For the first time in the long history of rice farming in Japan, totally new conditions have arisen. Increasing the production of rice has been restricted to prevent overproduction since 1970, while consumer demands for the deregulation of government policy and calls for excellent quality rice have increased. The purpose of this paper is to outline the reorganizing process of non-glutinous rice varieties in the past quarter century (1970-1995) in the Northeast Japan under the new conditions mentioned above and to consider the geographical meaning of this change.
We can recognize three periods in which the acreage of dominant varieties was very changeable: the first period in the early 1970s, the second period in the late 1970s to early 1980s, and the third period in the late 1980s to early 1990s. The former two periods were basically characterized as periods of trial and error. Although excellent varieties of high quality rice diffused in part, attention was focused high yield varieties using mechanized farming. The third period is characterized by new excellent rice varieties drastically replacing the old except in cold, marginal rice regions in Hokkaido and mountainous Tohoku.
Geographically, we can point out two important things. Firstly the transformation from high-yield rice culture to excellent quality rice for food developed early in southern Tohoku. After that, it gradually diffused to the northern Tohoku and central Hokkaido districts. This is compared to the process of the diffusion of rice as a staple in cold weather regions in the past. Viewed from a regional standpoint, there are relatively many kinds of excellent varieties in Tohoku and a few in the Hokkaido district. This difference occurred because of cold weather conditions.
Secondly, the development of the new varieties mentioned above is very important —in particular “Kirara 397” in Hokkaido, “Akitakomachi” and “Hitomebore” in Tohoku— because they did not depend on “Sasanishiki” originating in Miyagi prefecture but were based on “Koshihikari” which is ranked as the most excellent quality (the highest-priced) variety in Japan today. In addition, these new varieties have not only an excellent taste for consumers but a welcome resistance to cool-summer damage.
In conclusion, Northeast Japan's rice farming generally will be sustained in the future, at least for the level of rice varieties, although there are still parts of the region that can not adopt new varieties.

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The purpose of this paper is to discuss a process of channel diversion and the age of divide in valley forming by studying fluvial landform units.
Two divides in valley described in this paper are situated at Kunizakai and Shindohno in the Nosaka Mountains, Southwest Japan. River terraces in the study area are divided into three surfaces. H surface group including plural surfaces formed before the Last Glacial stage. L1 surface and L2 surface formed in the Last Glacial stage, the former is distributed widely and the latter is preserved in small patches. L1 terrace deposits are divided into the lower part which is composed of gravel, and the upper part is done of silty sand including AT tephra (22-25kyBP).
At Kunizakai divide in valley, R. Goi and R. Chinai face each other, the former flows towards the Japan Sea and the latter towards Lake Biwa. At the upstream of R. Goi, the lower part of L1 terrace deposits includes boulders of the Tanba Group which is not existed in the present basin. It shows the boulders are transported from the upper course of R. Chinai in which the Tanba Group is distributed. This is the evidence that the water of upper course of R. Chinai had flowed into R. Goi through Kunizakai.
At deposition of the upper part of L1 terrace deposits, the water at Kunizakai flowed southwards into the lower course of R. Chinai because the drainage became poor and valley filling progressed. Kunizakai divide in valley formed through this process and its formation age is during the accumulation of the upper part of L1 terrace deposits.
At Shindohno divide in valley, R. Asoh and R. Oh face each other. The former flows towards the Japan Sea and the latter towards Lake Biwa. There is no evidence that the channel diversion occurred in the geomorphic feature, the profiles and the gravel composition of L1 and L2 terraces. These indicate that Shindohno divide in valley formed before the Last glacial stage.

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The present study deals with climatic condition in the Abukuma limestone cave, Northeast Japan, based on the results of micro-meteorological observations carried out in the summer of 1996 and the winter of 1997.
In the closed upper level of the cave, wind velocity were almost 0m/s in the summer of 1996 and in the winter of 1997. Breeze blew occasionally from the entrance of the lower level and the exit of the middle level in the summer. In most cases wind blew into the lower level, but a part of it blew from the exit of the middle level in winter. At the lower and middle level, air temperature and humidity were lower in the winter than the summer, because of the effect of air streams from outside into the cave. On the other hand, higher air temperature and higher carbon dioxide concentration appeared at the closed upper level of the cave in the summer of 1996 and in the winter of 1997. Air temperature increased in accordance with the increase number of visitors in the cave. Daily maximum and minimum air temperature increase in mid-August because of the largest number of visitors. After mid-August, it began to decrease gradually. In winter, air temperature rose by visitors at the only upper level. In conclusion, at the upper level, the relations between the daily numbers of tourists and air temperature, the cumulative number of tourists and carbon dioxide concentration showed a significant correlation.

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The Tsubonuma Fault and the Enda Fault, which strike NE to ENE and dip NW, are referred to as active reverse faults. This paper aims to describe an outcrop which is located in the south of Sendai City along the Tsubonuma Fault, and to obtain the data on faulting. At this locality, the Lower Miocene pyroclastic rock (Takadate Formation) thrusts over the Pleistocene tephra sequence. Following four marker tephra layers which are Middle Pleistocene in age are discernible in the sequence on the basis of their lithofacies and the chemical composition of ferromagnetic minerals: Tsubonuma Lithic Fragments Layer (Tblf), Tsubonuma-2 Pumice Layer (TbP2), Tsubonuma-3 Pumice Layer (TbP3), and Tsubonuma-4 Pumice Layer (TbP4), in ascending order. It becomes obvious that the Tsubonuma Fault moved after the deposition of TbP4 which is the uppermost Middle Pleistocene marker tephra in the environs of Sendai. Such as the net slip and the beginning of the faulting should be further confirmed in detail, in order to clarify the trend of neotectonics in the outer zone of Northeast Japan Arc.

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