Wind erosion observed in the Kitakami Highlands has been caused by severe weather condition and deforestation. Though strong west wind in winter and solifluction in spring are known as the major physical factors of erosion, it is difficult to evaluate their effects quantitatively. This paper proposes to use a directional openess index and an averaged direct solar irradiation in addition to elevation to explain probabilities of wind erosion occurrence, and demonstrates the dominance of these factors over simple topographical factors such as slope and aspect. Generalized linear models with cross effects were applied to a dataset derived from digital elevation models and vegetation maps. The effect of deforestration on wind erosion was also analysed.

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The purpose of this paper is to analyze the damaged state of forest by a typhoon and its recovery using GIS. Digital ortho-photographs, made by a GIS application were analyzed. The result shows that multiple layer operation between digital ortho-photographs and various thematic maps was effective in explaining the state of typhoon damaged forest. The recovery from typhoon-damage was also examined in relation to 50m buffer zones from forest road. The result shows that the location of forest roads had significant influence on damaged forest recovery.

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This paper analyzed the perception of an angle between crossing roads. Experiments were performed where subjects were asked subjects to draw figures of intersections visualized on a computer display as computer-graphics. From the experiments, the following results were obtained: 1) perception of an angle is affected by its perspective angle shown on the display, 2) the difference between the true and perceived angles increases with that between the true and perspec-tive angles, 3) the variation of perceived angles among subjects increases with the difference between the true and perspective angles.

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In this paper, we discuss the disaster response support system developed through experience with disaster and recovery support activities obtained as a result of the Great Hanshin-Awaji Earthquake Disaster. The information systems to be used in times of disaster must have the following three features: 1) continuity between normal times and times of emergency, 2) decentralized independence, and 3) integration of spatial and temporal information. To actualize these features, we have developed DiMSIS, as a prototype of a spatial temporal information system. The DiMSIS has a data structure without explicit topological relation among objects and the topological relation is generalized for each query in real time. This concept is far superior for constructing a decentralized system. It can easily integrate spatial and temporal information. Finally, we present effective examples of information processing in normal times and times of emergency to demonstrate the validity of the proposed system.

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The purpose of this paper is to clarify the spatial structure in Okinawa Island in terms of accessibility to medical opportunities. Through the analyses of accessibility using network analysis in ARC/INFO, it was found that the spatial structure in Okinawa Island is considered as a system of concentric zone structures. The spatial structure of accessibility to medical opportunities in Okinawa Island changes according to the marginal distance. If the marginal distance is 5 minutes, the spatial structure in Okinawa Island consists of many concentric zones with the centre in Naha, Okinawa city, Nago, etc.. In case of 15 minutes, the spatial structure consists of two concentric zones with the centre in Naha-Okinawa City and Nago. In case of 30 minutes, the spatial structure consists of only one concentric zone with the centre in Naha.

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This paper deals with a questionnaire to urban sections of municipalities in Japan which have GIS. This study aims to make clear the condition of GIS for urban planning in municipalities, and to offer some suggestions to promote the introduction of GIS to the urban section of municipalities. The result shows that there are some aims of using GIS for urban planning section, and it is necessary for realizing advanced use of GIS in urban planning field to develop the GIS which is easi-er for operating and to rearrange city information properly from point of urban planning view.

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This paper introduces some GIS studies in Poland based on information collected at five Polish organizations in October 1998. Despite social and economical differences from western developed counties, many Polish geographers began applying GIS to environmental studies during the last several years with some very fruitful outcomes. GIS will do much for the progress of geographical research in Poland.

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