There are characteristic patterns in the airflow system which relate to distributions of surface climatic elements. Japanese climate has been studied using the airflow patterns (Jacobs, 1946; Maejima, '1954). The airflow patterns were set up from the gradient wind direction. But, the gradient wind direction might not be used, especially in the large area. The airflow system spreads over the Japanese Islands. By classifying the airflow system, the macro-scale airflow patterns in the Japanese Islands are set up.
From Hokkaido to Kyushu, strong winds blow in winter and spring. Then the area is chosen to set up the macro-scale airflow patterns in the Japanese Islands (Fig, 1). In the daytime wind is stronger than in the night, so the observed values of wind are representative for time and space. The airflow patterns are represented by the daily 15 JST wind direction and speed in 1973.
The surface wind distribution was usually classified subjectively. But, if the area was more extensive, the subjective classification was more difficult. While, cluster anaysis was adopted to classify the area (McBoyle, 1971). The cluster analysis, one of the objective methods, can evaluate the difference between the distributions even if they can not be classified subjectively. Then, the surface wind distributions are classified by cluster analysis in this study.
The distance index of two surface wind maps is defined from the sums of wind difference at the same station between them. Also, the revolved definition of distance, the distance between the new cluster and the former cluster, is calculated by the group average method in this ` study. The process of the cluster analysis and the relation between clusters are expressed on dendrogram (Fig. 2). On the dendrogram, the cluster sometimes will not be combined in spite of the increase of distance. Each cluster is well unified on that occasion. The distance index 2. 2 corresponds to that case. There are 12 reasonable clusters. They are grouped into 3 principal clusters.
The macro-scale airflow patterns are set up from the 12 clusters. The resultant winds of them are effective expression of surface airflow patterns (Fig. 3). Characteristics of them are as follows. Southerly winds (a₁_??_a₄ type): a₁, sea breezes blow all over the Japanese Islands; a₂, southwesterly to west-southwesterly strong winds blow all over the Japanese Islands; a₃, sea breezes blow in the Japanese Islands except for the Pacific Ocean side of Hokkaido and Tohoku District; a₄, southwesterly winds blow in southwestern Japan. Northeasterly winds (b₁_??_b₃ type): b₁, easterly-winds-like sea breezes blow on the Pacific Ocean side, while roughly northerly winds blow on the Japan Sea side of southwestern Japan b₂, northeasterly winds blow in southwestern Japan; b₃, northeasterly to northerly winds blow in central and southwestern . Japan. Westerly winds (c₁-c₅ type): c₁, westerly winds blow all over the Japanese Islands; c₂, westerly strong winds blow in the Japanese Islands except for Hokkaido; c₃, northerly winds blow all over the Japanese Islands; c₄, roughly westerly winds blow all over the Japanese Islands; c₅, roughly northwesterly winds blow in northeastern Japan, while roughly northerly winds blow in southwestern Japan.
To clarify the daily macro-scale airflow patterns in other years, discriminant analysis is used. It classifies the unknown sample according to the established type. Then, the macro-scale airflow patterns from 1968 to 1977, are clarified. The annual variation of each airflow pattern's frequency is exhibited (Fig. 4). Southerly winds (a₁_??_ a₄ type) occur in summer. Northeasterly winds (b₁_??_b₈ type) occur mainly in spring and autumn.

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Rurals areas of the eastern Kanto Plain, in which the study area is situated, were characterized until recently by traditional farming based on such cereals as rice and wheat, and sweet potatoes and industrial crops. But, in the past twenty years, these areas have greatly changed their character through the development of highly commercial agriculture, such as vegetable growing, flower growing, and large-scale pig raising, on the one hand, and the expansion of part-time farming on the other. Farms in outer suburban areas around large cities are composed of two distinct groups. One group of farms manages to earn a sufficient income from farming activities, generally by increasing the agricultural intensity of their farms. In the other group of farms, high dependence upon non-agricultural income brings about the contraction of farm management. In this study, the author focuses his attention on the former group of farms, that is, agriculturally viable farms. In fact, these viable farms exert great efforts at all times to make their farm management the most profitable, taking into account the size of their cultivated land and labor force, and other conditions. In order to grasp the regional characteristics of an agricultural area, it is therefore very important to examine the contents of farm management of viable farms and the conditions of the formation of these farms This approach may be particularly effective in outer suburban areas, where various types of viable farming exist and change rapidly their farm management.
Three agricultural communities (Tozaki, Omae, and Uchikamo) were taken as the study area. Viable farms were defined as farms with male regular farm workers. Operationally, the author adopted three conditions : (1) farms dependent mainly upon agricultural income, (2) farms having at least one male regular farm worker under sixty-five years of age, and (3) the male regular farm worker is not engaged in non-agricultural jobs more than thirty days. Farms which conform to all of these three conditions are considered as viable farms.
In 1980, there exist eighty-four viable farms in the three communities This accounts for 56 percent of the total number of farms. These viable farms were classified in terms of a leading sector of production in agricultural income. Lotus root cultivation is practiced as a leading sector in fifty-seven viable farms. Especially in Tozaki and Omae, fifty-two out of fifty-six viable farms cultivate lotus roots as a major product. In fact, the study area forms a part of a leading producing area of lotus roots in Japan, There are, however, few farms which gain their agricultural income solely from lotus root cultivation. The effective utilization of upland fields has an important meaning in these viable farms because their cultivated land is composed of the combination between paddy fields in the alluvial plain and upland fields in the diluvial upland. Therefore, by the second sector in agricultural income, they were further divided into several subtypes (lotus roots with crops of ordinary upland fields, lotus roots with sericulture, and lotus roots with Japanese pears, for example). On the other hand, in Uchikamo, upland fields occupy the large part of cultivated area, where the leading sector of production of each viable farm is relatively dispersed among various sectors, such as flowers in green houses and pig raising.
As the first step of analysis, the author examined each of the viable farming types succesively. Also, he investigated the conditions which influenced the differentiation of the viable farming types and, at the same time, the general characteristics which were commonly observed in all types. After that, the regional character of the viable farming in the study area were discussed.
In this way, we could recognize in the viable farming of the study area the following characteristics, which seemed generally applicable to the outer suburban areas of large cities.

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Recently, Moriyama (1977, 1978) and Moriyama and Asai (1980) suggested that the grain size distributions of lower alluvial plain sediments and of river bed materials were strongly affected by the size characteristics of rock-forming minerals and weathered materials in the upper drainage basin of the Yahagi River composed of granitic rocks. At the same time, it was also pointed out that hydraulic conditions in sediment-transportation and accumulation acted to vary the mixing proportions of normally distributed component populations of sediments. These suggestions are very interesting, but are still presumptive, and are not proved actually. In order to prove these suggestions, it is neccessary to make clear the manners of sediment transport occurred on the hill slope in source regions of drainage basin. Then, the writers analysed the grain size distributions of the weathered materials of granitic rocks which were supplied to river bed, and of the river sands which were considered as bed load, and of the suspended materials during floods in the source regions. In addition, they made clear how the grain size distributions of suspended materials changed in the proportions of component populations as hydraulic conditions. The writers selected two small basins different in size characteristics of rock minerals. One is the Mitachi River composed of the Inagawa Granite (coarser grained granite) and the other is the Shinpuku ji River of the Busetsu Granite (finer grained granite) . Both kinds of granitic rocks are the most widely distributed in the Yahagi River catchment basin. Samples of weathered materials were collected from B and C holizons of hill slope soil at each point. As for suspended materials, turbid surface water were scooped up every thirty minutes at the end of the small basins. Sediment grains coarser than 3.5 phi were analysed by the method of mechanical sieving (1/4 interval), and finer silt and clay particles were analysed by the photoextinction sedimentation method (Moriyama, 1976, 1980) .
The results of analyses are shown in Figs. 3, 4, 6 and 7. First of all, both of the histograms of weathered materials of grainitic rocks and of river sands in the Mitachi River basin have three peaks around -2 phi, 0 phi, and 2 phi, respectively. Namely, peak size of each sub-population is coincided with each other between the weathered materials and the river sands. In the Shinpuku ji basin, both histograms of weathered materials and of river sands have two peaks around 0 phi and 2 phi, and the peak positions are also mostly the same. These facts are explained that the weathered materials of granitic rocks were carried and accumulated on river bed during the flood by being preserved their size characteristics.
Next, the weathered materials of the Mitachi have several peaks around -2 phi, 0 phi, 2 phi and 5 to 6 phi (the peak of 3 phi also can be seen), and the suspended materials have the marked peaks around 2 phi, 3 phi and 5 to 6 phi. The peak positions recognized in both materials are similar to each other. On the other hand, the histograms of weathered materials in the Shinpuku ji have two peaks around 5 to 6 phi and 6 to 7 phi in clay population, and these peaks coincide considerably in position with those of clay populations of suspended materials. These facts suggest that the weathered materials outflow as suspension or wash load by being preserved their peak positions, and that the hydraulic condition has relation to the change of mixing proportions of sub-populations.
The mixing proportions of 2 phi populations of river sands decrease gradually from the upper reach to the lower one in both rivers, while in the size distribution of suspended materials, the mixing proportions of 3 phi populations increase, then those of 2 phi populations increase in turn as discharge increases.

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On a clear and calm night, a cold air lake is formed in such a basin as Sugadaira, mainly by radiative cooling. In order to identify the formation process of a cold air lake, we made observations from the evening of 8, May, 1981, at the Sugadaira basin in Nagano Prefecture. We used seventeen sets of the self recording bimetal thermometers to observe the distribution of temperature in the basin. Vertical temperature distributions were observed by utilizing the captive baloons with thermistor thermometers. These baloons were moved up to 100 meters height above the ground three times in this night at three points, two of these were located on the northeast slope of Mt. Omatsu and the other one was located at the bottom of the basin. Wind directions and velocities were also recorded on the same slope (Fig. 1).
By these observations, we could see the horizontal and vertical temperature distributions of the cold air lake and their changes with time. The characteristic process of the cold air lake formation was as follows: After sunset, surface air temperature began to fall rapidly, especially at the bottom of the basin. But a zone of rising temperature appeared on the slope of Mt. Omatsu around 9 p. m. in the night (Fig. 2). And the change in temperature which were observed on the slope and the bottom of the basin showed very different patterns with each other. At the bottom of the basin, temperature has gradually fallen. On the other hand, temperature on the slope showed repeated rise and fall. Thus, the air on the slope was not so cooled as it is at the bottom of the basin (Fig. 3). In Fig. 4, it was shown that air temperature above the slope was rising during RUN 2 and RUN 3. It is suggested that the draining down of the cold surface layer air mass has occurred during these observations. At this time, the temperature in the cold air lake

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