The distribution of the periglacial area is limited to high mountain areas in Japan at present. But the periglacial areas spread over Hokkaido and mountain areas of central and northeastern part of Japan during the last glacial age. To the contrary, the most part of southwestern Japan were occupied by non-periglacial areas. The ascending of river bed during the glacial age and the descending during the post-glacial age have been pointed out in many upper reaches of rivers in Japan. But it has not been examined precisely whether the amounts of debris supplies and the fluctuations of river bed were different between the regions occupied by the periglacial areas and the non-periglacial ones. Therefore, this paper discusses these subjects.
First of all, the degrees of influences of factors such as the drainage basin area and the relief ratio on the alluvial fan features and structures represented by the variables such as the fan area and the thickness of fan deposit were assessed by factor anlysis (Fig. 2). As the values of factors are given, standard values of the variables are determined for the fan formed corresponding to the factors on the basis of the degree of influence, i. e., factor loading (Fig. 3). The tendencies of the change in debris supplies and of channel fluctuations were revealed by comparing the measured values with the standard values for each period classified as follows:
In the Pacific side of Japan, sediment yields were abundant in the Nakadai Stage (30, 000_??_50, 000 y. B. P.) and the rapid downcutting of river bed proceeded after the stage (Fig. 10). The amounts of debris were small in supply during both the Tachikawa Stage (10, 000_??_30, 000 y. B. P.) and the Holocene. Changes of sediment yields and channel fluctuations in the Coast of the Sea of Japan are in good agreement with those in the Pacific side, whereas channels in the former region have been more stable than those in the latter one. in Hokkaido, the river beds ascended during the period from the Shimosueyoshi Stage (90, 000_??_130, 000 y. B. P.) to the Nakadai Stage. But the small productions of sediments were conspicuous through the Nakadai Stage, the Tachikawa Stage and the Holocene. In the southwestern part of Japan, debris supplies were compara-tively abundant in both stages of the Shimosueyoshi and the Holocene, and channels have been markedly stable since the Shimosueyoshi Stage. The characteristics of sediment yields and channel fluctuations were shown in Fig. 11.
These phenomena for debris supplis and channel fluctuations can be explained by the following hypotheses: It was very cold in the Nakadai and Tachikawa Stage, and there was the smallest quantity of precipitation in the Tachikawa Stage (Fig. 11). A great deal of debris was produced in the source area of the mountain where the periglacial areas spread widely and there was the moderate amount of precipitation, and following it, debris yield was active in the source area where the non-periglacial zone prevailed and there was the large amount of precipitation (Table 1). When the circumstance changed from the non-periglacial condition to the periglacial one and the precipitation decreased, the river bed ascended, whereas, in the opposite change in condition, descending of the channel appeared (Table 2).
Consequently, the amounts of debris supplies in the periglacial areas are considered to have been greater than those in the non-periglacial ones. The amplitude of the channel fluctuation was smallest in the regions where the circumstance did not change from the periglacial condition to the non-periglacial one.

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Characteristics of soil water movement during infiltration are of great importance to study the groundwater recharge. It is also important to clarify the relationship between the type of retaining soil water in pore space and the mechanism of soil water movement.
The purpose of this study is to make clear the characteristics of soil water movement during infiltration, from a kinetic point of view, by experiments on rain infiltration in the vadose zone.
The experiments were carried out using a soil column (15cm×15cm×150cm) with a water table fixed at 140cm below the surface. Artificial steady rainfalls were supplied to the top of the soil prepared in field capacity. Groundwater discharge, matric suctions at the depths of 10cm, 33cm, 58cm, 83 cm, 108cm and 133cm and soil water flux at the depths of 30cm, 80cm and 130cm were measured continuously. To measure the matric suctions and the soil water flux, automatic tensiometers using water manometer and mi-croflowmeters were produced. The former converts a change of capacitance into matric suction and the latter converts a temperature difference into soil water flux. Fig. 1 shows a diagram of the experimental apparatus. Experimental soils used in this study were a sand (0.17mm in median grain size) and two kinds of glass beads (0.066mm and 0.13mm in median grain size) as shown in Fig. 2, whose physical properties were given in Table 1.
The results of the experiments on the rainfall condition of 40mm/h×6 h were shown in Figs. 3 to 5.
The results and conclusions of this study are summarized as follows;
1. Equilibrium water content distributions for each experimental soil are shown in Fig, 6. According to the figure, the vadose zone above the water table should be classified into zones of suspended water, unsaturated water and saturated water, although it is usually divided into unsaturated and saturated zones.
2. Soil water movement in the capillary water zone and groundwater discharge through the water table take place, whenever a wetting front reaches the upper boundary of the unsaturated capillary water zone, which is the maximum height of capillary rise above the water table as seen from Figs. 6 to 9.
These phenomena can be explained by the destruction of static equilibrium between an upward capillary force and a downward gravitational force of soil water in the ca-pillary zone.
3. In the suspended water zone, the downward velocity of the wetting front dose not depend on the soil grain size, but depends on the rainfall intensity (Fig. 10). There-fore, after a beginning of rain, soil water starts to flow faster through the water table in the small grain size soil with high capillary rise than in the large grain size with low capillary rise.
4. The mechanisms of soil water movement depend upon a difference in the type of retaining soil water in pore space. Thus mechanism of soil water movement in the sus-pended water zone is specified by the water held at points of contact among soil particles, while that in .the capillary water zone is specified by the water filled in pores.
Consequently, these flow mechanisms of soil water during rain infiltration are distin-guished between the suspended water zone and the unsaturated capillary water zone.
5. Soil water movement from the land surface to the water table clarified in this study seems to be an important factor to explain the mechanism of soil water movement re-lated to quick groundwater discharge into river on hill slope region after a beginning of rain.

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The topic for this symposium first carves to mind because this particular convention of the Association of Japanese Geographers was held in Hokkaido, an area in Japan which is considered peripheral. The concept underlying the term “periphery” is multidimensional; there are peripheral areas in territories on a national scale in contrast with peripheral areas of care areas ; there are marginal productive areas in the economic sense such as the mountainous areas of a country, developing or dependent countries versus metropolitan or developed countries on a worldwide scale, and so on. The symposium aimed at not only presenting the multifaceted nature of the periphery concept but also at discovering characteristics common to peripheral areas of various kinds and dimensions and the peculiarities of changing dimensions in the periphery concept.
The location of socio-economic activities in peripheral areas cannot be interpreted in terms of abstract economic theories but must be analysed in the context of historical dominancy/dependency relationships, segmentation/integration processes, and the political dynamics of the relationships between centralisation and regional autonomy. The problems concerned require new approaches in geographical studies and, in this sense, the organizers' intent was that the discussions contribute to the progress of methodology in contemporary geography.
The paper session and the general discussion were presided over by Y. Okuda (Chuo Univ.) and K. Takeuchi (Hitotsubashi Univ.). Before the general discussion, the following seven papers and three commentaries were read:
Y. Fuaita (Aiichi Univ.): Characteristics of mountain villages as peripheral areas and some important themes of studies on this subject
H. Sakamoto (tiara Univ.): Agricultural location in the peripheral areas, focussing mainly on cases in Hokkaido
K. Yamashita (Hokkaido Univ. of Education): Public investments in the agricultural sector in Hokkaido
M. Miyagi (Ryukyu Univ.): Excessive imbalances in the location of administrative functions concerning maritime and air traffic and meteorological observation in periphe-ral areas in Hokkaido and Okinawa
T. Ishihara (Okayama Univ.): Regional policies in France, with special emphasis on the case of Brittany
H. Kurihara (Ochanomizu Univ.): he-examination of the “periphery” concept in the case of Spain
M. Koga (Hitotsubashi Univ.): Locational problems in the peripheral areas of developing countries
K. Ito (Keio Univ.) : Commentary on industrial development in the peripheral areas of Japan, in relation with regional policies
F. Mizuoka (Hitotsubashi Univ.) Commentary on the periphery as an internal colony
F. Yamaguchi (Hosei Univ.): Commentary on the emergence and relevancy of regional problems pertaining to peripheral areas
The general discussion which was very animated was focussed mainly on the following four points:
1. The conceptual distinction of “periphery” of various kinds and dimensions and the transcendental meaning of the concept, granting that said meaning exists.
In this connection, the difference between the terms “periphery”, “frontier”, and “border” was also discussed.
2. Problems concerning the articulation of economic aspects with socio-cultural aspects in geography.
3. The mechanism of reproduction/persistency of the centre-periphery relationship.
4. Measures for overcoming the peripheral character.
In tEis connection, questions concerning actual regional policies in Japan and the regionalist movement were discussed.

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Cold regions are featured by most distinctive activities and developments conducted by mankind with much bearing on life. The aspects and concepts of the cold regions might be defined geographically for understanding the relation between human activities and physical environments. Coldness acts on the ground and vegetation in a long geological time. And the characteristic land forms have developed in those regions, while vegetation such as coniferous forests have adapted so well to the cold environments that they have dominated the regions.

This symposium was planned and organized with an aim to understand the characteristics of the cold regions from various viewpoints through interdisciplinary discussions. Those researchers who were invited to participate in it represented the fields of physical geography, plant ecology, glaciology and anthropology.
The symposium had the following five sessions with topics and speakers mentioned together:
I) Cold Regions location and definition in a global scale
^* Cold regions defined by climatology, by Prof. M. Yoshino, of Tsukuba Univ.
^* Cold regions characterized by forest ecology, by Prof. A. Sakai, of Hokkaido Univ.
II) Polar Regions
Glacial erosion and glacial fluctuations in Antarctica, by Prof. Y. Yoshida, of
^* National Polar Research Institute
^* Sea-ice and glaciers in polar regions, by Prof. K. Kusunoki, of the same
^* Submerged topography near the coast of Showa Station Antarctica, and its relation with the advanced ice-sheet from inland, by Dr. K. Omoto, of Tohoku Univ.
III) Sub-Arctic Regions
^* Regional distribution and characteristics of permafrost, by Prof. S. Kinosita, of Hokkaido Univ.
^* Glacial and interglacial alternations in late Quaternary, by Dr. K. Hirakawa, of Yamanashi Univ.
W) Alpine Regions
^* Characteristics of plant ecology in alpine regions, by K. Dr. Ito, of Hokkaido Univ.
^* Characteristics of alpine regions in Japan compared with other alpine regions, by Dr. T. Koizumi, of Tokyo Gakugei Univ.
V) Climatic Changes
^* Climatic changes in cold regions, by Prof. Y. Sakaguchi, of Tokyo Univ.
^* Climatic changes and their impacts on human history, by Prof. K. Okada, of Hokkaido Univ.
^* Paleo-environments in coastal regions in Hokkaido in the post last glacial age, by Dr. K. Endo, of Nippon Univ.
Session I started with Prof. Yoshino's introduction of a variety of classifications of cold regions from the viewpoint of climatology. He pointed out the index of a warmer period such as the monthly mean air temperature of the warmest month during the year, which was the most suggestive in the definition of the cold regions. Then, Prof. Sakai indicated that coniferous forests dominate the cold regions, such distributions of the trees being due to accumulating temperatures during the growing period and to their dormance during the cold period. Besides these thermal conditions, precipitation is also important, he said, adding that boreal forests in the cold regions adapt to the physical environments characterized by coldness and precipitation such as above and that as the results of adaptation, the number of tree species is smaller in the warmer regions.
Session II began with Prof. Yoshido's explanation of the characteristics of land forming process in Antarctica. He also pointed out that glacial erosion dominates in Antarctica, because other fluvial erosions do not occur. In his talk, however, the intensity of the erosion was not examined in detail. Next, Prof. Kusunoki showed the paleo-climatic records obtained from ice-core samples from the Antarctica ice-sheet. He also explained the importance of the sea-ice coverage along the Antarctical Coast resulting in the global climatic changes.

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