents and newcomers. The results obtained in this paper are as follows:
The study area, Nakanakajoshi, is located in the northern suburbs of Hiroshima city. In spite of its intensive agriculture, this area has been accepting newcomers who reside in either owned or rented houses since the 1970s. This steady flow of immigration causes urban encroachment on farm land.
Farm household management has diversified into several types: intensive agriculture, real estate, or non-agricultural employment by urban industries. The newcomers can be divided into two types: permanent dwellers, who wish to dwell eternally, and temporary dwellers, who wish to move again in a few years.
The author tests the significance of differences among types of inhabitant for participation in neighborhood groups, participation in local activities and for local consciousness. Large differ-ences are seen between established residents and newcomers. Moreover, intra differences can be seen in every type. The factors associated with a difference in every type are the style of agricul-tural management in the established residents and the will of establishing in the newcomers.
The following 5 types are found in this analysis.
1. Established residents
1. Farm households engaged in intensive agriculture. They are extremely interested in local affairs and play a leading part in local autonomy, cooperative projects, and festivals, They are eager to have contact with both other established residents and newcomers. They oppose improving the infrastructure when it requires their own farmland, even though there are serious problems with the lack of infrastructure facilities such as roads, parks, and community centers.
2. Commuting farm households. They are concerned about local affairs and eager to have con-tact with other established residents but not with newcomers. They, like the following three types of residents, are not content with the present state of the infrastructure.
3. Non-farm established residents. They don't take a positive attitude toward local affairs such as agricultural cooperative projects or cleaning an irrigation channel. They are not eager to have contact with either established residents or newcomers. II, Newcomers
4. Permanent dwellers. They are more interested in local affairs than temporary dwellers. Some of them try to make contact with established residents by attending the KOH, the Buddhist neighborhood meeting, and try to blend in with the established residents.
5. Temporary dwellers. They are indifferent to local affairs, because they plan to move again in a few years.
Farm households engaged in an intensive agriculture take the leadership in the rural communi-ty, though they are no longer in the majority. In particular, rural self-government organizations cannot function, or traditional local events be held, without them. Therefore, it can be said that even though the “metropolitan village” will accept newcomers, the function of rural self-governing organizations and traditional local events can be maintained only as long as there are farm house-holds engaged in intensive agriculture in rural communities.
Newcomers tend to be resent the established residents in local concerns.

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The Hatenohama sand cays located at the eastern end of Kume Island are the largest coral sand cays in Japan, with a total length of about 6 km and a width at the widest point of 300m. The aim of this paper is to describe the long-term changes in shorelines along the Hatenohama sand cays caused by typhoons.
Vertical aerial photographs were taken 5 times in the period between 1962 and 1984. Shoreline changes in the sand cays were measured with a digitizer from these aerial photographs. In order to compare changes of intertidal and subtidal sand areas in the areas surrounding the sand cays, image enhancement techniques were employed on these photographs using a personal computer system and a CCD camera.
Typhoons and their wind data recorded at the Kume Island Weather Station over the period 1.962-1984 were analyzed. During those 22 years the number of typhoons wihch approached Kume Island was 126. Wind energy resultant vectors were calculated using the wind velocity and the wind direction at the times when typhoons passed near or over the island.
The analysis of sand cay shoreline changes and wind date of typhoons for the period 1962-1984 at Kume Island indicated that the changes of shorelines reflect changes inn the wind-induced waves. Shoreline changes occurring since 1962 were related to the wind-induced waves from the south associated with the occurrence of typhoons. Significant changes have occurred since 1970. Con-siderable quantities of sand have moved, exposing beach rocks on the southern beach and covering formerly exposed beach rocks on the northern beach. Because of the strong south wind, the south sides of the cays experienced ramparts erosion, while the sandy beaches on the northern sides increased in area.
It was found that the shoreline changes and changes in the shapes of the sand areas surrounding the sand cays occurred frequently.
However, the long-term trends of shoreline erosion/accretion patterns and the changes in mor-phology of sand areas are not clearly understood.
This study shows that the eastern and the western ends of the sand cays have been elongated and significant changes have occurred, On the other hand, the middle of the southern beach has suffered little or no shoreline change, with the beach rock being extensively exposed for the length of about 1km. It is assumed that the beach rock supports sandy sediments and protects the shoreline from wind-induced wave erosion.

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