Despite its population of only 8.7 million, Sweden boasts of human geography which is highly respected around the world. The Lund school is known worldwide as having laid the cornerstone for theoretical and quantitative geography. There are also numerous Swedish human geographers of high stature in the International Geographical Union (IGU), as well as international research coordinators for such organizations as the United Nations, the World Bank, and UNESCO. Within their own country, Swedish human geographers have come to occupy important posts such as government legislators, university presidents, and directors of research institutes. Many human geographers also work in government and commune planning departments, and their opinions and advice for the formulation of regional policy are widely reported in the media. In Sweden, human geography is maintaining considerable influence in national and regional planning. Swedish human geography is an applied social science which seeks to resolve problems and issues. Not only are research themes and interests closely related to social conditions and policies, as one would expect, but even theories and methods developed by human geographers sometimes have such a relationship. The mass migrations to the cities in the 1950s led to the development of population movement theories, urban spatial structure theories, and predictions of future traffic flow, as well as research in the optimal placement of public and private facilities. The National Settlement Strategy, a plan formulated in the early 1970s, strengthened urban systems theory, central place theory, and industrial location theory, among others. The emergence and development of computer cartography in the 1960s was supported by the government's “geo-coding” policy for real estate and resident registration. And the Social Democratic Party's long-term policy to achieve an equal and just society which respects individual rights has always had a relationship with the development of temporal geography. We can therefore see that the theories and models of Swedish human geography have been created not by superficial considerations but through verification research, that is, they have been inductively derived by compiling the results of numerous case studies. Theories and models are, in effect, little more than methods, the development and use of which have provided effective means for solving problems. In the 1960s, human geography in Sweden was not absorbed in the quantitative spatial sciences which were sweeping the world at the time, because the boom in theoretical and quantitative geography did not happen here. The original quantitative methods and theories developed in Sweden were received with acclaim by international geographical circles, yet all the while the research of the Swedes themselves was not concerned with techniques and models but with processes and the structure of social space. This likely has something to do with Sweden's low population and population density. Or perhaps it could be a reflection of the respect of the Swedish people for individuals and individual rights. Rather than macro research, which concerns itself with regional and distributional differences, Swedish human geographers prefer research of small regions at the non-aggregate level. This trend is believed to have been gradually strengthening in recent years against the backdrop of the diffusion of decentralization policy and the maturation of the individual-and consumer-oriented societies. Fields in which interest is particularly high and which will probably become more active in the coming years include environmental issues, preservation of the cultural landscape, community research, gender geography, international economic geography, and Third World studies.
We made a detailed tephrochronological study in the western and southern foots of Hakone Volcano and revealed the eruptive histories of Hakone and other volcanoes since 240 ka. We recognized four widespread tephras, Aira-Tn Ash (AT), Sanbe-IkedaAsh (SI), Kikai-Tozurahara Ash (K-Tz) and Ontake 1 Pumice (On-Pm1) as well as the tephras from the adjacent volcanoes, such as Hakone-Mishima Pumice (Hk-CC4), the pyroclastic flow associated with Hakone-Tokyo Pumice (Hk-TPfl), and Hakone Da-5 Pumice from Hakone Volcano, Fuji Susono-1 Scoria and Fuji Susono-2 Scoria (F-Sul and F-Su2) and Fuji-Yoshioka Pumice from Fuji Volcano, and the tephras from the Higashi-Izu monogenetic volcano field. Eruption ages of F-Su2, F-Sul, Hk-CC4 and F-YP are estimated to be 36 ka, 37 ka, 43 ka and 85 ka, respectively, by loess-chronometry. The discharge mass and eruptive magnitude M are estimated to be 3.7 × 1011 kg and 4.6 for Hk-CC4, and 4.2 × 1011 kg and 4.6 for Da-5 Pumice on the basis of their isopach maps. The eruption frequency in the study area is 0.11 times/ ky for the last 240 ky in average, showing an abrupt increase to 0.53 times/ky during 120 ka-135 ka. In this period, both Hakone Volcano and the Higashi-Izu monogenetic volcano field seem to have been active simultaneously. The loess thickness, which is interbedded between Hk-CC4 (43 ka) and Hk-TPfl (52 ka), tends to increase toward the eastern foot of Fuji Volcano. The age-depth diagram shows that the accumulation rate of loess is nearly constant in each locality except for the rapid increase at about 50 ka in the Kannami area. The linear accumulation of loess supports the validity of loess-chronometry. The 50 ka increase of loess accumulation rate seems to be associated with enlargement of barren plains, which were located in the eastern of Fuji Volcano and were probably the main source of loess materials.
Iwo Jima is small volcanic island located isolate in the Western Pacific Ocean about 1, 250 km south of Tokyo. The island with the area about 23 km2 is covered with considerably dense vegetation and no rivers exist in this island. Thus, the source of sediments to nourish the beach seems to be quite limited in this island. Further, the coast is always subjected to rough seas because it is fully exposed to the open sea. Nevertheless, the coast is mostly rimmed by sandy beaches with about 200 m in width and the shoreline is still advancing toward the sea which increases the beach area year by year. Many scientists have pointed out that this increase might be caused by an unusual upheaval of this island exceeding 30 cm per year. However, no quantitative analyses have been done yet on this unique phenomenon that prevents from constructing any port facilities in this island. Thus, the author intends to investigate the features of the long-term variation of the area which have occurred in Iwo Jima during the past seven decades and to examine its variation mechanism. To investigate the features of the long-term variation, analyses are conducted on the seven maps and charts of Iwo Jima which have been published in the period from 1911 to 1981. The analysis reveals that the island has kept increasing its area over the past seven decades although the increasing rate has changed drastically in 1952 from 30, 000 m2 to 90, 000m 2 peryear and that the increased area has reached roughly 4.3 km2 in total during the sevendecades. This change of the increasing rate well corresponds to the fact that the upheaval rate of the island has changed in 1952 from roughly 10 cm to 30 cm per year which has been found by Kosaka et al. in 1979. To examine the effect of the upheaval on the features of the long-term variation of the area, calculation is carried out by giving the various values of imaginary upheaval to the bathymetric data shown on the chart covering the sea around Iwo Jima published by the Hydrographic Department of Japan Maritime Safety Agency in 1981. The result of the calculation indicates that the upheaval of 10 cm per year corresponds to the increasing rate of the beach area roughly 43, 000 m2 per year and the upheaval of 30 cm per year corresponds to the increasing rate of the beach area roughly 130, 000 m2 per year when the foreshore slope is assumed to be 1/20. These values are surely the ones before the beach is transformed by the action of the ocean waves. However, comparison of these values with the ones found through the former analyses indicates that the calculation has provided quite a reasonable estimation of the increase of the beach area. These findings clearly indicate that the continuous upheaval is the governing factor to cause the increase of the beach area in Iwo Jima.
Two aspects of the hydrological change in Tokyo are analyzed in this paper. The first is the changes in river courses, canals and open aqueducts from ca. 1890 to ca. 1985. The position of surface waters were traced from the topographical maps. Average stream density in the 23 special wards area except for three wards in the eastern lowland was 1.4 km-1 during a period from 1890 to 1910, while it reduced to 0.49 km -1 in 1985. In several wards, the density reduced to less than 10 % during this 100 years. The diminution of small rivers and canals began as early as 1920's, and many of them disappeared by 1985. The reduction of surface waters is closely related to the diffusion of municipal water supply and sewerage system, therefore, the water balance caused by the man-induced water transport was estimated for the recent about 40 years. The water balance was calculated for each ward and city for each 10 years interval. Data were taken from several kinds of statistics on waterworks and “Statistic Yearbook of Tokyo”. The total water supply includes the municipal water and the industrial water. The annual amount of total supply expressed by water depth (height) was about 6 m during 1960's and 1970's in the central district of Tokyo, that is, about four times of the annual rainfall in Tokyo. The depth of total water supply exceeded the annual rainfall in all the 23 special wards in 1970's. The consumption and supply of water have been reduced since 1980's according to the establishment of recycling system. Because of the high supply rate, the depth of seepage from underground pipes of the waterworks amounted to 1 my-1 in 1975 in the central wards. The first sewerage system was established in 1920's, but the coverage for all the areas in Tokyo was not completed until the recent. Therefore, more than 1 my -1 of the untreated water had been discharged from several wards before 1980 causing the high pollution of rivers. Historical changes in surface waters and their pollution can be explained in connection with the changes in man-induced water balance. It must be emphasized, that the artificial water transport is a crucial element in understanding the urban hydrology.