Cryptomeria japonica and Thujopsis dolabrata var. hondai have similar life-form and make the cooltemperate coniferous forest in Japan. It was thought that these two species had different process of spread of distribution in the postglacial time. During the postglacial period in northeast Japan, C. japonica migrated from south to northeast and Th. dolabrata var. hondai developed from ice age refugia scattered there.
The purpose of the present paper is to explain the difference of behavior between the two, based on the relation between the present distribution of habitat and climatic condition. The results are follows.
(1) C. Japonica is restricted in Honshu under the climate of Japan Sea type and Th. dolabrata var. hondai reaches to southern Hokkaido under climate of Japan Sea and Pacific-Japan Sea transitional type; annual water surplus by Thornthwaite's method is over 800mm for C. Japonica and under 1, 400mm for Th. dolabrata var. hondai; minimum and maximum value of total winter (December, January and February) precipitation is 300mm and 900mm for C. japonica and 150mm and 600mm for Th. dolabrata var. hondai, respectively.
(2) The lower limit of thermal condition for Th. dolabrata var. hondai is closely related with the condition of hydro-climate. It can reach to coldest condition about 25°C Month of warmth index under 700mm of the annual water surplus or 200mm-300mm of total winter precipitation. Th. dolabrata var. hondai grows in the mountain and subalpine zone with Tuga diversifolia, Abies mariesii and others and even in alpine zone where it is stunted conspicuously and flourishes in the shrub and herb layers. For C. Japonica, however, the properties as seen for Th. dolabrata var. hondai can not be recognized.
(3) If the lowering mean annual temperature was 7°C at the maximum of the last glaciation, the altitude of 25°C Month warmth index is estimated about 500m above the sea level in Tohoku and about 200m a. s. l. in the Oshima peninsula, southern Hokkaido. Considering the present behavior of Th. dolabrata var. hondai and C. japonica, it is able to interpret that the Th. dolabrata var. hondai contracted into scattered refuges in Tohoku and southern Hokkaido under the condition of less winter precipitation, although C. japonica had not been able to grow in southern Hokkaido during the full glacial interval.

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The Ota River Lowland is located in the middle part of the Tokai region, Central Japan, extending about 20km from north to south and 12km from east to west. The Lowland is mainly composed of muddy deposits which are carried by the Ota River.
The purpose of this paper is to clarify the formative process of the Ota River Lowland. This study is based on the analysis of data from boring, the results of radiocarbon dating, the distribution of archaeological remains, the distribution of the Jori grid-system, and old maps.
The sediments of the Ota River Lowland are divided into six units: the basal gravel layer (BG), the lower silt and clay layer (LC), the middle sand layer (MS), the middle silt and clay layer (MC), the upper sand layer (US), and the upper silt and clay layer (UC). The basal gravel layer is considered to represent the river bed gravel in the Last Glacial Age. The lower silt and clay layer was deposited under a low salinity environment and is divided into silt and clay. The silt layer contains a small quantity of shell and the clay layer contains a little humus. The middle sand layer is contrasted to the Holocene Basal Gravel Bed (HBG). The HBG was named by Endo et al. (1982), and indicates the basal gravel layer of the Holocene deposits. The middle silt and clay layer contains a large quantity of shell which shows that the depositional environment was affected greatly by marine water. The upper sand layer is the marine deposits, containing a little biotite, pyrite and magnetite, and is supposed to represent the deposit which is carried by the Tenryu River. The upper silt and clay layer is composed of humic silt and clay, and is considered to have been deposited in a sedimentary environment of backmarsh.
In conclusion, the geomorphic development of the Ota River Lowland during the latest Pleistocene to the present is summarized as follows.
1) In the latest Pleistocene, the Ota River Lowland was developed in the former fluvial valley formed by the lowest sea level of the Last Glacial Age. Afterward, the former fluvial valley was drowned by transgression, and was filled with silt and clay (about 20, 000-10, 000 years ago).
2) About 10, 000 years ago, the sea level dropped because of the cold climate episode and the fluvial sand accumulated in the drowned valley again.
3) In the early Holocene, the sea level rose rapidly. As a result, the Ota River Lowland became a bay. After the culmination of the post glacial sea level rise, the sea level remained stable. At this time, the sediments of the Tenryu River drifted into the bay of the Ota River Lowland, and closed the bay mouth (about 10, 000-6, 000 years ago).
4) The closed bay became a brackish, swampy lagoon (about 6, 000-1, 900 years ago).
5) In the late Yayoi period, the sea level rose again and the sea water flowed into the middle part of the Ota River Lowland (about 1, 900-1, 700 years ago).
6) By the seventh century, the Jori grid-system was enforced and the sea level dropped again. However, the water area was left in the southern part of the Ota River Lowland as before (about 1, 700-1, 300 years ago).
7) The water area disappeared owing to the Hoei earthquake in 1707 (about 300 years ago).

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As a result of the growth of modern industries since 1937, Hachinohe developed rapidly and became one of the industrial cities in Tohoku. The 1990 census recorded about 241, 000 inhabitants. Until the advent of industrialization, however, Hachinohe city mainly consisted of five historic cores: Hachinohe, which originated from a small castle town during the Edo period, Konakano, Minato, Shirogane and Same, which were the fishing and trade ports at distances of one to five kilometers east of Hachinohe. Its total population together with the port towns in 1935 was about 62, 000.
The purpose of this paper is to explain the changes of urban land use pattern of Hachinohe during the pre-industrial stage, between the Edo period and 1936, and the economic forces which operated in shaping the land use pattern.
By the mid-1930s, shopping streets, mixed commercial and workshop areas and residential areas were formed in and around each historic core and the zones of dispersion tended ultimately to coalesce into a single urban complex. These changes were due to the economic advances during the period since 1920. Hachinohe had good fortune not only as a fishing port but as a shipping port for ores carried from its hinterlands, and increased the industrial outputs of marine-products and cement. Among these activities fishery has exerted the most important influence on the emergent land use pattern, because Hachinohe has not replaced a mercantile city by an industrial one.

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Based on detailed observation of slope form and regolith characteristics, this paper discusses the spatial changes of slope processes and their differences in intensity and frequency on both segments seperated by the lower convex break of slope in a small watershed in the Omatsuzawa Hills. The detailed observation of slope morphology and grain-size analysis of regolith reveal that slope processes are prevalent both on the upper and that lower slope segments in the recent past and more frequent and intensive slope processes were prevailed on the lower slope segment. The lower convex break of slope designated as the Postglacial Dissection Front is a result of more active erosion on the segment lower than the break, but it does not mean non-occurrences of slope processes on the segment upper than the break.

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