カール内の植物群落は,地形,微気象(消雪時期,受光量,風など),地表面構成物質の性状と安定性など多くの環境要因の相互作用を受けて成立している.群落の空間的分布に対し,地形はこれらの要因の中でもっとも主導的な役割りを果たしている.地形と植生の間には次のような関係がある.1)カール内では,多くの地形がある程度定まった位置に形成されている.このため,カール内では地形の形態(凹凸)とその地形が一般に形成される位置(斜面方向)によって,消雪時期が特定化され,消雪時期の差が植物の生育期間や嫌雪性などの要因を通して群落の分布に影響を及ぼす.したがって,地形によって分布する群落が限られる.2)ただし,崖錐のように,形成される場所が不定の地形の場合,その地形の斜面の向きや場所によって風の強さや受光量に差が生じ,その結果,消雪時期,ひいては植生が多様になる.3)地形が消雪時期-植生に及ぼす影響については,(a)その形態(凹凸)がとくに重要な場合と,(b)その地形の占める位置(斜面方向)がとくに重要な場合があるが,(a)の場合は凹型・凸型斜面,(b)の場合は平滑斜面であるのが一般的である.4)地形は地表面構成物質の分布と性状に影響を及ぼし,この違いが土壌水分や地表の安定度などの要因を通して,群落の分布に影響を及ぼす.

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Gentle mass movement caused by the freeze-thaw process is very important on slopes in the alpine zone. In Japan, the mass movement process and weathering caused by the freeze-thaw process are being clarified by field experimental research. However, on the actual conditions of air temperature and soil temperature which provide for freeze-thaw processes, little research has been done, and the results are not reported in detail. Because of this the author observed air temperature and soil temperatures at 2 cm, 5 cm, and 10 cm depths continuously on the top slope of Mt. Hoo, in the northeastern part of Japan's Southern Alps (Figs. 1 and 2). The observation period was from September 24, 1986, to June 8, 1987 (258 days; absences: 15 days).
As a result of this observation, the changing pattern of air temperature 1.5m above the ground surface is seen to be similar to the temperature of soil at 2cm depth. The trend of 5cm depth soil temperature is similar to that of 10 cm depth soil temperature. The diurnal cyclic freeze-thaw process is evident in air temperature and 2 cm depth soil temperature (Fig. 4). This is caused by surface rubble layer distributed below 2 cm depth (Fig. 3). The air temperature affects the 2cm depth soil temperature. However, the 2cm depth soil temperature rises over air temperature because of solar radiation, and it actually promotes the thawing process in the 2cm depth soil layer, even when the air temperature is below 0°C. This process notably occurs in the thawing period.
The 5cm and 10cm depth soil temperatures show cyclic changes which are not directly affected by air temperature. During the observation period, 5cm and 10cm soil temperature stabilized at -1.5_??_-2°c for a specified period. The stabilization is caused by latent heat release when soil freezes and latent heat absorption when soil thaws; this is the so-called zero-curtain phenomena.
Changes in soil temperatures are steeper in thawing periods than in freezing periods (Fig. 5). Soil temper-atures rose sharply and dropped gently during the observation period.
In the thawing period, the range of diurnal change in the 2cm depth soil temperature exceeds that in air temperature caused by solar radiation. As a result of this process, the number of freeze-thaw days at 5cm and 10cm depths increases in the thawing period. The 2cm depth soil temperature rises before the air temper-ature rises in the latter half of the freeze period and the first half of the thaw period. This occurs due to solar radiation. The small-scale fluctuation of air temperature and 2cm depth soil temperature above 0°C is caused by temporary masking of solar radiation by clouds or fog.
As described above, on the top slope of Mt. Hoo, the solar radiation has a very strongly effects on the mass movement of the dopes. This tendency occurs most markedly near the surface.

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This symposium was organized to discuss with Association members the findings of the Geographical Education Committee of the Association of Japanese Geographers. Since the first meeting in September 1986, the committee has held thirty meetings. In addition, an earlier symposium, an international meeting, and a local joint meeting with the Toyama Earth Science Society were organized. Through these meetings, the committee examined, analyzed, and discussed the following themes:
(1) Geographical education at the primary, secondary, and tertiary levels.
(2) Geographical education in terms of physical environments.
(3) Geographical education in terms of area study and excursion.
(4) Geographical education and placenames.
To expand these themes, the following reports were presented (the names with asterisk are those of members who served as reporters):
(1) T. Kubota^*: A review of the background of the “Geographical Education Committee” and its activities.
(2) H. Iwamoto^* and K. Yoshida: A proposal for improving geographical education in primary schools and a report on a pilot survey of place-name recognition among the public-non-geographers.
(3) K. Asakura and K. Hirasawa^*: A proposal for improving geographical education at the lower secondary level.
(4) T. Inui, T. Kusakabe, T. Kubota, Y. Nishiwaki, and H. Mori^*: A Proposal for improving geographical education at the upper secondary level.
(5) R. Asakura^*, T, Kimoto, I. Komine, Y. Sato, T. Shirai, A. Shinohara, and M. Nakayama: A proposal for training undergraduates to be better qualified geography teachers.
(6) T. Nishizawa, T. Bekki^*, and Y. Yamada: A proposal for improving geographical education in the liberal arts course in tertiary institutions.
(7) T. Shirai^*, M. Nakayama, T. Nishizawa, and other members: A proposal for improving geographical education in terms of physical environments, especially at the upper secondary level.
(8) T. Inui^*, T. Kimoto, I. Komine, A. Shinohara, Y. Yamada^*, and other members: Some proposals for improving area study and excursions at various school levels.
After a comprehensive comment was given by T. Nishizawa, a final free discussion was held among participants. An hour was not necessarily enough an in depth discussion, but the following points were stressed:
(1) Many questions focused on the relationship between the proposals of the committee and the “Revised Course of Study” which presented the Ministry of Education's national guidelines for the curriculum although the Association took a neutral position with regard to the Revised Course of Study.
(2) The activities of the committee should be continued after March 1990, when the current members' terms will expire.

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Land use is an important subject of geography, but it has largely been dealt with as a subordinate part of other subjects, such as urban geography or agricultural geography, Consequently, it has failed to make systematic progress, and nation-wide comprehensive studies have been rare.
The Land-use Working Group, which is responsible for the current symposium, was established five years ago as a study group, in order to organize land-use researchers for the enhancement of the traditional but then somewhat disorganized research field. The group has so far held ten meetings, including an international symposium which was convened three years ago.
Among the group's achievements are that land use has come to be recognized as an important research subject and that many land-use researchers, whose interests range from urban to rural and from Landsat to policy, were organized. The present symposium is intended to contribute to the exchange of information and views regarding various aspects of land-use change and its related problems, based on recent research achievements within and outside the working group.
The subjects of this symposium include land-use policy issues as well as more basic data collection and analysis, while the previous symposium was mainly concerned with the latter. It consists of the following four sub-themes:
(1) Provision and use of large-area data.
(2) Urban land-use change and its related problems.
(3) Rural land-use change and its related problems.
(4) Environmental management and planning.

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Since the 1960s tourism and recreation in Japan have changed remarkably in many respects, and have induced rapid transformation of areas devoted to tourism. The purpose of this symposium was to discuss the recent changes brought about by tourist and recreational activities. It was also an aim of the symposium to examine what kind of materials and data are useful for the geographical study of tourism.
The reporters and their themes were as follows:
(1) T. Ukita, T. Kagawa, S. Koga, T. Fujita and J. Matsui: Recent changes in tourism in Japan in terms of the trends in tourist accommodations.
(2) K. Nomoto: Changes in transportation systems in the San'in Region after the World War II, and the transformation of tourist areas
(3) A. Tanno: Trends and problems of tourism and recreation along coastal areas—a case study in the Shima and Nansei Region in Mie Prefecture
(4) Y. Mizoo: Changes in tourist activities and locational changes of tourist areas caused by the provision of high-speed transportation networks
(5) T. Tokuhisa: International tourism in Japan—trends in the behaviors of foreign tourists in Japan
(6) J. Yamamura: Development of Whistler Resort in British Columbia, Canada, and environmental conservation
Many questions and opinions were raised from the floor, mainly concerning: 1) the nature of tourism, 2) the role of transportation and private railway companies played in the development of tourism, 3) competition among different tourist areas and within the same tourist area, 4) the influence of tourism development on the environment, 5) environmental conservation in tourist areas, 6) infrastructures for tourism, and 7) foreign tourists in Japan.

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