Much attention has been devoted to the changing structure of metropolitan areas due to population dispersal. In the latter half of the 1990s, however, population recovery was reported in the central parts of large Japanese cities such as Tokyo and Osaka, suggesting a reversal of population redistribution in metropolitan areas from dispersal to reconcentration. This trend may indicate a turning point in the structural development of metropolitan areas.
With this in mind, the purpose of this paper is to examine the spatio-temporal structure of population growth in Japan's metropolitan areas in detail. The expansion method, which assumes spatiotemporal continuity of population growth (1965-2000), is employed as the central model, and the spatial structure of population growth in the near future (2000-2005) is forecast based on the application results. The objects studied here are the nine major metropolitan areas in Japan. To delineate metropolitan areas, the Standard Metropolitan Employment Area (SMEA) advocated by H. Yamada and K. Tokuoka was used. The major findings obtained are summarized as follows.
Although a decrease and a leveling off of the population growth rate and population dispersion were common to all of the SMEAs until 1990, a difference was found both in the process of dispersion and in the trend after 1990. First, in Tokyo, Osaka, and Fukuoka, although centrifugal movement of the center of population growth had been under way until 1990, a shift in population redistribution from decentralization to reconcentration was confirmed after the mid-1990s. Second, in other SMEAs, the center of population growth remained in zones 10-15 km away from the metropolitan center until 1990. A noteworthy distinction was detected for the period starting from the latter half of the 1990 s. In Nagoya and Kyoto, although population recovery around the city center was also seen, it was only a change from absolute to relative dispersion. In Sapporo, Hiroshima, and Kitakyushu, however, population recovery around the city center was not seen and an overall decline was forecast for the near future.
With respect to the variation among the SMEAs, a few possible factors are raised as working hypotheses. First, there may be a difference in the type of population pressure on land use, mainly due to different population sizes and topographical conditions. Second, the differences in urban functions might also be important because these factors are assumed to make a difference in the accumulation of professionals, managers, and information industry workers, who are forecast to be the impetus behind population recovery around the city center. Additional reasons for this population recovery may be the increase in large-sized condominiums due to the recession, diversification of households (including a rapid increase in the number of one-person households), and the restructuring of the metropolitan economy.
The above-mentioned results are different from those predicted by Klaassen's hypothesis of metropolitan development. According to that hypothesis, the stage of reurbanization is assumed after depopulation of the metropolitan area, but a population increase has continued in the major metropolitan areas in Japan. Moreover, land prices fell greatly due to the recession of the 1990s, and a large amount of surplus land was released in the major cities in Japan. It seems likely that the population recovery around a city center might be confirmed before the population of the metropolitan area decreases, implying a different result from the one expected in Klaassen's hypothesis.
The analytical framework of the expansion method assuming spatiotemporal continuity yielded the interesting findings described above. However, this method did not incorporate sectoral differences in metropolitan population increases, and goodness-of-fit was not sufficiently high due to the detached (or noncontinuous) increase/decrease in population.

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The author researched the Holocene sediments and geomorphic evolution of the Kumozu River lowlands using diatom analysis, electric conductivity, and ¹⁴C dating, and discusses how the sedimentary environment changed during the late Holocene. The results are summarized as follows.
1) After the Holocene transgression, sedimentation of upper marine sand in the southern lowlands proceeded to the northern lowlands and began to accumulate around 4, 800_??_4, 300 cal. BP. It is possible that the earlier river channel was in the southern lowlands and a shift of the river channel toward the north caused the difference in the depositional age.
2) Three beach ridges finished forming before 2, 600 cal. BP, 1, 600 cal. BP, and the present, respectively. Beach ridge I, which formed before 2, 600 cal. BP, developed straight along the coast, while beach ridge II, which was formed before 1, 500 cal. BP, extended toward the sea around the river mouths. This suggests that the coastal lowlands was first dominated by waves, although it was dominated by the river after 2, 600 cal. BP and before 1, 500 cal. BP.
3) Two flood sand layers are found in fluvial deposits. Flood sand I is relatively coarse and was deposited before 3, 000 cal. BP. The terrestrial environment was stable for a short period during 3, 000_??_2, 200 cal. BP. Flood sand II began to accumulate from 2, 200 cal. BP and it is finer and better sorted than flood sand I.
4) Based on the increase in the thickness of the upper marine sand, the distribution of beach ridges, and sedimentation of the flood sand layers, it is assumed that the sediment supply increased after ca. 2, 000 cal. BP. This environmental change appears to be common to the Pacific coasts in central Japan.

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Recently, there have been many arguments about the consolidation of municipalities in Japan to promote decentralization. The consolidation of municipalities has many advantages and disadvantages. Although numerous geographical studies have dealt with the consolidation processes, few have focused on the influences of the consolidation upon the region concerned.
The purpose of this study is to show the characteristics of municipal policies in a regionally consolidated municipality. The author examined the distribution of public investment. Ichihara City, Chiba Prefecture, was chosen as the study area, where seven municipalities with nearly the same scale were consolidated in the 1960s. The results of this study are summarized as follows:
(1) There were two major reasons for the consolidation to form Ichihara City: the construction of a coastal industrial region and rapid immigration of population as a result of industrialization. In the 1960 s and 1970s, therefore, city management policies in Ichihara City put special emphasis on the construction of infrastructure. Public investment in this period was allocated intensively to the coastal part of the city, in particular, to existing built-up areas. City planning projects, such as land readjustment and road building, and the establishment of new schools were carried out in succession in this area.
(2) In the 1980 s, the reaction against the practices carried out led to a reduction in regional imbalance in municipal services. As a result, the city authority promoted the establishment and remodeling of public facilities in the southern part of the city, where the population remained unchanged or decreased. Public investment spread through the entire municipal area.
(3) In the 1990 s, after the completion of public facilities, the municipal master plan called for constructing the central built-up area. This policy resulted in the construction of large-scale facilities in the Goi district, which was designated as the city center. Consequently, public investment in this period was concentrated in a specific district.
(4) The expansion of the volume of public funds in Ichihara City accelerated the city planning projects and the establishment of various facilities. However, it is still necessary for the city authority to maintain a balance among the former municipalities. The sense of “separation” in the municipal administration has been greater than that of “integration.” A little progress has been made in the formation of the city center for a population of this size.

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