自然河川についてはレジーム公式,ないしはhydraulic geometryがあるが,実験水路については従来の実験が流量にくらべて狭い水路で行なわれてきたため,それに相当するデータが得られていない.そこで流量・給砂量と平衡勾配との関係について,基礎的データを得ることを目的として本実験を行なった.
「沖積地」ができるほど流量にくらべて幅が十分広い実験水路において,流量と給砂量を十分な時間一定に保ち,水路の中に平衡状態を出現させ,「沖積地」の勾配を測定する.このようなRUNを流量・給砂量の23組の組み合せについて行ない,流量・給砂量と「沖積地」の平衡勾配の関係を定量的にとらえた.この実験の流量と給砂量の組み縫せの範囲内では, 1) 同一流量に対して,勾配は給砂量あるいは給砂量/流量)の一次関数で表わされる(Fig. 4). 2) 同一の給砂量・流量比に対して,勾配と流量は両対数紙上でほぼ直線関係にある(Fig. 7).
十分な時間の通水を行なった後でも,短期間の測定値である排砂量,給砂量比は値1.0の周囲をランダムに変動する.もちろんその平均値は1.0に漸近する.これは開放平衡系の外部条件(ここでは流量・給砂量・粒径)を一定に保っても,系の内で流速・水深・流水幅・流路形態などが,相互に関連は保ちつつも,時間と共に自励的に変動するためである (Fig. 3).

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観光資源を適確に評価することは,観光資源の保護育成エリアの確保,魅力ある観光ルートの形成,入込み観光客の需要予測などを決めていく観光地計画上,大切な要件である.本論は論理性,汎用性,操作性の観点から,より有効な尺度を關発することによって,精度の高い観光資源の評価を確立していこうとするものである.
作業はまず392観光資源と14尺度から因子分析を行ない,5尺度を抽出した.次に,観光関係の仕事に精通している専門家による392観光資源の評価ランクを外生変数, 5尺度別の観光資源の評価を説明変数として,数量化II類の判別モデルを適用した.その結果,観光資源をランク付けする判別力の大きい尺度は,「規模」「構図」「ローカリティ」の順になり,「格付け」「色」は比較的影響力の小さい尺度あった.各ランクを判別する適中率は,いずれも79～81%の間に収まっている.

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利根川支川の思川下流部の河床形態を,砂礫堆の発達状態にもとづいて, 1) 複列砂礫堆, 2) 明瞭な前縁を有する交互砂礫堆, 3) 前縁の不明瞭な交互砂礫堆, 4) 砂礫堆が形成されていない河床という4つのタイプに大別し,それぞれの特性を他の河川の例を加えて調べた.そして河床形態の各タイプの形成条件を流れ強度U_*/U_*cと河道形状示数 3・W/Dの2つのパラメータによって表わした.ここで, U_*は底面での摩擦速度, U_*c は底質の移動限界摩擦速度, S, W, Dはそれぞれ河道の縦断勾配,幅,深さである.沖積河道の河道形状示数は,上流から下流へ一般に減少するので,河床形態はタイプ1→2→3→4と配列すること,すなわち,上流から下流方向へ砂礫堆は次第に形成されなくなること,また,ある河川の一断面においては,流量の変化に伴って,その地点の河床形態のタイプが変化しうることを示した.

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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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