In this paper, the author examines the spatial cognition of and navigation in a Japanese city by different ethnic groups. The purpose of this study was to identify any uneasiness that the subjects Japanese-Brazilians living in Japan, feel in finding their way in a city in Japan by studying the clues they use for navigation and their cognitive maps in comparison to those of a Japanese group.
This study consists of two approaches. First, the author used the Sense of Direction Questionnaire Simple Version (SDQ-S) developed by Takeuchi (1992) to study how one's consciousness perceives navigation and space. The author obtained responses to the questionnaire from 41 Japanese-Brazilians and 252 Japanese college students and compared the scores of the responses to the questionnaire by item and conducted a factor analysis. As a result, it was found that Japanese-Brazilians had a poor sense of directions and that it was important for them to use and remember landmarks for navigation.
Next, the author focused on the fact that landmarks play a significant role in their navigation and conducted two types of sketch map survey. In the first type, the subjects were asked to draw a sketch map of a route to identify the features of the landmarks they used as clues. In the second type, they drew a sketch map around their own homes to examine the differences in the space areas and forms perceived. Analysis of their sketch maps of a route found that stores and traffic lights with signs written in the Roman alphabet or Japanese kana characters that they could read were important landmarks used in their navigation.
Regarding the sketch maps around their homes, the author conducted quantitative analysis of the area drawn on the map, number of factors drawn, forms of drawing, and direction. The sketch maps by Japanese-Brazilians covered a much smaller area and had fewer factors than those drawn by Japanese. They all drew route-type maps regardless of the number of years that they had resided there. Transition from route-type maps to survey-type maps was not seen based on the number of years they had been there. This means that the cognitive maps of Japanese-Brazilians do not undergo the typical development process to survey-type maps even if they live in Japan longer.
Based on these results, the author considered the factors hindering the development of cognitive maps of Japanese-Brazilians from route-type maps to survey-type maps. Japanese-Brazilians may be affected by their limited Japanese language proficiency, the fact that the streets and house numbers are marked in different ways in Japan, different cultural backgrounds, and unfamiliarity with the Japanese landscape and urban structure, The author assumes that they have route-type cognitive maps and their navigation in Japanese cities is limited to the use of certain landmarks for these reasons.

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The sediment supply caused by the erosion processes peculiar to Quaternary volcanoes often plays an important role in the landform development of the downstream part of drainage basins. In particular, the sediment derived from the large-scale destruction of volcanic cones has great potential to modify the landform of drainage basins. Therefore the author attempted to elucidate the geomorphic development of the Maebashi and Takasaki area located in the middle reach of the Tone River drainage basin which had Quaternary volcanoes in the upstream area focusing on the relationship between large-scale volcanic events and the river process.
This study found that the debris avalanche called the Maebashi Mud flow derived from the Asama volcano and the newer volcanic Inokawa Mud flow strongly influenced the geomorphic development of the study area. The results can be summarized as follows:
1) The Tone River formed a vast alluvial fan in this region around 25, 000 years ago.
2) Around 24, 000 years ago, the Maebashi Mud flow was deposited over the entire area and changed the landform dramatically as represented by the decrease in gradient and the elevation of ground level. The prototype of the Maebashi surface was formed at this time.
3) After deposition of the Maebashi Mud flow, the Tone River and the Karasu River started incising the depositional surface markedly. The former was fixed to the west and the latter was fixed slightly to the north compared with the present river courses. On the Maebashi Mud flow depositional surface, the Maebashi Peat layer began to be formed simultaneously with the decrease in gradient.
4) From about 16, 000 years ago, the Tone River shifted to the east and incised the Maebashi Mud flow depositional surface again. As a result, the Hirosegawa Gravel layer composing the Hirose surface was formed.
5) About 11, 000 years ago, Inokawa Mud flow flowed down the Karasu River channel. The Takasaki area was covered with this deposit, resulting in the formation of the Takasaki surface. The main channel of the Karasu River shifted to the present position.
6) As the Ino River slightly dissected the eastern part of the Inokawa Mud flow depositional surface, the Ino surface was formed as an erosional one.
Based on the above, the author concluded that the geomorphic development of the study area was strongly related to the sediment supply by volcanic events in the upstream area and that it is necessary to reevaluate the Quaternary volcanoes as the sediment source involved in the landform development of the downstream part of the drainage basin.

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In this study, the author analyzes the development of full-time farms in the urban fringe of the Tokyo metropolitan area and clarifies their sustainability on a micro-scale using the example of the Takabatake area, Saitama city, Saitama Prefecture. In this area, many full-time farms are maintained by diversified farming. Each farm has adopted new crops and expanded diversified farming to respond to economic and social changes. In this area, the physical, social, institutional, and regional environments have made it possible for farms to adopt a succession of new crops and maintain diversified farming. In particular, the physical environment characterized by lowlands and plateaus has made it possible to combine paddy rice and vegetable production. The social environment characterized by homologic unification has made it possible to supplement the shortage of labor. Access to markets in the metropolitan area has made it possible to adopt commercial crops like arrowheads and flowers. As a result of the introduction of various crops, each farm participates in a division of labor and leveling of income and labor supply.
Furthermore, diversified farming helps each farm not only to level income and labor supply but also to incubate successors. In this area when adopting new crops, farmers have handed over the new business to their successors. As a result, the successors have developed the business in their own way and maintained full-time farms. In the Takabatake area most successors had engaged in business in markets for agricultural products before engaging in agricultural management. This has influenced farm management in the Takabatake area. Concretely speaking, they developed networks with various markets and then introduced new markets to the Takabatake area. As a result, most farms send various crops to various markets. Each farm has overcome the risk in successors' adopting new crops and new markets by maintaining traditional crops.

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