A practical method to determine the zero-plane displacement height, d, under unstable conditions was proposed. In this method, two empirical equations for wind profile were used to fit to measured wind velocities. The height at which wind velocity is zero in these equations was expressed as d_w, or d_e. The effects of wind velocity and atmospheric stability on d were evaluated owing to the effects on d_w or d_e.
The values of d determined with this practical method were compared with those calculated from the flux-profile relationship for wind velocity. The friction velocity, u_*, and the heat flux, H, both measured by the eddy correlation method over the grass land under unstable conditions, were used in calculating the latter d. The value of H was used in determining the former d with the proposed method. The universal function with k=0.35 or k=0.40 proposed previously was used in the fluxp-rofile relationship for wind velocity, where k is the von Karman's constant. Fair agreement was found between the above two values of d.
When the flux-profile relationship for wind velocity with k=0.35 or k=0.40 proposed previously was adopted under each condition, and when the values of d determined with the here proposed method were used, fair agreement was found between u_* estimated from each flux-profile relationship for wind velocity and u_* measured with the eddy correlation method. Therefore, it is considered that the universal function for wind velocity with k=0.35 or k=0.40, derived from d=0, can be applied also over the roughness surface.

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Fingering of water pathways was investigated with the help of laboratory experiments, in the case of two layered soil whose upper layer was finer and less conductive than the coarser layer beneath, under the presence of ponding water over the upper layer.
Experiments were performed using vinyl chroride cylinder 19.5 cm in diameter and 30 cm long, assembled by connecting fifteen rings each 2 cm long. This technique facilitated three dimensional observasions of wetting front by means of taking photographs of horizontal cutting planes from the soil interface to bottom of the cylinder in steps of the ring height.
The material for coarser layer where circular water pathways were found, consisted of glass beads whose size was 0.600-0.355mm. The variation of size distribution of fingers and the number of fingers with the flow rate were studied.
It became clear that within the range of small flow rates, the number of fingers increased linearly with the flow rate and were scattered over the whole cross sectional area. When the fingers began to merge together at higher flow rates, fingers started to form into blocks of wetted fraction. These figures were very complicated and were far from being circular in shape.
It appeared to be misleading to conclude that an increase in the finger width in two dimensions would represent an increase in the diameter of fingers in three dimensions.

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After the transfer of agricultural land ownership beyond the border of municipality, the owner commutes to his acquired agricultural land. This paper call commuting cultivator beyond the border of municipality “Commuting Farmer”. Some municipality in suburban area has the high rate of Commuting Farmer. This paper discusses the influence of high rate of Commuting Farmer on regional agricultural landuse. The survey area is 40km from Tokyo CBD.
The analysis is to plot the distribution of Commuting Farmer's living place and Commuting Farmer's agricultural land in survey area, to evaluate the agricultural landuse condition and to compare the Commuting Farmer's regional difference.
1) The Commuting Farmer's living place distributes mainly more urbanized area. The Commuting Farmer's agricultural land distributes mainly Agricultural Land Zone.
2) The Commuting Farmer's agricultural land's crop tends to be different from native farmer's crop. But the rate of underuse agricultural land is almost same.
3) The Commuting Farmer from urbanized area is long distance for cultivation. But, date of commuting is same and intention for farming is relatively positive than that from suburban area.
According to the questionnaire, the underuse of agricultural land is more related to succession. This fact suggest that as Commuting Farmer's agricultural land is successed, the rate of underuse agricultural land will be increase.

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In addition to safety and functional features which must be considered in the design of a concrete gravity dam, it has become necessary to address the aesthetic effects on the surrounding landscape. Due to the subjective nature of an aesthetic evaluation, however, it is difficult to acquire objective data concerning aesthetic factors.
In order to address aesthetic factors in a quantitative way, a survey was conducted in accord with psychometrical technique. Two methods were employed including the “method of paired comparisons” and the “method of rank order”. The results of the survey were then used to train artificial neural networks. It was verified that the resulting networks are capable of generalizing these data. In this way, the quantitative evaluation of aesthetic factors supporting the design of a concrete gravity dam was accomplished.

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The purpose of this study is to establish a method using Landsat-5 TM data for the measurement of the turbidity distribution in the interior part of the Ariake Sea, which has great influences on the environment, ecosystem and marine products. The relationship between the turbidity and spectrum of the sea area, the properties of path radiance in TM data, and the procedures for atmospheric correction and measurement of turbidity distribution were discussed on the basis of turbidity and spectrum which were obtained from in situ measurement, and Landsat-5 TM data.
The results indicated that the spectral radiance just above the sea-surface in the wavelength range from 0.4μm to 0.85μm was closely related to the turbidity, but that beyond the wavelength of 0.95μm it was almost zero, and the path radiance, which occupied about 90% to 70% of the radiance of TM Bands 1 to 4, was dependent on the law of about-3th power of wavelength. A reasonable and simple method of atmospheric correction for TM data by using the radiance of TM Band 5 which seemed to be equivalent to the path radiance over the sea area and the dependence of path radiance on the wavelength was also presented. Moreover, the turbidity distributions in the study site were exactly measured by the regression equation between the turbidity and the ratio of radiances of TM Band 3 and Band 2 which were corrected for the atmospheric effects.

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An arrangement of fine-grained soil overlying coarse grained soil along a sloping contact can, under appropriate circumstances, hal infiltrating water away from the coarser material. Such an arrangement is called a capillary barrier. The water halted by a capillary barrier flows downward above the contact. This type of flow is named a funneled flow. The amount of funneled flow increases in the downward direction as additional infiltration is halted by the barrier. Sufficiently far downward, the funneled flow wets the contact to the point that an amount of water equal to the infiltration penetrates vertically into the coarse soil mostly in the form of a fingering flow. The lateral distance at such a point is defined as the diversion capacity of an inclined capillary barrier.
Diversion capacities of the inclined capillary barriers were measured experimentally by using a rain fall simulator under which one of two types of transparent Hele-Shaw models, a small model or a large model, filled with a Hyojun sand layer over a coarse glass beads layer was placed. Since both of the unsaturated funneled flow model proposed by Ross and the saturated funneled flow model proposed by Kung are two dimensional models, they were modified into three dimensional models by using a catchment factor. Soil physical parameters which depend on the bulk densities of materials were corrected by using non-similar media scaling technique. These modifications significantly improved the ability of predictions of the measured diversion capacities.

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The authors investigated the relationship between the length of paddy field and the inlet flow rate from the viewpoint of irrigation for puddling. The paddy field irrigation during the period of puddling is the same as the border irrigation which is one of several methods of field irrigation. There were two advance equations derived by incorporating two kinds of infiltration equations into the volume balance equation, which was used in the border irrigation. The methods determining the parameters of infiltration equation based on the observation of advance distance were established. Through irrigation for puddling in the paddy fields, the advance distances were observed at equal intervals of time. By using these values observed, the infiltration parameters were estimated, and several values of advance distances were computed as time elapsed by substituting the parameters into the advance equations. The computed result showed a good agreement with the observed data.
By varying the inlet flow rate, the advance distances were computed and the relationship between the length of longer side and the inlet flow rate was investigated for water to reach the downstream end within allowed time. Result shows that the longer the longer side of the paddy field becomes, the larger the inlet flow rate is required for water to reach the downstream end within allowed time. Therefore it can be clearly shown that, if the inlet flow rate for the length of longer side of 100m is regarded as a standard, and the inlet flow rate is increased in correspondence with the ratio which extended the length of longer side is divided by 100 m, the irrigating water will reach the downstream end within allowed time.

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This study is conducted to verify how the water quantity and quality of irrigation water for paddy fields be affected by the runoff EC flux where the watershed is small and the paddy fields are within the watershed. In order to verify this facts, a watershed which encompasses an area of 205 ha was selected and is categorized as small. The irrigation water quantity and quality at intake point of the paddy field are measured. The data regarding rainfall, runoff, and EC values of the outlet of the watershed are also recorded. Further, a phisycal model (WATER QUALITY TANK MODEL) of water quality is developed to verify how irrigation water quantity and its water quality affect runoff quantity and runoff pollutant load. The model is applicable for different land use and is tried to simulate the fluctuation of water quality in the present study. The results indicate the importance of paddy fields within that small watershed in reducing the runoff EC flux. Further, the model simulation results accord well with those observed at the outlet of the watershed. And the authors entered the data, which were taken by Suzuki et al., into the model and tried to estimate the discharge and water quality of irrigation water for a term of 1985. As the results, the estimated water irrigation quantity was just as same as today and EC value was slightly greater than that of today. Other important water quality parameters such as nitrogen and phosphorus are underway and will be presented next.

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The area of desolated field caused by an excess spring water is increasing, especially in the low lying paddy field at valley bottom. In this paper, the authors reported the method for controlling spring water by mean of horizontal interceptive layer. This method enables one to capture the spring water with interceptive layer and guides the intercepted water to underdrains. The dynamic characteristics of spring water in several conditions were analyzed by finite element method, and reliability of calculated results were confirmed with sand model examination.
The results obtained are summarized as follows;
1) The separately installation of underdrains and interceptive layer produces higher drainage effect in comparison with closely installation.
2) When the spacing between underdrains and interceptive layer attains to a specified length, mean groundwater level becomes minimum and water table shows flat.
3) In case the interceptive layer has less permeability than a critical value (K_c), drain capability of that method is a almost equal to impermeable layer method. When interceptive ratio (L_s) is estimated at 25%, K_c is about 1% of coefficient of saturated water conductivity.

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In depopulated and aging rural areas, the importance of the rural improvement is increasing in recent year. Especially, the agricultural road improvement is very important for the sake of activating rural areas. In this improvement, the cut slope causes a serious problem from the standpoint of natural environmental protection.
In this paper, we investigated physical profiles of cut slopes and conducted a questionnaire for landscape evaluation with Semantic-Differential method. The model for landscape evaluation was formed making use of these obtained data. And applying covariance structure model, we analyzed the relationship between the physical measurements on a cut slope and the subjective-psychological judgment on landscape evaluation by the medium of latent factors about the cut slope of agricultural road. As a result of analysis, we can investigate statistically the significance of causality under assuming proper factors, and obtain operational information for landscape improvement using the proposed model for analyzing landscape evaluation. Therefore this model is considered as a useful method for designers with the improvement planning.

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Considering the possibility that hydraulic fracturing is induced in a dam body or foundation by the cracks which occurred during construction, caused by an earthquake or shrinkage due to drying, it is important to obtain the mechanical properties of the material of a dam body and foundation. To measure small strains and avoid bedding errors, gap sensors were used in laboratory test on foundation clay soil of Oyachi reservoir.
It is well known that the ratio of tensile strength to compressive strength of a hard material such as rock is 1/10-4/15. However, the test to obtain tensile strength of soft clay of pyroclastic ash loam has been scarcely carried out. In order to investigate the growth of tensile cracks in a dam body or foundation, it is important to evaluate the relationship between tensile strength and strain. A series of tensile tests on foundation clay of pyroclastic ash loam were performed using thick wall cylindrical specimens. Based on these tests, the characteristics of foundation soil in tensile region were compared with those in compressive region for disturbed and undisturbed soils. When the leakage in Oyachi reservoir occurred, ground water was observed only in the dam foundation (undisturbed soil) and no seepage water was observed in the dam body (disturbed soil), hence it was concluded that the leakage was through the foundation.
Based on the test results mentioned above, it was found that tensile and compressive deformation moduli are nearly equal in the level of small strain and the ratio of tensile strength to compressive strength is about 1/5-1/4. The dam foundation was confirmed to be over?consolidated and the tensile strain at failure for disturbed soil is 3-6 times as large as that for undisturbed soil. This suggests that the cracks can occur much more easily in the dam foundation than in the dam body.

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In this study, a new method is described for a digital image processing technique (photo montage method) in the photoelastic experiment. Especially, the central position of an unclear photoelastic fringe pattern can be decided rapidly and precisely in the experiment. As an applicable example, the stability of the underground space model is estimated by using the system. The experimental model specimen is set up neighboring underground spaces each other.
From the results of this experiment, it was found out that isochromatic lines grew around underground spaces (circular holes in the specimens) under a loading point. At the middle part of the neighboring structures each other, the higher order isochromatic lines were connected, which showed unstable conditions.
The results of this experiment (in the plane stress condition) gave good agreement with the tendency that was obtained by the elastic FEM analysis in the plane strain condition. However, it was difficult to take own weight of a specimen into consideration essentially as for the photoelastic experiment. This procedure must be recognized fully that it is always an elastic analysis.

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We carried out a questionnaire survey on municipalities of the Integrated Rural Development Model Project districts to grasp actual conditions of development and use of village parks as a basic investigation to develop planning method for village parks.
In this report, we discuss park size and location based on this analysis as they are the fundamental basis for park planning and development. We obtained the following results about characteristic tendencies:
(1) Objective value of park size per head and district are especially used in securing park size.
(2) Municipal officers have an awareness of shortage of actual park size, they desire securing park size suited park function.
(3) There are especially many problems such as over enlargement of usage area or difficulty in securing necessary park size in lower population areas. The current basic-unit-based method sacrifice to suitable usage area in securing park size.

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We carried out a questionnaire survey on municipalities of the Integrated Rural Development Model Project districts to grasp actual conditions of village park development as a basic investigation to develop planning method for village parks. In this report, we discuss park location, land selection and facility development, based on this analysis. We obtained the following results about characteristic tendencies:
(1) Municipal officers strongly tend to believe that existing public facilities have priority over settlement area in their relative locations, for land selection of village parks.
(2) It is difficult to secure land for parks, and conditions in selecting park location, such as safety, etc., tend to be the victim in securing park size.
(3) Requests for convenience facilities, etc., are tending to diversify. It shows that municipal officers are seeking to diversify the character of village parks.

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Property of artificial bed soil with continuous fibers which is sprayed on steep slope and growth of arboreous plants planted there were discussed. Growth of arboreous plants planted by seeding were well, and height reached about 2m for 4 years. Root system of arboreous plants grew not only artificial bed soil but also into cracks in rock and weathered rock, as it shows excellence compared to herbaceous plants even if dry period. Additionally, the results indicated. that the revegetation bed soil plays significant role during initial growth stage and moisture condition for plants standing on slope was better at lower part of it, which results in better growth of arboreous plants there.

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