A series of experiments was performed to determine the effect of water discharge and sand supply on the slope of a “flood plain” in an equilibrium state. A slope that was formed by deposition of uniform sands, 0.5_??_1.0 mm in diameter, was measured when the equi-librium state appeared in a sufficiently broad flume (57 cm) under a fixed condition of discharge and sand supply. Experiments were made on 23 combinations of discharge and sand supply (Table 1).
Within the limits of our experiments, the slope is a linear function of sand supply and/or the ratio of sand supply to discharge when discharge is constant (Fig. 5). When the ratio of sand supply to discharge is constant, the relation between the slope and discharge is nearly linear on a log-log scale (Fig. 7).
The ratio of sand discharge to sand supply was measured as a mark of the equilibrium state under the fixed condition. This ratio fluctuates randomly around the mean value 1.0 with time, even though operation time is longer than enough to appearance of the equilibrium state (Fig. 3). The equilibrium state, therefore, should be dealt with as a stochastic one determined by some semidependent variables, for example, velocity, depth and width of running water, roughness of sand bed, etc., which change spontaneously even under a fixed external condition.

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To meet with the ever increasing needs for betterr facilities and more areas at the tourist or recreational resorts, the private sectors and also the government are investing compara- tively huge amount of capitals and energy in this field.
To effect most desirable development of tourist resorts and its facilities, however, it has become more important to study the method to evaluate the values of tourist resources. Development of a new tourist resort will have to be planned on the basis of preserving precious resources, formation of attractive sightseeing routes, estimation of future tourists traffic. All these researches and planning works require more adequate and scientific evaluation of tourist resources. We consider, however, that the systematic evaluation technique required for above purpose are not yet sufficiently studied in our country.
In our study, we aimed at evaluating the proper value of the tourist resources. Whether the resources are located within easy access for a large city or not, did not give influence in our evaluation. Our evaluation has been made mainly from a touristic, not recreational, point of view. These resources are normally grouped into two categories, i.e., natural resources and cultural resources. They are objects created during enormous span of time or through successive generations.
Our study on the captioned subject started from selecting 392 tourist resources out of various data. The 392 resources are well balanced in the way of areal distribution, class and variety.
For instance, included in a variety of resources are, 27 mountains, 23 plateaus, 25 rocks, 25 rivers and valleys, 16 waterfalls, 25 lakes, 27 islands, 24 plants, 27 mountain passes and observation spots, 27 coasts and promontories, 27 shrines and temples, 25 castles, 23 gardens and parks, 21 historical spots, 23 local scenery, 27 festivals. Animal resources are excluded from the list, because of uncertainty in seeing them.
Then we have selected 14 scales to evaluate tourist, resources as follows: size, texture, history, color, light and darkness, variety, density, odor, sound, composition, shape, superiority, ranking, locality. The scale of evaluation must be applicable to all resources. For instance, the color can be one of the scales to evaluate such varied resources as mountains, plants, shrines, etc.
Next, we have rated 392 resources against above 14 scales (Table 2), and have computed the correlation between scales. Further, we have facorized its matrix. As the result, five scales have been extracted as most appropriate factors. They are ranking, composition, size, color and locality. These five factors accounted for 50.32% of the total variance (Table 3). On the other hand, we have asked five specialists to grade 392 tourist resources into four classes, i.e., SA (special A), A, P and C, according to the following criteria:
SA Class………International level resources
A Class……… Country-wide level resources
B Class………Regional level resources
C Class……… Prefectural level resources
This grading can be called “general evaluation”. Five specialists include researchers in tourism study and travel writers.
Finally, using “general evaluation” as criterion valuable, and also the numeral value of 392 resources rated on five scales as predictor valuables, we applied the discriminant method of Quantification Theory II introduced by Dr. C. Hayashi. The amount of discription of these five evaluational scales has proved to be placed in the following order: 1) size 2) composition 3) locality 4) ranking 5) color. The first three factors are especially persuasive (Table 4). It has been found that the efficiency of discriminant between 4 classes under these five scales is very high within the limit of 79_??_81% each class (Fig. 3).

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Among various types of bed forms in alluvial channels, many researchers paid much effort to clarity the condition of the formation of bars, since the hydraulic characteristics of natural streams cannot be fully understood without a knowledge of basic principles that govern the formation of bars. To date, however, there has been no satisfactory explanation for the formation of various types of bars.
Through the flume experiments, the author recognized 4 types of bed configuration de-fined by bar development, each of which appears according to the different hydraulic regimen (Ikeda, 1973).
In this paper, the author attempts to classify the configuration of alluvial channels into these 4 types and examine the condition of bar formations, using the same parameters as in the flume experiments. The lower Omoi River, Tochigi Pref., was chosen for a study area where a detailed field observation was made along 4 reaches (from No. 1 to No. 4 in down-stream direction, Figs. 1 A, 2 B) which represent above mentioned 4 types of bed configu-rations respectively.
No. 1 reach: corresponding to Type 1; The type of multiple bars, consisting of a set of linguoid and diagonal bars, is generally regarded to be features of channels of low sinuosity, with high width-to-depth ratio and steep slope. At low flow, higher parts of each bar emerge as mid- and side-shoals, dividing the stream (Fig. 5). These bars correspond to braid bars (Allen, 1968), spool bars (Krigstrom, 1962) and channel bars (Thornbury, 1954). Figures 10, 11 and 18 show the features of similar channel configuration.
No. 2 reach: corresponding to Type 2; The type of alternate bars, consisting of diagonal bars with sharp crest lines which migrate downstream (Fig. 6). A sharp avalanche face of their downstream edge and abrupt change of talweg from one side to the other constitute a characteristic feature of this type of bed configuration. At low flow, because of the alter-nate arrangement of side shoals, alternation of riffles and pools are seen.
No. 3 reach: corrresponding to Type 3; The type of alternate bars, consisting of diagonal bars with obscure crest lines, often arises in channels of sandy bed. It resembles to type 2 in plan (Fig. 7), but relief of bars is much smaller, therefore riffles and pools do not appeareven at low flow, and talweg meanders continuously from one bank to the other.
No. 4 reach: corresponding to Type 4; No bars are formed. Although alternate de-pressions are formed at low flow even in the straight No. 4 reach (Fig. 8), the maximum relief in the bed is less than 50 cm. It is regarded, therefore, that bars are not created in such channels of gentle slope and very small width-to-depth ratio, as channels of delta plain (See also Figs. 12 & 14).
The median grain size of bed materials in the upper part of the study area is 10_??_20 mm in diameter, while at 14 km below the junction of Sugata River, it decreases suddenly to 1 mm (Fig. 2 B). And the channel slope decreases downstream in accordance with the change of grain size of bed materials mentioned above (Fig. 2 A). Further, the channel configuration of the lower Omoi River also changes downstream accordantly to the decrease of channel slope and grain size of bed materials (Figs. 3 & 4). This relation is schematically illustrated in Fig. 9.
In order to clarify the hydraulic conditions of formation for each 4 types of bed configu-ration, two parameters, U*/ U*c (flow intensity) and S•W/D (channel form index) were obtained by dimensional analysis based on similarity-law of distorted models. Here U* is shearing velocity at bed, U*c is critical shearing velocity for bed materials, S denotes slopes, and as the channel forming discharge is here approximated by the bankfull discharge, the bankfullwidth and -depth are used for W and D respectively (Table 1).

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Urban climatological studies can be historically divided into three stages: the first stage is a simple comparison of standard meteorological elements between a city and its immediate environs; the second is an investigation of the horizontal distribution of these meteorological elements in the city; and the third is an investigation of the three-dimensional aspects of the urban climate. The author, however, considers that comparative investigation of the underlying processes that produce these observed characteristics in the horizontal meteorological fields should also be very important. In this context, this study is directed towards a systematic understanding of the radiation balance of an urban environment by introducing examples obtained primarily in Canada and the United States.
The radiation balance at the earth's surface can be written as follows: Q_N=K↓-K↑+L↓-L↑ (1) where Q_N is net all-wave radiation; K↓, global solar radiation and K↑, reflected solar radiation; L↓, downward atmospheric radiation and L↑, upward terrestrial radiation. Both K↓ and L↓ are dependent on atmospheric properties whereas KI and LT are influenced by the surface. For the former, scattering and absorption of aerosols are important and for the latter, albedo (α) and emissivity (ε) of the surface are important.
Among the radiation balance components, global solar radiation has received much attention because it is the most fundamental energy for life and because it can be readily and easily monitored. Notable radiation studies in urban areas were carried out in Montreal (East, 1968), Cincinnati (Bath and Patterson, 1970) and Toronto (Yamashita, 1973). In general, the reduction of solar radiation in an urban environment is about 15_??_20% (Landsberg, 1970) but this effect on the radiation balance is unique to each city. From a climatological viewpoint, the total solar energy is more important than the energy associated with a specific wavelength, despite the fact that the physical property of radiation is dependent on wavelength (the shorter the wavelength, the larger is the attenuation of solar radiation).
A considerable amount of solar radiation, scattered by aerosol layers in the urban atmosphere, is received at the surface as diffuse sky radiation. This was verified for Toronto (Yamashita, 1973) and for Hartford (Sprigg and Reifsnyder, 1972). Hence, turbidity factor may be useful to understand the dome-shaped structure of an urban atmosphere. Not only dust content but also water vapour content over a city must be investigated because these exert considerable influences on the radiation and energy regimes. Albedo is one of the most complex element in urban climatological studies. Albedo will be increased by removal of vegetation and frequent use of light coloured materials, while, on the other hand, will be decreased by multiple reflections in urban canyons. Numerical solution of albedo for the urban canyon by Craing and Lowry (1972) appears promising.
An aerosol layer over the city absorbs solar and terrestrial radiation and then emits this energy as longwave radiation. However, this process is not easily verified because of observational difficulty and small energy involved. Significant studies were made in Cincinnati, Montreal and Los Angeles. Upward terrestrial radiation also increases in an urban area, and this tends to offset the downward atmospheric radiation. Thus, emissivity of urban surfaces should be investigated in detail.
Lettau's climatonomy helps us to investigate the shortwave radiation balance of the urban atmosphere. Figure. 6 shows such an example derived, for Metropolitan Toronto (Yamashita, 1974).

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This paper attempts to pursue how a rural community has transformed itself with the industrial development. The reclaimed community studied, which is located in oyama City of Tochigi Prefecture occupying the northern part of the Tokyo metropolitan region, was characterized by a pure rural landscape, but it has greatly added to its character some industrial aspects during the nation-wide growth of Japanese economy in the last decade.
In this paper, the author puts stress on understanding the reasons why the farmers of the reclaimed community accepted or had to accept the new location of big factories, which would give a radical conversion to their living, and the ways how they thought and conducted themselves in the process of this new location. In this point, it is generally to be thought that the farmers' attitudes toward the transformation of their community to industrialized one are strongly influenced both by the external force of industrialization and by the nature of the rural community.
There were three stages in the industrial development of oyama City from the historical point of view. The third stage, corresponding to the period of the rapid growth of Japanese economy since 1955, was quite different in quality and in pace of industrialization from the preceding stages. Also, this city was the typical one of rapidly industrialized cities in this period. So, it could be regarded as the city on which the external force of industrialization influenced in the strongest.
As for the nature of the rural community itself, the newly reclaimed community in this city had the following characteristics:
1) The farmers in this community have suffered from the low crop productivity due to the infertile land and the unseasonabiness such as a cold snap in spring and over-droughts in summer.
2) Most of the newly colonized farmers, predominating in the community, were unmarried and had less experience than the native-born farmers. Consequently, they could neither conduct effective agricultural management nor succeed in a new plantation such as peach culture. This obliged them to get deeper and deeper in debt.
3) In the community, income difference gradually appeared and became greater between the farmers having better conditions——such as ealier colonization, ownership of paddy fields and affluent experience of agriculture——and those having less favorable conditions.
4) with regard to the farmers' attitude for establishing big factories, there was a strife between people with a more or less conservative opinion and those with a more or less reformist spirit. This resulted in a situation that they were not strongly united.
Broadly speaking, all of these characteristics indicate a weakness as for the community's rural foundation. Thus, when the project that aimed to change the reclaimed land into an industrial park was offered to the farmers by municipal authorities, they were obliged to accept this project. As a result, most of them removed themselves and the reclaimed community was completely broken up.
This project of an industrial park was carried out under the leadership of the municipal authorities with the two main objects: the industrialization of oyama City and the income increase of the farmers through their removal from the reclaimed land. However, every farmer had great attachment to the land which they had reclaimed with the greatest efforts for more than ten years, and this attachment was quite strong particularly in the case of industrious farmers who had built up the foundation of agricultural management with much difficulties and also had a reformist sentiment. These industrious farmers strongly opposed to the project for the reason that the foundation of their living would be destroyed.

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