In the hydrological cycle over arid region, playas are often the end of extensive internal drainage systems. The soil of the playa is characterized by its fine texture and high salinity. This paper presents a case study of Arrow Lake, Western Australia, and discusses the water loss function of the playa from the aspect of the peculiarity of water dynamics derived from the unique soil properties of the playa. The results of micrometeorological observations and water quality analysis (including stable isotopic analysis) of the soil water showed two peculiarities in the characteristics of evaporation and soil moisture movement. One is that the change in the phase of moisture transport from liquid to vapor occurred gradually above the bottom boundary of the dry surface layer (DSL) due to the fine texture of the soil, and the other is that the reduction in relative humidity in the DSL was enhanced by high salinity. The former gives the playa sustainability in the water loss process, but the latter acts to reduce the water loss to some extent.

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The development of transportation changes the cost space (a map drawn on the basis of traveling cost) as well as the time space (a map drawn on the basis of traveling time). Therefore it is neces-sary to consider changes in both when we study the impact of transportation developments. Review-ing previous geographical studies on this subject, however, few treated time- and cost-spaces at the same time.
In this paper, we describe the changes in time-and cost-space configurations in the Chugoku and Shi-koku regions with the development of transportation using multidimensional scaling analysis (MDS).
The results are summarized as follows:
1. The time-space configuration of the Chugoku and Shikoku regions has shrunk by 40% since 1970 with the construction of the Honshu-Shikoku Bridge and expressways in this region. The construc-tion of the Chugoku Expressway, among other things, has made a great contribution to the shrink-age of the time-space of the Chugoku region in the east and west directions. On the other hand, the construction of the Honshu-Shikoku Bridge, although called “the project of the century, ” has resulted in limited changes in the time-space configuration, which have occurred only in the region near the bridge.
2. The cost-space configuration of the Chugoku and Shikoku regions shrunk by less than 10% during the same period because a great part of the time reduction, gained by the completion of the Honshu-Shikoku Bridge and expressways in this region, has been offset by their fares. This does not necessar-ily mean that their construction has not improved the transportation conditions in this region, but the addition of new routes, which are faster than the former ones, without any additional payment must enhance the opportunity of the region for choosing alternative routes.
3. The Seto Inland Sea functions in both time-and cost-spaces as a major friction of distance in travel-ing between the Chugoku and Shikoku regions, and that friction is greater in cost-space than in time-space.
4. The INDSCAL method has been used to reproduce the common space in order to observe systemati-cally the changes in time-and cost-spaces brought about by the development of transportation. As a result, the changes in both spaces could be successfully represented in the common space. This means that these changes can be represented by the expansion and contraction of two dimensions of the common space.
5. Our conclusion is that the development of transportation in a region may cause great differences between the changes in time-and cost-spaces of the region. Therefore cost-space and time-space should be taken into account simultaneously in order to understand the changes in transportation conditions caused by the development of transportation.

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The optimal location of the representative point is discussed in relation to the estimation accuracy of the point-in-polygon interpolation method. The point-in-polygon interpolation is an areal interpola-tion method that is most frequently used in geography and GIS. This method implicitly assumes that all points are located on the representative points, and thus it yields an estimation error if the assump-tion does not hold. The accuracy of estimated data depends heavily on the location of the representa-tive point. Hence this paper analyzes the relationship between estimation accuracy and the location of the representative point, and discusses the optimal location of the representative point which mini-mizes the estimation error of the point-in-polygon method. The point distribution and the surface were investigated and it was found in both cases that the geometrical (spatial) median of the distribu-tion is the optimal location of the representative point. A numerical examination was performed on the basis of the analytical study. The results showed that the estimation accuracy given by the geomet-rical median is significantly higher than that given by the centroid when the surface distribution has a strongly concentrated form. On the other hand, these two locations yield similar accuracy of estima-tion if the surface distribution is rather smooth. These results and the fact that the geometrical me-dian cannot be easily computed suggest that in practice the geometrical median and the centroid should be chosen based on the surface distribution.

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Fossil diatom and phytolith results with a dozen ¹⁴C datings, and investigation into the stratigra-phy and sedimentary facies of borehole cores from the Kazo Lowland, central Kanto Plain, were used to reconstruct the Holocene environmental history.
The Pleistocene uplands had been dissected by narrow valleys before ca. 30, 000 years ago. From the Last Glacial maximum to the early Holocene, Phragmites swamps developed in these valleys.
The Jomon transgression caused the subsequent maximum stable sea level in the Kazo Lowland ca. 7, 000 years ago. Because marine areas invaded the valleys, inner bays were formed and the ma-rine flats expanded gradually. After ca. 5, 300 years ago, brackish environments were dominant be-cause of regression and increase in fluvial activity. After ca. 3, 500 years ago, the brackish flats were transformed into river mouths or down stream river stretches due to successive sedimentation of fluvial deposits.
After ca. 2, 000 years ago, the valleys were filled and flood plains were formed. Fluvial deposits began to spread over Pleistocene uplands rapidly ca. 1, 500 years ago. Large natural levees have been developed, covering a wide area.

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An active fault system extends for about 200 kilometers along the Median Tectonic Line (MTL) in Shikoku, Southwest Japan. Along this fault system, previous studies recognized a 10-km-long gap in the surface trace in the eastern part of the Matsuyama Plain. The gap is the largest so far found in Shi-koku. The authors newly identified very distinct strands of active faults in this gap by means of inter-pretation of high-resolution vertical aerial photographs and field work. The faults are called the Shige-nobu fault and the Shigenobu-kita fault. This paper aims: l) to depict the fault topography of the Shige-nobu and Shigenobu-kita faults; and 2) to examine the rupture history based on trench excavation across the western part of the Shigenobu fault at Takai, Matsuyama City. The results are summa-rized as follows:
(1) The trace of Shigenobu fault extends straight from Shitsukawa, Shigenobu Town, to Takai, Matsuyama City. The strike of the fault is N 75 to 85 degrees E. Alluvial fan surfaces are offset by this fault, and a clear fault scarplet is recognized continuously. The apparent vertical offset indicated by the height of the fault scarplet is 0.4 to 2.7 meters.
The Shigenobu-kita fault runs about 200 meters to the north of the Shigenobu fault. This fault, lo-cated on the margins of the plain, extends at least for 2 kilometers from Hommura to Ushibuchi, Shige-nobu Town. The M and M2 surfaces are deformed by this fault, but the L2 surface is not displaced.
(2) Distinct evidence of right-lateral movement is continually discernible along the Shigenobu fault. Several abandoned streams, located on the L2 surface and the L3 surface, are offset by 1.9 to 4 meters and pressure ridges occur on the northern side of the fault scarplet. The southern side of the Shigenobu fault is downthrown consistently.
(3) Active faults appear in a trench wall across the fault scarplet. These faults with shear plane in the trench are called F-1, F-2, and F-3. While F-2 and F-3 show no lateral offset, F-1 shows a compo-nent of lateral displacement. Therefore F-1 appears to be the main fault of the Shigenobu fault.
(4) The strike of F-1 is N75 to 85 degrees E, and the general dip is 85 to 90 degrees S. All horizons of the alluvial deposits in the trench are displaced by the main fault and are downthrown to the south.
(5) It is apparent that at least one faulting event of the Shigenobu fault occurred in the past 5, 550 years.

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